Putting the Treat into Treatment: Teaching Owners to Get from the Living Room to the Exam Room in a Calm State Mikkel Becker, CPDT VetStreet.com Seattle, WA

Walking tools that help owners gain control over their pet’s forward motion and direction without the use of force are front clip harnesses and head halters. It’s important to use fixed length leashes and to avoid retractable leashes, especially with fearful animals, as numerous problems are likely to occur with such tools and there’s a general lack of control. Cat harness and leash can be used to teach kittens and relaxed adult cats to follow and have protected time outdoors. Such walking devices also make the relationship more interactive and provide another form of control useful for minimal restraint during exam if the animal is accustomed prior. Teaching animals to relax in the car is another important way to reduce stress before the animal has even arrived. Decreasing the anxiety of being in a crate, then reducing aspects of the car that might be stressful (such as noises and motion sickness) along with Victory Visits to fun places can help reduce anxiety. For some animals simply training outside of the car or sitting in the car while getting their meal, treats or doing training may be a helpful place to start. Victory Visits are one way to practice elements of the veterinary visit that are made to be more like the actual vet visit while being kept positive and at a rate the animal tolerates. Victory Visits are done in preparation for actual exam and treatment at the hospital and are preventive in building up a positive association with the clinic. classes and kitten socialization guidance are other strategies for building a more social, less aggressive and more handling tolerant animal from the start. To get animals to move on or off of things or to approach something targeting, luring and tossing treats are all helpful strategies. Treating is one helpful strategy for counter conditioning an animal to the veterinary experience. But, in many cases the treat rate is far too low and the reward value or treats given is minimal for the animal. Rather than one to three harder treats given during the visit have an arsenal of available treats, toys and other rewards to employ. And, employ the tastiest, most enjoyable treats possible at a fast rate to keep the animal occupied during exam and procedures. One tactic is using distractions and feeding or keeping the animal’s attention on something else throughout the procedure. Or, another useful strategy for decreasing anxiety longterm is conditioning the animal to tolerate handling. AAHA guidelines are helpful for incorporating behavior guidelines and checks into regular veterinary visits to address problems early and often. The sooner a behavior issue is addressed the better chance it has for being resolved. Many issues get worse, not better, when left on their own without treatment.

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Fear Free Handling- Understanding the Art, Design, and Feel of this Fashion Tech-Style Jonathan Bloom, DVM Willowdale Animal Hospital Toronto, Ontario, Canada

Many pet owners fail to identify, and are reluctant to address, conditions such as dental disease and arthritis in their pet because they don’t see the disease, and they don’t appreciate the negative impact that it has on the body. In contrast, most pet owners are EXPERT at identifying fear and anxiety in their pets, and owners are very much aware of how a negative experience can impact both their pet’s mental health and wellbeing. Experience and careful observation reveal that those sentiments are not restricted to just the outpatient visit, but also apply and contribute to the pet owner’s reluctance to hospitalize their pet. In addition, pet owners are reluctant to approve necessary routine procedures such as collection and x-ray for much the same reason. Implementing strategies to maximize patient comfort is the most prudent way to create successful experiences while visiting the hospital. Pet owners visiting my practice have been overwhelmingly accepting and appreciative of the efforts made to ease their pet’s fear and anxiety. Technicians have been performing common procedures such as blood draws, nail trims, and x-rays the same way for decades. But just because it has become the norm, doesn’t mean that staff like it! No staff member likes being bitten by a , or scratched by a cat. No staff member loves donning protective leather gloves to hold a cat for a nail trim or to remove an IV. No staff member loves stretching pets out in an unnatural and uncomfortable position to take an x-ray. And no staff member loves working in an environment with barking and whining pets. We all work very hard and want to be appreciated for what we do. It is much more rewarding when pets can be gently controlled for nail trims and IV placements, when pets can be calmly positioned for x-rays, and when the background noise from the dog wards can be kept to a minimum.

Identifying fear and anxiety in the hospitalized pet A problem well stated is a problem half solved! Proper care for out-patient procedures and for hospitalized pets start with the proper identification of fear and anxiety. Veterinary healthcare providers need to pay more attention to signs such as trembling, hiding under bedding, vocalizing, body position, and lack of comfort behaviours etc.

The pet’s surroundings and housing Common belief has long been that are colour blind. Dogs can however see many of the same colours that humans can see. Fear Free™ has developed a colour palette that was selected to be both positive and visually comfortable. Bright lighting can also be uncomfortable for pets. Dimmable lights are ideal. Cages are believed to best suited for housing when there is opportunity for looking outward with few obstructions, or have the option to retract to an area when less sensory stimulation is present is also ideal. This can be achieved by providing boxes, tents, or partial covers so pets can choose their level of stimulation.

Sample collection Attention should be paid to commonly performed procedures such as blood collection, urine collection, IV placement and removal, treatment of wounds etc. Procedures used to make these more comfortable experiences often include the use of compression wraps, topical anesthetics such as Emla cream, pharmaceuticals, and environmental control.

Radiology For years, pets have been forced into dark X-ray rooms, stretched out onto hard table tops, placed on their backs with their legs being squeezed by the vice like grip of lead lined gloves, while their limbs are pulled in 4 different directions. There is nothing natural or enjoyable about this for pets. Retakes are numerous, and X-rays are often of compromised quality. Several options including compression wraps, pinch induced behavioural inhibition, or pharmaceuticals are often used to create faster, better quality, more comfortable x-ray experiences for pets.

Post-operative care Pets often experience stress and anxiety due to the direct result of pain. Careful attention must be paid to regularly assessing and addressing pain relief in our hospitalized pets. Environmental control is also critical in ensuring a smooth, comfortable post-op recovery including consideration given to noise levels, music, pheromones, body positioning etc. My staff have never been more eager to accept a fresh and innovative healthcare initiative in the past as they have been for FEAR FREE™. They realized that they are surrounded by calmer, happier, and more easily handled pets. As a result, staff are working in a more safe and in a more enjoyable work space. Subsequently, staff satisfaction and staff morale have never been higher. The creation of a Fear Free™ philosophy and culture benefits pets, pet owners, hospital staff, pet healthcare, and the business as a whole.

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Dental Charting: It is More than Just Xs and Os Vickie Byard, CVT, VTS (Dentistry), CVJ PetED Veterinary Education and Training Resources Warminster, PA

As a frequent consultant and instructor, I have the incredible opportunity to meet many of you within your own practices. When I ask if you chart your dentistries, most of you enthusiastically report that you do. This is a positive change from the past. Now, I would like to take this opportunity to look at the dental chart in detail and review the importance of this document. But before we start looking at the document and how to record your findings, I recommend we review some anatomical terms as they relate to the mouth and associated structures. First, you should know the proper and expected dentition of and kittens versus adult dogs and cats. In the puppy, there are no deciduous first premolars or molars. In the kitten, there are no deciduous molars. Also, it important to know the eruption schedules. In the puppy, primary or deciduous teeth begin to erupt around 3-6 weeks of age. Usually, by 6 months of age, the adult teeth are replacing the primary teeth. Also, it should be mentioned here that many of the “micro-breeds” tend to experience a delayed eruption. This is important information when planning treatment options for extracting retained deciduous teeth. Begin the assessment of the head by looking at your patient squarely in the face and note any swellings or asymmetry while the patient is still awake and conscious. Note any facial abnormalities such as unilateral facial swellings. If the patient is cooperative, a conscious intraoral exam can be very beneficial is case planning as well. Things to note are; the bite, tooth occlusion and any tooth-to-tooth contact and any tooth-to-tissue contact. The tissues of the gingiva, the mucosa and the lips all should be examined and notes made of any abnormalities. Also, note any odor, discharge, swelling, tumors, etc. Once you feel a good conscious intraoral exam was performed, the patient should be anesthetized for the comprehensive assessment. This is when you are able to gather the most information. One person should be performing the examination and another should be recording the information. It is a good practice to have the person who is performing the anesthesia make the notations on the dental chart.

Tooth identification There are several different methods of referring to each tooth. A tooth can be identified with an abbreviation. For instance, the left upper fourth premolar would be noted as LUPM4. The benefit of that is that everyone can understand that. The other method is called the modified Triadan numbering system. The first number refers to the quadrant that the tooth is found. The second and third refer to the tooth position starting rostral and moving caudally. The right upper arcade is the 100 series, 200 is the left upper arcade, 300 series is the left lower arcade and the 400 series is the right lower arcade. Tooth 401 would be the right lower first incisor and tooth 411 is the right lower third molar. Deciduous teeth are the 500,600,700 and 800 series in the same pattern. The modified Triadan numbering system applies to the cat dentition as well. The difference is that they have fewer teeth. The cat have no upper first premolars, they have no first and second premolars on the lower arcades and there is only one molar in each arcade. So here are some easy landmarks for you:  The first incisor is always 01  The canines are always 04  The first molars are always 09 Anatomical direction:  Tooth surfaces that touch the front lips – labial  Tooth surfaces that touch cheeks – buccal  Tooth surfaces that touch palate – palatal  Tooth surfaces that touch tongue – lingual  Anterior portion of a tooth – rostral  Posterior portion of a tooth – caudal So, once you have performed the complete visual oral assessment, it is time to start making notes on the dental chart. The purpose of a dental chart is to make record of the state of the mouth on that day. A veterinarian that was not involved in the procedure at all should be able to understand exactly what condition each tooth was in just by looking at this chart. Often I have gone to practices that state they chart their dentistries. In fact what they do is circle all missing teeth and “x” out all extracted teeth. Complete charting involves much more than that. There should be adequate room to make notes as to signs,

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diagnosis, treatments, prescriptions and take home instructions. An anatomical graphic showing every expected tooth in that species should be present and large enough that you can make notations of periodontal probing depths on at least two surfaces.

Periodontal probing Since the statistic is that 70-85% of all companion pets over the age of 3 have periodontal disease, we need to make notations as to the pocket depth on each tooth. Without these numbers, there is no way that we can follow the progress of the therapy. There are a number of periodontal probes available. I find that it is easiest for measurement of pocket depth is you choose a Williams periodontal probe. This instrument has markings at each mm. There is a heavier band at 4-5mm, 9-10mm, 14-15mm. This instrument is positioned parallel to the crown and gently guided under the sulcus of the tooth until the tip reaches the ceiling or the floor of the pocket. The intention of the technician using this instrument is to detect and measure periodontal pockets and clinical attachment loss. At the very least measurements should be recorded at the deepest pocket depth on the mesial and buccal aspects of the teeth and the lingual and palatal aspects of the teeth. Any pocket depth greater than 1 mm in a cat or 3mm in a dog is considered a periodontal pocket. Other critical notations are tooth fractures; enamel fractures, uncomplicated crown fractures, complicated crown fractures, uncomplicated crown root fractures, complicated crown root fractures and root fractures. The classification of these fractures can be found at www.avdc.org. An explorer is the very pointed tipped instrument used to enhance tactile sensation. This instrument allows the technician to detect any abnormalities in enamel integrity. The sharp end will transfer a change in feel when in contact with tooth resorptions, enamel hypoplasia and carious lesions.

Other gross clinical observations All other abnormalities should be noted:  Discolored teeth  Fractured teeth  Mobility  Furcation exposure classification  Tooth resorption classification (www.AVDC.org)  Fistulae  Crowding  Tooth rotation  Abrasion versus attrition  Enamel defects  Foreign bodies  Oral masses  Supernumary teeth  Stomatitis A very comprehensive list of appropriate abbreviations can be downloaded from http://www.avdc.org/traineeinfo.html. Intraoral radiographs are taken and those findings associated with each tooth should be noted on the record. Once the veterinarian has made a diagnosis and treatment plan, this is shown and noted on this chart as well. As you progress in increasing your dentistry skills, there will be more and more things diagnosed and different treatment options will be offered and provided. This document will be your way of providing a means of clear communication for individuals within your practice and to those you are referring care. The standard of care expected by the state boards in relation to dentistry is increasing every year. AAHA standards also make it clear that good record keeping and charting for dentistry services provided is expected. Since the down turn in the economy has hit dentistry services and surgery services hard across the country, we should look at this opportunity as a “speed bump”. Speed bumps are provided in order for us to slow down and evaluate the current conditions. This is an excellent opportunity for us to take this skill to the next level.

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Dental Equipment Maintenance and Technician Safety Vickie Byard, CVT, VTS (Dentistry), CVJ PetED Veterinary Education and Training Resources Warminster, PA

A current trend in veterinary medicine is a reduction in elective surgeries in small animal practice. Spays and neutering procedures are being done earlier and earlier at the rescue or at low cost clinics. That change has affected the small animal practice dramatically which has focused much attention to the mouths of our patients. Small animal general practitioners are looking towards dentistry as a way of increasing wellness care while supporting the operating and treatment room activities. With an increased focus, there is an increase of the number of dental procedures being performed in practice and this necessitates us to look at both equipment maintenance and technician safety. There is nothing more frustrating than equipment failure during a procedure for both the veterinarian and the technician. Therefore, is it important to schedule some time during the week that will be devoted to equipment maintenance.

Dental unit compressor maintenance Some dental units come equipped with a small compressor. Some practices have a compressor outside of the dental department and the units are connected with quik-connections. In either case: Oil-cooled compressors have either a view or a dipstick with which to monitor the oil level. This should be checked weekly. Consult your compressor’s owner manual to determine the type of oil required. Condensation also accumulates in the barrels of the compressors. There are drains (either wing nut type or screw type) at the bottom of the compressors. These air storage tanks need to be drained weekly for busy dental departments and monthly for smaller departments.

High speed handpiece maintenance After use 1. Remove the handpiece from the dental unit tubing. 2. Wipe the outside of the handpiece with a clean gauze or towel moistened with or alcohol. If you have a handpiece equipped with a fiber optic light source, make sure that is wiped clean as well. Do not use harsh cleaning solutions and do not vibrate in the ultrasonic cleaner. 3. With the bur in place, spray a short burst of special handpiece lubricant (refer to manufacturer’s owner’s manual) into the air drive hole. This is usually the smaller and often shorter of the holes. 4. Reattach the handpiece to the dental unit tubing and depress the foot pedal for 30 seconds allowing the lubricant to circulate through the handpiece and to expel any excess oils from the air line. Allow the lubricant from the handpiece to discharge onto a paper towel and inspect for color. This should all be clear. If not, repeat the lubrication process described above until it is clear. 5. Remove the old bur. 6. Dry the exterior of the handpiece thoroughly (any excess oil will soak through the autoclave pouch, disrupting instrument sterility and will risk paper char). 7. Follow manufacturer’s owner manual for autoclave time and pressure (Never exceed 135 degrees C). Before use 1. Place a new or sterilized bur in handpiece. Secure in appropriate bur into the chuck of the handpiece and finger tighten the chuck closed around it by mounting the Chuck Wrench or by releasing the Push Button on the end cap of the Push Button Type handpiece. 2. Spray lubricant into drive air hole. 3. Allow handpiece to run for 20-30 seconds. Cartridge replacement 1. If, after lubricating the high speed handpiece, there is excessive drag (the handpiece is not spinning with adequate RPM), it may be necessary to replace the turbine cartridge. 2. A bur should be in place. 3. Use the manufacturer’s end cap wrench to remove the end cap turning the wrench counter-clockwise. 4. Gently push the turbine out by pushing gently on the bur. 5. Remove debris from the turbine from the inside of the handpiece with a cotton tipped applicator. 6. Insert a new turbine into the head of the handpiece by aligning the locating pin to the guide dot on the head. 7. Make sure the back of the cartridge sits flush with the back of the handpiece. 8. Secure the end cap back in place with the end cap wrench. 843

Low speed handpiece maintenance 1. If your low speed handpiece has a motor section with a detachable sheath, the motor does not need to be sterilized. 2. Slide the attachment ring up to detach the sheath. 3. Dental motors and sheaths require a higher viscosity oil than high speed spay. 4. One to two drops of oil in the drive airline is all that is necessary. 5. Attach the motor to the drive airline and run to distribute the oil. 6. Wipe away the excess with a paper towel. 7. The straight sheath does not require lubrication. 8. Clean the outside with a moist gauze or paper towel and dry. 9. Place in a sterilization pouch and sterilize. Disposable polishing angle 1. It saves maintenance times because you simply through it out. 2. No cross contamination. 3. 90 degrees reciprocating head a. Does not wind into long hair of some animals. Autoclavable prophy angle 1. Dip the head of the prophy angle in a small amount of handpiece cleaning solvent. 2. Run for 1 minute changing directions of the gears from forward to backward. 3. Wipe off and insert prophy cup. 4. Periodically follow the manufacturer’s instruction in the owner’s manual and disassemble the prophy angle to oil the gears. Hand instrument sharpening 1. Put a drop of sharpening oil on an Arkansas Sharpening Stone 2. Hold the dental instrument either against a firm surface at a 90 degree angle to the floor with the toe facing you. 3. Place the oiled sharpening stone at a 115 degree angle and move up and down until a sharp angle is obtained. 4. Wipe filings and excess debris off with a conical stone. Winged elevator sharpening 1. Match the angle of the back edge of the winged elevator against the Oiled Arkansas Stone. 2. Hold the instrument steady. 3. Move the stone down the back of the instrument on the right side, then the middle then the left. 4. Use the conical stone on the inside of the winged elevator to remove filings. 5. If there are notches in the instrument left from improper extraction techniques or if the instrument has been bent, send it off for professional instrument care OR replace the instrument.

Operator/technician safety Ergonomics 1. Maintain proper posture a. Upper back i. Your elbows should be at a 90 degree angle ii. Use magnification and good lighting to reduce the need to bend the neck and shoulders b. Lower back i. Adjust the height of the seat so that your feet are flat on the floor with your knees slightly lower than the hips. c. Hands i. Hold the instruments in a modified pen grasp 1. Neutral position 2. Relaxed position 3. Stabilized hands when possible Personal safety 1. Contaminants a. Two foot spray, splash and spatter zone b. Wear eye protection at all times i. Goggles ii. Safety glasses iii. Chin length full face shields

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c. Wear mask i. Have a filtration level of at least 95% ii. Minimize goggle fogging d. Protective clothing i. Really should protect your skin and work clothes (CDC) e. Gloves i. Right size ii. Allow for good tactile sense 2. Radiation a. 6 foot 8 inches from beam when barriers are no available b. Primary Barriers (needed when within the beam) i. Lead gowns ii. Lead curtain c. Secondary barrier i. Dry wall is considered an appropriate secondary barrier d. Dosimeter i. Collar level

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Dentistry for Our Feline Friends and Their Special Needs Vickie Byard, CVT, VTS (Dentistry), CVJ PetED Veterinary Education and Training Resources Warminster, PA

One of the biggest revelations for me in my training as a veterinary technician was that cats are not small dogs. That statement is especially true in relation to the subject of veterinary dentistry. As with most other subjects in medicine, we must start with anatomy and the differences unique to our feline population as a species.

Unique anatomy Tongue The tongue is covered with papillae. These barbs point backwards and this enables the cat to rasp meat off of bones and to groom more effectively. Theses barbs catch debris and dirt while grooming. Unfortunately, because the barbs on a cat’s tongue points backwards, anything that gets attached to these barbs eventually gets swallowed. That includes things like hair and string. Hairballs are a common issue for cat as are string foreign bodies. Once tangled in the papillae, the material cannot be spit out. Teeth Cats have a unique dental formula. Theirs is I3, C1, P3, M1 I3, C1, P2, M1 Their canine counterparts are supposed to have 4 premolars and more than one molar. So, it is important to know that when charting the feline patient, their teeth on the maxilla start at the second premolar (there is no first) and on the mandible, the first tooth distal to the canine is the third premolar (there are no first and second mandibular premolars). Gingival probing depths In our feline patients, normal gingival probing depths are less than 1 mm. Canine teeth The canines have a vertical grooves that extends the length of the tooth. These sometimes become stained. It is important to note that the enamel is thinnest in this area and care must be taken not to spend too much time trying to remove the staining for fear of damaging the protective enamel. Also, the pulp canal extends ALL THE WAY to the tip of the crown of the feline canine tooth. Any degree of chipping of these teeth require investigation. A “wait and see” approach is not appropriate. These injuries must be radiographed. Nearly all fractured canine teeth are painful and will become infected.

Common feline pathology Juvenile onset gingivitis This occurs before cats are 9 months old. There is a severe gingivitis and notable halitosis. Often these cats little to no tartar accumulation. The exact cause is unknown but treatment involves early detection and frequent (q 4-6 months) professional plaque removal with elegant home care. Usually, true juvenile onset periodontitis will resolve by the age of 2 years. It is often noted that juvenile onset gingivitis occurs frequently in specialty cats such as Abyssinians and Persians. Canine tooth extrusion (supereruption) Sometimes when a canine tooth is effected by chronic periodontal disease, there appears to be a greater crown height. Although the etiology is unknown, current studies reveal a statistical correlation between supereruption and tooth resorptive process. It is important to note; when the veterinarian is making the recommendation for the extraction of a maxillary canine tooth when the lower canine tooth on the same side remains, it is critical that the client be prepared that there is a chance for maxillary lip impingement. Alveolar bone expansion (osteitis) Caused by chronic periodontal inflammation the alveolar bone around the upper canine teeth. When noted it is critical to evaluate the periodontal structures of these teeth radiographically to stage the periodontal disease in order to know the appropriate therapy. By Stage 4 periodontal disease and 50% bone loss, tooth extraction should be considered. Tooth resorption Tooth resorption is a common ailment in our feline population. Studies have reported anywhere from 20% to 75% of the feline populations will experience this disease process. These lesions are usually noted buccally but can occur on any surface. Statistically the most commonly affected teeth are the mandibular third premolar. On the cheek teeth, the lesions are commonly noted at the cementoenamel junction and with hyperplastic gingival tissue covering the affected portion of the tooth. In the canine teeth, it is common to see tooth resorption more apically and may not be clinically apparent. At one time these lesions were called neck lesions, FORLs (Feline Odontoclastic Resorptive Lesions) and cervical line erosions. The current terminology is tooth resorptions. They are classified: 846

 Stage 1: Mild hard tissue loss  Stage 2: Moderate hard tissue loss but that does not extend endodontically  Stage 3: Moderate hard tissue loss but that does extend endodontically but most of the tooth integrity is maintained.  Stage 4: Extensive Hard tissue loss that extends endodontically  Stage 5: Crown has fractured off due to hard tissue weakness and the gingiva has extended over top of the remaining root tissue. The etiology of this disease process is unknown and being researched extensively. Recent studies have grouped these lesions into two groups:  Type 1: Resorption associated with periodontal disease where the tooth retains radiographic evidence of a periodontal ligament and a pulp canal. These teeth need to be treated with complete extraction.  Type 2: Lesions associated with bone replacement. These teeth can be treated with crown amputation with intentional root retention. Determination of treatment options can only be made radiographically. Stomatitis This is one of the most painful conditions for cats and definitely one of the most frustrating syndromes to deal with for the owner AND the practitioner. The etiology is unknown specifically but appears to be associated to an immune mediated reaction to either dental plaque or the tooth structure itself. Usually there are many factors involved; genetics, environmental stress, diet and viral infections. Although, for a while it was suggested that feline Bartonella virus was responsible for stomatitis cases. However, although many cats may be infected with Bartonella, it is more probably an opportunistic pathogen ad not the primary cause. These cats present painful. They often drool, have a history of weight loss and poor appetite and their coats are unkempt due to their inability to groom themselves comfortably. Some cats only have inflammation around the caudal cheek teeth, while others exhibit a generalized inflammation. This disease is very frustrating. Medical therapies such as corticosteroids, antimicrobials, Gold Salts, Interferon all have mixed long-term results. When feline patients present with inflammation associated only with the teeth caudal to the canines, surgical extraction of the teeth and all root fragments caudal to the canines is the treatment of choice. It is recommended that if one is to treat a stomatitis case, they must have intraoral radiology capability. It is critical that all root tissue be removed as well. The accidental retention of root tissue will lead to continued gingival inflammation. Since in the best case scenario, extraction can provide a 50% chance of resolution, post- op radiographs are vital to insure that the case has been properly treated. Patients also should be supported via feeding tube if is an issue until they are able to eat on their own. Post-operatively most veterinarians will put these patients be on appropriate antibiotics for 2 weeks post-op with appropriate pain management. In summary, feline patients have some unique issues that the trained veterinary technician should be aware of in order to support the veterinarian and the owners.

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Out of Sight! Are Intraoral Radiographs Important for a Complete Dental Assessment? Vickie Byard, CVT, VTS (Dentistry), CVJ PetED Veterinary Education and Training Resources Warminster, PA

Are dental radiographs essential for professional veterinary dental care? Absolutely! In practices that use radiology to evaluate dentistry patients with obvious clinical findings, radiographs revealed additional pathology in 50% of dogs and 53.9% in cats. In cases that had no gross pathology present, radiology exposed clinically relevant findings in 27.8% of dogs and 41.7% in cats. So, when practices are providing dentistry without evaluating the health of the tooth below the gum tissue, they are missing a vast amount of disease. To provide this service, a dental X-ray unit is not necessary. For some years, vet dentists used their regular medical X-ray unit successfully. The key is to use intraoral film. This task is awkward and time consuming. Often it means transporting the anesthetized patient to a totally different room in the practice. But, it can be done. Many veterinary hospitals site cost to the clinic as the number one reason for not purchasing a dental radiographic unit. Unfortunately, they are mistaken. Of all pieces of equipment in a practice, this unit is relatively inexpensive. To purchase a regular dental X-ray unit, the cost would amount to about $4,000. If the practice goes digital, software and sensor can cost from $6,000 to ~ $9,200. A cost analysis is valuable when evaluating the profitability of equipment. Let’s say, for example, a practice is performing 3 dentistries per day. On the average they take (and this is very conservative) 10 radiographs per day. The average fee is $10-20 per view, so let’s split it in the middle…$15 per radiograph. That produces $150 per day. Do these 5 days per week; the practice generates $750 per week. Do these 50 weeks per year, the practices produces $37,000 per year. The equipment paid for itself in less than 6 months just on the revenue brought in by the images itself. I haven’t included the increased pathology found and the revenue generated by treating it. These numbers are very reasonable in a large, multi-vet practice. Consider a small, 2 vet practice. Let’s imagine they perform 3 dentistries per week. They take 10 radiographs per week at $15 each. That is $150 per week. Do these 50 weeks a year and the practice has grossed $7,500 a year. The equipment in that scenario paid for itself in less than 2 years. After the equipment is paid off, except for incidental supplies, the rest is all profit. To use a medical X-ray unit, it is preferred that the head of the unit can be lowered and the angle changed. A focal distance of 12 inches is best. To be able to use the bisecting angle technique is often necessary to reposition the patient. Different X-ray units have different technique charts but you can try using 100 mA, 65 kVp at 1/10th second and adjust the technique accordingly. Dental radiographic units have heads that are more adjustable so that the patient does not have to be manipulated and repositioned as much. The radiographic detail is much better. So, once a practice decides it is interested in providing this service, some training and education is required. Fortunately, there are many venues for this education. There are numerous training facilities across the country; there are convenient online courses, many wonderful books and journals. Recognizing normal versus abnormal requires some knowledge of each. Safety is also an important factor. It certainly is a fact that digital radiographs require about 1/10th of the radiation required when exposing film. But, that doesn’t mean that one shouldn’t prudently provide radiation protection. Stay 6 feet away from the head of the X-ray unit, do not stand directly in the line of the beam, do not hold the sensor with your hand, and always wear your radiation badge. There are hand-held X-ray units available. These are often sought because they do not take up a large footprint within the dental operatory. But, their approval is provided for use at an arm’s length. These units are heavy and that may be difficult. Once you have obtained the equipment and you have training in getting diagnostic images, it is important to begin to understand the baseline for normal versus abnormal tooth development and pathology. I recommend the following book when you are first getting your feet wet in this service: Atlas of Dental Radiography in Dogs and Cats, 1e by Gregg A. DuPont DVM FAVD DAVDC and Linda J. DeBowes DVM MS DACVIM DAVDC (Jul 25, 2008) In a normal, young patient, it is important to know that the dentinal wall is very thin and the pulp chamber is wide. As the patient ages the dentinal wall thickens hence the pulp canal narrows. Also, in very young animals, the apex of the tooth is still open. As they age, the apex closes. Indications for radiographs are vast:  areas where there are missing teeth o Impacted teeth often cause dentigerous cysts. As the tooth is developing, there is a sac of epithelium that covers the crown of the tooth. During eruption through the gingiva, the sac is lost. If the tooth is embedded, 848

the sac remains and often begins to secrete fluid. As the fluid accumulated, a cyst forms. As the cyst enlarges, the surrounding bone is destroyed.  to evaluate teeth experiencing periodontal disease o It is not enough to clean a periodontal pocket without radiographing the tooth to evaluate bone loss and whether or not the patient has secondary endodontic disease.  to document destruction caused by tumors, including epulides o when evaluating tumor or epulide activity, radiographic findings should accompany the biopsy so that the pathologist can consider this in his/her diagnosis  to evaluate discolored, worn or fractured teeth o Is there endodontic disease and what are the options for care?  prior to extraction o What are the roots like? . Sometimes there three roots on a two rooted tooth . Sometimes the root is already fractured or resorbed . Sometimes mandibular molar roots curl at a 90 degree angle . Sometimes mandibular molar roots cross  Are the roots ankylosed? o No point in trying to take out a root if it has been incorporated into bone (usually feline)  What is the quality of the remaining bone o Is there sufficient bone to safely extract a tooth without fracturing the jaw? o Is there already a jaw fracture?  post extraction o this documents complete root extraction o it documents the remaining integrity of the bone  facial trauma In summary, to provide complete and professional dentistry that will keep your patients happy and healthy, radiographic evaluation is very necessary. Extracting a tooth without radiographs is the same as repairing a femoral fracture without radiographs. Some specialists feel that by the end of the decade, dental radiographs will be standard of care in veterinary medicine. Our clients are becoming ever so much more sophisticated in their expectations for their veterinary care. This is everyone’s opportunity to be ahead of the curve rather than trying to play catch up.

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Periodontal Disease: The Most Prevalent Disease in Veterinary Medicine Vickie Byard, CVT, VTS (Dentistry), CVJ PetED Veterinary Education and Training Resources Warminster, PA

Peri- : Prefix meaning around or about -odont: having to do with tooth -ium: indicates a biologic structure If we use this information, it means that periodontal disease is a disorder of structure having to do with the tissues that surround and support the teeth, including the gums, cementum, periodontal ligament and alveolar and supporting bone.

The structures of a tooth  Enamel: hard white substance covering the crown of a tooth  Dentin: the main boney part of the tooth beneath the enamel and surrounding the pulp chamber and root canals  Gingiva: the gums of the mouth. The gingiva is made up of epithelial tissue that is attached to the bones of the jaw and surrounds and supports the bases of the teeth.  Gingival sulcus: the groove between the surface of the tooth and the epithelium lining the free gingiva.  Free Marginal Gingiva: the portion of the gingiva that surrounds the tooth and is not directly attached to the tooth surface.  Attached Gingiva: the portion that is firm, resilient, and bound to the underlying cementum and alveolar bone.  Cementum: A bonelike substance covering the root of a tooth.  Alveolar bone: The alveolar process is the thickened ridge of bone that contains the tooth sockets on bones that bear teeth.  Periodontal Ligament: the fibrous connective tissue that surrounds the root of a tooth, separating it from and attaching it to the alveolar bone, and serving to hold the tooth in its socket.  Furcation: the space between two roots Periodontal disease is the most prevalent medical condition affecting our dogs and cats. As a matter of fact, it is suggested that most pets over the age of three years of age are experiencing some level of periodontal disease. Bacteria in the mouth form a thin, slimy film on the teeth, otherwise known as biofilm. When that biofilm covers the teeth, it is called plaque. If the plaque is not removed, the minerals in the saliva join with the plaque and harden into a substance called tartar or calculus. The bacteria secret toxins and that sets off an inflammatory response. This is the primary cause of periodontal disease.

There are stages of periodontal disease  Normal: Clinically normal. No inflammation evident  Stage 1 PD (periodontal disease): Gingivitis without any attachment loss  Stage 2 PD: Early periodontal disease. There is less than a 25% attachment loss and/or a stage 1 furcation involvement.  Stage 3 PD: Moderate periodontitis: There is a 25-50% attachment loss and/or a stage 2 furcation involvement.  Stage 4 PD: Advanced periodontitis. There is a greater than 50% attachment loss and/or a stage 3 furcation involvement. Periodontal disease is much more than just an aesthetic issue for pets and their owners, although the odor may be the client complaint necessitating the visit. Periodontal disease can lead to oral discomfort, as well as tooth loss. It has also been strongly documented in human medicine a link between periodontal disease and numerous problems such as an increased risk of stroke, myocardial infarction, atherosclerosis and difficulty regulating diabetes due to the inflammation. It has also been suggested that people over 60 years of age may suffer from delayed memory as well. We now have studies in dogs showing a correlation between periodontal disease and microscopic changes in heart, liver and kidney tissue. The periodontal patient needs first to have a thorough assessment, cleaning, and charting to determine the degree and severity of the disease process. Radiographs are also needed to determine if there are any teeth endodontically challenged secondary to the periodontal disease. A critical piece of the puzzle is determining the ability and willingness of the owner to provide care at home. Although there are treatments available, if the owner is not willing to provide meticulous home care, severely affected teeth should be extracted. In the event you have an owner that is motivated to do home care, treatment options are:

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Root planning and subgingival curettage When periodontal pockets have been identified, it is imperative that the plaque and calculus be removed from the root surface. Ultrasonic and sonic hand pieces can be used hasten the work, since our veterinary patients are under general anesthesia. The scalers actually vibrate at a frequency that breaks down bacterial membranes. This does hold a therapeutic advantage. However, the tips do not provide the same horizontal flat surface as hand instruments do. Therefore, it is recommended to follow ultrasonic pocket treatment with engaging the curette with the root surface and pull with a downward motion in a cross hatch fashion. The goal of root planing is to scale the root. Since the cementum is softer, it is more affected by tartar build up and inflammatory by-products. So root planing removes the roughened cementum, impregnated with toxins. Care needs to be taken not to be overly aggressive in planing. Cementum itself does contain substances that augment attachment. The pocket itself needs to be treated as well. A curette is used to debride the diseased tissue from the pocket, leaving a healthier tissue bed for healing and reattachment.

Perioceutics These are products that are employed to provide a medicant to the disease periodontal pocket. Doxirobe gel (zoetis) This is a doxycycline polymer preparation that comes as a two syringe system. The polymer syringe mates with the antibiotic syringe. The plungers are depressed in a back and forth motion 100 times. A blunt cannula is attached and can be bent to whatever angle is most appropriate. The gel is introduced into the treated periodontal pocket (greater than 3mm deep). A few drops of water on the gel and the matrix harden. A plastic filling instrument or titanium covered beaver tail instrument is used to pack the material into the pocket. This will remain in place for 2-3 weeks. Another advantage of Doxycycline is that it has an anticollagenase effect. This aids in tissue reattachment. Clindoral (TriLogic pharma) This is a preloaded syringe system that comes ready to use. Attach the blunt cannula and with the head of the pet upright, instill the Clindoral filling the pocket. Hold the head in the same position for 1-3 minutes for complete gelation. An instrument can be used to pack the material. The material slowly resorbs over a 7-10 day period. Consil and osteoallograph Guided Tissue Regeneration. Both products are synthetic bone graft materials. This is a more advanced procedure and referral to a dental specialist may be indicated if your veterinarian is not familiar with this product. This is a material that is most effective for areas where there has been vertical bone loss. This procedure is a surgical procedure necessitating a surgical flap. Care must be taken to rule out any oral nasal fistulae or antral nasal fistulae. Otherwise, these materials will migrate into the sinuses and will be very irritating for the patient.

Systemic antibiotic use When providing periodontal therapy, these sites are considered “open and draining”. Treatment by combining scaling and extraction is not an indication for systemic antibiotic treatment. There are, however, some specific indications for adding a systemic antibiotic:  When local tissue is severely infected and periodontal therapy required surgery to expose bone or if teeth were extracted from severely infected bone.  Osteomyelitis  CUPS (chronic ulcerative paradental syndrome): mucosal immunopathy  Prevention of bacteremia in specific cases o Patients with clinically evident cardiac disease o Patients with clinically evident renal or hepatic disease o Patients with prostheses; ocular, total hip replacements, patients with anterior cruciate repairs using nonabsorbable material o Patients with splenectomies o Patients with clean surgical procedures with severe periodontal disease o patients o Patients with concurrent auto-immune disease

Home care When periodontal therapy is provided, it is critical to provide explicit home care instructions:  List all dispensed and when should the client begin the medications  When may the patient eat next and what may they eat?  When may the client resume or begin tooth brushing?  When is their recheck appointment? 851

 When do you want to schedule the next dentistry? This is influenced by the client, the size and breed of patient, the budget of the client, etc. Periodontal disease is the most common condition in our companion pet population. Prevention is the gold standard and that includes owners brushing their pet’s teeth…daily. Probably one of the most important activities the technician plays is in educating the client on how to maintain a healthy mouth.

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Special - Stress Management and Substance Abuse in Veterinary Medicine Vickie Byard, CVT, VTS (Dentistry), CVJ PetED Veterinary Education and Training Resources Warminster, PA

As in many aspects, veterinary medicine lags woefully behind our human medicine counterparts. We, as a profession, are slow to adopt change; nowhere more importantly than in our ability or desire to address the profound personal needs of our colleagues. At an April 2012 meeting at the Betty Ford Center, the statement was made that statistics from the Centers for Disease Control and Prevention show that drug overdose has now surpassed automobile accidents as the leading cause of accidental or injury in the country. It is estimated that 30,000 Americans will die from prescription drug overdose this year. The reason that this became an important issue for me was that as of 2008, I began a 12-step program of my own. I live in a moderate sized town. Once I got entrenched in this program, I was alarmed at the number of professional and paraprofessional colleagues employed in veterinary medicine I met that were also dealing with an addiction of one sort or another. I began to . Now, I am not much of a mathematician and I am certainly not a statistician but I began some simple math. If I know 6 colleagues from one town in Pennsylvania, and there are 2,563 municipalities in PA then there may be over 15,000 colleagues in one state alone. Multiply that times 50 states…well, the numbers don’t add up considering there were only 90,000 some veterinarians employed in the US and about 71,000 veterinary technologists and technicians. But it made me aware of a serious problem within my profession. And, these are the numbers of colleagues that have found some sort of help. Statistics show that the number of people still struggling with additive substances always outweighs those that find recovery. So, is there a problem in veterinary medicine? Well, I think we need to look at the suicide rate of veterinarians. In March of 2010, Bartram published a paper in the Veterinary Record showing that our British colleagues are faced with a higher risk of suicide as compared to the general population and double the risk of other health care professions. What are some of the factors suggested in that paper?  Personality characteristics of those entering the veterinary field  Work related stressors  Ready access to drugs  Comfort with the concept of euthanasia  Stigma associated with mental illness  Professional and social isolation It only makes sense that if suicide is an issue within our profession, we need to be looking at one of the precursors to that and that is substance abuse. The Centers for Disease Control and Kaiser Permanente produced the ACE study. ACE stands for Adverse Child Experience. 17,000 Kaiser patients voluntarily participated in the study and it produced staggering data suggesting that trauma during childhood development dramatically increases the health, social and economic risks. See www.ACEstudy.org. We joke about the fact that it is the wrong reason to go into veterinary medicine because you don’t like people. As an instructor, I have repeated to countless students that there is a person at the end of every leash or holding every cat carrier. But I have to wonder how many of us gravitated towards this profession for that very reason. Having assisted with the administration of hundreds of MBTI (Myers-Briggs Type Indicator) personality tests in veterinary medicine, I have noted a strong tendency towards introversion in both the veterinarian and the technician populations. So, first let’s consider personality types. What type do you identify with? In the 1950’s these personality types were identified as risk factors for heart disease: Type A: Impatient, hurries, under pressure, prompt and often early for appointments, watches clock, walk/talk/eat rapidly, does multiple activities simultaneously, lives in the future/always planning, feel that 'there's never enough time'. Type B: relaxes readily focuses on the quality of their life paces themselves easygoing 'one day at a time' less ambitious lower incomes/grades less irritable. The Type A personality group experiences a significantly greater chance of having heart disease because they experience stress more strongly. Many of us in the United States have not been taught to deal with stress appropriately.

What is stress?  A “Physical, mental or emotional strain or tension.”  A “condition or feeling experienced when a person perceives that demands exceed the personal and social resources the individual is able to mobilize.”

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 A “Physical, chemical or emotional factor that causes bodily or mental tension and may be a factor in disease causation.”  A “ state resulting from stress; especially one of bodily or mental tension resulting from factors that tend to alter an existent equilibrium.” There are individuals that can experience a stressful experience and move into an adaptive stage. The flip side are those that move into an exhaustive stage. If one is not able to move to an adaptive stage, the exhaustive stage of stress the individual is sensitized or primed for future stressors! To be able to handle the frequent stressors appropriately, we have to find ways to adapt in healthy ways.  Experiencing the feelings without guilt or shame  Sharing the unpleasant feelings with a friend or confidant  Exercise/yoga  Community  Mindfulness/meditation Unfortunately, some that find stress unbearable, resort to unhealthy ways to de-stress…drugs and/or alcohol. If, healthy stress relievers are not cultivated, addiction can be right around the corner. So, what is addiction or chemical dependency?  Loss of control - abuse of substance  Need-dependency (physical and psychological)  Continued use despite consequences  Tolerance (need more of substance to get the same effect)  Withdrawal (physical, psychological) Why can some people drink and never have a problem and other struggle so?  Biology - genetic predisposition (10% of cases)  Psychological - "addictive personality"  Social - family dynamics predispose o one parent with substance abuse: the child is 4-5 times more likely to abuse o both parents abuse: the child is very likely to abuse o Adult survivor of child abuse o PTSD: self- And how do you know you have a problem?  Have you ever decided to stop drinking for a week or so, but only lasted for a couple of days?  Do you wish people would mind their own business about your drinking-- stop telling you what to do?  Have you ever switched from one of drink to another in the hope that this would keep you from getting drunk?  Have you had to have an eye-opener upon awakening during the past year?  Do you envy people who can drink without getting into trouble?  Have you had problems connected with drinking during the past year?  Has your drinking caused trouble at home?  Do you ever try to get "" drinks at a party because you do not get enough?  Do you tell yourself you can stop drinking any time you want to, even though you keep getting drunk when you don't mean to?  Have you missed days of work or school because of drinking?  Do you have "blackouts"?  Have you ever felt that your life would be better if you did not drink? Many of our veterinary colleagues are dying of this. If you think you have a problem, there is plenty of help available. It is not hopeless.  Twelve-step programs (free and virtually everywhere and online)  Rehab o FMLA . Entitlement . Under the Family and Medical Leave Act of 1993 (FMLA), most Federal employees are entitled to a total of up to 12 workweeks of unpaid leave during any 12-month period for the following purposes: . the birth of a son or daughter of the employee and the care of such son or daughter; . the placement of a son or daughter with the employee for adoption or foster care; 854

. the care of spouse, son, daughter, or parent of the employee who has a serious health condition; or . a serious health condition of the employee that makes the employee unable to perform the essential functions of his or her positions. . Under certain conditions, an employee may use the 12 weeks of FMLA leave intermittently. An employee may elect to substitute annual leave and/or sick leave, consistent with current laws and OPM's regulations for using annual and sick leave, for any unpaid leave under the FMLA. (The amount of sick leave that may be used to care for a family member is limited.  Intensive Out-patient Programs I have seen people that have struggled with addiction lose their license and inability to get to work due to loss of their driver’s license. Getting your veterinary license back is very hard and expensive. It is so much easier to address the wounds, learn new coping skills and get honest. We also have to create a pathway to health for our coworkers. Create a strong policy and make it safe to say; ”I think I may have a problem”. If substance abuse is stigmatized in our work places, our dependent co-workers will struggle in silence. It is important to remember; substance abuse is a disease. The addicted colleague deserves the same compassion you would afford one that had cancer or some less stigmatized disease.

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How to Talk with Clients about Alternative and Raw Diets Ed Carlson, CVT, VTS (Nutrition) IVG Hospitals, Inc. Woburn, MA

All-natural, organic, corn-free, grain-free, gluten-free, raw, BARF, kibble, canned, semi-moist, freeze-dried, frozen; there are so many types of pet foods available today. How do you know which to recommend to your clients or to feed your own pets? This can be quite a controversial topic! Advocates of many diet types often adamantly believe their choice of diet is the absolute best, and some will passionately defend their beliefs, whether based on facts, anecdotal information, or misinformation. Let’s take a look at some diet option types, pros/cons, facts and misconceptions.

Home cooked diets Some owners enjoy cooking for their pets; others feel they are providing superior nutrition, some believe their pet will not eat or will not enjoy commercial foods, others prepare limited ingredient recipes. Preparing home cooked diets for pets is often more time consuming and expensive than feeding commercially available options. There are countless books, websites, articles, and blogs with recipes for home cooking dog and cat foods unfortunately very few are actually complete and balanced. Clients that wish to prepare their pets food at home should be strongly encouraged to consult with a veterinary nutritionist to ensure the diet is nutritionally complete. Clients should also be counseled to follow the recipe exactly as formulated and not to substitute or eliminate ingredients. Limited ingredient home cooked recipes designed for elimination trials can be very useful to determine if a patient is sensitive to a particular ingredient. These diets are intended to only be used on a short term basis under the supervision of a veterinarian as they are often not nutritional balanced. Once the ingredient the pet is sensitive to is identified the veterinarian will often recommend a complete and balanced commercially available diet or consult with a veterinary nutritionist to develop a complete and balanced home cooked recipe. Owners preparing these elimination diets must not make any changes to ingredients unless directed to do so by a veterinarian. These patients should also not receive any treats or foods other than those in the elimination diet. It is extremely important to stress to clients they must follow the recipe exactly as formulated and not to substitute or eliminate ingredients.

Organic and all natural diets The term “organic" refers to the handling and processing of ingredients and products; it does not describe the quality of a product. In order to use this term on the label pet foods and treats must comply with the USDA's National Organic Program (NOP) regulations. These regulations include ingredient sourcing, ingredient handling, manufacturing, labeling & certification of products using the term "organic" on the product label. When natural is listed on a food label the food should not contain any chemically synthesized ingredients. If “natural with added and minerals” appears on the label the vitamins and minerals may be chemically synthesized. “Holistic”, “organic”, “human grade”, “premium”, and “gourmet” are purely marketing terms and have no legal definition.

Corn free diets Corn has also been labeled by some owners/breeders as a cheap filler that causes allergies and is not well digested by dogs and cats. Actually corn provides a highly available source of complex carbohydrates and is an excellent source of linoleic acid (an essential fatty acid which is important for healthy skin), essential amino acids and fiber. Despite what some owners believe documented allergies to corn are quite rare. The ingredients that are most commonly associated to adverse reactions in dogs are beef, dairy products, and wheat; to lesser extent lamb, chicken egg, chicken, and soy. In cats beef, dairy products, and fish are the most common ingredients reported to cause adverse food reactions. Actual food allergies are estimated to be responsible for only 1% of skin disease. Food sensitivities often improve from a diet change but this is not due to a food allergy but rather factors such as increase digestibility of the new diet, , or fiber content.

Grain free diets There have been no studies indicating grain free diets are superior or healthier for dogs and cats. While some grain free pet foods provide excellent nutrition others may not. Potatoes and tapioca, which have a lower nutritive value than grains, are often used in place of grain in these diets. In fact potatoes and tapioca have less protein and more sugar than corn or oats. Some owners mistakenly believe grains are common causes of food allergies however as discussed above this is incorrect. Another common misconception is that dogs and cats foods containing grains are at increased risk of developing diabetes; there is no evidence to support this belief.

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Gluten free diets Corn gluten, which is found in some pet foods, is often blamed for GI issues by some owners and breeders as associated with what they perceive as celiac disease. Celiac disease is rare in dogs and has been reported primarily in Irish . In reality, pets with celiac disease react to the protein in wheat, rye, and barley not corn gluten. Gluten is the concentrated protein from grain after all the starch is removed. Corn gluten is actually an excellent source of protein containing greater than 60% protein and is highly digestible.

Raw, barf, freeze dried and frozen diets Commercial raw diets are available in many forms with frozen and freeze dried being the most common. These are often marketed as complete; others are intended to be fed with additional supplements. The internet is also full of recipes for Bones and Raw Food or Biologically Appropriate Raw Food (BARF) homemade diets. Many of these advocate a formula of 60% raw meaty bones with the remainder of the diet consisting of green vegetables, eggs, milk, brewer’s yeast, muscle meat and organ meats, yogurt, sometimes with some grain and legumes. Meals are not expected to be balanced but rather in theory to be balanced overall by varying the ingredients from one meal to the other. Articles explaining “how to feed raw” quite often advocate feeding muscle meats, organ meats, bones, and fish, with or without vegetables, fruits, grains, herbs, vitamins, and supplements. While some dedicated pet owners will follow these instructions in order to provide this “over time balanced approach” many others, however well intended, will not. Many owners will begin to make substitutions or not continue to dedicate the time and effort this method of feeding may require. Studies on bacterial contamination of raw foods found that 20% to 35% of raw poultry and 80% of raw food diets for dogs tested positive for Salmonella spp, and 30% of stool samples from dogs fed these diets were positive for Salmonella spp. Raw pet food diets have also tested positive for Esherichia coli and Yersinis enterocolitica. Healthy pets may not show clinical signs of illness when ingesting these bacteria however immunocompromised, the very young and the very old are at significate risk. The pathogens found in raw meat also pose a significate health risk to young children, the elderly and immunocompromised people. It is therefore extremely important, anyone preparing these diets, to practice proper hand washing and that all utensils, bowls, and surfaces used for the preparation of raw pet food diets are properly cleaned and disinfected. Raw meat may also contain parasites such as Echinococcus spp, Neospora caninum, Sarcocystis spp, Toxocara canis, Toxoplasma gondii, and Taenia spp. It is also important to note, the feces of pets consuming raw diets can contaminate the environment which may also pose health risks to people and other pets.

Client communication and education What if the diet a client is feeding isn’t complete and balanced? Or if you do not agree with the type of diet a client has chosen to feed? How can you explain your concerns and educate a client that their perceptions are incorrect?  Listen to the client’s reasons for feeding the diet in question and their concerns with other diet options.  Ask open-ended questions to ensure you understand their viewpoint. Be careful not to sound or appear judgmental.  Avoid making disapproving comments, using a negative tone of voice, facial expressions, and body language. If you are perceived as judgmental, condescending, closed minded, or unwilling to listen and consider their point of view or beliefs clients are likely to become defensive or simply unwilling to listen to your advise.  Gently point out any misconceptions or false information offering references to the correct information.  Some owners turn to alternative diets out of concern that their pet won’t eat more conventional diet options. These owners may express concerns of their pet not eating as the cause for not wanting to change diets.  Some owners will not be interested in hearing your advice. Others may listen; perhaps discuss or debate the issue with you but not be willing to make any change to their feeding practices. Be respectful and don’t take it personally; making a nutritional recommendation does not ensure the owner will follow your recommendation.  As with any medical advice; document the patient’s nutritional history and your nutritional recommendation in the patient record.

Nutritional recommendation Remember to make a nutritional recommendation for every patient every time they present to your hospital. Consider the patients age, weight, body condition and muscle condition scores, life stage, life style, and any health issues. Recommend the diet you believe is the best for that particular patient but remember you may also need to consider the owners perception of what is the best diet for their pet. When you have done your best to educate your client but they insist on feeding a diet you do not think is best, consider if there is a way to improve the patient’s diet. Perhaps the client would agree to have a veterinary nutritionist evaluate the diet and if not nutritionally balanced suggest improvements. If they are feeding a grain-free diet that does not contain highly digestible ingredients perhaps you can help them find one that does. If corn free is all the client will consider, research the available options and recommend the one you believe is best suited for your patient. Suggest or provide a referral to a veterinary nutritionist for the client that wants to prepare a home cooked diet or a raw diet.

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Remember the goal of a nutritional recommendation is to provide the patient with the best possible diet. If the client is not willing to follow your recommendation, what recommendations can you make to improve the patient’s diet? Be a nutritional advocate for your patients!

References Hand, et. Al, Small Animal , 5th edition L. Freeman, et. al, Grain-free diets: An alternative option, but don’t dismiss the grains, 2012 Case LP, et al.,eds. Canine and Feline Nutrition 3rd edition, 2011 Freeman LM, et. al, Current knowledge about the risks and benefits of raw meat-based diets for dogs and cats. JAVMA 243:1549-1558, 2013

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Nasogastric Feeding Tubes: The Technicians Role Ed Carlson, CVT, VTS (Nutrition) IVG Hospitals, Inc. Woburn, MA

Feeding tubes are generally tolerated well by most patients and most feeding tubes are relatively easy to place. There are two types of feeding tubes that may be placed by technicians – Nasogastric (NG) and Nasoesophageal (NE)) tubes. Nasogastric (NG) tubes are inserted into the nostril, through the nasal cavity into the esophagus, terminating in the . Nasoesophageal (NE) tubes are inserted into the nostril through the nasal cavity terminating in the distal esophagus. Nasogastric (NG) and nasoesophageal (NE) tubes are useful for patients who are unwilling to or are unable to eat but have normal GI function. Placement does not require anesthesia and usually can be done without sedation by using a topical anesthetic. They are used short-term, usually less than 14 days, and are sometimes used until the patient is stable enough to be anesthetized for a longer term feeding tube placement if necessary. NE/NG tubes are contraindicated in patients that are actively vomiting, comatose, do not have a gag reflex, or have nasal tumor / nasal disease. Since these tubes are generally quite small (usually 8 French or smaller) patients may be fed only liquid food. Complications associated with NE/NG tubes include epistaxis caused by nasal mucosa irritation; aspiration pneumonia should the tube become dislodged due to vomiting or regurgitation; and esophageal stricture (a condition which is rare).

Nasogastric (NG) and nasoesophageal (NE) tube placement Materials needed for placement include: 1. Tetracaine or proparacaine 2. Sterile lubricant jelly 3. Appropriate sized tube 4. 2.0 or 3-0 nylon suture material 5. Scissors 6. 22-gauge needle 7. Permanent marker 8. Empty 6cc syringe 9. 6cc syringe of sterile water 10. E-collar To insert the NG or NE tube: 1. Elevate the patients muzzle and apply a few drops of a topical anesthetic, such as Proparacaine Hydrochloride Ophthalmic Solution USO, 0.5% into the nostril you have selected for tube placement. Allow 5 minutes before attempting to insert tube. 2. While you are waiting, place a stay suture as close to the nose as possible. 3. An easy way to place a stay suture is to quickly insert a 22-gauge needle through the skin at the point where the wing of the nostril meets the fur. With the needle in place insert a 2.0 or 3.0 nylon suture through the needle from the beveled tip and out the hub of the needle. While holding the suture remove the needle. Tie a square knot closely to the skin but loosely enough to allow passing another suture under it. 4. Measure and mark the tube. 5. The NE tube measures to the 7th or 8th intercostal space. The tip of the tube will fall in the distal esophagus. 6. The NG tube measures to the last rib. The tip of the tube will fall either slightly before or in the stomach. 7. Apply sterile lube to the tube. 8. Holding the patients muzzle with your non-dominant hand begin inserting the tube with your other hand. Press the patient’s nose upward using the thumb of the hand that is holding the muzzle. 9. Once you have inserted the tube about the length of the patient’s muzzle, lower the patients head pointing its nose downward slightly. These motions should help guide the tube into the esophagus rather than the trachea. 10. Continue to advance the tube until you have reached the mark you made when measuring the tube prior to placement. The patient may or may not swallow during placement. Gently stroking the throat may encourage swallowing which may assist the feeding tube to more easily pass down the esophagus. 11. If the patient begins to cough at any time during placement, STOP, remove tube and try again. Lack of coughing DOES NOT ensure the tube is not in the trachea! 12. Attach a 6 ml syringe to the tube and check for negative pressure.

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13. If negative pressure exists, flush 5 – 6 ml of sterile water into tube. If the patient coughs the tube is in the trachea. If the patient does not cough placement MAY be correct; confirmation with a radiograph is recommended. 14. Cap the tube with an cap and temporally suture the tube to the stay suture leaving long tails to secure the tube in place once proper placement is confirmed. 15. Confirm placement with a single left or right lateral post procedural radiograph. 16. Once proper placement is confirmed, secure tube with Chinese finger trap. The Chinese finger-trap suture is perfect for feeding tubes; it continues to tighten if the tube is tugged. Pass a long piece of suture through the previously placed stay suture and secure with a square knot. Then begin the Chinese Finger trap pattern. The suture is wrapped around the tube, crisscrossed and tied into a square knot. Repeat a minimum of 5 crosses. For red rubber tubes each throw should be pulled tight enough to make a small indentation in the tube. For silicone tubes pull tightly however indenting these tubes may cause them to become occluded. 17. Secure the other end of the tube in a second location either on the cheek (the facial nerves run across this area of the cheek so the suture should go through the skin but be kept as superficial as possible) or on the top of the head. Tie a loose square knot near the skin then secure the tube with a second square knot. 18. This may also be done with the 22-gauge needle method described above. Smaller diameter tubes may also be attached in this second location with surgical staples. 19. The patient may require an E-collar to prevent tube removal.

Beginning assisted feedings Before beginning assisted feeding it is important to determine the patient's Resting Energy Requirement (RER). RER represents the energy requirement for a normal animal, which is not fasted, at rest under thermoneutral conditions. Two common methods for calculating the patient's RER are: RER = 70 x (body weight in kg) ¾ RER = 30 x (body weight in kg) + 70 The first equation calculates a more accurate caloric requirement. The second formula tends to overestimate the actual caloric needs of very small patients and very large patients. The general recommendation is to begin feeding ¼ of the patients total RER for the first 12 hours and, if well tolerated, to increase by ¼ the total RER every 12 hours until full RER is reached. If at any time the patient vomits, discontinue feedings until vomiting has resolved, reduce volume by ¼ when feeding is resumed, and increase volume more slowly.

Nasogastric (NG) and nasoesophageal (NE) tube feedings Only liquid veterinary diets should be used for feeding through NG and NE tubes. CliniCare® Canine/Feline Liquid Diet, which contains 1 Kcal/ml, is a good option. Emeraid® Intensive Care HDN™ Feline and Emeraid® Intensive Care™ HDN Canine are powdered formulas which are mixed with water and are also a good option. The volume of water added can be varied dependent on the diameter of the feeding tube, however the caloric density is reduced as the volume of water is increased. Trickle feeding via constant rate infusion (CRI) is most often used for hospitalized patients, although these tubes may also be used for bolus feedings and to administer oral liquid medications. Tablets should not be crushed and administered via these small tubes. A number of liquid diets designed for people are also available. These diets are typically less expensive then veterinary liquid diets however are nutritionally inadequate and some may contain ingredients that are inappropriate for dogs and cats. These human diets are especially inappropriate for cats as they are too low in protein, taurine, and arginine.

Troubleshooting feeding tubes Flushing the tube well with water after each bolus feeding, or every 4 hours for CRI 's, will usually prevent the tube from becoming clogged with food. Some patients may be irritated by the feeding tube and require a buster collar to prevent them from removing the tube. Some patients with NE or NG tubes may experience excessive sneezing. If this happens, apply a topical anesthetic; gently lift the patients muzzle upward and apply 2 or 3 drops into the nostril the tube is placed in. If the tube becomes dislodged, which usually causes coughing and/or discomfort and distress:  If via CRI, STOP IMMEDIATELY!  If flushing causes coughing – DO NOT FEED! the doctor. The tube may need to be removed or replaced.

Discontinuing assisted feedings When the patient is voluntarily eating 60% of its RER, assisted feedings should gradually be reduced and discontinued when voluntary consumption has reached the patients full RER. Long-term feeding tubes (E & PEG) should not be removed until the patient has been eating its full RER consistently and maintaining its body weight for a minimum of one week or more. 860

References Textbook of Veterinary Internal Medicine, 7th Edition, Stephen J Ettinger and Edward C. Feldman Clinical Textbook for Veterinary Technicians, 6th Edition, Dennis M. McCurnin and Joanna M. Bassert Small Animal Clinical Nutrition 5th Edition, Hand M, Thatcher, Remillard R, Roudebush P, Novotny B

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Nutrition for the Noncritical Hospitalized Patient Ed Carlson, CVT, VTS (Nutrition) IVG Hospitals, Inc. Woburn, MA

An important area of patient care that is not always given much thought is the nutritional needs of our hospitalized patients. How do we decide what, when, or how much a patient should eat? How should we be documenting what our patients are eating? We all know there are some procedures that we normally recommend fasting but when might this be contraindicated? Should patients that are vomiting or having be fed? What are some methods for getting our patients to eat? How long should we allow a patient to go without eating before we consider assisted feeding? The answer to some of these questions ultimately is the doctors’ decision but remember as veterinary assistants and veterinary technicians we are advocates for our patients! If there are no feeding instructions on a patient treatment sheet discuss the nutritional plan with the doctor responsible for the case. Are there any foods this patient should not be fed? Is there a particular diet the doctor would prefer the patient ate? If the patient refuses to eat that diet may we try other options? If a patient in the hospital is to receive a medication, the treatment sheet clearly indicates what medication, how much, , and when it is to be administered. Why should diet and feeding instructions not be indicated in the same way? Understanding our patients’ nutritional requirements, documenting nutritional information in the nursing notes and discussing this during technician rounds is a vital part of providing excellent patient care! Did Fluffy like to be petted while eating her meal? Did she like her food warmed slightly or prefer it cool? Some patients won't eat if they can't smell the food; heating can bring out the aroma. Some nauseous animals dislike a smelly food, cooling can mask some of the aroma. Did Spot prefer canned food or dry? Often we only offer canned food to patients, epically those that are not eating. But many animals prefer day, especially if that's what they normally eat. Did Lucky like chicken or beef? Is Max food aggressive and lunges if you try to remove his food dish when he is in his cage? Passing along this information from one shift to the next is so important! Even a patient that is well nourished at admission can rapidly become nutritionally depleted during hospitalization. Patients that are already malnourished at admission and that require prolonged hospitalization are at risk for increased morbidity and mortality due to poor nutritional status. Therefore, we must be proactive to ensure that nutritional support of hospitalized patients is not overlooked. Nutritional status should be thoroughly assessed before aggressive nutritional support is initiated. Is your patient well nourished, undernourished, or at risk for becoming undernourished? A nutritional assessment can help identify patients that could develop a deficiency without nutritional intervention. A nutritional assessment should include a complete history (including a diet history), a complete physical examination, a body condition score, and laboratory testing (i.e., a complete blood count, a chemistry profile, and urinalysis).

Calculating calorie requirements How do you know if a patient is eating enough? There are many other formulas to calculate patient energy needs, some for growth, weight loss, weight gain, extremely active individuals, and resting energy requirement (RER). A good starting point for most of our hospitalized patients is to calculate their resting energy requirement (RER). There are several formulas to calculating this, I recommend using one of the following and that you use the one you are most comfortable with. RER = 70 x (body weight in kg) ¾ OR RER = 30 x (body weight in kg) + 70 For example: Sandy weighs 44 pounds, 20.0 kg. 30 x 20kg = 600 + 70 = 670 Sandy’s RER is 670 kcal per day Next determine the caloric concentration of the food you have chosen to feed your patient. (Or that your patient has chosen to eat!) The amount of calories in any food can be easily found on the company website or product guide. The table below contains the calorie content of some of the foods we commonly use in the hospital. size kcal Hill's® Prescription Diet®a/d® Canine/Feline Critical Care 5.5 oz 179 ® Veterinary Formula Maximum- Calorie™/Canine and Feline 6oz 333

Hill's® Prescription Diet® i/d® Canine 13 oz 369 Iams® Veterinary Formula™ Intestinal Plus Low-Residue™ Adult Canine 14oz 417 Iams® Chicken for Dogs 13.2 oz 427.5 Iams® Beef for Dogs 13.2 oz 424

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Iams® Lamb & Rice for Dogs 13.2 oz 427.5

Hill's® Prescription Diet®c/d® canned 5.5 oz 163 Hill's® Prescription Diet® i/d® Feline 5.5 oz 161 Iams® Veterinary Formula™ Intestinal Plus Low-Residue™ Adult Feline 6 oz 169 Iams® chicken for Cats 3 oz 97 Iams® Turkey for Cats 3 oz 95 Iams® Beef for Cats 3 oz 97

Iams® Veterinary Formula™ Intestinal Plus Low-Residue™ Adult Canine dry per cup 259 Iams® ProActive Mini Chunks™ dry per cup 379

Hill's® Prescription Diet®c/d® dry per cup 383 Iams® Veterinary Formula™ Intestinal Plus Low-Residue™ Adult Feline dry per cup 348 Iams® ProActive™ dry cat per cup 372

Once you know the number of calories in a can or cup of the selected food simply divide that number into the patients RER. For example: One 13 oz. can of Hill's® Prescription Diet® i/d® Canine Gastrointestinal Health contains 369 kcal. We determined Sandy’s RER is 670 kcal. Therefor Sandy needs to eat 1.8 cans per day to meet her resting energy requirements. (670 divided by 369 = 1.8) This amount is usually divided into multiple feedings per day. Healthy pets, hospitalized for a spay or neuter, for example, can be offered half this amount twice per day. Other patients, such as a post op abdominal mass removal may require smaller feedings every 4 to 6 hours. For anorexic patients or those that have not been offered food for a period of time should this amount can be introduced slowly, starting with perhaps 10 or 15% of the RER divided into four or 5 feedings per day. If the feedings are well-tolerated, then the amount can gradually be increased by 20 to 25% the following day and so on until the full caloric requirement is meet. It is important to introduce food slowly in anorectic patients to prevent . This syndrome was first described in people with the liberation of Holocaust survivors during World War II. It was found that, after prolonged periods of anorexia, aggressive overfeeding leads to severe metabolic imbalances, which in some cases could be fatal. For example, as and shift back into the intracellular space, severely decreased serum phosphorus concentration can lead to hemolytic anemia. Typically, this is a concern once phosphorus concentration drops below 2 mg/dl and, at this point. Potassium concentration should be monitored closely and supplemented as well. Ideally, phosphorus and potassium concentrations should be monitored daily in these patients for the first few days of feeding. It is also important to remember that liquid diets are often 75% water, so reducing the patients IV fluid rate may be indicated as feedings increase. In general, it is recommended if a patient has not eaten for 3 days or if they are not able to tolerate eating their total caloric requirements for 4 or more days, more aggressive nutritional support must be considered to ensure adequate nutritional intake. These patients may require some type of feeding tube or parental feeding which we will discuss in another lecture.

Nutritional history While you're taking a patient's history, ask the client the questions below regarding the pet's current diet. You may notice some of the questions appear to be similar. The slight variation in the way the questions are asked is meant to prompt owners to think about all the food offered to their pets. For instance, one type of large dental chew is 600 calories and another medium-size one is listed as 188 calories. 1. Has there been any recent history of involuntary weight gain or loss? If yes, how many pounds and during what time period? (Remember, acute, involuntary weight loss is more significant than weight lost over a long period.) 2. Any history of nausea, vomiting, or diarrhea? If so, how often? 3. Any changes in the pet's appetite, urination, or defecation? If so, describe the changes and duration. 4. Does the pet have any difficulty chewing or swallowing? 5. Does the pet have any allergies? 6. Any recent change in the pet's diet? 7. How many people, including children, reside in the household? Who is primarily responsible for feeding the pet? 8. Are there other pets in the household? If so, do they have access to one another's food? 9. What kind of food does the pet eat? (Get specific information, such as brand and product name.) 863

10. How much food does the pet eat? (Get specific data, such as number of cups or number and size of cans.) 11. What commercial pet treats is the pet fed? What brand and size, and how often?* 12. Does the pet get any chew or dental treats? If so, what brand and size, and how often? 13. What table (or people) food does the pet get? How often, and how much?* 14. Do you ever use food to administer medications? If so, what variety, how often, and how much? 15. Do you give the pet any nutritional supplements? If so, what variety, how often, and how much? 16. Does the pet get into the garbage, obtain food from outside sources (e.g. neighbors), or hunt prey? *Always assume the pet is fed treats and people food. Ask “what” they are fed rather than “do you feed”. If you ask “do you feed” some owners may claim not to treat their pets assuming you will not approve.

Getting your patient to eat If a patient has not eaten for 3 days or longer, nutritional support should be considered if it is not contraindicated because of vomiting, regurgitation, or megaesophagus or because nothing can be given by mouth while the patient awaits sedation for diagnostic procedures or surgery. Before initiating aggressive nutritional support, try warming the food and using coax-feeding techniques (e.g., hand feeding; petting and/or talking to the patient in a soothing manner during feeding time). Some hospitalized patients may eat only when alone and undisturbed. Because cats are more likely than dogs to develop fixed food preferences, cats are more likely to eat a familiar food. Patients that usually eat dry food often ignore canned food, and patients that usually eat canned food often ignore dry food. Therefore, it is always important to obtain a complete diet history from the client so that the patient’s food preferences are known before feeding is initiated. I’m not a fan of syringe feeding. I find most animals hate it and find it difficult to force patients to ingest enough food using this method. However some doctors will request a patient be syringe feed and some patients may tolerate it. However if the patient protests I would discontinue the syringe feeding and suggest a different nutritional plan. If, at any time, the patient shows signs of nausea (e.g., turning away from the food, lip smacking, hyper-salivating, regurgitating, vomiting, trying to bury the food) or food aversion, coax feeding should be stopped and administration of antiemetic drugs should be considered. When used appropriately, appetite stimulants can be useful; when used improperly, they can be very harmful. The misuse of appetite stimulants can create a learned food aversion if the patient is forced to eat before being ready. The patient should be thoroughly evaluated before the decision is made to use an appetite stimulant. An appetite stimulant may be considered if the patient is otherwise healthy and blood work results confirm that the patient has fully recovered. Diazepam, a benzodiazepine tranquilizer, is sometime used as a short-term appetite stimulant, especially in cats. Adverse effects of the drug include sedation and, sometimes, agitation and hyperactivity; rare cases of liver failure have been reported in cats after repeated use. Cyproheptadine can have antihistamine and antiserotonin effects in cats. The drug is administered orally and may not be effective for up to 24 hours. Adverse effects reported by owners include hyperactivity, agitation, and aggression. Mirtazapine, a tetracyclic antidepressant, appears to be well tolerated in dogs and cats. Reported adverse effects include sedation, vocalization, hypotension, and tachycardia. Patients with renal disease or hepatic disease should be closely monitored. Antidepressants may affect the blood concentration, so patients with diabetes mellitus should also be closely monitored. Traditionally, dogs and cats with acute vomiting and diarrhea due to dietary indiscretion have been managed by withholding food for 24 to 48 hours for “bowel rest.” Fasting, even for this period of time, decreases the length of the intestinal villi, increases the risk of bacterial translocation, and reduces activity of intestinal disaccharide enzymes. In addition, the bowel does not necessarily “rest” when empty: during fasting, dogs experience migrating motility complexes or “housekeeping waves”; cats experience a similar motility pattern. During inflammation, normal motility is likely decreased and and delayed gastric emptying are present. “Feeding through diarrhea” (i.e., feeding while a patient still shows clinical signs) may help maintain the activity of small intestinal digestive enzymes and help preserve normal villi morphology. The presence of food in the intestine also decreases the risk of bacterial translocation. Further, feeding small amounts may improve intestinal motility and gastric emptying. In some cases of osmotic diarrhea, feeding worsens clinical signs; therefore, patients should be treated individually and feeding stopped if diarrhea appears to worsen. When intractable vomiting is present, oral intake of food should generally be avoided, but for as short a time as possible. In dogs infected with parvovirus, early enteral feeding results in faster resolution of vomiting and diarrhea than does withholding food. Similar to feeding during diarrhea, feeding small amounts may improve gastric emptying and a return to normal motility. Highly digestible foods with a low to moderate fat content should be considered because high-fat diets may slow gastric emptying and promote vomiting in some patients. Parenteral fluids and electrolytes should be provided as needed, and antiemetics should be used if the presence of a GI foreign body has been ruled out. If there is a history of dietary indiscretion and the patient is still eating and not clinically dehydrated, the diarrhea usually resolves with time. Switching to a highly digestible, low-residue food for 5 to 7 days may help the inflamed GI tract absorb while healing occurs. The animal can resume its regular diet after the diarrhea has resolved.

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In many cases, however, conservative management is necessary, with restriction of food intake for 8 to 24 hours, followed by introduction of a bland, highly digestible diet fed frequently in small amounts. Failure to implement a conservative strategy is a common reason for poor response and relapse. Sometimes a secondary bacterial or fungal infection can develop, which may require medical therapy in addition to dietary manipulation. If a foreign body is involved, the introduction of a highly digestible diet is essential for tissue healing and for restoring a positive nitrogen balance after its removal. In some cases, dietary manipulation may be both diagnostic and therapeutic. For example, if the animal has food sensitivity or a true food allergy, switching to a number of different diets may be necessary. Dermatologic signs may be present, but GI signs can appear alone or with skin changes. Intestinal changes are reversible, and normal GI function can return in approximately 6 to 8 weeks. Dietary changes may involve switching to a novel protein or modified protein diet, such as hydrolyzed protein. Some cats are carbohydrate intolerant and develop secondary diarrhea from high-carbohydrate diets. Switching them to a low-carbohydrate, high-protein diet often resolves the diarrhea. Intestinal cancers are generally nonresponsive to dietary manipulation, but a high-quality diet can aid in the ability of the patient to heal, respond to chemotherapy, and maintain adequate nutrition. High levels of fish oils may help in the treatment of some forms of lymphoma.

What can veterinary assistants and veterinary technicians do to provide excellent nutritional nursing care for our hospitalized patients? When a patient is admitted discuss the nutritional plan with the admitting doctor. Are there any foods they should not have? What should they be fed? How much? How often? If the doctor has not taken a complete nutritional history from the client perhaps you can. Refer to the nutritional history taking suggestions above. Don’t leave food continuously with a patient that is not eating. If you are nauseous do you like to have any smelly foods in your face all the time? And canned food left out for hours gets all dried out, discolored, and just plain gross! Document in your nursing notes:  What food does Fluffy like? Remember to include dry or canned, brand, flavor. Or maybe she only likes what the owner brought in? Do we have any left? If so, where is it?  What food does Fluffy not like?  Does Lucky like to eat out of a bowl? Plastic or metal? Prefers a flat plate?  Does Spot eat better if hand fed? Or prefers to eat when no one is looking?  Does Max prefer to eat outside of the cage? Or prefers to eat outside the hospital?  Rex only seems to eat in an exam room when the owner comes to visit? Maybe he will eat for us in an exam room?  How much food has Sandy eaten today?  Zoe isn’t eating. o What have you tried tempting her with? Baby food? Canned tuna? Chicken? Cheese? For dogs maybe try canned cat food? o Have you tried putting a small amount in her mouth? How did she react? o Have you tried syringe feeding? How did she react? Is your patient eating enough to meet their resting energy requirements (RER)?  If the patient is only going to be in the hospital for the day or overnight as with a spay, neuter, dental, small mass removal, etc. not eating their entire RER should not be a problem. Provided, of course, they go home as scheduled and begin to eat once they are home. I recommend making a follow up phone call the day after discharge to ensure your patients appetite has returned to normal.  If your patient is not eating or not eating enough to meet his RER please point this out to the doctor. Work together on a revised nutritional plan! o Ask the doctor if you can try tempting with foods not listed as acceptable on the treatment sheet. What other foods could you try tempting with? Baby food? Cheese? Tuna, Chicken? Canned cat food (for canine patients)? o If, despite your best efforts to encourage your patient to eat, any patient has not eaten for 3 days suggest a feeding tube! And remember that’s including days at home prior to being o admitted not just days without eating in the hospital! Be a nutritional advocate for your patients!

References Firstline Magazine, How to conduct an effective interview with clients. Sep 1, 2010 by: Charlotte Higgins, AS, CVT Compendium June 2013, Vol 35, No 6) Focus on Nutrition: Dietary Management of Gastrointestinal Disease by Marge Chandler, DVM, MS, MANZCVSc, DACVN, DACVIM, DECVIM-CA, MRCVS

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Veterinary Technician, June 2009 (Vol 30, No 6) Nutrition Know-How — Dealing with Diarrhea Woes by Ann Wortinger, BIS, LVT, VTS (ECC, SAIM, Nutrition) The inappetent hospitalized cat: Clinical approach to maximizing nutritional support. Chan D. J FELINE MED SURG 11:925-933, 2009. Nutrition for the Inappetent Cat, Elizabeth Thomosky, DVM, Diplomate ACVECC

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Nutritional Calculations Made Fun and Easy Ed Carlson, CVT, VTS (Nutrition) IVG Hospitals, Inc. Woburn, MA

Calculating energy (caloric) requirements How do you know how much a patient should eat? Is Fluffy eating enough or too much? There are many formulas to calculate a patient’s energy needs -- some for growth, weight loss, weight gain, extremely active individuals, and resting energy requirement (RER). The first step to determining how much to feed is to calculate the patients resting energy requirement. RER is a function of metabolic body size and represents the energy requirement of the patient while at rest at a controlled temperature. There are several formulas to calculating RER. One simple formula is RER = 30 x (body weight in kg) + 70. Example: Sandy weighs 44 pounds, 20.0 kg. 30 x 20kg = 600 + 70 = 670 Sandy’s RER is 670 kcal per day. This formula is generally adequate for medium size healthy patients, however may not be accurate for small or large patients. The formula RER = 70 x (body weight in kg) ¾ provides a more correct estimate of the patients caloric requirements. Example: Tiny weighs 3 pounds, 1.36 kg. 70 x (1.36kg) ¾ = 88.1 kcal/day Tiny’s RER is 88 kcal per day or 30 x (body weight in kg) + 70 = RER 30 x 1.36kg = 40.8 + 70 = 111 kcal/day This calculation estimates Tiny’s requirement as 111 kcal per day; an over estimation of 41 kcal per day! Once you have determined the patient RER, the next step is to calculate the patients Daily Energy Requirement (DER). DER is calculated by multiplying RER by a coefficient based on the patient life stage and body condition. A list of coefficients, for common life stages, to determine DER is listed below.

Canine Feline Growth DER Growth DER Up to 4 months = 3 x RER Growing kittens = 2.5 x RER Over 4 months = 2 x RER

Maintenance DER Maintenance DER Average neutered adult = 1.6 x RER Normal neutered adult = 1.2 x RER Intact adult = 1.8 x RER Intact adult = 1.4 x RER Obese prone = 1.4 x RER Obese prone = 1.0 x RER Weight loss = 1.0 x RER Weight loss = 0.8 x RER

Work DER Light work = 2 x RER Heavy work = 4-8 x RER Example: If Tiny, in the example above, is a kitten and his RER is 88 kcal/day his estimated DER is 220 kcal/day (88 x 2.5). It is important to remember all caloric calculations are estimates of the patient’s energy needs; actual caloric intake may vary from one individual to another. These calculations, however, are an excellent starting point for every nutritional recommendation. Next, determine the caloric concentration of the food your patient is fed. The amount of calories in any food (and some treats) can be easily found on the company website or in their product guide. The caloric content of most “people” food that the patient is fed can be found on the products packaging or company websites. Once you know the number of calories in a can or cup of the selected food, simply divide that number into the patient’s DER. Example: in the above example we determined Tiny’s DER to be 220 kcal/day Dry kitten food “X” contains 523 kcal/cup 220/523= 0.4 867

Tiny should be fed 0.4 cups per day Example: Canned kitten food “X” contains 88 kcal/2.9 oz. can 220/88=2.5 Tiny should be fed 2.5 cans per day Example: Tiny’s owner wishes to feed both dry and canned versions of food “X”. A 2.9 oz. can contains 88 kcal. Subtract this amount from 220 (Tiny’s total DER) - 220-88=132 Then divide the remaining daily kcals by the number of kcals in 1 cup - 132/523=.25 Tiny could be feed 1 can and ¼ cup per day. This amount may be divided by the number of feedings the patient will receive. Remember to be specific in your instructions to your client; include the name of the food you are recommending including the brand, the amount to be fed per day and per feeding, how many feedings per day, how many treats, and when the plan may change. Example: Feed Tiny 1 can (2.9 oz.) and ¼ cup of Food “X” per day. I would recommend putting ¼ cup of the dry variety out for him in the morning and allowing him to graze on it throughout the day and feeding him ½ can of Food “X” in the morning and ½ can in the late afternoon. Tiny is a growing kitten and these amounts will need to be adjusted as he grows until the time he is neutered. We will weigh Tiny and preform a body condition score at his next scheduled visit in 3 weeks. A revised nutritional recommendation will be made at that time. You have indicated you will not be offering Tiny treats at this time. If you begin to offer treats (which most owners do) the amount of food Tiny is fed will need to be reduced by the number of calories the treats contain. For many healthy pets being fed a good quality diet manufactured by a reputable company this maybe all the calculations that are required. But, being a nutrition tech, there are so many other calculations you may want to do!

Dry matter basis vs. “as fed” Ingredients are listed on the label on an “as fed” basis; basically this means that the moisture content is included. In order to compare the nutrients in one food to another, especially when comparing a canned food to a dry food, you must convert each nutrient from “as fed” to “dry matter basis” (DMB). One method to calculate this is to subtract the percentage of moisture listed in the guaranteed analysis section on the label from 100% and then divide the percentage of the nutrient by this number.  Step 1 – subtract the moisture content of the food from 100%.  Step 2 – divide the nutrient content by the DMB. Example: a canned food label lists the moisture content as 75% and protein as 10% (as fed basis).  Step 1 - 100% - 75% (moisture) = 25% DMB  Step 2 - 10% protein divided by 25% DMB = 40% protein  This food is 40% protein on a Dry Matter Basis (DMB). Example: a dry food label lists the moisture content as 10% and protein as 18% (as fed basis).  Step 1 -100% - 10% (moisture) = 90% DMB  Step 2 - 18% protein divided by 90% DMB = 20% DMB  This food is 20% protein on a Dry Matter Basis (DMB). Another simpler, yet perhaps not quite as accurate, method is to multiple the percentages of nutrients listed in the guaranteed analysis by 1.1 for dry foods and by 4 for canned foods. Example: a canned food label that lists the protein content as 10% x 4 = 40% protein (DMB). Example: a dry food label that lists the protein content as 18% x 1.1 = 19.8% protein (DMB). Both of these calculations provide the estimated amount of the nutrients on a dry matter basis. If the actual amount is required it may be obtained from the pet food manufacturer.

Calculating estimated carbohydrate content The amount of carbohydrates a pet food contains is not included in the guaranteed analysis, however it is easily estimated. Start by converting the protein, fat, fiber, and ash contents to the dry matter basis (as explained above). Add these percentages together and subtract the total from 100%. This is the estimated carbohydrate content of the food. Example: Food x contains  Protein – 32% DM  Fat – 20% DM  Fiber – 6% DM  Ash – 12% DM  Total – 70%

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 100% - 70% = 30%. This food contains approximately 30% carbohydrates.

Calculating calorie content Calorie content is not required to be listed on the label of pet foods unless a claim of “light” or “less calorie” is listed on the label. Calorie content can be obtained from most manufacturers websites, product guides, or by calling the company support number. The calorie content can be calculated using the ‘as fed’ amounts listed in the guaranteed analysis of crude protein, crude fat, and the calculated carbohydrate content (as explained above) using the modified Atwater method. The modified Atwater value for protein and carbohydrates is 3.5 kcal/gram and for fat is 8.5 kcal/gram. The sum of these 3 results is added together and the result multiplied by 1.1 for dry foods or 1.2 for canned foods. This is the kcals/gram of the food. To convert to kcals/cup multiply the weight of the food in one 8-ounce measuring cup. Example: Food x is a dry food weighing 90g/cup;, on an ‘as fed’ basis it contains  Protein – 20.2%  Fat – 16%  Carbohydrates – 49.2%  0.20 x 3.5 kcal/g = 0.70 kcal/g o 0.16 x 8.5 kcal/g = 1.36 kcal/g o 0.49 x 3.5 kcal/g =1.72 kcal/g . Total = 3.78 kcal/g o 3.78 kcal/g x 1.1 = 4.16 grams/cup o 4.16 g/cup x 90 g/cup = 374.4 kcal/cup

References Small Animal Clinical Nutrition, 5th Edition, Hand, Tharcher, Remillard, Roudebush, Novomy

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Nutritional Management of Pancreatitis Ed Carlson, CVT, VTS (Nutrition) IVG Hospitals, Inc. Woburn, MA

Acute pancreatitis (AP) is a common illness in dogs and cats. Although many cases are mild and easily treated, some cases develop severe complications that can be fatal. Mortality rates of dogs with severe AP have been reported to range from 27 to 42%. Survival rates in cats with pancreatitis are difficult determine given the high incidence of concurrent disease, such as hepatic lipodosis.

Causes The underlying cause of pancreatitis is not known. In dogs, dietary indiscretion such as table scraps, garbage, and high fat foods are common causes of pancreatitis. Potassium bromide and phenobarbital are also known to cause pancreatitis in some dogs. Other risk factors in dogs include obesity and middle age or older (often over 5 years of age). The dog breeds of Miniature , Yorkshire , Silky Terrier, and the Miniature Poodle appear to be predisposed to pancreatitis. In cats, obesity and dietary factors are not thought to cause pancreatitis, but are attributed to a number of infectious diseases such as toxoplasmosis, FIP, and FIV. Both dogs and cats with diabetes mellitus appear to be prone to pancreatitis. is more common in dogs and was once thought to be uncommon in cats. Although it is now thought that acute pancreatitis is actually more common and often missed in cats suffering from the disease. Cats frequently have more subtle and nonspecific clinical signs such as lethargy and anorexia. Chronic pancreatitis is seen more often in cats than in dogs

Diagnosis Diagnosis of pancreatitis is reliant on a combination of clinical signs, laboratory findings, and imaging. Clinical signs in dogs include vomiting, abdominal pain, depression, dehydration, anorexia, fever, and diarrhea. Severe cases may present with petechiation, icterus, ascites, and even . In some dogs an abdominal mass may be palpated. In cats the common signs include anorexia, lethargy, dehydration, and weight loss with vomiting occurring in less than 50% of cases. Laboratory finds are nonspecific and quite varied. Some dogs present with a mild neutrophilia or severe leukocytosis with or without a left shift, anemia and neutropenia, or thrombocytopenia. Azotemia, increased liver values, lipemia, , hypoproteinemia, hypercalcemia, and metabolic acidosis may also be seen. Elevations in amylase and lipase have been considered indications of pancreatitis, however these enzymes may be normal in dogs with pancreatitis and elevated in patients not suffering from the disease. Canine and feline pancreatic lipase immunoreactivity (cPLI and fPLI, respectively) are enzyme-linked immunoassays that were developed to measure species specific pancreatic lipase activity. They are considered the most reliable indicators of acute pancreatitis; both can be affected by the severity of the disease. Abdominal radiographs may be useful in the diagnosis of acute pancreatitis, however radiographs with non-specific findings are not unusual in patients with acute pancreatitis. Abdominal ultrasound is a more sensitive method of imaging and is often used in the diagnosis of pancreatitis in dogs and cats. An enlarged hypoechoic pancreas is suggestive of edema, hemorrhage or necrosis commonly seen in patients with acute pancreatitis. Other abnormalities such as peritoneal fluid, abscesses, and dilation of the pancreatic or biliary ducts may also be seen. Unfortunately, the sensitivity of ultrasonography when used alone to diagnose acute pancreatitis is generally low, with sensitivities ranging from 11 to 67% in cats and 68% in dogs

Treatment Abdominal pain, which may be severe, is common in patients with pancreatitis and should be addressed with analgesia. Fentanyl and other opioids are commonly used to improve patient comfort often in combination with low-dose ketamine and lidocaine in a constant rate infusion. Antiemetics such as maropitant, dolasetron, and ondansetron are recommended to reduce nausea in patients suffering from pancreatitis. Frequent aspiration of stomach contents is also recommended to reduce patient discomfort, nausea, gastric distention, regurgitation and decrease the risk for aspiration pneumonia. Water intake is important in order to avoid or correct dehydration, and parental fluid therapy may be required. Electrolyte and acid base disturbances, if any, should be corrected before beginning nutritional support. Fasting these patients until clinical signs resolve to “rest the pancreases” and/or providing parenteral nutrition was long considered the appropriate nutritional management. However, premature intracellular activation of proteolytic enzymes is now thought to be the disease trigger rather than pancreatic stimulation. Studies in humans and rodents have shown that exocrine pancreatic secretion actually decreases during pancreatitis. Fasting to decrease pancreatic stimulation is therefore unnecessary and may be contraindicated. Withholding enteral nutrition decreases intestinal motility, compromises intestinal blood flow, and may cause intestinal villus atrophy. Prolonged fasting may also lead to abnormal internal bacterial flora and gastrointestinal barrier function. Patients with acute pancreatitis may have been anorexic for a number of days prior to presentation; fasting these patients, especially for multiple days, is not recommended. In dogs and cats enteral feeding is thought to prevent mucosal atrophy and therefore may reduce the risk of bacterial translocation and septic complications. 870

Studies in people have shown improved survival rates in patients feed via tubes, shorter hospitals stays, and lower medical costs compared to those receiving parenteral nutrition. In veterinary patients, jejunostomy tubes are generally placed either endoscopically, fluoroscopically or surgically and are at risk of becoming dislodged after placement. Nasogastric tubes are more commonly used in veterinary medicine. These are less expensive and easier to place than j-tubes, and are often well tolerated in dogs and cats. Multiple human studies comparing nasogastric tube feeding to nasojejunal feeding have shown no significant difference in mortality rate, length of hospitalization, or infectious complication rates. The International Consensus Guidelines for Nutrition Therapy in Pancreatitis guidelines on nutrition therapy for acute pancreatitis, states that “postpyloric feeding is not required and support the use of NG feeding, although consensus agreement was not reached”. Many experts recommend NG tube feeding as the initial feeding method for patients that are unwilling to eat especially for patients not stable enough for general anesthesia or those not anticipated to require long-term assisted feeding. Enteral feeding, when started early, may help decrease vomiting and improve gastrointestinal motility. The goal of trickle feeding a liquid diet to these patients is often not to attempt to meet their resting energy requirements (RER), but rather to test to see if the patient can tolerate enteral feeding and to provide nutrition to the cells of the interstitial lining. Some clinicians may prefer nasoesphageal tubes over nasogastric tubes because of concerns NG tubes may increase the risk of regurgitation and gastroesophageal reflux due to the irritation caused by the tube crossing the esophageal sphincter. A 2013 study compared the complication rates of these two tube types and found there to be no significant difference. NG tubes should be considered in patients with motility problems as they allow for liquid stomach contents to be aspirated. These patients often feel better after aspiration of liquid stomach contents; some may even begin to eat voluntary. NG and NE tubes require vigilant ; if they should become dislodged they may cause aspiration pneumonia. Only liquid veterinary diets should be used for feeding through NG and NE tubes. CliniCare® Canine/Feline Liquid Diet, which contains 1 Kcal/ml, is a good option. Emeraid® Intensive Care HDN™ Feline and Emeraid® Intensive Care™ HDN Canine are powdered formulas which are mixed with water and are also a good option. The volume of water added can be varied dependent on the diameter of the feeding tube, however the caloric density is reduced as the volume of water is increased. Trickle feeding via constant rate infusion (CRI) is most often used for hospitalized patients, although these tubes may also be used for bolus feedings and to administer oral liquid medications. Tablets should not be crushed and administered via these small tubes. A number of liquid diets designed for people are also available. These diets are typically less expensive then veterinary liquid diets however are nutritionally inadequate and some may contain ingredients that are inappropriate for dogs and cats. These human diets are especially inappropriate for cats as they are too low in protein, taurine, and arginine. Esophagostomy (E) tubes are a good option for patients that are healthy enough for a short anesthetic procedure. They are relatively easy to place and may be used in cats and dogs. They can be used by clients at home for longer term nutritional support if necessary and allow for a wider variety of canned diets to be used when blenderized with water. Medications may also be crushed and administer via E-tubes. Gastrostomy tubes are also an option for long term nutritional support. Percutaneous Endoscopic Gastrostomy Tubes (PEG) are a good option when used for long term case. Clients are able to administer bolus feedings and medications at home using this method. General anesthesia is required and placement via an endoscope is recommended, although these are sometimes placed “blind”. Feeding via the PEG tube can begin as early as 12 hours post-placement, however waiting 24 hours is usually recommended. Once a PEG tube is placed it should not be removed for 10-14 days to prevent leakage of gastric contents into the abdominal cavity. This type of feeding tube can remain in place for months and maybe replaced with a low profile tube for longer-term use. The incision site may require superficial cleaning for a few days post-insertion. These tubes allow for a wide variety of diet options when blenderized with water. Medications may also be crushed and administered via PEG tubes.

Parenteral nutrition Parenteral nutrition (PN) is generally reserved for patients with severe acute pancreatitis that cannot tolerate enteral feeding. Parenteral nutrition must be compounded and may not be readily available to many veterinary hospitals other than larger referral hospitals. Commercially available PN solutions for people are not designed to meet the needs of animals and may not provide adequate nutritional support. In some cases premade glucose and solution may be used short-term until the patient is stable enough to undergo general anesthesia for feeding tube placement or begins to eat on its own. The use of PN in veterinary patients has been associated with a risk of infection and intestinal atrophy, with subsequent risk of bacterial translocation, increased rate of ; and metabolic complications such as hyperglycemia, blood electrolyte abnormalities, and hyperlipidemia. Aseptic technique is required and extreme care should be taken with the handling and administration of parenteral nutrition; if contaminated PN can become an excellent growth medium for bacteria. A study by Jensen and Chan (2014) showed patients receiving PN that were also trickle fed had a higher survival rate than those receiving PN only. Due to the risk of potential complications, the difficulty in obtaining and the high cost of providing parenteral nutrition, enternal feeding remains the preferred method for most acute pancreatitis patients. If PN is used, the recommendation is to begin trickle feeding as soon as the patient will tolerate it and gradually increase the enteral feeding.

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Dietary considerations A highly digestible diet, which is not high in fat, designed for patients with gastrointestinal disease is generally recommended for patients with pancreatitis. In some dogs breeds hypertriglyceridemia has been shown to be a predisposing factor. For obese and/or hypertriglyceridemic dogs, diets with a fat content of ≤10% on dry matter basis (DMB) are recommended to manage pancreatitis. Non-obese dogs and those that are not hypertriglyceridemic, diets with a fat content of ≤15% DMB are recommended. The recommended protein level for dogs with pancreatitis is 15 to 30% DMB. Cats have a higher dietary fat requirement than dogs and can also digest and use dietary fat more effectively. This makes cats more susceptible to malnutrition and lean muscle loss during periods of anoxia and starvation. Insignificant levels of the amino acids arginine and methionine may contribute to the development of hepatic lipidosis in cats. For obese and/or hypertriglyceridemic cats, diets with a fat content of ≤10% on dry matter basis (DMB) are recommended to manage pancreatitis. For non-obese cats and those that are not hypertriglyceridemic, diets with a fat content of ≤25% DMB are recommended. The recommended protein level for dogs with pancreatitis is 30 to 40% DMB. Cats with chronic pancreatitis may develop cobalamin deficiency. Subcutaneous or intramuscular injections of B12 are recommended, given weekly for the first month, and then continued every 2 to 4 weeks.

Energy requirements Resting energy requirement (RER) represents the energy requirement for a normal animal, which is not fasted, and is at rest under thermo-neutral conditions. The equation 70 x (body weight in kg) ¾ is used to calculate RER. The general recommendation is to begin feeding pancreatitis patients 1/3 or less of the patient’s total RER for the first 12 hours and, if well tolerated, to gradually increase this amount every 12 hours until full RER is reached. If at any time the patient vomits, discontinuing feeding until vomiting has resolved, reducing the volume when feeding is resumed, and increasing the volume more slowly is recommended. In the past, an illness factor was often added to the RER when feeding critically ill, however this practice is no longer recommended. It has been shown that excessive nutrition during times of illness may increase the risk of hyperglycemia and other metabolic complications.

References Cook and Levine. Risk factors associated with acute pancreatitis in dogs: 101 cases (1985–1990). Journal of the American Veterinary Medical Association 1993. Jensen and Chan. Nutritional management of acute pancreatitis in dogs and cats. Journal of Veterinary Emergency and Critical Care, 2014 Mirtallo, Forbes, McClave, etal. International Consensus Guidelines for Nutrition Therapy in Pancreatitis. Journal of Parenteral and Enteral Nutrition 2012. Yu MK, Freeman LM, Heinze CR. Comparison of complication rates in dogs with nasoesophageal versus nasogastric feeding tubes. Journal of Veterinary Emergency Critica Care 2013.

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Taking the Mystery Out of Pet Food Labels Ed Carlson, CVT, VTS (Nutrition) IVG Hospitals, Inc. Woburn, MA

Reading and understanding pet food labels is an important skill for all veterinary technicians to have. Clients often have questions about the food they are feeding their pet or which food would be best for their pet. Veterinary technicians are ideally suited to educate clients and make nutritional recommendations.

Pet food governing agencies and organizations Having a basic knowledge of the agencies and organizations that regulate pet foods and pet food labels is the first step to understanding pet food labels. The Association of American Feed Control Officials (AAFCO) The Association of American Feed Control Officials (AAFCO) is a private organization but is not a regulatory body. All members of the AAFCO must be state or federal government officials. Pet food companies, pet food trade organizations (the Pet Food Institute for example) and professional organizations (such as the American College of Veterinary Nutrition) cannot be members, but may serve in an advisory capacity to AAFCO committees and investigations. The AAFCO develops model laws and regulations which are often adapted by states. Member government agencies often request assistance from AAFCO when revising existing or developing new regulations and laws. AAFCO also publishes ingredient definitions, official terms, pet food labeling information and standards for pet food testing. AAFCO established the current standards for dog and cat food nutrient profiles including the minimum standards for adult maintenance, growth, and reproduction profiles for both dogs and cats. The organization also set maximum levels for some nutrients in dog and cat foods. Testing protocols for evaluating metabolizable energy and feeding trail guidelines are also published by AAFCO. Many, but not all, states follow model bills and regulations for pet foods established by AAFCO. The Center of Veterinary Medicine (CVM) The Center of Veterinary Medicine (CVM), a division of the Food and Drug Administration (FDA), regulates pet food in cooperation with individual states. The FDA is responsible for regulating health claims, ensures food safety, approves food additives, as well as the specifics of some label requirements. The CVM regulates health claims made on pet food labels and product literature. Feed control officials in each state inspect manufacturing facilities and enforce these regulations. Pet food labels are legal documents and governed by the laws of the country the product will be sold in. All pet foods must meet the FDA’s requirements and the requirements of the state they are sold in. United States Department of Agriculture (USDA) The United States Department of Agriculture (USDA) inspects and regulates animal research facilities and may make unannounced inspections of these facilities. The USDA inspects ingredients used in pet foods to ensure proper handling and is responsible to ensure pet foods are labeled in a manner that makes it clear the food is intended for animals and not human consumption. National Research Council (NRC) The National Research Council (NRC) is a non-profit, non-government organization that evaluates research conducted by other groups and individuals. The NRC published “Nutrient Requirements of Domestic Animals” in 2006 that, in the United States, has been replaced with the AAFCO guidelines. However, these guidelines are still in use in some other countries. Pet Food Institute (PFI) The Pet Food Institute (PFI) is a national trade organization whose members include pet food manufacturers and pet food related suppliers. They represent the pet food industry, at the state and federal levels, before regulatory and legislative bodies.

Pet food label requirements All pet food labels are required to have two main sections, each have legally required components: 1.) the principal display panel, and 2.) the information panel. The FDA definition of the principal display panel is “the part of the label that is most likely to be displayed, presented, shown, or examined under customary conditions of display for retail sale”. The information panel is defined by the FDA as “that part of the label immediately contiguous and to the right of the principal display panel”.

Principal display panel The principal display panel must contain the product name, the species the food is designed for, and the net weight of the food contained in the package. There are specific requirements governing how products are named. If the name of a food is “Chicken for cats”, the food must contain 70% or more chicken as fed. “Chicken dinner”, “chicken platter”, “chicken entrée” must be 25% or more chicken total weight. “With chicken” must be at least 3% chicken. “Chicken flavor” is usually less than 3% chicken. Canned foods may not be greater than 78% moisture. However, foods with “chicken in gravy” or “in sauce” in their name are allowed to have moisture of 78% or more.

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The principal display panel may also, and normally does, include the manufactures name and the brand name. A product vignette (picture/likeness) may also appear on the label. If a vignette is included, it must not misrepresent the product. Nutritional claims, such as “complete and balanced”, may appear on the principal display panel. All such claims are regulated and are discussed in the nutritional adequacy statement section below. Bursts and flags highlighting improvements, new products, or ingredient changes are allowed. However, the length of time this information is allowed to appear on the label is limited.

The information panel The information panel must include the ingredient statement. Ingredients must be listed in descending order by weight and only standard AAFCO terms may be used. A guaranteed analysis must be included listing the minimum percentages of crude protein and crude fat and the maximum percentages of crude fiber and moisture. Other nutrients are not required to be listed unless they are highlighted on the label. Nutrients not listed in the AAFCO Nutrient Profile must indicate “not recognized as an essential nutrient by the AAFCO Dog or Cat Food Nutrient Profiles.” Ash content is not required, but maximum ash guarantee is allowed. Cat food labels may state “low ” if the maximum level is included and if the food contains less than 0.12% on a dry matter basis and less than 25 mg per 100 kcal metabolizable energy. A nutritional adequacy statement must also be listed on all pet food labels except for treats and supplements. Claims such as “complete and balanced” must be substantiated by one of the three methods AAFCO allows to substantiate such claims: 1.) the formulation method, 2.) the feeding trial method, and 3.) the family method. Dog and cat pet food producers that use the formula method to substantiate the claim a food is complete and balanced must formulate the food to meet AAFCO Food Nutrient Profiles using standard nutrient information about the ingredients the food contains or by having the product analyzed. The formula method does not ensure the availability of nutrients in the food or that the food is palatable. However, it is the easiest, least time consuming, and least expensive method. Foods using this method of validation must state it is “formulated to meet the nutritional levels established by the AAFCO Dog or Cat Food Nutrient Profile for (the life stage it was tested for)” on the product label. The feeding trial method requires pet food companies to conduct feeding trials, using minimum standards established by AAFCO. All animals in the study are examined by a veterinarian at the start of the study and again when the feeding trial is completed. Participants are also required to have minimum baseline labwork preformed, and body weights recorded weekly. This method may be used to validate that the food meets the requirements for growth, gestation and lactation, adult maintenance, and/or all life stages. The heath of the dam at the end of the study and the size and health of the litter are taken into consideration with the gestation and lactation trials. Growth feeding trials must be conducted for a minimum of 10 weeks. The “all life stages” claim may be used when the offspring of a gestation and lactation feeding trial complete a growth feeding trial. Feeding trials for adult maintenance claims must be conducted for at least 26 weeks. The majority of nutritional deficiencies, if any, should be detected using this method of validation. However, nutrient excesses might not be evident during this timeframe. “Animal feeding tests using AAFCO procedures substantiate that (name of food) provides complete and balanced nutrition for (the life stage it was tested for)” is listed on the label of foods that have passed feeding trials. The feeding trial method is much more expensive and time consuming to conduct. It is generally considered the preferred method to substantiate nutritional adequacy claims. The less common method of substantiating a food claim is the family method. Foods using this method must be in the same product line and be the same processing type (dry, canned, etc.) as a food tested using the feeding trial method. When analyzed, crude protein, calcium, phosphorus, zinc, lysine, and thiamin (as well as taurine and potassium for cat foods) must meet the levels of the food validated by feeding trials or the minimums established in the AAFCO Dog or Cat Food Nutrient Profiles for all nutrients. Products using this method must state “provides complete and balanced nutrition for (life stage), and is comparable in nutritional adequacy to a product which has been substantiated using AAFCO feeding test” on the label. Treats and supplements are not required to include a nutritional adequacy statement on their label. Foods that do not meet AAFCO standards must be labeled “This product is intended for intermittent or supplemental feeding only.” Veterinary therapeutic diets should be labeled “use only as directed by your veterinarian.” These products must also list an AAFCO life stage nutritional adequacy statement or “this product is intended for intermittent or supplemental feeding only” on the label. Feeding guidelines must be included on all dog and cat food labels, except veterinary therapeutic diets. These guidelines must be listed in common terms (for example a x pound cat, x cups of diet). These are only guidelines which are generally based on standard maintenance energy requirement (MER) equations with a safety margin. Actual amounts to feed should be calculated using one of several established methods and adjusted based on the pets body condition. However, it is important to note that pets consuming less than 80% of the recommended amount for their ideal weight may be consuming inadequate nutrients. These pets should be transitioned to a less caloric dense food. The calorie content of dog and cat foods is not required to be listed on the label unless a claim of “light” or “less calorie” is listed on the label.

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Manufacturer, distributor, or importer name and address must also be included. The company’s phone number and website are not required to be listed on the label, but may be included. A company that manufactures and distributes dog and cat food may state “manufactured by” on the label. Some companies have their foods manufactured by another company; these foods must state “manufactured for”, “imported by”, “distributed for” on the label. Foods not made in the United States must state “product of” on the label. Universal Product Code (UPC), batch numbers, date of manufacture, and best used by date may also be included on the information panel.

References Small Animal Clinical Nutrition, 5th Edition, Hand, Tharcher, Remillard, Roudebush, Novomy

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Insights into Anesthetic Drugs Kristen Cooley, BA, CVT, VTS (Anesthesia) University of Wisconsin Madison, WI

Anesthesia carries with it a certain degree of risk and there is no single best way to anesthetize animals. Appropriate drug selection is important and largely dependent on the patient’s physical status, temperament, type of procedure, present and anticipated pain, familiarity of drugs available and cost.

One size does not fit all It is generally not recommended to use pre-mixed drug cocktails like BAG or kitty magic. These cocktails do not allow for tailoring of the protocol to the specific temperament of the patient and often result in inappropriate dosing. There is also room for human error in mixing up large volumes of drugs, recording controlled substances and breaks in aseptic technique when pulling from a multi-dose vial. Best practice includes accurately drawing up each drug individually and then mixing them together for delivery. Designing an anesthetic protocol is easy if you remember PIMP, preanesthetics, induction, maintenance and pain management.

Pre-anesthetics and balanced anesthesia Pre-anesthetics are an essential component to successful anesthesia. Pre-anesthetics help to calm and sedate anxious, frightened or fractious patients. It streamlines restraint and decreases patient and staff stress. Reduces the necessary dose of induction drug, helps to decrease the amount of inhalant needed for maintenance of anesthesia, promotes smoother inductions and calmer recoveries along with an easier to manage maintenance stage of anesthesia. Pre-emptive pain management, or giving an analgesic in anticipation of pain, should be part of the preanesthetic period. Balanced techniques along with pre-emptive analgesia can make post-operative pain easier to manage. Balanced anesthesia is the concurrent administration of smaller quantities of multiple drugs allowing them to work synergistically- combined drug effectiveness is greater than the sum of each part- which allows for the use of less of each drug minimizing side effects and maximizing therapeutic benefit.

Pharmacokinetics and pharmacodynamics Understanding anesthetic drugs requires an appreciation of each drug’s pharmacokinetics and pharmacodynamics. Pharmacokinetics refers to the effect the body has on the drug and pharmacodynamics refers to the effect the drug has on the body. Drugs enter the body via the bloodstream and bind to specific receptors located in target organs and tissues to exert specific effects- for anesthetics these effects are usually central nervous system depression or stimulation. Agonists are drugs that bind to and stimulate a specific receptor found in target tissues. Antagonists bind to but do not stimulate receptors- most antagonists competitively bind to receptors and displace agonists effectively ‘reversing’ the action of the initial drug. A partial agonist is a drug that only partially stimulates a receptor and an agonist-antagonist binds to more than one receptor, agonizing one and antagonizing another. Benzodiazepines like diazepam and midazolam are sedatives that work by increasing the activity of an inhibitory neurotransmitter- gamm-aminobutyric acid or GABA. This class of drugs is used for anti-anxiety and calming in ill or geriatric animals, skeletal muscle relaxation, appetite stimulation and as an anticonvulsant. Benzodiazepines do not provide any analgesia and cause very minimal (if any) cardiovascular and respiratory depression. They have the tendency to decrease inhibition in young, healthy animals causing paradoxical excitement especially when given alone. Benzodiazepines are reversible with the drug flumazenil. Onset time is rapid and duration of action is 1-3 hours. Diazepam: propylene glycol based, for IV use only Midazolam: water based, can be given IM, SQ or IV Phenothiazines like acepromazine or ‘ace’, is a tranquilizer often used as a preanesthetic in cats, dogs and horses. Acepromazine is an alpha-1 adrenergic and dopaminergic receptor antagonist that causes dose dependent sedation and a generalized disinterest in surroundings. It has no analgesic properties and it can mask the signs of pain without alleviating them. Ace can cause peripheral vasodilation that can negatively affect blood pressure and body temperature. It also has antiemetic and antihistamine effects. Onset time is around 15 minutes with peak effect at 30 minutes. Duration of action is variable and dose-dependent and can last 4-8 hours in small animals. Alpha-2 adrenergic agonists provide sedation, muscle relaxation and analgesia. This class includes the drugs detomidine, dexmedetomidine and xylazine which are commonly used in both large and small animals. Dexmedetomidine is more specific for the alpha-2 receptor making the side effects associated with this drug class less prominent compared to xylazine and therefore safer for our small animal patients. Sedation and analgesia is dose dependent as is the duration of action. Peripheral vasoconstriction leads to pale mucous membranes and a reflex bradycardia. Vomiting and increase urine production are not uncommon. Some animals may be refractory to the drug. Co-administer with an opioid and allow patients to sedate in a quite place to decrease stimulation. Alpha-2 agonists are fully reversible with atipamezole (dexmedetomidine) or yohimbine (xylazine). The volume of reversal given should be

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the same as the volume of drug given previously. Dexmedetomidine: onset time is 5-15 minutes IV, 15-30 minutes IM. Duration of action is around 90 minutes. Opioids provide analgesia by binding to specific receptors located in the brainstem and spinal cord. Some opioid receptors can also be found in peripheral tissues. Opioids don’t remove pain; they raise the threshold making pain more tolerable. There are two main types of opioid receptors, kappa and mu. Pain is mediated by mu receptors in mammals and kappa in birds. There is some evidence to suggest that kappa receptors exist in higher numbers in the gut compared to the peripheral tissues in mammals allowing kappa agonists to provide good visceral analgesia. Pure mu agonist opioids include morphine, hydromorphone, oxymorphone, fentanyl and methadone. This group of drugs fully bind to the mu receptor and are effective at providing analgesia. They can also cause sedation, especially in geriatric, pediatric or debilitated animals. Pure mu agonist opioids cause minimal cardiovascular depression and dose dependent respiratory depression by increasing the resting partial pressure of carbon dioxide or PaCO2. Bradycardia from vagal stimulation, vomiting from direct stimulation of the chemoreceptor trigger zone (CTZ), urine retention from decrease sensation and urge, antitussive properties and resetting of thermoregulation are not uncommon side effects of this drug class. Morphine Histamine release when given IV, poor oral bioavailability, vomiting is common, high solubility make it a great for epidural use (preservative free formulation is recommended). Duration of action is 4-6 hours. Hydromorphone/oxymorphone Less vomiting compared to morphine, no histamine release IV, hydromophone may cause hyperthermia in cats. Duration of action is 2-3 hours. IV fentanyl Very potent synthetic opioid, 3-8 minute onset time IV with a short duration of 20-30 minutes. Given as a constant rate infusion (CRI). Fentanyl patch Variable absorption that may not provide adequate analgesia if used as a sole means of analgesia. Takes 12-18 hours to reach therapeutic plasma levels and can potentially last for 3 days. Dose accordingly! Methadone Pure mu agonist and NMDA antagonist (helps prevent wind-up pain by blocking n-methyl d-aspartate). Good analgesia and less sedation compared to morphine. Duration of action is 3-4 hours. Agonsit/antagonist drugs stimulate one receptor while blocking another. Drugs like butorphanol and nalbuphine stimulate the kappa receptor while blocking the mu receptor making them only effective at treating mild pain in mammals. Because they block the mu receptor they can be used to reverse any unwanted effects of a pure mu agonist opioid while maintaining some analgesia. Butorphanol Mild analgesic with a ceiling effect (more drug does not equal more analgesia), short duration of action lasting 45 minutes- sedation may last longer, controlled as schedule IV Nalbuphine Mild analgesic, short duration of action lasting only 30 minutes, not a controlled substance A partial agonist opioid is a drug that does not fully bind to the mu receptor making it less effective than a pure mu agonist like morphine. Partial agonists are drugs that only partially bind to the mu receptor exerting an effect that is not as great Buprenorphine Very high affinity for the mu receptor making the use of subsequent opioids ineffective until buprenorphine has worn off. Slow onset of action taking it nearly 45 minutes to provide pain control but long duration of action 6-8 hours, great transmucosal absorption in the cat but only about 30% bioavailable transmucosally in the dog, class III controlled substance Sustained release buprenorphine (SR) is not an FDA approved product but is available through a compounding . It is given SQ and has been shown to provide up to 72 hours of analgesia. Reversal is difficult and may require hospitalization. Simbadol High potency buprenorphine (1.8 mg/ml) dosed at 0.24 mg/kg and FDA approved for use in cats. Provides 24 hours of analgesia and can be q24 for up to 3 days. SubQ ONLY. Opioid antagonists completely reverse the effects (analgesia, sedation and cardiopulmonary depression) of all circulating opioids including endogenous ones. These drugs should only be used in the face of an absolute opioid overdose because their use removes ALL analgesia along with any other effects. An acute awareness of pain can lead to catecholamine release from sympathetic stimulation which may result in cardiac arrhythmias, hypertension and possibly death. Redosing may be necessary due to the short duration of action of naloxone compared to most opioids.  Naloxone: onset 1-2 minutes IV, 5 minutes IM, duration of action 30-60 minutes  Nalmefene: onset 1-2 minutes IV, 5 minutes IM, duration of action 1-2 hours

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Anticholinergics are sometimes used in preanesthetic combination to prevent bradycardia and decrease salivary secretions. Drug class effects include secretion reduction, bronchodilation, arrhythmias (glyco is less arrythmogenic), thickening of respiratory secretions, and inhibition of intestinal peristalsis. Conservative use of anticholinergics is recommended and their use should never be a substitute for diligent monitoring. Induction Drugs consist of injectable agents that allow the anesthetist to induce anesthesia quickly and to secure an airway. Injectable agents provide a safer, less stressful alternative to ‘gassing’ or ‘boxing’ down a patient. It is also less expensive, faster, with less waste/pollution and more control. All injectable anesthetics depress some vital organ function making the use of preanesthetics and subsequent lower doses essential. Dissociative anesthetics are also referred to as cyclohexamines- these drugs produce a dissociated state along with sympathetic stimulation. Increases in cerebral blood flow and intracranial and intra-ocular pressure, CNS stimulation, primary cardiovascular depression with indirect sympathetic stimulation leading to increased heart rate, blood pressure and cardiac output. Sub-anesthetic doses of ketamine (and possibly Telazol) act as NMDA antagonists blocking central sensitization (wind-up pain) in the dorsal horn of the spinal cord. They are not analgesics in and of themselves and should not be used as a sole means of pain control however; ketamine is a great adjunctive medication contributing to a balanced approach to analgesia. Ketamine and Telazol are contraindicated in in patients that are sympathetically spent- severe trauma, stress, shock etc. This is due to the fact that only the direct cardiovascular effects will be appreciated. Not recommended for use in patients with cardiovascular disease, head trauma, intracranial masses, glaucoma, corneal ulcers, pheochromocytoma, hyperthyroidism. Ketamine: dissociative anesthetic that causes muscle rigidity when used alone, commonly coupled with a benzodiazepine for induction. Not recommended for use with an anticholinergic as significant tachycardias can ensue, hepatic metabolism in the dog, renal excretion in the cat. Telazol: Combination of a dissociative and a benzodiazepine. Tiletamine and zolazepam mixture, must be reconstituted with , use within 4 days if stored at room temp or two weeks if refrigerated. Propofol and Propofol-28: Propofol is an ultra-short acting non-barbiturate induction drug with rapid metabolic clearance. Ninety seconds to peak effect and 5 minutes to redistribute, non-cumulative, administer slowly and steady to avoid over-dosing. Propofol has the potential to cause profound cardiovascular and respiratory depression and should be used cautiously. IV injection can be painful and muscle twitching and seizure-like activity has been reported. Repeated dosing is not recommended in cats as oxidative injury to red blood cells may result. Drug can be re-dosed intraoperatively at 1-2 mg/kg if patient becomes light. Pre-oxygenation is also recommended. Propofol-28 contains benzyl alcohol as a preservative giving it a 28-day shelf life. Regular propofol should be discarded 6-8 hours after opening. Etomidate: Etomidate has little to no negative effect on the cardiovascular system- ideal induction drug for hemodynamically unstable patients. It may have brain protective properties after global ischemia, and inhibits steroid production by the adrenal glands for 3-6 hours after administration- not recommended in patients with hypoadrenalcortism. Vomiting and retching is common with underdosing and etomidate can be painful IV because it is based in propylene glycol. This drug is also expensive. Alfaxalone: Alfaxalone is a neuroactive steroid substance that is used extensively in the UK, Australia, Europe and Canada. It produces hypnosis with reasonable muscle relaxation and a decrease in cerebral blood flow and cerebral oxygen demand. Dose dependent hypotension may be seen initially due to myocardial depression and peripheral vasodilation but the effects are often offset by the reflex tachycardia. Respiratory depression associated with the use of alfaxalone is dose dependent; the drug is non-cumulative and approved for IV use only. IM chemical restraint is off-label and works better for cats vs. dogs (very short duration of action). Alfaxalone is not an analgesic, it does not contain preservatives and should be discarded 6 hours after opening. Maintenance of anesthesia is often achieved through the use of inhalant anesthetics. Inhalants are potent vasodilators and cause dose-dependent hypotension and respiratory depression. The two most common inhalants used in veterinary medicine are isoflurane and sevoflurane. The minimum alveolar concentration or MAC is the potency of an inhalant. MAC-50 is the amount of inhalant needed to keep 50% of patients non-responsive to surgical stimulation. MAC-95 or surgical MAC is the amount of inhalant needed to keep 95% of patients non-responsive to surgical stimulation and is calculated by multiplying MAC-50 for the species by 1.5. It is important to note that respiratory arrest can occur at 2 x MAC so proper dosing is essential to safety. MAC studies are done on patients who have not been given pre-anesthetics. The use of pre-anesthetics decreases the amount of inhalant necessary thereby reducing MAC. Isoflurane: MAC is 1.3% in dogs and 1.6% in cats, low blood-gas solubility (rapid induction and recovery), 0.2% metabolized in the body. Sevoflurane: MAC is 2.3% in dogs and 2.6% in cats (sevo is less potent and requires higher vaporizer settings to maintain anesthesia), lower blood-gas solubility, 3% metabolized in the body. Pain Management is an important part of the anesthetic protocol and balanced techniques should be employed whenever possible. In addition to opioids and alpha-2 agonists, the flowing drugs should augment the pain management protocol.

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Non-steroidal anti-inflammatory drugs (NSAIDS) NSAIDS (Non-steroidal anti-inflammatory drugs) block the production of specific prostaglandins by binding and inhibiting the cyclooxygenase (COX) enzyme. COX enzymes (COX-1 and COX-2) also have important homeostatic functions. COX-1 mediates prostaglandins responsible for renal and GI blood flow and platelet integrity and COX-2 mediates prostaglandins responsible for inflammation, pain, edema, fever as well as other homeostatic functions. NSAIDS should be avoided in animals with renal or hepatic dysfunction, coagulopathies, GI disorders, shock, hypotension/hypovolemia and they are not recommended for use in combination with corticosteroids. Lidocaine Lidocaine is a local-anesthetic and anti-arrhythmic agent with a rapid onset and short duration of action. Lidocaine is a prokinetic that enhances gut motility and help prevent ileus. It has MAC sparing effects when given as a constant rate infusion, a loading dose must be given prior to starting a CRI to achieve blood levels. Cats are sensitive to lidocaine and care should be taken when this drug is used. MLK (Morpine, Lidocaine, Ketamine) Drugs are combined into a bag of IV fluids and delivered at a surgical rate. Loading dose of each drug is required to achieve therapeutic levels. Tramadol An oral medication that has weak mu receptor effects along with norepinephrine and serotonin reuptake inhibition. Tramadol works well with NSAIDS as post-operative pain management. Gabapentin is effective at reducing hyperalgesia and allodynia associated with neuropathic pain and central sensitization as well as chronic and malignant pain. Gabapentin is not an analgesic but an adjunctive medication that allows true analgesics to work better by calming down the nervous system- gabapentin should be used in conjunction with NSAIDS and/or tramadol for best results. Amantadine is an NMDA antagonist and analgesic adjunctive medication. It is good at reducing central sensitization. Amantadine is excreted almost unchanged in the urine- reduce doses in the renal patient.

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Lights Out! The Anesthetic Induction Period Kristen Cooley, BA, CVT, VTS (Anesthesia) University of Wisconsin Madison, WI

Anesthesia is the reversible loss of sensation as a result of pharmacological agents that may affect all or part of the body. There are differing levels of anesthesia that range from conscious sedation for minor procedures to deep general anesthesia for more invasive techniques. Anesthesia induction precedes general anesthesia that produces unconsciousness and through balanced techniques also includes analgesia, muscle relaxation and amnesia.

Balanced anesthesia Balanced anesthetic protocols incorporate multiple drugs and techniques from different classes to achieve a desired goal. Animals are prepared for anesthesia by performing a thorough patient evaluation, choosing adequate premedication, placing an IV catheter, initiating a controlled induction and securing the airway. The equipment and drugs used in the induction period vary depending on the patient’s health and temperament as well as the procedure being performed. The anesthetist’s role is to gather this information and in consultation with a veterinarian, develop a suitable induction plan for his/her patient. Anesthesia induction The careful administration of appropriate agents to bring about unconsciousness and to help facilitate endotracheal intubation or securing of the airway. The induction period begins with premedication administration and ends when all monitors are connected and the patient is on a maintenance level of anesthesia.

Getting ready Once the patient has been premedicated, time is needed for the drug to take effect. The amount of time depends on the route and type of drug as well as the temperament of the patient and the environment. IV premeds require 1-2 minutes where as an IM injection may take up to 15 minutes to take effect. Anxious patients will often take longer to sedate and patients premedicated in a loud or otherwise stressful/active room will also be on edge and take longer to sedate. Best practice is to premed and then put the patient in a quite and dark room. Periodic monitoring of patients while sedating is essential. The period of time between premeds and induction is an ideal time to gather supplies and leak test equipment. For example one could:  Set up and pressure test anesthesia machine  Gather IV catheter supplies  Choose three endotracheal tubes and check each cuff for leaks  Corral monitoring equipment and check that it is working properly  Plug in supplemental heating device and warm it up  Fill out anesthesia monitoring sheet with patient information  Calculate, check and draw up induction drugs  Calculate fluid rate and set up fluids  Formulate an emergency plan and calculate emergency drugs

IV All patients undergoing anesthesia should have an IV catheter placed. IV access is essential when performing successful anesthesia because having a catheter facilitates the delivery of IV anesthetics, avoids potentially harmful perivascular drug administration and provides access to rapid drug/fluid administration in emergency situations. IV fluid therapy in anesthetized dogs and cats is recommended to maintain , to help correct hypovolemia caused by the vasodilitory effects of anesthetic drugs, to help replace insensible fluid losses common in the surgical patient. IV catheter size is important because it influences the drug delivery rate and may cause unwanted patient side effects. For example, a small gauge catheter is easy to place and produces less inflammation; however, it may be difficult to deliver highly viscous drugs rapidly or with ease. The IV fluid administration rate is also limited by the internal diameter of the catheter. A larger gauge catheter may be more difficult to place but will deliver drugs and fluids with ease. It can cause phlebitis due to the constant contact it makes with the vessel wall. As a general guide, 22 gauge catheters work well in most cats and 20 gauge catheters work well in most dogs. Gauge is a decending scale; large numbers correlate to small diameters (20 gauge is smaller than 10 gauge). French is ascending where large numbers correlate with large diameters (20 French is larger than 10 French). Note: Intact animals, male and female, have tougher skin and often require a larger sized catheter or a ‘pilot’ hole to be made with a needle prior to catheter insertion. This hole prevents burring of the cannula from pushing it through tough tissue. To make a pilot

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hole, choose a needle one size larger than the catheter you wish to place. Tent up the skin and poke a hole through the skin only. Then, use that hole to introduce the catheter and stylet through the skin and then proceed by placing the catheter into the vein.

Induction drugs Induction is best achieved through IV administration of a drug because this route allows for rapid airway control and enables careful titration to provide the desired effect without over dosing. The ideal induction agent would have a wide therapeutic index, rapid onset of action, quick metabolism or redistribution, no negative affect on other body systems (maintains respiratory drive), reversible, inexpensive, long shelf-life, and not be a controlled substance. This drug does not exist but a few come relatively close. Ketamine/midazolam This combination is a dissociative anesthetic (ketamine) coupled with a benzodiazepine (midazolam). Ketamine causes muscle rigidity whereas the benzodiazepine provides muscle relaxation. Pros This combination increases heart rate and blood pressure as a result of sympathetic nervous system stimulation. Ketamine antagonizes the NMDA receptor (an excitatory neurotransmitter in the brain) effectively blocking glutamate and stopping the amplification of pain signals. Induction is fast and drug is titrated to effect. Cons This combo can cause an increase in cardiac work and myocardial oxygen demand. In critical patients with depleted sympathetic reserve ketamine can drop cardiac output and blood pressure. The acidic pH of ketamine makes IM injections painful. This combination should be avoided in patients with a seizure history or history of head trauma, brain lesions, tumors and ocular disease and it can increase intracranial (ICP) and intraocular pressure (IOP). How to use A dose of ketamine is calculated based on the patient’s lean body weight. The volume of ketamine is matched by an equal volume of midazolam (or diazepam). Half of the calculated dose is given IV over 30-90 seconds then titrated to effect (until patient is able to be intubated). Notes Induction with ketamine/midazolam is slower than with propofol and patients will maintain more muscle and jaw tone. This is important to keep in mind to avoid over-dosing. Ketamine takes about 2 minutes to reach the brain and lasts about 20 minutes. Ketamine is a CIII controlled substance. Telazol This drug is a dissociative and sedative combination similar to ketamine/midazolam. The drugs in Telazol are tiletamine and zolazepam. This drug is reserved for induction of healthy dogs and cats as it cannot be tailored to meet the needs of the patient, it is not reversible and it has a relatively long duration of action. Telazol is a CIII controlled substance. Propofol A commonly used short-acting IV anesthetic with a relatively short shelf life. Pros Propofol is non-cumulative and it provides a rapid, smooth induction with a short duration of action. It can be used as a constant rate infusion (CRI) or total intravenous anesthesia (TIVA) in dogs or redosed via low-dose injections for procedures like a laceration repair, minor biopsies and endoscopy. It is good for head trauma as it doesn’t increase ICP and c-sections as it has minimal effects on . Cons Propofol can cause significant respiratory depression, apnea and cyanosis which is more pronounced when the drug is administered rapidly or in large doses. Animals given propofol must be monitored closely and supported (assist respirations to avoid hypoxemia). Propofol is highly protein bound so patients with hypoproteinemia will require lower doses. It is not currently a controlled substance. How to use Propofol should be calculated as a range giving the anesthetist the information necessary to dose appropriately. Depending on how sedate the patient is, a dose within the range is given as a slow IV push over about 20 seconds (low end for very sedate and mid-range for less sedate patients). The patient is assessed and the drug is titrated to effect, e.g. until intubation is easily achieved. Propofol takes about 90 seconds to reach the brain and then about 5 minutes to redistribute making it important to be ready but also be a bit patient. Alfaxalone Alfaxalone is a neuroactive steroid molecule, with central effects. Despite being an analogue of progesterone, Alfaxalone does not bind to sex hormone, glucocorticoid, or mineralocorticoid receptors Pros This drug provides a rapid induction and hypnosis with reasonable muscle relaxation and a decrease in cerebral oxygen demand. It is not irritating perivascularly, it has a wide safety margin, smooth induction and rapid but smooth recovery. It is non-cumulative and can be dosed daily. 881

Cons Dose-dependent respiratory depression and hypotension from myocardia depression and peripheral vasodilation that is offset by a reflex tachycardia. How to use A dose is calculated based on lean body weight and given IV over 60 seconds until the signs of anesthesia are appreciated, then it is titrated to effect. Rapid admin exacerbates side effects. Alfaxalone is a CIV controlled substance. Etomidate A short-acting injectable based in propylene glycol. Pros It is rapidly metabolized by the liver and plasma esterases (enzyme found in the plasma that cleave apart compounds and make them inactive) leading to a quick recovery. It produces minimal cardiovascular and respiratory depression and does not alter heart rate, cardiac contractility or blood pressure. This drug is a great choice for high-risk patients including those with pre-existing cardiac conditions and hepatic disease; it is not a controlled substance. Cons High cost, retching and myoclonus if patient is not adequately sedated or if it is underdosed, may cause pain on injection. Drug can inhibit steroid production for up to 4 hours. How to use Calculate dose based on lean body weight and administer the entire calculated dose as a slow IV push to well sedated patients. Opioid Opioids can be used to induce anesthesia is sick or debilitated patients. Pros Gentle and relatively safe induction as there is little negative effect on cardiovascular function. Cons Patients become very noise sensitive during this time so a quite induction area is essential. This method is really only useful in very ill or old patients that may not tolerate the cardiovascular effects of other induction agents. How to use A combination of an opioid and a benzodiazepine are given IV until patient is unconscious. Inhalants Inhalant anesthetics can also be used to induce anesthesia; however, mask or chamber inductions are stressful, airway control is slow and there is a great risk for contamination of the work environment. Over dosing of inhalant anesthetic during a mask or chamber induction is nearly always a given. Isoflurane and Sevoflurane are the two inhalants used with greatest frequency in veterinary medicine. Both have high vapor pressures requiring a precision vaporizer for delivery and low blood:gas solubility (the measure of the tendency of an inhalant to exist as a gas or dissolved in blood) making induction and recovery quick. The biggest differences between isoflurane and sevoflurane is their minimum alveolar concentration or MAC. MAC is the minimum concentration of drug in the lungs that is needed to keep 50% of patients immobile during surgical stimulation. It is used to discuss the relative ‘strength’ of the inhalant. Those with a lower MAC are more potent because less drug is needed to achieve the same effect. MAC is also used to help guide vaporizer settings. Pros Provides a relatively rapid induction and recovery with good muscle relaxation. The drug is eliminated primarily via the lung with little kidney and liver metabolism. Cons Dose-dependent central nervous system depression, dose dependent hypotension, myocardia depression and respiratory depression. Inhalants do not provide any analgesia and should never be used as the sole agent for painful procedures. There is also a risk of exposure to potentially harmful waste anesthetic gas. Inhalants are not safer than properly used injectable drugs. How to use MAC is used to guide the vaporizer setting for intubated animals and other drugs (adjuncts and premeds) are used to help keep the vaporizer setting as low as possible to avoid the negative dose-dependent side effects. A patient’s response to IV anesthetic induction will depend on the rate of administration (most anesthetics agents are titrated to effect) and over dosing is more likely when drugs are given too quickly and their side effects are not appreciated as they happen. Physiologic factors such as blood volume, total protein levels and blood pH play a role in the distribution of drugs throughout the body. The overall health status and organ function will affect how quickly the drug is distributed, metabolized and excreted which ultimately effects when and how long those effects last. Animals that are ill or debilitated in some way, including advanced age will require less induction drugs than their healthy counterparts. Premedications and the patient’s response to them will also influence the type and amount of agent needed. Using premedications will reduce the amount of induction drug need and thus further reduces unwanted side effects. As an added bonus, premedications make IV catheter placement easier and less stressful for the patient and the staff. 882

Endotracheal tubes and intubation There are three methods of selecting the proper sized endotracheal tube. One involves using the width of the nasal septum as a guide, another uses a chart with the animal’s lean body weight and recommended endotracheal tube (ETT) size and finally palpation of the outer diameter of the trachea in the region of the mid-neck. The most accurate way to choose a tube is lean body weight and breed. Choose three tubes, the size you expect to place plus one half size smaller and one half size larger. If intubating a brachycephalic breed, choose 2 sizes smaller since these breeds often have stenotic or narrow tracheas. Measure the length of the tube alongside the patient so that the tip of the tube lies midway between the larynx and thoracic inlet. ETT tubes that are too short may not pass through the larynx and those that are too long may pass into a bronchus resulting in ventilation of only one lung. If the tube extends more than 1 inch passed the incisors, it should be trimmed or a shorter tube should be used. Long tubes that stick out passed the incisors contribute to mechanical dead space that may lead to the rebreathing of carbon dioxide. Intubation should be performed using the largest sized tube possible to minimize the need to overinflate the ETT cuff. A laryngoscope should be used to allow visualization of the larynx and to get the user used to handling the equipment for when it is needed for a challenging or emergent intubation. Sterile lubricant should be lightly smeared on the ETT cuff to help facilitate intubation and to help form a seal within the trachea. Lidocaine is helpful in desensitizing the larynx in cats. Cuff inflation after placement should be done with care.

Complications of endotracheal intubation Esophageal intubation Inadvertent placement of the ETT into the esophagus. Clinical signs Absence of EtCO2 readings, patient will not maintain unconsciousness, inability to achieve a proper seal. Treatment Tube should be deflated, removed from esophagus and then placed into the trachea Bronchial intubation Intubation of one of the mainstem bronchi due to an excessively long ETT. Clinical signs Low pulse ox reading from one lung ventilation, difficulty keeping patient asleep Treatment Deflate cuff and gently pull ETT tube back so that the tip falls midway between the larynx and thoracic inlet. Use an ET tube of the same length to determine the length of the ET tube inside the patient. Laryngospasm Reflexive closure of the laryngeal cartilage usually from stimulation and inadequate anesthetic depth. Common in cats. Clinical signs Closed laryngeal cartilage and inability to place endotracheal tube. Treatment Desensitize laryngeal cartilage by placing a drop of lidocaine onto the area. Alternatively, deepen the plane of anesthesia to suppress the reflex. Do not continue to push the ET tube towards the laryngeal cartilage without first desensitizing it or deepening the level of aneshteisa as it will only make the spasms worse. Forceful intubation Endotracheal intubation should be gentle and easy. Although the largest sized tube should be placed, do not forcefully attempt to place a tube that is larger than necessary. Damage to delicate tissues at the back of the throat can lead to edema and potential airway obstruction. Clinical signs Red or swollen laryngeal tissues, difficulty breathings upon extubation, complete airway obstruction. Treatment If patient is having difficulty breathings post extubation it may be necessary to re-anesthetize them and place another endotracheal tube (smaller). Provide the patient with supplemental oxygen and try to keep them calm, be ready to intubate with a much smaller tube.

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Monitoring Without Monitors Kristen Cooley, BA, CVT, VTS (Anesthesia) University of Wisconsin Madison, WI

Anesthesia literally translates into “without sensation”. Our goal as anesthetists is to provide unconsciousness, amnesia, analgesia and muscle relaxation for a variety of procedures both invasive and non-invasive. Our ability to carefully string our patients out along the line between consciousness and unconsciousness compromises homeostasis making close monitoring essential.

Why monitor? Anesthetic emergencies are difficult to predict especially if the patient is not being monitored. Anesthetic emergencies can happen quickly and they can be devastating. It is better to be proactive rather than reactive when it comes to anesthetic complications. Our goal is to be able to walk that line with confidence by maximizing the safety of the anesthetic experience. There is no safe anesthesia, only safe anesthetists.

Morbidity and mortality (M&M) Morbidity refers to the prevalence of complications occurring secondary to hypoxia. Mortality is the rate of anesthetic related . Certain complications are more likely to increase morbidity and mortality:  Excessive bradycardia  Cardiac depression  Vasodilation  Hypotension  Arrhythmias  Hypoventilation  Hypoxemia  Hypothermia These obstacles all make it difficult for nutrient rich oxygen to reach the tissues. Diligent monitoring allows us to recognize and treat these potentially life threatening problems.

Monitoring basics According to the American College of Veterinary Anesthesia and Analgesia (ACVAA) guidelines on anesthesia, continuous awareness of the heart rate and rhythm along with the gross assessment of peripheral perfusion including pulse quality, mucous membrane color and capillary refill time are mandatory. Ventilation and oxygenation, anesthetic depth and body temperature are also important. If you didn’t have any monitors, you could still gather information using your eyes, ears and hands: Heart rate, pulse quality and vasomotor tone, respiratory rate and character, reflexes and tone, eye position and body temperature. Monitoring multiple parameters gives you a more complete picture of the physiologic status of the patient.

Heart rate Be aware of the normal heart rate range for the species you are working with as well as what is normal for the breed and the individual. Give yourself a range that is specific to this patient and stay away from extremes. Bradycardia is an excessively slow heart rate that affects cardiac output and leads to hypotension and poor perfusion. For most medium to large-breed dogs, the low 50’s with a normal blood pressure is often tolerated. Smaller dogs have higher resting heart rates as do cats so for this population the tolerated low for small dogs might be 80 bpm and for cat 120 bpm. When possible, also monitor blood pressure and end-tidal carbon dioxide for the most complete cardiovascular picture. Tachycardia is an excessively fast heart rate that affects cardiac output. The less time the heart spends in diastole, the less time it has to fill with blood so blood pressure is often affected by way of a decrease in stroke volume. Tachycardia also increases myocardial oxygen consumption and makes the heart have to work extra hard. Depending on the size of the patient and their normal resting heart rate, tachycardia in the dog is often in excess of 160-180 bpm and 240-280 bpm in the cat. Some causes of extremes of heart rate (and potential ways to remedy them) Bradycardia  Anesthetic overdose (lighten up)  Opioid administration (give an anticholenergic)  Alpha-2 agonist administration (reverse or no treatment)  Hypothermia (rewarm)  Hypoxia (oxygen therapy)

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 1st and 2nd degree A-V blockade (anticholenergics)  High vagal tone (anticholenergics) Tachycardia  Too light (deepen)  Painful (give analgesics)  Ketamine administration (no treatment)  Anticholenergics (decrease dose next time)  Inotropes (decrease infusion)  Hypovolemia (restore volume)  Hyperthermia (cool)  Hypoxemia (oxygen therapy)  Hypercarbia (ventilate or eliminate rebreathing of CO2)  Anesthesia recovery (comfort or no tx)

Pulse quality and vasomotor tone Palpation of a pulse is a subjective way of approximating blood pressure. It is done by evaluating the height and width of the pulse pressure waveform compared to normal. Bounding pulse- vasodilation as seen in sepsis and hypovolemia, where the vessel is easily collapsible. Weak and thready pulse- vasoconstriction as seen with alpha-2 administration, poor cardiac function, tachycardia, small stroke volumes. It is essential that the anesthetist palpate normal pulses in a variety of patients to make it easier to determine when a pulse is abnormal. Pulse quality is largely a reflection of stroke volume (the volume of blood pumped with each beat) and vessel size or vasomotor tone (the degree of vasodilation or vasoconstriction). Vasomotor tone regulates both peripheral and visceral perfusion. Vasodilation improves peripheral perfusion but can cause hypotension if too severe. Vasoconstriction can impair peripheral perfusion but also improves blood pressure. Assessing vasomotor tone can be done by evaluating mucous membrane color and capillary refill time. Normal mucous membrane color consists of a light to medium pink color and a capillary refill time of 1-2 seconds. Pale mucous membranes may indicate vasoconstriction (think about the pale gums of an animal given dexmedetomidine). Red mucous membranes may indicate vasodilation (think about a patient that is hyperthermic or too deeply anesthetized). Many things can cause vasodilation or vasoconstriction and the way to correct it is to address the cause.  Vasodilation o Systemic inflammation o Sepsis o Hypercapnia o Hyperthermia o Drugs (acepromazine, inhalants)  Vasoconstriction o Hypovolemia o Heart failure o Hypothermia o Drugs (alpha-2 agonists, sympathomimetics)

Pulse sites Pulses can be assessed from a variety of sites and each site offers a little different feel. It is essential for the anesthetist to become familiar each site. The femoral artery is located high up on the inner thigh where the leg meets the abdomen. This vessel is large and easy to palpate in most patients but can be challenging to find in obese or heavily muscled animals. The dorsal metatarsal artery is located on the dorsal aspect of the hind limb distal to the hock and over the metatarsals. This vessel is very accessible and great for arterial catheter placement. It can be difficult to palpate in vasoconstricted, hypotensive or small patients. The coccygeal artery is located on the proximal ventral tail is also used for arterial catheter placement. The radial artery is just proximal to the metacarpal pad on the forelimb and a bit medial. Because it is located distally on the limb, it too can be difficult to palpate in vasoconstricted, hypotensive or small animals. The lingual artery is on the ventral portion of the tongue near the lingual frenulum. It is only useful in anesthetized animals and is a great place to easily grab a pulse intra-operatively. In exotics, cats and small dogs, placing your hand around the chest is another way to feel the heartbeat.

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Respiratory rate and character All anesthetic drugs provide some degree of respiratory depression making respiratory monitoring and support vital. A change in breathing is a good indication of a change in patient status. Respiration is comprised of tidal volume (TV), respiratory rate (RR), and minute volume (MV).  TV (Vt) = the volume of air in a single breath (10-20 mL/kg)  RR (f) = the number of breaths per minute (8-15 br/min)  MV (V) = total volume of air breathed per minute (150-250L/kg/min)  TV X RR = MV Respiratory character describes the quality of the breaths being taken. Breaths can be shallow, deep, slow, fast, irregular or absent. Shallow breaths are often associated with a small tidal volume and they tend to be faster than normal breaths. The increase in rate makes up for the decrease in volume and normalizes the overall amount of air moved in one minute (minute ventilation). Deep breaths are characterized as having a large volume but slow rate. Apnea is the absence of spontaneous breathing and is common especially after induction of anesthesia. It is important that the anesthetist support the patient through this time by breathing for them until they can begin to breathe on their own. Bradypnea is a slow respiratory rate and without an end-tidal carbon dioxide monitor or blood gas analyzer, it is difficult to determine if these patients are adequately ventilating. Hypothermic patients and those that are a deep level of anesthesia will often exhibit this slow respiratory rate. Tachypnea is an increased respiratory rate with a number of possible causes: too light, too deep, hypoxia, hypercapnia, hyperthermia, hypotension, painful, septic, atelectasis etc. It may be helpful to give some larger breaths, check body temp, check BP, assess pain, assess anesthetic level etc to find the cause. Ventilation is defined as the act of breathing and respiration is the actual gas exchange. The adequacy of ventilation and appropriate gas exchange can really only be determined through arterial blood gas analysis or end-tidal carbon dioxide measurement.

Reflexes and tone The amount of muscle tone an animal has and whether or not their reflexes are present (and to what extent) gives the anesthetist an indication of the depth of anesthesia. The presence of reflexes indicates a lighter level of anesthesia but this is not always a bad thing. Brisk reflexes indicate that the patient is too light, but sluggish reflexes are ok as long as it doesn’t interfere with the procedure. The corneal reflex should always be present (unless paralyzed). Tone can be assessed simply as none, some or lots. Jaw tone, anal tone and general muscle tone should be taken into account when assessing the depth of anesthesia. No tone may indicate that the patient is a little deep or adequately anesthetized; some tone is ok and even good as long as it doesn’t interfere or cause harm but lots of tone is not good unless you are trying to recover the patient.

Eye position The eye is a little window into the central nervous system and its position can tell us a lot about how deeply our patients are anesthetized. If the eye is centrally facing the animal is either too deep or too light so it is important to also look at pupil size. A medium pupil indicates that the patient is light. A dilated pupil indicates a deep level of anesthesia and an immediate adjustment is necessary. A constricted pupil also indicates a deep level of anesthesia and an immediate adjustment is necessary. If they eye is in a ventral-medial position, the patient is at a good plane of anesthesia. Keep in mind that drugs can affect eye signs and pupil size making it important to assess the patient after pre-medication and before induction (opioids cause dilation; ketamine can affect the palpebral reflex etc).

Temperature Anesthesia depresses muscle activity, metabolism and thermoregulation and leads to hypothermia. A good temperature range is 98- 102 degrees Fahrenheit in dogs and cats perianesthesia. Hypothermia can contribute to an anesthetic overdose making necessary to decrease your doses in hypothermic patients! Animals less than 98 degrees Fahrenheit are considered hypothermic. Mild hypothermia is anywhere from 96-98 degrees Fahrenheit, moderate is 94-96, severe is 90-94 and anything less than 90 degrees is moribund due to CNS depression and imminent death if not corrected. Patients greater than 103.5 degrees Fahrenheit are considered hyperthermic (normal being 100.5-102.5). Cell damage occurs once the body temperature reaches 108 degrees.

YOU Your eyes, ears and hands can make excellent monitors if you know how to put them to work! Remember to be vigilant and look at the whole picture (co-existing disease, drugs given and currents meds, procedure, species, breed…). Seek knowledge, the more you know the more you know the more confident you will be. Remember to enjoy yourself, anesthesia is an art and a science and it can be fun.

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On PAR: Perils of Postanesthetic Recovery Kristen Cooley, BA, CVT, VTS (Anesthesia) University of Wisconsin Madison, WI

The recovery phase begins once the procedure ends and anesthesia ceases to be delivered. This may include turning off the inhalant or discontinuing total intravenous anesthesia (TIVA). Recovery ends when the patient is sternal, alert, extubated and normothermic. It is good practice to maintain the patient on 100% oxygen for 5 minutes after discontinuing inhalant. It is also common to disconnect the patient from the breathing system, occlude the patient end of the hoses and flush the system full of 100% oxygen then reconnect to the patient.  Patients continue to be respiratory depressed and can benefit from an enriched oxygen mixture  Waste anesthetic gas is corralled and disposed of decreasing exposure to personnel

Monitoring Patients should continue to be monitored during the recovery period and the extent to which they are monitored depends on their overall condition.  The ECG patches can be removed unless patient has a history of arrhythmias. Patients that have undergone major surgery like a splenectomy, GDV, pericardectomy, PDA ligation etc. should have the ECG maintained through recovery and likely post-operatively as well to check for arrhythmias. The most likely arrhythmias would be VPC’s but may progress to V-tach and negatively affect blood pressure.  The blood pressure cuff can be removed if the patient has been stable and normotensive. Patients that have been hypotensive or cases where blood pressure needs to be monitored closely (renal transplant) should continue with readings. Most patients’ blood pressure will increase once the inhalant is discontinued and they start to recover making it acceptable to discontinue this monitoring parameter. Blood pressure lines and ECG monitors can make it difficult to transfer patients to gurneys and recovery cages so these monitors are some of the first to be removed.  The pulse-oximeter should be maintained at least until the patient is extubated. This monitor is easy to place and maintain and is often hand-held making it simple to continue to use. Also, it will alert the anesthetist to hypoxemia- a condition that is likely after discontinuation of oxygen in the face of continued respiratory depression.  Continue to monitor EtCO2 until disconnected from oxygen or extubated. Continued respiratory depression is common during recovery and hypoventilation will be reflected in the EtCO2 readings giving the anesthetist the opportunity to assist respirations and help ward off hypoxemia.  Maintain supplemental heating if patient is normo- or hypothermic. Patients can lose heat during recovery because they are no longer under drapes and such. The temperature should be taken immediately post-op and then every 30 minutes until patient is able to maintain a normal temperature for two consecutive readings.  Some patients may become hyperthermic during recovery from anesthesia and these patients need to be monitored more closely and steps may need to be taken to reduce their temperature. Ways to this may include just removing supplemental heat, removing blankets, wetting down paws (alcohol is not recommended) or placing a wet towel in a cage with a patient. Acepromazine promotes vasodilation and may help bring the body temperature down. NSAIDS can help if the hyperthermia is actually pyrexia secondary to inflammation. Post-operative infections will not manifest immediately, it takes a day or so for the bacteria to gain a foothold so this should not be a consideration unless infection was present pre-operatively. Opioid induced hyperthermia is self-limiting and doesn’t typically require intervention.

Nursing care Good nursing care in recovery can have a dramatic positive effect on anesthesia recovery and post-operative comfort. Provide patients with a quiet and comfortable place to recover, keep them warm, express their bladder and offer food/water when awake. , hypoglycemia, hypothermia and a full bladder are all uncomfortable situations and can exacerbate pain and cause undue stress. Some patients will benefit from having cotton put into their ears to muffle outside noise and blanket over their cage to shield their eyes from the ambient light. Soft music (through a dog’s ear) and items from home (unwashed so they smell like home) are also comforting. When working with a post-op patient, be patient, go slow and narrate what you are doing to help calm the patient and to keep you calm as well. Pain management may include a constant rate infusion (CRI) or intermittent boluses of opioids, placement of a cold pack over the incision, massage of tense muscles or those strained during surgical positioning, and anxiolysis. Other steps that can be taken to increase comfort include cleaning off any left over scrub solution or blood from the surgical site. Blood and scrub can be itchy and their presence may prompt patients to bother the surgical site. Gently remove this with saline or water during recovery. 887

Patients that are hypothermic can be placed on a soft, insulated surface with a forced warm air heating blanket and a blanket over top that gets tucked under the patient or the pad creating a bubble of warm air. This bubble shouldn’t be disturbed unless necessary to check body temperature. If IV fluids are being given they can be warmed near the patient so heat is not lost between the source and the patient. Once the patient is able to maintain their body temp above 99 F, the supplemental heat can be removed. Once removed, the body temp should be checked in 30-60 minutes to make sure it is maintaining.

Recovery area and extubation Recovery should be smooth and stress-free and it should take place in a quiet area of the hospital where the lights can be dimmed as it is important to minimize unnecessary stimulation during recovery. Vitals signs such as HR, RR, CRT and MM color should be monitored every 5-10 minutes during recovery and body temperature every 30 minutes. SpO2, EtCO2 and BP/ECG can also be monitored and should be if the patient is recovering from a major procedure or is compromised in some way. A full recovery is defined as the point at which the patient is able to sit sternal with normal vital signs (HR, RR, body temp). Patients should be extubated when they are ready and showing signs which include alertness, swallowing and tongue tone. Patients do not have airway control until they are alert and able to swallow so these parameters are used to decide when it is safe to remove the endotracheal tube. Although massage and mild stimulation can be helpful is rousing patients, aggressive waking is contraindicated as it can lead to patient and staff injury. Recovering animals should be aloud to ‘sleep it off’ especially after a long or painful procedure. Some animals pop awake and start to chew on the tube, (these patients should be extubated quickly!) while others are content being able to breathe (brachycephalics). Do not deflate the endotracheal tube cuff until you are ready to extubate since vomitus or other fluid may be present in the pharynx and can be easily aspirated. Brachycephalic breeds will be alert, sternal and content with a tube in their mouths- these recoveries take a bit longer but these patients can be extubated when they are alert and sternal. Some patients will not be alert but will be swallowing slightly- these patients are not ready! Wait for alertness and tongue tone before pulling the tube unless instructed otherwise. Cats should be extubated as soon as possible as they are prone to laryngeal spasm upon extubation. After extubation patients should be watched closely every 15-20 minutes until a full recovery has been achieved- hypoventilation can quickly lead to hypoxemia when a respiratory depressed animal is breathing room air. The IV catheter should remain in place until full recovery and pain has been properly addressed. Catheters kept in over night should be wrapped and kept clean.

Post-operative pain management Pain should be assessed as soon as the patient is conscious. Review the anesthesia record to gather information on which analgesics have been given and when. Additional analgesics should be given during recovery if the patient is due for them or if they are showing signs of pain. Pain can be assessed using any number of different pain scoring sheets including: University of Melbourne Pain Scale, Glasgow Composite Measure Pain Score or the Colorado State University Acute Pain Scale (author recommendation). Pain should be evaluated every hour for the first 4-6 hours following surgery and then regularly until discharge. High quality pain management should be instituted for at least the first 24 hours post-op and may continue if necessary. High quality means opioids plus NSAIDS (if tolerated) plus or minus sedation or adjunctive medications along with good nursing care.

To go home medications for pain management TGH meds: 3-7 days of analgesia depending on the type of procedure. PO drugs like tramadol, NSAIDS, gabapentin and amantadine are common. Certain opioids like fentanyl patches or buprenorphine can also be sent home because they are given either OTM or transdermal but the risk of abuse by humans is high. Tramadol Weak mu receptor agonist. Can be used in dogs and cats but has a very bitter and is often refused by many felines. Decent for acute and chronic pain management and it may have increased benefit if given chronically because it inhibits the reuptake of norepinephrine and serotonin. It should not be used in conjunction with other drugs of this nature or TCA’s or MAOI’s. Tramadol may increase the seizure threshold so use caution in animals with a seizure history. Gabapentin Antiepileptic at high doses and anti-hyperalgesic at moderate doses. Works well for the treatment of neuropathic pain. Drug should be stepped down when discontinued to avoid rebound pain. Liquid form may contain xylitol so it is not recommended for use in dogs and cats. It is not an analgesic in and of itself so it should be used with other drugs like NSAIDS or tramadol. Excreted unchanged in the urine so care should be taken when dosing renal patients. Amantadine NMDA antagonist and is a great analgesic adjunct for acute and chronic pain in dogs and cats. It blocks wind up or central sensitization in the dorsal horn of the spinal cord. It is used as an antiviral drug in humans and can be used in combination with NSAIDS or tramadol. Available in capsule and liquid. Excreted unchanged in urine so use caution in renal patients.

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Fentanyl patch Class II controlled substances. Transdermal patch will provide systemic absorption and provide 3-4 days of analgesia. If removed prior to 3 days it will continue to provide analgesia for 6-12 hours after patch removal. Patch is very popular because it is easy to use but the absorption rate in dogs and cats can be highly variable. It may work really well for some patients and not at all in others. It takes about 6-12 hours in cats and 12-24 hours in dogs to reach blood levels so opioids should be supplemented until the patch kicks in. 12.5 mcg/hr; 25 mcg/hr; 50 mcg/hr; 100 mcg/hr. patch size is selected based on patient weight. The patch can be placed anywhere on the body where there is intact hairless skin. Transdermal fentanyl or recucyra Recently approved for use in the US. It is a transdermal fentanyl solution (50 mg/ml) that is applied to the skin between the shoulder blades 2-4 hours pre-operatively and will provide up to 4 days of analgesia. It is not meant to replace the use of other opioids during surgery but may prove to be enough analgesia when used in conjunction with other CRI’s like lidocaine, locals or NSAIDS to provide multimodal analgesia. Proper training is necessary prior to use and extreme care must be taken to prevent direct contact with the site of application for at least 3 days. OTM buprenorphine A common post-op drug used in cats. Buprenorphine is a partial mu agonist and a class II controlled substance. Transmucosal administration in the cat has almost 100% bioavailability. OTM means allowing the drug to be aborbed across the mucous membranes, not given orally. Oral administration is not efficacious due to the first pass effect. The bioavailability of OTM buprenorphine in dogs is around 30% so this route is not recommended in dogs. SR buprenorphine A compounded medication that is not FDA approved. The drug is set in a lipid carrier which allows it to absorb over a period of time. It is given SQ and may sting on administration but can provide up to 72 hours of analgesia. This drug is used more frequently in cats than dogs likely because they seem to tolerate it better. High doses can cause euphoria (purring, rolling, rubbing). This drug is very difficult to reverse and may require hospitalization for supportive care and a naloxone CRI in extreme cases. Simbadol A high potency buprenorphine for SQ use in cats. It provides 24 hours of analgesia and is well tolerated by most felines. Side effects are similar to SR buprenorphine but Simbadol is FDA approved and well regulated.

Rough recoveries The majority of patients who have been given a balance of anesthetic drugs will have a smooth recovery. However, some will wake up dysphoric or painful despite our best efforts. The quality of the induction, the temperament of the patient, previous rough anesthetic recoveries and the length of the procedure can all affect the recovery. Evaluate analgesic history and effectiveness throughout the procedure and especially prior to recovery. If the duration of action of a sedative/analgesic has lapsed, consider re-dosing prior to recovery or at least be ready with analgesics. Rough recoveries can be due to pain, dysphoria or emergence delirium and it is often difficult to determine which is which.  Dysphoria: characterized by agitation, excitement, restlessness, excessive vocalization and disorientation. Patient is not responsive to human voice and will not look/focus on you. Cats tend to act as though they are hallucinating, they may open- mouth breathe, vocalize and pace. Dysphoria is often precipitated by opioids and patients that are dysphoric from opioids will not benefit from additional opioids. They may however, benefit from a low dose of butorphanol or naloxone to reverse the side effects of opioids. This may then lead to a painful patient because reversal removes or lessens analgesia in an attempt to calm the patient so adjunctive analgesics may be necessary to keep them comfortable.  Emergence delirium: dissociated state of consciousness in which the patient is unaware of their surroundings. Patient may be excited, agitated, restless and they may vocalize. This most often occurs in patients who have no sedative drugs on board or when recovering from a dissociative anesthetic (ketamine, telazol). Other situations explained in the human literature that may preclude emergence delirium include hypoglycemia, hypoxia, severe hypercapnia, hypotension and distended bladder.  There are a few ways to handle this situation; o Restrain the patient until they have exited this post-anesthesia excitement phase. This is not always possible or safe. o Reanesthetize the patient using induction drugs, reintubate or supplement oxygen and allow the patient to wake back up (this is called a do-over) o Reanesthetize and also give a sedative like dexmedetomidine or acepromazine o Just give a sedative and hope it works before someone gets hurt!  Pain: When dealing with rough recoveries it is important to address potential pain as well as anxiety since our patients cannot verbalize when they hurt. Painful patients are responsive to human voice and will relax and stop vocalizing once analgeiscs take effect. Dexmedetomidine is an excellent choice in patients that can handle the drug because it offers both analgesia and sedation and is fully reversible. It is possible to achieve the desired effect with very small doses given IV (1-2 mcg/kg).

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 Slow recoveries: Some patients seem to take forever to wake up. Hypothermia can slow down drug metabolism and lead to a prolonged recovery. Keep patients warm as they recover and help circulation by gently massaging and moving the limbs. Post-operative opioids can also re-sedate a patient after surgery. These drugs are given to control pain so it is not recommended that they be reversed unless necessary. If necessary, reversal can be achieved with butorphanol or low dose and titrated naloxone to reverse the side effects but preserve most of the analgesia.  Rapid recoveries: Rapid recoveries can be dangerous if the patient is dysphoric or delirious. Many rapid recoveries are due to patients waking up on inhalant alone- no real analgesia and very little premedications still on board. These recoveries can not always be predicted but by staying ahead of pain management and conscious of when premeds wear off, many rapid and rough recoveries can be avoided.

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The Cool Observer: Monitoring Anesthesia with Confidence Kristen Cooley, BA, CVT, VTS (Anesthesia) University of Wisconsin Madison, WI

Our goal as anesthetists is to provide our patients with an expert balance between the effects of anesthetic drugs, both wanted and unwanted, the affects of underlying illness and the intensity of procedural stimulation. To achieve this, we must depress the central nervous system sufficiently to keep our patients unaware and relaxed, immobile and pain-free while at the same time maintaining near normal cardiopulmonary function. This compromise to homeostasis brings with it the potential for problems. However, the source for most anesthetic complications is human error (70%) and those errors are often associated with poor patient monitoring. Constant vigilance of the anesthetized patient allows us to be proactive rather than reactive through anesthetic depth adjustment and need-based patient support. As anesthetic drugs have become more refined and physiologic monitors more sophisticated, successful anesthesia is no longer defined as the lack of mortality- just surviving anesthesia isn’t enough- but by the lack of morbidity. Our ultimate goal is to bring patients through the anesthesia experience without any ill effects. The American College of Veterinary Anesthesia and Analgesia or ACVAA published a position statement in 2009 regarding recommendations for monitoring anesthetized veterinary patients. The ACVAA recommends frequent and continuous monitoring of circulation, oxygenation, ventilation and body temperature by trained personnel. Appropriate physiologic support through the utilization of hands-on monitoring in conjunction with physiologic monitors can improve the practice of veterinary anesthesia. However, anesthetic monitors are only as good as the person using them- it takes a well-trained technician or nurse to be able to recognize abnormalities and know how to properly respond.

Circulation Adequate blood pressure is necessary to deliver oxygen and nutrients to all tissues in the body. The components of blood pressure include systolic (peak pressure during contraction; stroke volume and arterial compliance), diastolic (minimum pressure during relaxation of the heart; systemic vascular resistance and heart rate) and mean arterial pressure (driving pressure for organ perfusion). Normal values: Systolic 100-140 mm Hg, Diastolic 50-100 mm Hg, Mean 70-120 mm Hg Arterial blood pressure is comprised of cardiac output (the volume of blood ejected over one minute) and systemic vascular resistance (the resistance offered by the peripheral vessels). Stroke volume (the volume of blood pumped with each beat) and heart rate make up cardiac output. Preload (the volume of blood returned to the heart), cardiac contractility (the intrinsic strength of the heart’s contraction) and afterload (the tension against which the ventricle must contract) all contribute to stroke volume. Afterload is also a factor in systemic vascular resistance as is vessel diameter. Autoregulation is the body’s ability to maintain normal perfusion to vital organs despite changed in systemic arterial pressure. Autoregulation can maintain normal renal blood flow when systemic blood flow falls outside of 60-160 mm Hg range. There are two ways to measure blood pressure, indirectly using non-invasive methods and directly using invasive methods. Non- invasive methods include the use of oscillometric blood pressure monitors and a Doppler; both utilize a pneumatic cuff placed over a peripheral artery. The width of the blood pressure cuff bladder should be 40% of the circumference of the limb to obtain an accurate reading. Cuffs that are too large may lead to underestimated pressures and cuffs that are too small may lead to overestimated pressures. It is better to choose a wider cuff over a smaller one if the ideal size is not available as the margin of error is less. The monitor should be set to read every 3-5 minutes for anesthetized patients. Blood pressures read more frequently do not given the limb a chance to recover and re-perfuse with blood; pressures read less frequently may lead to missed events. The Doppler can be a more accurate way of monitoring blood pressure in small patients but is prone to user error. Cuff selection and placement, maximum inflation pressure, and deflation rate are determined by the operator and can vary greatly. In dogs, the pressure at which the sound of blood flow returns after cuff inflation reflects the systolic blood pressure. In cats the pressure more closely reflects the mean arterial pressure. Invasive blood pressure (IBP) measurement is the gold standard of blood pressure monitoring. This method requires the aseptic insertion of a catheter into an artery (dorsal pedal, coccygeal, femoral, lingual, facial, auricular). Most monitors capable of measuring invasive pressures will display a continuous systolic, diastolic and mean arterial blood pressure reading as well as a waveform. By observing the velocity or upswing of the arterial pressure wave (anacrotic ascending limb) one can glean information about changes in cardiac contractility. This method of blood pressure assessment is essential in a number of clinical settings including major surgery, trauma and critical care. Since oscillometric monitors estimate blood pressure and are great trend monitors, isolated abnormal readings may not be a cause for alarm. If the blood pressure is trending, evaluate the patient by assessing anesthetic depth and vital signs. Adjustments should be made based on findings (deepen anesthesia, assist respirations, provide more analgesia etc). If the blood pressure is trending down the

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same algorithm is used but the corrective steps will differ. If sudden and significant changes in blood pressure occur, evaluate the patient and communicate with the clinician then recheck the pressure and make adjustments based on findings. Hypotension is defined as a systolic blood pressure less than 80 mmHg and a MAP of less than 60 mmHg in small animals. The reduction may be significant enough to cause serious complications including shock and death. Consequences of hypotension may include hypoxemia, reduced drug metabolism, worsening of V/Q mismatch (see Reasons for Hypoxemia), delayed anesthetic recovery, renal failure, central nervous system (CNS) abnormalities (blindness, neurologic deficits), shock, cardiac arrest and death.  Drug side effects/excessive anesthetic depth: Inhalants, acepromazine, anaphylaxis or histamine release (rapid IV morphine), radiographinc contrast media, beta blockers, rapid IV antibiotics etc.  Decreased venous return to the heart: Hemorrhage, fluid loss, compression of vena cava, increased intra-abdominal pressure, mechanical or manual ventilation  Cardiac disease: Arrhythmias, valvular disease, cardiomyopathy, congestive heart disease, pericardial effusion  Mechanical: Closed pop-off valve, overinflated re-breathing bag (decreases venous return)  Shock/vasoactive substance release as seen with manipulation of damaged or diseased organs Hypertension is less common in veterinary anesthesia but no less important. Hypertension can cause greater swings in blood pressure and end-organ damage and may be the result of:  Mechanical error  Sympathetic stimulation: Hypercarbia (indirect SNS stimulation), pain, light level of anesthesia  Anesthetic drugs: Alpha-2 agonists, ketamine, inotropes, pressors  Disease states: Pheochromocytoma, chronic renal disease, hyperthyroidism, increased intracranial pressure, heart disease, etc. Treatment options for hypo- and hypertension depend on the underlying cause and may include an assessment and adjustment of anesthetic depth, assessment of analgesic efficacy, expansion of intravascular volume (hypotension) and possibly drug therapy. The ECG peripherally detects the electrical signals generated by the heart. This monitor reveals information about the heart’s electrical activity but not it’s mechanical function. The ECG is essential in diagnosing arrhythmias and should be used during the pre- operative evaluation of high-risk or trauma patients, intra-operatively for all procedures, and post-operative for those cases requiring follow up information on the electrical stability of the heart.

Conduction The P wave, the first small and usually positive wave signifies atrial depolarization initiated by the SA node. There is a brief pause between the P wave and the QRS complex which corresponds to the time it takes for the impulse to travel from the SA node through the AV node and bundle of His. This pause is called the P-R interval and it also represents the time between atrial depolarization and ventricular depolarization. The QRS complex represents ventricular depolarization. This complex starts out with a negative deflection (Q) and then takes a sharp and significant upswing (R) and then comes back down sometimes dipping just below baseline (S). Depolarization should happen quickly producing a narrow QRS complex. A short pause is seen after this QRS complex followed by the T wave, this is called the ST segment. The T wave represents ventricular repolarization. The time between the R wave of one complex and the R wave of the following complex is termed the R-R interval. This interval helps us determine heart rate and regularity. A normal sinus rhythm follows the conduction pattern from its origination in the SA node, through the AV node, Bundle of His, bundle branches and Purkinje fibers. Since the SA node has the fastest impulse rate it typically overrides the other pacemaker cells in the heart. In the anesthetized patient, the ECG is used as a means of detecting dysrhythmias and not necessarily for diagnosing arrhythmias. ECG’s are a great way to monitor heart rate and rhythm but the ECG can appear normal when myocardial performance and blood pressure are poor. Common arrhythmias  1st degree AV block: prolongation of the PR interval  2nd degree AV block: dropped QRS complexes o Type 1: variable PR interval (av node fatigue) o Type 2: constant PR interval before and after dropped beat (more serious- can progress)  3rd degree AV block: complete dissociation between SA and AV node  VPC’s: Impulse originating distal to SA node which can effect hemodynamics  V-tach: rapid ventricular rate, unstable rhythm  V-fib: Irregular tachyarrhythmia, unstable, arrest

Oxygenation Oxygenation is the process of taking oxygen molecules from inspired air and delivering them to tissues to sustain aerobic cellular metabolism. PaO2 is the measure of oxygen dissolved in plasma and it is determined by arterial blood gas measurement. This value 892

tells us the efficiency of the lungs to deliver oxygen to the blood and is measured in mmHg (millimeters of mercury). Normal PaO2 values depend on inspired O2 concentration. To determine the normal PaO2 values, multiply inspired oxygen concentration by 4-5. For example, room air is ~ 21% O2 so the normal PaO2 value for an animal breathing room air is 80-110 mm Hg. A patient breathing 100% oxygen should then have a PaO2 value of 400-500 mm Hg. SpO2 is peripheral oxygen saturation of hemoglobin that is measured as a percent and estimates PaO2. The numbers of concern for each value are not equal because they are based on the normal oxyhemoglobin dissociation curve. This curve illustrates the relationship between PaO2 and SpO2.The pulse ox utilizes wavelengths of light; deoxygenated blood absorbs red light whereas oxygenated blood absorbs infrared light. The ratio of red to infrared light provides us with an SpO2 value. An SpO2 of 95% and above represents adequate oxygenation and a precipitous drop in PaO2 can be seen at an SpO2 of 94% and below indicating early hypoxemia. When the SpO2 falls to 90% the PaO2 is as low as 60 mm Hg which is defined as severe hypoxemia and warrants treatment. There are five reasons for hypoxemia: Low inspired oxygen concentrations is usually not an issue when using 100% O2, but it is important to check the oxygen supply and make sure the flowmeter is on and in good working order. If using N2O, check ratios or discontinue mixture. A sedated or anesthetized animal breathing room air is often at risk for hypoxemia making supplemental oxygen Hypoventilation is common under anesthesia in spontaneously breathing patients because most anesthetics are respiratory depressants. An animal that appears to be breathing adequately may not be. The adequacy of ventilation can only be determined by an arterial blood gas or estimated using end-tidal CO2 monitoring. Patients at risk for hypoventilation (obese, geriatric, dorsal recumbancy, deep anesthesia) should be manually or mechanically ventilated. V/Q mismatch stands for ventilation (V) and perfusion (Q) mismatch. It is characterized by inflated alveoli that are not perfused (ventilation is good but blood flow is bad) or perfused alveoli that are not well inflated (blood flow is good but ventilation is bad). Some common causes of V/Q mismatch include anesthesia, inadequate ventilation, atelectasis, hypotension, positioning. Diffusion impairment is an increase in the distance that oxygen has to travel to get from the alveoli to the capillary and vice- versa. Pulmonary edema, pulmonary fibrosis and pneumonia can all cause diffusion impairment. Shunting is defined as venous blood by-passing oxygenation in the lungs and mixing with arterial blood decreasing PaO2. Collapsed lung lobes, PDA and VSD can all lead to shunting and hypoxemia. Many pulse-oximeters are prone to malfunction, bias and variation especially if they have been designed to be used on humans instead of animals. Some potential reasons for flawed readings include the fact that tissue, venous/capillary blood, and skin pigment all absorb infrared light and motion, location of the probe, wetness/dryness, tissue thickness, electrical/optical interference can effect readings. When inaccurate, the pulse-ox is usually inaccurately low. Check patient status first, then troubleshoot monitor because a poorly functioning monitor may indicate poor systemic perfusion. All monitors have limitation and the pulse-ox is no exception. This monitor does not assess the adequacy of ventilation; it only estimates the amount of oxygen saturating the present hemoglobin. It also gives a pulse rate and in monitors with plethsysmography (a graphic waveform of blood flow beneath the probe) you can glean some information concerning pulse pressure and volume status. Also, it can be misleading in anemic patients who may have an SpO2 reading of 100% (available hemoglobin is saturated) when in fact their tissues are hypoxic. This monitor can give the anesthetist a false sense of security because animals on 100% oxygen won’t indicate impending hypoxemia until the PaO2 falls to 80 mm Hg (all the way from 400!).

Ventilation The capnometer gives us end-tidal carbon dioxide (EtCO2) value which estimates PaCO2. PaCO2 is the amount of CO2 dissolved in arterial blood and it gives us information about how well an animal is ventilating. Carbon dioxide is important in two ways, it defines the respiratory cycle and it is a by-product of cellular metabolism (cells produce it, lungs excrete it). As an anesthetic monitor, the capnometer non-invasively gauges the adequacy of ventilation and it helps guide assisted breaths and . This monitor increases our ability to detect potential problems by alerting us to leaks within the breathing system, apnea and fluctuations in respiration on a breath-by-breath basis, deviations in chest compliance and changes in cardiac output (including the effectiveness of chest compressions during CPR). It can also help us determine if a patient is properly intubated and alerts us when a patient is inadvertently extubated. Normal PaO2 is 35-45 mm Hg and the end-tidal CO2 level is typically 3-5 mm Hg greater than the actual PaO2. For this reason, the appropriate normal range for EtCO2 is 30-45 mm Hg. Abnormal EtCO2 readings may have a respiratory or a metabolic cause.  Elevated EtCO2 (> 45 mm Hg) o Hypoventilation, excessive depth, inappropriate ventilator settings, exhausted soda lime, machine malfunction, hyperthermia, airway obstruction, abdominal or thoracic restrictive disease, pleural space filling  Low EtCO2 (< 30 mm Hg) o Hyperventilation, light level of anesthesia, hypoxemia, pain, hypothermia, inappropriate ventilator settings, decreased cardiac output

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Normal levels of inspired CO2 range from 0-3 mm Hg and any value greater than 3 mm Hg may indicate a problem. Common causes of elevated inspired CO2 levels include a leak in the breathing system or machine, excessive dead space, exhausted soda lime or inadequate fresh gas flows in a non-rebreathing system

Temperature Temperature can be monitored intermittently via rectal thermometer or continuously via rectal/esophageal probe connected to a mechanical monitor. Properly placing a reusable probe down the esophagus provides an easy and accurate core body temperature reading. Minimizing patient heat loss can be achieved by controlling conductive, convective, radiant and evaporative heat loss and by providing supplemental heat support. Insulating a patient from the cool environment with the use of blankets and towels and minimizing prep times can help maintain normal body temperature. Convective warming devices can also be employed and are an efficient way to maintain and improve body temperature under anesthesia. Rice socks, electric heating blankets and warm water bags/bottles/gloves should be avoided because they have the tendency to cause burns (Haskins, 1999). If they must be used, do not allow the heat source to contact the patient directly and remove once they cool to patient temperature as they will begin to absorb heat from the patient at that time.

Consequences of hypothermia  The release of catecholamines in response to the stress of a decreased body temperature o Subsequent vasoconstriction, tachycardia and hypertension increase post-operative morbidity  Coagulation deficiencies o Hypothermia impairs platelet function, decreases coagulation pathways and increases fibrolysis  Decreased wound healing o Thermoregulatory vasoconstriction reduces wound oxygen tension, impairs oxidative killing by neutrophils and reduces collagen deposition o Hypothermia directly impairs immune function and increases post-operative wound infections (Sessler, 2006)  Reduction in necessary amount of inhalant o Hypothermia increases solubility and decreases clearance leading to the significant potential for anesthetic overdose  Hypothermia leads to post-operative shivering o Shivering greatly increases metabolic oxygen consumption and when coupled with residual respiratory depression and atelectesis, hypoxemia is likely. The intelligent use of mechanical monitors will aid the clinician in supporting patients during times of compromised homeostasis as seen under anesthesia. Respecting the guidelines put forth by the ACVA to continuously monitor circulation, oxygenation, ventilation and body temperature will improve the practice of anesthesia and reduce patient morbidity by providing positive anesthetic outcomes.

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The Ins and Outs of the Anesthesia Machine Kristen Cooley, BA, CVT, VTS (Anesthesia) University of Wisconsin Madison, WI

The anesthesia machine The components of the anesthesia machine work together to deliver controlled amounts of oxygen and anesthetic gas to a breathing system. Anesthesia machines are designed to deliver volatile anesthetics in the presence of oxygen. One hundred percent oxygen is commonly used to deliver anesthetics for the delivery of adequate amounts of O2 to tissues. Oxygen delivery is reduced because anesthetics reduce tidal volume and cause some degree of respiratory depression.

Oxygen cylinders Oxygen is often obtained as compressed gas in a pressurized cylinder. Pressurization is necessary to fit a large amount into a relatively small container. Various sized tanks are available and each size is designated with a letter A-H but the most commonly used sizes are E cylinders and H tanks. When the cylinders are full they contain 2200 psi of gas with varying volumes based on size: E-cylinders  Small and easy to carry  Holds ~770 L of oxygen  Commonly found attached to an anesthetic machine H-cylinders  Huge and heavy  Holds ~7000 L of oxygen  Commonly found in a closet or chained to a wall Other medical gases can be obtained in compressed cylinders as well. To keep all medical gases organized they are each assigned a cylinder color.  Oxygen is green in the US, white in Canada and Europe  Nitrous oxide is blue  Air is yellow in the US, grey, white and black in Canada and Europe  Nitrogen is black All knobs, hoses and connectors associated with these gases should also be of the designated color.

Pressure gauge and regulator Located on the cylinder yoke, this apparatus provides a safe, constant operating pressure within the machine regardless of the pressure in the tank. It also has a gauge connected to it that displays the tank pressure. The volume of gases that are not liquid at room temperature can be determined based on the tank pressure. The volume of gas is proportional to the pressure in the tank. For example, if a full tank is 2200 psi and contains 600 liters of gas then a half full tank will have a pressure of 1100 psi when it contains 300 liters of gas.

Flowmeter The flowmeter is made up of a graduated glass tube and some sort of float (ball or plumb bob). It is typically expressed in L/min or mL/min. Oxygen enters the bottom of the flowmeter and exits the top. It allows the anesthetist to adjust the O2 flow rate. The flow of oxygen can be increased to speed the change of inhalant concentration in the machine.

Time constants (TC) A time constant represents the volume of the machine in relation to the flow of gases. It takes approximately 3 time constants to see a 95% change in the concentration within the system when a change is made to the vaporizer. A typical small animal anesthesia machine volume (components of breathing system) will have around a 5 L volume and is dependent on the size of the absorbent canister, breathing bag size and diameter and length of the breathing hoses. Math  3 TC X 5 L / 1L/min = 15 min With a flowrate of 1 L/min it takes 15 min to approach a steady state  3 TC X 5L / 2L/min = 7.5 min With a flowrate of 2 L/min it takes 7.5 min to approach a steady state Factors affecting changes in anesthetic concentration include hypoventilation and apnea. By assisting ventilation you facilitate gas exchange, this includes oxygen as well as anesthetic CAUTION! Increases in flowrates should always be monitored closely because an increase in system flow also means an increase in flow to patient. Gases are dry and cool and can be very drying to respiratory tract and will cool patients very quickly. Never close

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the pop-off valve when you have higher flows because pressure builds much quicker so you have less time to react! High flows waste anesthetic gas and oxygen and money!

Vaporizers Vaporizers are responsible for converting liquid anesthetic to a gas. It adds controlled amounts of anesthetic gas to O2 and it can only release anesthetic in the presence of oxygen (or N2O). Each vaporizer is calibrated for a specific agent based on that agent’s vapor pressure. It is essential to never fill a vaporizer with an anesthetic other than the one it is intended for.

Oxygen flush valve This button allows fresh oxygen to by-pass vaporizer and enter breathing circuit directly at 30-50 L/min. It is a handy but dangerous component because over pressurization is easy.

Flush valve CAUTION  Use with extreme care or not at all when the circuit is connected to a patient  NEVER use with a non-rebreathing system  NEVER use when pop-off is closed  DO NOT use in small patients  The use of this valve decreases anesthetic concentration in the system

Fresh gas outlet and common gas inlet The gas mixture (O2 and anesthetic) exits the vaporizer and machine at the fresh gas outlet. The mixture follows a flexible tube and enters the breathing system at the fresh gas inlet. This port is necessary to hook up a non-rebreathing circuit

Flutter valves Fresh gas enters the one-way inspiratory valve on its way to the patient and then is exhaled through the one-way expiratory valve. These valves are only utilized with a circle system to allow for re-breathing of gases.

Pop-off valve/APL The pop-off or adjustable pressure limiting valve prevents build-up of pressure or volume within the circuit. Most will vent pressure at 2 cm of water. Allowing pressure to build-up may impede venous return or cause barotrauma. It is good practice to always keep a hand on the pop-off valve (when you close it) to make sure that it gets re-opened. There are pop-off occlusion valves are available (SurgiVet.com).

Carbon dioxide absorber The carbon dioxide absorber contains absorbent granules that remove CO2 from expired gas. Any gas that gets returned to the patient passes through the carbon dioxide absorber on its way back. Utilization of the carbon dioxide absorber lowers fresh gas flows, reduces waste of anesthetic and oxygen, lowers the overall cost of anesthesia by allowing for the re-breathing of gases. Carbon dioxide absorbent is made up of granules of calcium hydroxide or barium hydroxide. When they come into contact with CO2 an exothermic reaction takes place that produces both heat and water. The granules must be changed when exhausted. Many formulations have a pH color indicator to alert when to change it. Granules start off white and may change to lavender or blue when they have had their fill of carbon dioxide. This is a short-lived chemical reaction allowing spent granules to revert back to white once they are no longer being bombarded with CO2. There are formulations available that elicit a permanent color change. If the status of the granules is in question, handle them; fresh granules can be easily chipped and crumbled whereas spent granules are very hard and brittle.

Manometer The manometer measures the pressure of gases within the anesthetic circuit and patient. This gauge is very useful when breathing for a patient or setting up a ventilator and should be referenced with each manual breath.

Scavenging system The scavenging system collects waste gas and disposes of it. Two types of scavenging systems exist, passive disposal made up of non- circulating ventilation systems or activated charcoal and active systems consisting of a central vacuum.

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Components of breathing system The breathing system is comprised of everything after the common gas outlet that breath passes through. This includes the breathing hoses, breathing bag, CO2 absorber, and scavenge system. The breathing system functions to deliver oxygen and anesthetic gas to the patient, to remove CO2 from exhalation and to facilitate manual ventilation.

Anesthetic systems/circuits The two types of anesthetic circuits available include circle or rebreathing systems and the non-rebreathing circuit. The circle system is commonly reserved for patients greater than 7 kg and it utilizes the inspiratory and expiratory valves as well as the CO2 absorber. The non-rebreathing system is most often used for patients less than 7 kg and bypasses the bulk of the anesthesia machine utilizing only the flowmeter and vaporizer. Circle systems ‘Y’ hoses: Two legs connected by a “Y” at the patient end  Universal F: One coaxial tube that connects to inspiratory/expiratory valves using a small hose Non-rebreathing systems  No exhaled gas is returned to patient o Adequate oxygen flows required to prevent rebreathing of gases o 250-500 ml/kg/min  Evacuated by scavenge based on O2 flows  No CO2 absorber  Many types, two common are both modified Mapleson D o Ayers T o Bain

Circle system vs. Non-rebreathing system  Circle system o Low flows o Rebreating of gases o More economical o Recycled air is warmer and humidified than fresh gas o May be cumbersome o More resistance to breathing for small patients  Non-rebreathing system o Little resistance to breathing o Does not require a CO2 absorber o Allows inspired concentrations of anesthetic to be changed rapidly o Promotes hypothermia and drying of respiratory tract o Can be wasteful if used in larger patients (high flows)

Breathing bags Breathing bags (also called rebreating bags or reservoir bags) should hold a minimum of 60 ml/kg of the patient’s body weight. This can also be figured out by multiplying 5-6 X tidal volume (10-15 mL/kg). When choosing a bag size it is important to always round up. An appropriately sized bag allows patient to take a large breath, it allows the anesthetist to observe breathing and to breathe for the patient. The size of the bag does matter, if the bag is too big it impairs monitoring of breathing rate, adds volume to machine and slows changes in inspiratory anesthetic concentrations when settings are altered. If the bag is too small the animal is unable to take an adequate breath because the bag collapses on inspiration.

Endotracheal tubes Many endotracheal tubes are intended for one time use only. The biggest drawback of reusing them is that the cuffs tend to wear out over time. All ET tubes should be checked for leaks prior to each use. To do this, make sure the cuff inflates and stays inflated. You can also place an inflated tube in a bowl of water and look for leaks/bubbles. All leaky tubes should be discarded.

Mechanical dead space Mechanical dead space is the area where bi-directional flow takes place. This includes the endotracheal tube and anything between the Y-piece and the ET tube such as the CO2 monitor adapter, swivel adapter, elbow etc. Excessive pieces should be kept to a minimum in small patients. It is important to note that hose length does not contribute to dead space but can increase the resistance to breathing.

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Bottle Babies: Tips for Helping Foster Kittens Amanda Dykstra, DVM University of Tennessee Knoxville, TN

As shelter intakes show a decreasing trend and live release rates tend to be increasing across much of the country, one population that is still at risk for euthanasia is pre-weaned kittens. It is common for shelters to take in multiple litters of kittens in a single day, often brought to the facility by Good Samaritans. Rarely do people realize that many of those kittens will be euthanized due to a lack of resources available to care for them and a lack of homes ready to adopt them when they reach an age at which they can transition to the shelter population. As shelters are successfully managing their feline populations and spay/neuter resources are helping to decrease intake, we are in a place now where saving this vulnerable population is a possibility. It is not uncommon for technicians or assistants in shelters or private veterinary practices to occasionally bring home a litter of kittens to bottle feed. It is almost a rite of passage for any young technician. Inevitably, there are a few “foster failures” in every group of veterinary professionals. When an organization decides to make saving kittens a priority, a formal foster program will make the process run smoothly without putting the burden on the shelter employees. How do shelters know if they can reasonably start a kitten foster program? First, you need the resources to care for kittens in foster. Online wish lists and “kitten showers” are excellent ways to solicit donations for fosters, but the organization needs to be able to cover all costs for the kittens in foster if donations were to cease. Shelter resource capacity also need to be considered. All animals that leave for foster will eventually need shelter services that may already be stretched. Consideration needs to be given to the capacity of the medical team to provide vaccinations, exams, treatments, counseling, and surgery. Foster kittens will also occasionally need emergency care, and if a staff member isn’t available a means to pay for emergency veterinary care will need to be in place. Next, you need to ensure every cat you put into foster will be able to find a home when it returns to the shelter. Foster parents often get attached to their temporary family member, and if your shelter is still euthanizing healthy cats for “space” it is not a good time to start a foster program. Not only do you risk upsetting the foster parents and potentially damaging the shelter’s reputation, you also expend a lot of resources on cats that may not be able to find permanent homes. If the shelter live release rate for weaned kittens is not near 100%, the focus needs to be on improving that number before trying to save neonates. If your shelter has a very high live release rate for kittens and the resources and volunteer base to run a foster program, it’s time to move on to the next step. Finding a foster coordinator early in the process is important. This can be a volunteer or a part or full time employee depending on the size of the organization. Many shelters have a very dedicated volunteer or unofficial foster parent that they can ask to coordinate the effort. This person serves as the link between foster parents and the shelter so it is important that they understand the organization and all aspects of raising foster kittens. The coordinator will also need to understand vaccination and deworming schedules so they can ensure kittens are kept up to date on preventatives. The veterinary team (with the assistance of a consulting veterinarian if the shelter does not employ one) will need to write a thorough foster manual that details care for kittens and what to do with minor maladies. Examples of emergency conditions can also be noted in this manual. A detailed foster manual that clearly defines the responsibilities, protocols, and expectations will provide clarity and minimize problems as well as liability.1 The more detailed the foster manual and the more educated the coordinator, the fewer phone calls the veterinary staff will need to field in the future. Social media has become the primary means for many shelters to recruit foster families. Referrals from friends, newspaper ads, and youth groups are other effective means for finding volunteers. It is very helpful to have those with previous fostering or animal care experience be mentors to those without as much knowledge or experience. It is also helpful to have a mix of lifestyles and personalities in your foster group. For example, and older retired person is great to have for a kitten that needs socialization and a lap to sit in much of the day but they may not want to stay up all night to bottle feed. A younger student that stays up late to study may be more equipped to take care of a bottle baby. Orientation classes are a great tool to educate foster families. Classes should be taught by a member of the veterinary staff who has knowledge of neonatal care. These presentations introduce new fosters to the organization and its mission and educate them on the importance of following the recommended guidelines. It is a good idea to teach volunteers what “normal” looks like, including going over milestone charts and describing how quickly kittens normally gain weight. This is also a good time to set realistic expectations. If the organization cannot or will not use resources for ICU care or specialized treatments, that needs to be explained up front. If kittens with significant medical issues will be euthanized rather than treated, that needs to be explained so foster families have realistic expectations before agreeing to bring home a kitten. I also recommend fosters sign a contract. This will vary depending on the type of shelter, legal requirements in your area, and the requirements of fosters. For our municipal organization, the city attorney asked that all fosters sign a contract stating that they understood the risk of zoonotic disease, that they would follow all instructions for medical care, and that they would return the kittens

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to the shelter upon request. If foster parents will be required to have their pets vaccinated or have their cats tested for FIV and FeLV this should also be in the contract. Many organizations also ask fosters to attest to not fostering for any other shelters. Once the coordinator, supplies, and families are in place, you just need kittens. In order to move the kittens out of the shelter quickly, it is good to keep a list of which foster parents are immediately available. The foster parents should know that they are next in line so they can be available to pick up kittens should they arrive. The faster kittens can get out of the shelter, the more likely they are to not develop shelter-acquired illness. Either fosters can have supplies ready at their homes or starter kits of supplies can be ready so kittens can leave quickly. Before foster kittens leave the building, it is important that they have a record at the shelter and a record that can go with the foster that includes a specific schedule of recheck appointments for that animal(s). If the shelter has computerized records, it is easy to set reminders for their vaccinations and deworming schedule and to set a tentative surgery date.

Writing foster care protocols As previously mentioned, a foster manual with detailed care instructions will aid the families in giving the kittens the best start in life while saving the veterinary staff time and resources. The foster manual needs to include housing, feeding, elimination, bathing, and socialization guidelines as well as a discussion of weight gain and milestones. It is also a good idea to provide answers to some common medical concerns and what to do in case of emergency. The most important housing concern for neonates and infants is to provide warmth. Kittens do not regulate their own body temperature well in the first four weeks of life and can only maintain a body temperature about 12 degrees higher than their environment. This is due to their large body surface area with non-cornified skin, their lack of insulating fat, and the fact that they can’t vasocontrict their peripheral vessels. Neonates are especially susceptible because they cannot shiver at birth.2 Overhead heat lamps, Snuggle Safe discs, and other commercially available sources of warmth can be used. Heating pads should be used with extreme caution to avoid thermal burns. Hypothermia has a negative impact on immunity, nursing, and digestion3 so keeping the kitten warm is vital to keeping them healthy. Fosters should also be advised to house kittens away from unsupervised access by other pets or children and in an area that can be disinfected. Nutritional support can be the greatest challenge for foster families. If a lactating foster queen is available, she is the best option for feeding orphans since she will provide nutrition as well as maternal care. Most lactating queens will accept the additional kittens, but it is important to place kittens with litters that are a similar size to avoid size discrepancy.4 Partial hand-raising is an option if a queen has recently weaned her own litter, if there is a discrepancy between the amount of kittens and the amount of lactation, or if the queen is not healthy enough to provide optimal nutrition. When orphans needs to be bottle-fed, foster homes need to be supplied with sufficient formula and bottles. Orogastric tube feeding kittens is relatively simple, and some dedicated volunteers can be trained to take kittens that require tube feeding. Specific instructions for preparing and warming the formula, feeding frequency, daily weighing and monitoring of growth, positioning during feeding, and weaning need to be written in the foster manual. Signs of feeding problems and instructions for care should also be included in these manuals. Foster parents should also be warned of the risk of feeding cow’s milk and the risks associated with over-feeding. It is not uncommon for well-meaning individuals to unintentionally cause harm. Kittens will generally start drinking formula from a dish around 3-4 weeks old. Solid food is first introduced by mixing canned food with milk replacer and offering it on a flat dish. The amount of milk replacer is slowly decreased until the kitten is primarily eating solid food. By 5-6 weeks, kittens can chew dry food and should be eating about 1/3 of their daily calories in the form of solid food.4 Dry food can be offered ad lib between meals of canned food. Weaning should be complete by 6-9 weeks old. Elimination and defecation must be stimulated in kittens less than 3 weeks old. Normally this is done by the queen when she licks the kitten’s perineum, and the foster parent needs to mimic that in young orphans. Before and after each feeding, the foster parent needs to rub the kitten’s lower abdomen, genitals, and rectum with a cotton ball dipped in warm water. Kittens typically urinate with every stimulation and defecate at least one time per day. When the kitten starts eliminating on its own, it should be given a litter box with shredded paper or non-clumping litter. Stool should be placed in the litter box until the kitten learns to eliminate in the litter box. Socialization is an important aspect of hand-rearing kittens that cannot be overlooked when developing care protocols. The sensory phase begins at approximately 3 weeks and lasts until approximately 2 months old. Opportunities to gain desirable conditioning during this time will improve the kitten’s ability to be a well-socialized companion animal in the future.5 Frequent, careful handling of the kitten is important to help it become accustomed to human handling. This becomes an important consideration when shelters attempt to socialize the kittens of feral queens admitted to the shelter. As long as the kitten is healthy and gaining weight, it should be scheduled for surgery at about 6-8 weeks old. A plan should be in place for adoption following surgery. Many shelters use fosters as the primary source of off-site adoptions rather than having them enter the shelter population. It is also common for foster parents to be adoption ambassadors and find homes for their houseguests. It is important that the population management and flow through foster homes is managed in much the same way as the shelter population as a whole. It is also important for the kittens in foster to be included in plans for shelter population if they are to return to the shelter for adoption and placement.

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Medical protocols A medical exam should be performed at the shelter before kittens are sent into foster. Exams are important for many reasons, one of which is to identify special needs cases that may need to go to foster homes more equipped to handle their needs. High risk kittens should go to homes that can provide for their special needs and could handle the loss of a kitten without mental anguish. Weighing newborn kittens will assist with determining their likelihood of survival. Normal birth weight kittens are typically 100g +/- 10g, and birth weight is the best indicator of neonatal survival. One study of 477 kittens determined that the survival rate of kittens was only about 40% while the survival rate of normal birth weight kittens was about 68%.6 For this reason, low birth weight kittens should be considered higher risk and placed in appropriate homes. Any kitten that does not have the benefit of colostrum or a replacement should also be considered high risk. Singletons can also be considered “special needs” because of the lack of a litter mate to provide warmth and socialization. If the history of the litter is unknown, singletons are also thought to carry some extra risk because infectious disease may be the underlying reason for arriving at the shelter alone.1 The initial medical exam includes a head to toe exam that checks for any congenital abnormalities. Examples of abnormalities seen in kittens include cleft palate, imperforate anus, , , and abnormally large fontanels. Congenital defects will range from very mild to those that require euthanasia. Where the line is drawn will depend on the resources available to care for the kittens as well as the availability and experience of the consulting veterinarian. Age can be estimated by using weight and milestone charts. Kittens and queens also need to be checked for overall health and any signs of infectious disease. A Wood’s lamp exam should also be performed before placing the kittens in a home.7 Queens need to be tested for FeLV and FIV before being placed in a home, and kittens should be tested for FeLV before foster when possible. A broad spectrum dewormer should be given to all kittens over 2 weeks old and repeated every 2 weeks until 2 months of age. If the kitten stays in foster beyond 2 months old, it needs to be dewormed monthly.1 Ponazuril is a useful coccidiocidal medication that can be given to young kittens before going to foster homes.8 Kittens and queens should be carefully checked for any ectoparasites. In very young kittens the safest way to manage flea infestations is to bathe and manually remove them. Fipronil spray (Frontline Spray, Merial) is labeled for use in kittens as young as 2 days old in some countries.9 If the kittens are over 4 weeks old, an MLV FVRCP vaccination should be administered. Kittens need to be revaccinated every 2 weeks while in the shelter’s care until 16-20 weeks old.10 You will need to work with the veterinarian to determine what medical issues constitute an emergency, something that needs to be examined at the foster’s next convenience, or something that can be watched at home. The clinical signs that fall into each group should be written clearly in the foster manual and explained at orientation so the families know what to do should something go wrong. It is a good idea to write basic flow charts or protocols for standard diagnostics and treatments for the most common conditions. When writing flow charts it is important to remember that neonates are not just small cats. Kittens respond to disease in a limited number of ways so treatment is often symptomatic until the underlying cause can be identified. Clinically ill neonates tend to present with some combination of hypothermia, hypoglycemia, dehydration, and hypoxia. Treating these symptoms quickly can increase the chances of survival.11Pain management is also very important in young animals because a permanent hyeralgesic response can develop without proper therapy.12Kittens respond differently to some medications, and many drugs are not labeled for use in very young animals so it is important to check with a veterinarian before administering any medications. Also, working with neonates can be frustrating. It is not uncommon for a very young animal to die and for the veterinarians to not have answers as to why. In one study, when 107 kittens and puppies 0-7 days old were submitted to the Washington State Animal Disease Diagnostic Laboratory, a definitive diagnosis for cause of death was made only 72% of the time.13We don’t always have all the answers, but this is especially true when working with our youngest and most vulnerable patients. I suggest the following resources for further information and to find accurate weight and milestone charts as well as feeding recommendations:

References 1. Smith-Blackmore, M.; Newbury, S.; Foster Care, in Shelter Medicine for Veterinarians and Staff 2nd Ed. Miller, L. and Zawistowski, S., Editors. 2013, Wiley-Blackwell: Ames, Iowa. P. 495-513. 2. Thomovsky, E.; What to expect in a neonatal kitten or puppy. Proceedings of the NAVC Conference Small animal and exotics edition 2015, Book 1 & Book 2; 29: 1087-1089. 3. Davidson, A.; Neonatal : improving the outcome. Veterinary Clinics of North America, Small Animal Practice 2014; 44.2: 191-204. 4. Little, S.; Successful management of orphaned kittens. Journal of Feline Medicine and Surgery 2013; 15.3: 201-210 5. Fraser, A.; Play and the Steps Through Life, in Feline Behaviour and Welfare. Fraser, A., Editor. 2012, CABI: Wallingford, UK P. 30-40. 6. Lawler, D.; Monti, K. ;Morbidity and mortality in neonatal kittens. American Journal of Veterinary Research 1984; 45.7: 1455- 1459. 7. Newbury, S.; Moriello, K. A. Feline dermatophytosis: steps for investigation of a suspected shelter outbreak. Journal of Feline Medicine and Surgery 2014; 16.5: 407-418. 900

8. UC Davis Koret Shelter Medicine Program. Use of Ponazuril for Treatment of Coccidia in Kittens and Puppies. Available online: http://www.sheltermedicine.com/library/use-of-ponazuril-for-treatment-of-coccidia-in-kittens-and-puppies (Accessed 6 May 2016). 9. http://www.frontlineplus.com.au/Products/Pages/product-cat-spray.aspx 10. Scherk, M.; Ford, R.; Gaskell, R.; et al. 2013 AAFP Feline Vaccination Advisory Panel Report. Journal of Feline Medicine and Surgery 2013; 15.9: 785-808. 11. Meade, C.; Fading syndrome in kittens. In Practice 2014; 36.6: 266-268, 271, 274, 276. 12. Mathews, K. A.; Pain management for the pregnant, lactating, and neonatal to pediatric cat and dog. Journal of Veterinary Emergency and Critical Care 2005; 15.4: 273-284. 13. Young, C.; Haldorson, G.; Memon, M.; Diagnosis of canine and feline neonatal death: a retrospective study of 107 cases (2000- 2010). Clinical Theriogenology 2015; 7.1: 53-58. 14. University of Wisconsin Shelter Medicine Lecture Series “Caring for Underage Kittens”: http://videos.med.wisc.edu/uwvetmedsheltermedicine 15. ASPCA Professional (examples of foster contracts, applications, manuals): http://aspcapro.org/foster-care 16. UC Davis Koret Shelter Medicine Program “Guide to Raising Orphan Kittens”: http://www.sheltermedicine.com/library/feline- guide-to-raising-orphan-kittens

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Fluid Therapy in Horses: Catheters and Nasogastric Tubes Kira Epstein, DVM, DACVS, DACVECC University of Georgia Athens, GA

Placement of an intravenous catheter and nasogastric intubation are two important technical skills in equine medicine. Intravenous catheters should be placed for relatively frequent, repeated boluses or constant rate infusions of intravenous medications and fluids. Nasogastric intubation should be performed as a diagnostic tool in horses with signs of colic and can be used for administration of large volumes of medications, nutrition, or fluids into the stomach. Intravenous catheters can be placed easily placed in several vessels in the horse. They are most commonly placed in the jugular vein, which is a central vein, and are therefore “central lines”. This means that it is safer than peripheral vessels to use for large volumes and more irritating and concentrated medications. Other locations that are used for catheter placement in horses include the lateral thoracic vein, cephalic vein, saphenous vein, and digital veins. Typically, these vessels are not used for routine medication and fluid administration unless there is a problem with the jugular vein(s) (i.e. thrombosis) or another medical reason to avoid use (i.e. cellulitis or subcutaneous emphysema obscuring the vessel). The vessels in the limbs may also be used specifically for administration of antimicrobials or analgesics regionally (intravenous regional limb perfusion [IVRLP]). Placement, use, and monitoring of the catheter are fairly similar regardless of the location. There are several types of catheters that influence the method of placement. I will discuss over the needle, over the wire, through the needle/pull away catheter. Intravenous catheters can be made of a variety of materials. These materials vary in their stiffness and reactivity, which play a role in their thrombogenicity. More thrombogenic catheters are only for short-term use. Available catheter materials, from most thrombogenic to least, include fluorinated ethylene propylene (FEP), polytetrafluoroethylene (PTFE), polyurethane, and silicone. Many of the catheters used in equine hospitals are made of FEP (short-term) or polyurethane (long-term). Prior to placement, the site should be aseptically prepared. I generally recommend clipping if the catheter is going to be in place for more than a single injection. While catheters can be placed without local anesthetics, it is often easier, particularly in young animals and when sites other than the jugular vein are used, to place a bleb of local anesthetic. I also recommend placing the catheter wearing sterile gloves. It is possible to place an over-the-needle catheter sterilely without sterile gloves, but it is not possible with other the other types of catheters. Once prepared, regardless of the type of catheter, you must feel confident about the location and have the vessel well distended. If you are going to have to distend the vessel manually for yourself and you need to keep both hands sterile, you must either prepare an enlarged area or used a knuckle or the back of your hand for distension. As noted, placement technique will depend on the type of catheter being used: Over-the-needle: The catheter comes over a needle that is the same length (a little longer) as the catheter and serves as a stilette. To place the catheter, the needle and catheter are put through the skin and into the vessel together. Getting into the vessel may require a quick, jabbing motion as it often moves away. Once you feel that you are in the vessel, you should check for a flash back of blood. The catheter and needle combined should then be advanced several centimeters to make sure the catheter is well seated in the vessel. Then, the needle/stilette should be held in place and the catheter fed off of the needle into the vessel. Over-the-wire (modified Seldinger): A flexible catheter is placed into the vessel over a guidewire. To begin, a needle or short over-the-needle catheter is placed into the vessel, well seated. A long guidewire is then placed through the needle or catheter. The needle or catheter is then removed being careful to NEVER let go of the guidewire. If necessary a vessel dilator is passed over the guidewire and into the vessel (bleeding will increase) being careful to NEVER let go of the guidewire. The catheter is then threaded over the wire and the wire is removed. Again, be careful to NEVER let go of the guidewire. Through-the-needle/pull away catheter: A flexible catheter with a guidewire to make it more rigid is passed into the vessel through a needle or pull away catheter. To begin, a needle or short over-the-needle pull away catheter is placed into the vessel, well seated. A flexible catheter with a guidewire is passed through the needle or pull away catheter into the vessel. If a needle is used then the catheter hub is seated in the needle hub, the needle is pulled out of the vessel and a guard is placed over the needle to prevent cutting the catheter and the stilette is removed. If a pull away catheter is used, that catheter can be pulled apart leaving the catheter and stilette in place. The stilette is then removed. Once placed, catheters should be flushed, usually with heparinized saline, to maintain patency every 6 hours. They should be monitored at those times for any signs of catheter site infection or vessel thrombosis/phlebitis. Catheter caps should be changed daily. It is important that catheters remain are clamped and capped when not in use and/or have a one-way valve in place to prevent . Particularly in the jugular vein, a large amount of air can be sucked into the vessel rapidly. A designated catheter or catheter port that is handled aseptically should be used if partial or total parenteral nutrition is being administered. As noted above, indications for an intravenous catheter are the need for relatively frequent, repeated boluses or constant rate infusions of intravenous medications and fluids. Catheters can also be used in some cases for sampling blood if an appropriate discard

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sample is taken to avoid contamination. CRIs can be administered with a syringe or fluid pump for smaller volumes or based on a drip rate for large volumes (>999 ml/hr). Intravenous administration of fluids is indicated if rapid correction of intravenous volume or electrolyte/acid-base imbalance is required or if the oral/nasogastric route for fluid administration is not an option. The most common indications for rapid, emergency fluid therapy are conditions that result in shock associated with decreased stroke volume due to decreased preload. Preload must be restored rapidly in order to prevent progression to decompensated shock and death. Shock occurs when the energy needs of cells are greater than the energy being delivered by the blood. Most commonly, there is a deficiency in oxygen delivery. Oxygen delivery is a product of oxygen content and cardiac output. Oxygen content is primarily dependent on [Hb] and SpO2 and cardiac output is the product of heart rate and stroke volume with stroke volume determined by preload, afterload, and contractility. Although conditions that affect either component can result in shock, in horses it is more common for shock to be caused by decreased cardiac output. Specifically horses are affected by conditions that result in decreased preload. The two main types of shock seen in horses that are due to decreased preload are hypovolemia and maldistribution of fluids. Examples of hypovolemic shock are hemorrhagic shock and fluid loss associated with large volume diarrhea or nasogastric reflux. Examples of maldistributive shock are endotoxic and that result is massive vasodilation and venous pooling of blood. Clinical signs of hypovolemic and maldistributive shock are similar and associated with poor perfusion and decreased intravascular volume as well as the body’s attempts to improve oxygen delivery. Physical examination findings associated with poor perfusion and decreased intravascular volume are cool extremities, prolonged jugular refill, prolonged capillary refill time, poor pulse quality, and decreased/absent urination. Physical examination findings associated with the body’s attempts to improve oxygen delivery are increased heart rate, increased respiratory rate, decreased/absent urination, and production of concentrated urine. If available, hand held lactatometers and/or blood gas monitors can be used to assess plasma lactate concentrations to support inadequate oxygen delivery. The goal of emergency fluid therapy is rapid restoration of preload, cardiac output, and oxygen delivery. This requires use of the intravenous route of fluid administration. A wide diameter (10-14g), short catheter with large bore fluid administration sets will maximize the speed of delivery. Depending on the type of fluid chosen and packaging, pressurized administration may be possible. The two main alternatives for rapid volume resuscitation are: 1) using a relatively small volume of hypertonic saline (2-4 ml/kg or 1-2 L/adult horse [not generally recommended in foals]) and/or synthetic colloids (5-10 ml/kg or 2.5-5 L/adult horse or 250-500 ml/foal) to borrow/pull fluid from the interstitium into the vascular space followed by administration of larger volumes of isotonic crystalloids (at least 20 ml/kg) or 2) using isotonic crystalloid fluid alone. In either case, the “shock dose” of 80-90 ml/kg can be used as a guideline for the maximum amount of isotonic crystalloids to administer as a bolus. In general, it is rare to need the entire “shock dose”. I recommend starting with a 20 ml/kg bolus (10 L/adult horse or 1L/foal), reassessing clinical signs/physical examination parameters, and determining if additional boluses are required. In horses with diseases that are associated with protein loss, the use of colloids in the resuscitation plan might have additional benefits. In the case of hemorrhagic shock, should be considered as part of the fluid resuscitation plan. Nasogastric tubes also come in a variety of shapes and sizes. In most cases a fairly large diameter, firm tube will be used, but for more longterm use (i.e. feeding tubes), small diameter, flexible tubing with a stilette for placement is preferable. It is of vital importance to check for two things prior to administration of any medications or large volumes of fluids: you are in the right place (stomach, not lungs) and there is no significant (>2L net) reflux present. When passing a tube there are several ways to check that you are in the right place—you can often see the tube pass down the left side of the neck in the esophagus, you may be able to feel the tube in the esophagus (if it is in the trachea and you shake it, it will rattle), there is negative pressure in the esophagus, and the stomach should have gas/contents. With a smaller, more flexible tube, these things may be more difficult to assess. In these cases, radiographs are the most accurate way to confirm placement. Proper restraint is key to successful, safe nasogastric intubation. Physical restraint methods such as twitches or stocks may be adequate, but sedation should be used if necessary. Local anesthetic lubricant is available, but if it reaches the larynx it will make it difficult to get the horse to swallow. The most sensitive, and therefore most objectionable, part of passing a nasogastric tube for the horse is through the nasal passage. This should be done as quickly and smoothly as possible. Prior to passing the tube, get an idea of how far in you will have to go to get to the pharynx (you can measure from the nostril to the medial canthus of the eye or empirically in an adult horse its about 8-12 inches). The tube must be directed VENTRAL and CENTRAL (medial) through the nasal passage. Your hand should be placed over the horses nose with the thumb holding the false nostril out of the way and pushing the tube VENTRAL and CENTRAL. Be careful not to occlude the other nostril. If you run into a firm/boney structure it is the ethmoids— don’t keep pushing or you will get a pretty good nosebleed. In order to encourage the tube to go to the esophagus rather than trachea, keep the horse flexed at the poll. Horses will often swallow immediately as you get back to the larynx. If not gently “bumping” the larynx will generally encourage them to swallow. Be patient, but if it does not seem to be working, try going up the other nostril. When using small, flexible tubes, sometimes it is very difficult to get the horses to swallow. You can use an endoscope to confirm/assist placement in these cases.

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As noted above, indications for nasogastric intubation include a diagnostic tool in horses with signs of colic and administration of large volumes of medications, nutrition, or fluids into the stomach. Oral fluids are at least as effective as intravenous fluids for correcting dehydration and maintaining hydration. They are less expensive and do not have the risk of vascular complications. Administration of fluids required for a 24-hour period can be dividing into multiple doses throughout the day or given as a constant rate infusion via nasogastric tube. No more than 6-8 L of fluids should be given at one time point. There are three main components to consider when calculating the volume of fluid for a 24-hour plan: maintenance, dehydration, and ongoing losses. In adult horses, maintenance requirements are 50 ml/kg/day and in foals, maintenance requirements are 80-100 ml/kg/day. In horses, estimating dehydration is very difficult. Traditional clinical signs of dehydration such as skin tent and dry/tacky mucus membranes have been shown to be completely inaccurate. Ongoing losses may be easy to measure, such as with horses that are producing nasogastric reflux, or difficult to determine, such as with horses with diarrhea or polyuria. Nasogastric tube administration is commonly used for treatment of horses with large intestinal impactions. There are several mechanisms of action that cause loosening and/or softening of gastrointestinal contents by laxatives. Laxatives used in horses include bulk laxatives that provide volume and help retain water (psyllium), surfactants that help incorporate water and fat (dioctyl sodium sulfosuccinate [DSS]), lubricants that are slippery and decrease water absorption ( oil), and hydrating agents that help attract and retain water (isotonic balanced electrolyte solution or magnesium sulfate). DSS can be irritating and may facilitate the absorption of mineral oil or magnesium sulfate and associated toxicities. Overdoses of magnesium sulfate alone can also result in magnesium toxicity. An isotonic balanced electrolyte solution has been shown to result in the largest increase in fecal water. Water has also been shown to effectively hydrate ingesta. Psyllium is frequently used for the prevention and treatment of sand impactions. Mineral oil can be used as a marker for intestinal transit in addition to it’s laxative activity.

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Talking Toxic: Things Technicians Need to Know about Toxicology and Common Intoxications Tim Evans, DVM, PhD, DACT, DABVT University of Missouri Columbia, MO

The goal of this lecture is to provide veterinary technicians with important information pertaining to veterinary toxicology, in general, several small animal intoxications, specifically, and currently available toxicology-related electronic resources.

In this presentation we will review the following  Some fundamental veterinary toxicologic definitions and principles  The basics of the clinical management of suspected veterinary intoxications  A discussion of several “common” small animal intoxications  General veterinary toxicology electronic resources

Fundamental definitions for veterinary toxicology  Toxicology-The study of poisons→Poison-Any solid, liquid or gas, which can, in sufficient quantities, adversely affect a biological system  Toxin-A poison of biological origin  Toxicosis-The state of being intoxicated  Dose-The terms for the total amount of a toxicant to which an animal is exposed  Dosage-the amount of toxicant per unit body weight, often per unit of time

Basic principles of veterinary toxicology  “The Dose Makes the Poison.”→Dose-Response Relationship-Generally, the greater the dose/dosage of a given toxicant, the more severe the clinical signs→Exposure to toxicants and/or their metabolites must be sufficient to cause intoxication.

OVERVIEW of basic clinical management of suspected intoxications REVIEW of basic workup of a suspected intoxication (“malicious” OR “accidental”  Often an EMERGENCY!!! o Simultaneously incorporates aspects of treatment and diagnosis o FIRST THINGS FIRST/MOST CLIENTS PREFER PET SURVIVAL OVER CONFIRMED Dx!!! . Determine what is in “Toxicant X” (NEED LABELS)/Jump right to treatment??? o Possible rationale for having yourself or technicians cloned!!!  Signalment + Clinical Signs/Clinical Circumstances o WHICH PETS (names, breeds, ages+)?/WHAT ARE THE CLINICAL SIGNS??? (video?) o Exposure to “Toxicant X”→≈HOW MUCH?/WHEN?/WHERE? (How reliable is info?)  Problem List o WHAT’S WRONG? SOME CLINICAL SIGNS “TOXICANT X” SPECIFIC/SOME GENERIC o Physical examination and STAT laboratory testing, IF proximate to patient  “BIG PICTURE” PROBLEMS o SUMMARY OF CRITICAL LIFE-THREATENING ISSUES AND TARGET SYSTEMS/ORGANS . TREAT THE PATIENT NOT THE POISON, UNLESS TOXIC EXPOSRE OBSERVED!!! . STABILIZATION OF THE PATIENT IS NUMBER ONE PRIORITY!!! OVERVIEW of Basic Clinical Management of Suspected Intoxications (CONTINUED) REVIEW of Basic Workup of a Suspected Intoxication (“Malicious” OR “Accidental”/continued):  D.A.M.N.I.T. o D = Degenerative o A = Anomaly o M = Metabolic o N = Nutritional/Neoplastic o I = Infectious/Inflammatory/Idiopathic o T = Traumatic/Toxic

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 POISONING SHOULD BE SUSPECTED WHEN: o DIRECTLY OBSERVED TOXIC” EXPOSURE/”TOXICANT X” IN VOMITUS OR GI TRACT o Sudden death/Similar clinical signs in MULTIPLE animals o Rapid onset of afebrile syndrome or sudden death of a previously healthy animal. o Signs of unknown etiology/Other causes ruled out o Recent change in diet or environment o Neighborhood feuds/Love gone bad/Pet owner often certain of “CULPRIT” o Very small, young, mean, noisy, annoying, and/or stupid animals!!! o Might be a “Darwinian phenomenon” OR “aliens”, “bikers”, “local meth labs” o IF “OBVIOUS” INTOXICATION, GO IMMEDIATELY TO EMERGENCY Rx!!!  ONCE ANIMAL STABLE/DIAGNOSIS STILL UNCERTAIN: CONTINUE STEPWISE WORKUP  List plausible toxic/Some not so toxic differentials  Most likely FINAL “Toxic” diagnosis and WHY IS IT “TOXICOSIS X” o Not always possible to CONFIRM Dx/Looking and acting like “Dx” might be sufficient.  Helpful to know toxic mechanism(s) of action (MOA) of “Toxicant X” o Good correlation of “Toxicant X”MOA with Problem List supports “Toxicosis X” Dx o Can incorporate knowledge of toxic MOA into successful treatment plan  “Toxicosis X” successfully treated/Diagnosis of “Toxicosis X” confirmed o Sometimes not possible to do both/“Toxicosis X” Dx confirmed by laboratory testing

DETAILED clinical management of a suspected intoxication, including Rx/Dx EMERGENCY Rx/TREATMENT of suspected intoxications  REMOVE THE ANIMAL(S) FROM THE SOURCE OF “TOXICANT X”!!! o MIGHT BE REMOVAL OF THE SUSPECTED “TOXICANT X” SOURCE FROM ANIMAL!!! . Baths for cutaneous exposures to “Toxicant X” (especially the paws of cats) . IF “X” eaten, Emesis/GI lavage or containment/Activated charcoal ± Cathartics o House/Garage/Kennel/Yard/Junk management  IMMEDIATE VETERINARY CARE!!! o TREAT PATIENT NOT THE POISON, UNLESS “TOXICANT X” EXPOSURE OBSERVED!!! o STABILIZATION ABCs . Airway/Breathing/Circulation/Depression/Excitation/Fever/Hypothermia o Supportive care  Decontamination/Antidotal therapy AND/OR Lipid Infusion for specific Intoxications o Decontamination is ANOTHER way to separate the source from the animal!!! o Depends on route of exposure/Stage of intoxication/Specific antidote (IF available) . Bath for cutaneous exposures to “X”/Emesis+ IF NO contraindications (“X” eaten)

DETAILED clinical management of a suspected intoxication, including Rx/Dx (CONTINUED) Some “guidelines” for stabilization ABCs  Ensure that the Airway is patent o Awareness of obstructions/bronchoconstriction  Establish normal Breathing o Awareness of breathing problems/impaired gas exchange  Correct Circulation deficits o Fluid/Electrolyte/Acid-base imbalances + various anemias with different etiologies  Control Depression of CNS o Correct metabolic disturbances/neurotransmitter imbalances  Control Excitation of CNS o Do nothing if very mild o Correction of electrolyte imbalances and possible glucose deficits o Anticonvulsant medications  Bring down Fever o Avoid use of NSAIDs for toxicant-induced hyperthermia  Treat Hypothermia o No ice water baths 906

Supportive care  Maintenance of vital functions/fluid therapy o Might also be used in stabilization  Antibiotics/Analgesics/Diet modifications/Client communication/Client education Patient stabilized/Dx uncertain→fine-tuned clinical signs/clinical circumstances reassessment  Might be onsite/animal side in clinic/remote by telephone, text, or ??? o Access to both premises and animals is ideal!!!  A thorough and accurate history is often the key!!! o Prevents the chasing of many wild geese AND “innocent” parties!!!  Information might be relayed by phone or be secondhand. o The accuracy of such information might be questionable OR “slightly” exaggerated!!!  Asking the right questions is extremely important!!! o Might need to ask the same question several different ways!!! o Might need to seek out the individual really in the know OR the “CULPRIT”!!!  A good physical examination is of critical importance and may need to be repeated!!! o It is perfectly ok to use a stethoscope and a thermometer!!!  So is careful observation of clinical signs/circumstances!!! o Direct observation of patient might yield very different information!!!! o Impacted by scheduling/ lighting/finances/crowds/decomposition/”karma”!!!

CONFIRMING diagnosis of suspected intoxications (NOT ALWAYS POSSIBLE)  DIRECT OBSERVATION OF “TOXIC” EXPOSURE/”TOXICANT X” IN VOMTUS OR GI TRACT  PRETTY MUCH TRUMPS EVERYTHING ELSE IF “TOXICANT X” IS IDENTIFIABLE  BRING IN CONTAINERS/LABELING/MSDS/ANY AVAILABLE DOCUMENTATION  MIGHT BE ALL DONE WITH Dx/EXCEPT ”LEGAL” CASES REQUIRING Dx CONFIRMATION “Common” small animal veterinary intoxications  Antifreeze o Poison o Patients o Pathogenesis o Problems o Plan  Chocolates, Energy Drinks, and Sugar-free Gum o Poisons o Patients o Pathogenesis o Problems o Plan  Mouse, Rat, Gopher, and Mole Baits o Poisons o Patients o Pathogenesis o Problems o Plan  “Legal” and Illegal Drugs o Poisons o Patients o Pathogenesis o Problems o Plan

Veterinary poison control center websites  http://www.petpoisonhelpline.com/separate tabs for pet owners and veterinarians  https://www.aspca.org/pet-care/animal-poison-control for pet owners  http://aspcapro.org/poison for pet professionals 907

 Phone apps available and phone consultations available on a fee for service basis

U.S. FDA website providing helpful information for pet food recalls  http://www.fda.gov/AnimalVeterinary/default.htm o Website for Food and Drug Administration o Go to Animal & Veterinary tab for veterinary drug-specific information o Useful regulatory information on pet food contaminants/recalls o Mechanism for reporting adverse drug reactions/pet food-related incidents o Other helpful information on veterinary medications o Also useful information on human medications

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Farm Animal Pet Medicine Phillipa Gibbons, BVetMed, MS, MRCVS, DACVIM Texas A&M University College Station, TX

Farm animals (small ruminants, camelids and pigs) are increasingly being kept as pets. This means that farm animals may be treated by urban and small animal veterinary clinics. This article will cover important aspects of management and common diseases. In general most diseases of farm animals are as a result of incorrect management and/or nutrition. While these animals are kept as pets, the laws regarding drug use in food animals must be followed. More information regarding appropriate use of drugs in food animals can be found on the Food Animal Residue Avoidance Databank website www.FARAD.org.

Pigs Pet pigs come in a variety of shapes and sizes. The majority of pet pigs are still the Vietnamese Pot Belly pigs that weigh over 100lbs at mature weight. Mini pot belly pigs are supposed to reach a maximum weight of 60lbs and teacup or micro pigs 30lbs mature weight. However, due to breeding, the mature weight of these smaller pigs may not be consistent. Other pet pigs seen in the veterinary clinic are commercial swine breeds and Kune Kune pigs (originally from New Zealand). Occasionally wild hogs may be kept as pigs, however, due to disease risks to humans and domesticated animals this cannot be recommended. Due to the fact pigs are commonly kept as pets, they are often presented to small animal veterinarians. The Food and Drug Administration considers them food animals, and therefore drugs prohibited in food animals should not be administered. The lifespan of pot belly pigs is approximately 15-20 years. A good source for pet pig drugs and dosages is the Exotic Animal Formulary by Carpenter 4th Edition or the Bayer Compendium of Veterinary Products where one can find drugs labeled for use in pigs. Smaller pigs can be held or restrained and lead using a dog harness. Larger pigs may need to be restrained using a pig board. Snares should never be used on pot belly pigs as their nasal bones can easily be broken. Routine care As with other species, it is recommended to vaccinate pot belly pigs. We recommend vaccination against Erysipelas, the respiratory diseases (including Actinobacillus Pleuropneumoniae, Bordatella bronchiseptica, Haemophilus parasuis and Pasturella multocida) and leptospirosis. Vaccines require 2 initial doses followed by yearly boosters. vaccination with IMRab3 is also commonly administered, although the risk of rabies is low in pigs. The dose and route of administration should be followed as per the label. Decreasing the dose in smaller pigs is not recommended. Owners should be warned for adverse reactions and veterinarians and technicians prepared for anaphylaxis, although the risk is very low. Pigs that have access to outside should be wormed regularly for roundworms. Ectoparasites (mange) is common in pet pigs. It is recommended that all pet pigs be castrated or spayed. Castration is important for behavioral control, and spaying to prevent uterine tumors and unwanted . Castration can be performed from a few weeks old under local anesthesia and sedation or general anesthesia. Closed castration with skin closure should be performed. Ovariohysterectomy is recommended at around 3-5 months old and is performed under general anesthesia. Depending on the living environment of the pig, foot trimming may need to be performed every 3-12 months. It is important for the owner to initiate this early in life to make is as low stress as possible for the pig (and the technician!). The pig should have access to concrete areas or other rough surfaces to help wear down the hoof. For pigs that require foot trimming in a veterinary clinic, it is recommended to perform this under general anesthesia. Sheep foot trimmers or a dremmel tool work well to trim feet. Pigs ears may need to be cleaned routinely. Use cleaner labeled for dogs on cotton wool or gauze, avoid putting fluid into the ear due to the difficulty in draining the ear, resulting in temporary deafness or head tilt. Nutrition Good nutrition is paramount in pet pig care due to the ease they can become obese resulting in lameness, skin and eye issues. There is proprietary pet pig food available which should be fed by weight at 1-2% of body weight. The diet can be supplemented with green leafy vegetables and grazing grass. Fruits can be offered in smaller quantities. Human food should not be fed, especially foods high in salt. The body condition and weight should be monitored regularly and the diet adjusted accordingly. It is recommended to feed the youth feed until 18-24 months old, as this formulation has essential nutrients needed for growing pigs (e.g. lysine). After this time the adult or senior diet can be fed. The senior diet has a lower calorie content and may need to be introduced earlier in cases of obesity. Many piglets are weaned early (< 4 weeks old) for their new owners to continue to bottle feed and ‘bond’. This often results in a significant dietary change and stress leading to disease. We recommend that pet pigs are not weaned until over 4 weeks old and appropriate transition to a solid diet occurs. For orphan pigs, pig milk formula may be available. In the absence of this, goat milk formula is appropriate. Fresh water should be available at all times, especially important in the Summer due to the risk of salt toxicity.

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Housing Pet pigs should always have access to the outdoors, since their rooting behavior can be strong. If kept alone and unsocialized they can develop behavioral issues. They should have adequate shade, fans and pools to keep cool in summer as temperatures above 85F can be stressful. Pigs are exceptionally clean animals and will not voluntarily urinate and defecate in their ‘sleeping’ area. They can be litter box trained. Exercise is important for mental stimulation and prevent obesity. It must be stressed to future owners that keeping a pet pig, especially as a single indoor pet, requires as much work as a dog. Since pigs are classed as food animals, some home owners associations will not permit them. Medications Injections should be given intramuscularly in the neck in all pigs. Intravenous access is best gained by the ear veins. 18 – 22 gauge catheters are appropriate sizes. In old, very small or debilitated pigs where intravenous access is difficult, the intraosseous route can be used for fluid therapy, intravenous medications and euthanasia. A 14-gauge needle can be inserted in the tuba coxae, or an intraosseous catheter used. Due to their single stomachs, oral medications can be administered even in adult animals. Common diseases Erysipelas - Younger pigs commonly present with fever initially, the classic diamond skin lesions develop later. Heart and joint disease can occur with chronic infection Obesity - a major cause of poor health in pet pigs, predisposing to joint conditions, skin disease and blindness caused by the overhanging ocular fat pad. An ideal body condition is 3/5. Osseous Chondritis Dessicans (OCD) - This disease is more commonly seen in show pigs that are fed high energy and protein diets. The bone outgrows the blood supply to the cartilage resulting in localized cartilaginous necrosis and bone cysts. The pig usually presents with lameness. Radiographs may provide a diagnosis. Treatment is not always effective, but the protein content of the diet should be decreased. Non-steroidal anti-inflammatories are indicated in the short term. Polysuflated glycosaminogylcans (Adequan) can be used weekly also. Arthritis - is common in older pigs. and is the most common reason for euthanasia in our clinic. Pigs are naturally clean animals and when they cannot be clean they can become very distressed. Non steroidals, opioids and joint supplements can both be used long term to control pain. Squamous cell carcinoma - This is a common skin disorder of older pigs with white skin. If white (or spotted/paint pigs) are kept outside, it is recommended to use suncream (non zinc oxide based) as a preventative measure. Usually presents as multiple raised ulcerated areas. Typically unless these areas become infected they do not appear to affect the pig. There are usually numerous lesions making surgical removal difficult. Diarrhea - Infectious causes are more common in younger pigs. Nutritional diarrhea is not uncommon due to dietary indiscretion. Typically, in nutritional diarrhea, the pig is bright and alert with good appetite. Dippity Pig - This disease is actually erythema muliforme. It is more common in younger pigs in warmer weather and stressful conditions. It causes acute pain and skin lesions. The condition will spontaneously regress, however antibiotics and steroids can be used. Sunburn can also present with similar signs, therefore a detailed history should be taken. Skin diseases - many pot belly pigs have dry flaky skin. These can be removed with wet towels and moisturizing lotions applied. Fatty acid supplementation can be used, but care must be taken not to contribute to obesity. Pigs can have lice and sarcoptic mange. Injectable ivermectin is effective for both conditions. Greasy pig disease (Staph. Hyicus) may occur secondary to mange infestations. Urolithiasis - both males and females can develop uroliths, however obstruction occurs in males. Diagnosis of urolithiasis can be performed by ultrasonography and/or radiographs. Treatment includes both medical treatment with urinary acidification and surgical methods.

Small ruminants Small ruminants kept in urban environments may actually serve as more than just pets, including milk for human consumption, wool or meat. Therefore, it is important to establish the use of the animal before treatment is initiated and withdrawal times established. Nutrition A ruminant’s diet should consist primarily of forage (hay or grass), and supplemented only with a concentrate (grain) feed as necessary to maintain body condition. It is important to remember that body condition must be performed ‘hands on’ in small ruminants and not by sight, especially in wool breeds. All feeding changes should be made gradually, over 10-14 days. This will prevent diseases such as rumen acidosis. In general, most pet ruminants that are not productive (growing, lactating, pregnant or breeding) can maintain their body condition with forage alone. It is recommended that if a higher energy or protein diet is required, this is provided by a commercially available feed formulated for that species. This is especially important for sheep, due to higher levels of copper in other species’ feed. A mineral supplement (loose mineral is preferred over blocks) should be available at all times. Fresh water should be available at all times. Goats in particular, can be picky about drinking water. It is important to encourage them to drink by providing cool fresh water (or warmed water during extremely cold periods) to prevent urolithiasis in males.

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Routine management It is recommended that male pet small ruminants are castrated to prevent undesirable odors and behavior. Pets should be castrated as late as possible (4-6 months old) to allow the urethra maximal development which may help reduce incidence of urolithiasis. At 6 months old some breeds (Pygmies and Nigerian Dwarfs) may be sexually mature. At this age, castration should be performed surgically by a veterinarian under sedation/general anesthesia with systemic or local analgesia. Uterine tumors do occur in older females and a syndrome of inappropriate lactation is common in small breed goats. Therefore, pet female goats and sheep may be ovariohysterectomized under general anesthesia. Essential vaccines for all small ruminants include and Clostridium perfringens type C and D. This should be performed at 8 weeks old (if the dam was vaccinated 4-6 weeks prior to kidding) and a booster vaccine given 4 weeks later then annually thereafter. Any animal with an unknown vaccine history should be given ‘CD&T’ vaccine in 2 doses to start. Rabies vaccination can also be given. Other vaccines including respiratory, orf, foot rot, caseous lymphadenitis should only be given if there has been documented disease and under the recommendation of a veterinarian Parasite control Due to the significant presence of resistant parasites to all classes of anthelmintics, sustainable control of parasites is recommended. In brief, this program means that only those animals that need treating with an anthelmintic (deworming) are given the drug which is most likely to be effective. FAMACHA (ocular mucus membrane color), body condition, fecal consistency, fecal egg counts should be used to determine which animals need treating. Haemonchus contortus (barber pole worm) that causes anemia and Telodorsagia and Trichostrongylus that cause weight loss, bottle jaw and diarrhea are the most common nematodes of small ruminants and camelids. Key points to note are  Goats and camelids require higher dosages of dewormers than sheep  When diagnosing and managing parasites a quantifiable egg per gram count (e.g. McMasters) is used rather than a fecal float  AMDUCA regulations should be followed when choosing an anthelmintic to use and appropriate withdrawal times (according to FARAD) are used  Oral dewormer should be used. Injectable and pour on formulations are more likely to contribute to resistance.  Accurate body weight determination is necessary to prevent underdosing and drug resistance  More information can be found on the website of the American Consortium of Small Ruminant Parasite Control (www.wormx.info). It is recommended that veterinarians and technicians become familiar with sustainable parasite control as management of parasites has, and is, changing, and clients need to be kept updated. Foot trimming Depending on the breed, the animal’s and area where they are kept, sheep, goats and camelids need to have their feet trimmed routinely. Only excess hoof wall should be removed, aggressive foot trimming can result in granuloma formation and lameness. Shearing A significant problem in camelids kept in Texas (and the rest of the Southern USA) is heat stress. We recommend that camelids (alpacas and llamas) are sheared twice, once at the start of the warm weather (April) and again in late Summer (August). Veterinarians may be called upon to perform shearing. Wooled sheep need adequate shade and fans during the summer, and shearing before the start of the warm period. Hair sheep can more easily be managed in the climates of the Southern USA. Common diseases Some of the more common presentations of disease that are seen in pet small ruminants include inappetance/general malaise diarrhea, bloat, straining to urinate (the owner may recognize this as straining to defecate), and neurological disease. Common diseases include coccidiosis (in younger animals), gastrointestinal parasitism (Haemonchus presenting with anemia and weight loss, or Telodorsagia presenting with weight loss and diarrhea), grain overload (may present with bloat, diarrhea, inappetance), copper toxicity (presenting with malaise, pigmented urine) and polioencephalomalacia and urolithiasis. As a general rule, all sick male castrated animals should have urolithiasis considered as a differential until they pass a normal stream of urine. Copper toxicity is more common in sheep, as they have a lower tolerance level. Sheep that have access to pig, goat, cattle, horse or poultry feed are at risk of copper toxicity. Copper toxicity causes hemoglobinuria, with secondary renal failure and anemia. Due to the common occurrence of rumen acidosis (grain overload) it is advised to pass a tube and check rumen pH (normal is 7) (and protozoal activity under a microscope on low power if possible) in all sick ruminants. Polioencephalomalacia presents with stargazing and blindness (absent menace response but present pupillary light reflex).

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Head Tech Headaches: No One Supports, Listens, or Backs Me Up (and How You Can Fix Things) Bash Halow, CVT, CVPM Halow Tassava Consulting Wyalusing, PA

One of the biggest, albeit innocent, errors in veterinary management is to appoint a person the head of a technical department and not give them clear goals, capable team members, or the support they need to accomplish the job at hand. Before supervisors appoint a head tech, before the technician accepts the job, or even if you’re already deep into your role, the following points should be considered.

The value of planning and regular communication An organization on target to succeed is one that has a mission and goals. Mission statements have been discussed for such a long time, but implemented so poorly in most practices, that many veterinary professionals dismiss them as unnecessarily mumbo jumbo with no real relevance to the practice’s day-to-day work. What a shame! Mission statements, when given proper thought and exercised correctly in the practice, can be the beginning of a remarkable success story: a story of you and your team and the journey, effort and outcomes that you not only aspire towards, but achieve. They begin a dialogue on expectation and serve as a sounding board for every management decision in the building. Mission Statements level tyrants because they stand for the place of employment, not the employer. They ground us in what we want to work for, not what we have to do. I can’t emphasize the value of mission statements enough and a bit of me dies every time I’m lecturing on the topic and the eyes of attendees glaze over. In the presentation in Kansas and San Diego, I’ll do my best do entertain, shout and rant on the topic. In the meantime, please go to www.dvm360.com and search for Bash Halow. In there, you’ll find a link to resources that I’ve built that will help you and your team explore the mission statement and your practice’s reason for being in general. Mission statements precede another vital and key component of successful leadership: goals. Having outlined in the mission what you one day want to be, the question left hanging in the air is ‘how are you going to get there?’ and it’s a question that every team wishes that you and your employer would agree upon. Most teams falter because leaders have failed to organize the workplace. This prevents team members from working productively with others, and from succeeding as individuals. Your team wants clear goals to work towards so that they can realize their own ambition: to be great at what they do. Head Techs without headaches are ones that have sat down with their employer and thought through a short list of what needs to be done in the practice in order to move the entire business towards the mission statement. It requires time for everyone to communicate thoughtfully and consistently. Communication is a word tossed about more frequently than the term mission statement, yet it too is never given the kind of consideration it genuinely deserves. In reality, most of us are poor communicators because we assume that if words come of our mouths in a grammatical manner that others will understand our meaning, but this isn’t true. In order for concepts to be understood, you often have to articulate them many times over, in many ways, and you should always be open to the idea that you still may not have made yourself clear. You and your employer should regularly discuss the mission and how it is expressed in the day-to-day actions of your practice. You should talk about goals, plan together, build action steps, and discuss your progress. If you want to take the icepack off that head and achieve success as a head tech, discuss goals for the practice with the other leaders in the building and agree on how they are to be achieved.

Time heals everything, including the head tech headaches If you are a head tech with a hurting head, you might blame the lack of time given to you to do the work of leadership. We’re very big on multitasking in veterinary medicine and expect all employees, not just head techs, to keep a few projects on the back burner as a way to justify payroll when the appointment book is looking light. However, great or even good leadership is not something that can be done on the fly. In order to be successful in your role, you have to take thoughtful time to think through how you will lead your team to working upon and achieving practice goals. And with that comes a responsibility on your part to want to succeed as a leader. Many head techs are stuck with the position, not desiring of it. If you are a leader that lacks passion for the position, both you and your employer should put together a strategy to move you into another role. Because you have no fire inside of you for the position itself, you have no fire underneath you to get its work done.

Action steps Eager head techs, having met with the other leaders of the practice and in agreement on what the practice’s goals are, should return to their technical teams with the goals themselves and an idea of how they can be achieved. You can out orders at this meeting and 912

make it clear how and when you’d like things done, but if you do, that headache you were worried about may set in again rather quickly. Instead, present the goals to the group and encourage a discussion on the topic as way to engage everyone or even as a way to discover why such goals may have failed in the past. Taking time to hear everyone’s concerns (and occasional digressions) can be tedious, but discussion is an essential part of the thought process and another important component of communication. It’s also demonstrative of the leadership’s respect for the input of the rank and file. Remember that meetings don’t have to be one-hour long. With the right kind of agenda and stewardship, groups can be taken through a discussion on a topic and come to a resolution on the matter in 30 minutes or less. Short, fast-paced meetings don’t have to mean that a topic is shortchanged. Provided the leader of the group is focused, shorter meetings can energize the group and consequently stimulate thought. They wake up team members and let them know that this isn’t a time for pizza and repose, but active, energetic, invested problem solving.

Leadership training As Robert Burns opined, ‘the best laid plans of mice and men often go awry’. Even if your practice owner, the other leaders, and you do your very best to get your hospital team focused upon and achieving goals, you will invariably encounter problems. In these moments, everyone will be tested to communicate (there’s that word again), remain patient, stay respectful, and work through problems constructively. In such meetings, you’ll have to practice negotiation and learn how to add input without offending or demoralizing. You’ll have to try to stay positive and professional, despite the real feelings of defeat, frustration, or fear that may be churning inside of you. Good leaders don’t have to like conflict; in fact, it’s helpful if they despise it. They don’t have to be bossy or extroverted or male or tall or most senior. They have to be focused on the goal and they have to inspire others to pursue it with the same passion that drives them and the other leaders of the practice. Leadership is not a set of must-dos as much as it is a combination of natural talent and the willingness to regularly review the impact and efficacy of one’s actions. In most cases, employees fail to live up to expectations for logical reasons. Rarely is their uninspired action or lack of action direct insubordination. Good leaders ask questions, listen to answers, and then formulate plans for everyone to move together successfully. Then, if that fails, they try again, and again and so forth until the practice steps forward or until it is clear that the best solution is to end the relationship entirely. Consequences for not living up to the practice’s Mission Statement, and everything for which it stands (the practice’s goals), must be as ultimate as the Mission itself. If you have a team member who has repeatedly failed to live up to the practice’s expectations and demonstrates an unwillingness to try to change, it’s the leader’s job to terminate the employee. Any member of the team, who insists on putting their own interests before the interests of the practice, is a blight on the practice and the rest of your employees. Shirking your responsibility to address such an employee is probably one of the biggest mistakes you can make and one of the chief reasons why so many head techs’ heads hurt. If you have an employer who refuses to back you up when taking a stand against willfully toxic and/or uncooperative employees, try engaging him or her in a discussion about the wisdom of their inaction. Even the most short-staffed practice owner is likely to admit that having one bad apple in the barrel risks spoiling a good deal of the others if not the entire stock. Once you agree on this matter, you will be able to formulate a plan for how to change the status quo.

Other resources Remember that the best way to cure your head tech headache is to nurse yourself. Invariably failure to succeed at leading has something, if not everything, to do with the leader herself. Regularly challenge your leadership actions and ask for feedback from your employees and employer. Review the reams of information available to you on the topic of leadership on the dvm360 website or explore membership in such organizations as VHMA and AAHA. Push yourself to understand why your head hurts and go to work immediately on one of the big reasons that’s probably responsible for the pain: you. Learning to be a better leader is not something you should eschew, rather understand that growing in your leadership capabilities means growing as an individual and becoming a valuable asset to your company, your family, your community, and this world.

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Cytology for Technicians Allison Kirby, DVM, DACVD Animal Dermatology Clinic Marina Del Rey, CA

Cytology key facts 1. One of the most valuable tools in Veterinary Dermatology. 2. Immediate information on presence of infectious organisms (cocci, rods, yeast, fungal spores) and different cell type (mast cells, neutrophils, macrophages) 3. As with everything practice is the key. When first starting to learn try to look at as many areas of the body as possible for normal and abnormal patients. One will not be able to determine abnormal if unable to determine what is normal. Equipment 1. Tends to be very low overhead 2. Microscope a. Ideal to have a 4X, 10X, 40X, and 100X objective b. Best to know how to Kohler Illuminate i. Good tutorial can be found at www.youtube.com ii. Search under Kohler illumination iii. Keep the light condenser up when examining a cytology sample and down when examining skin scraping/trichogram-increases contrasts to better identify parasites and hyphae c. Usually keep the light source dimmed when not in use so as not to burn out the bulbs as fast 3. Microscope slides a. I generally prefer the frosted slides for numerous reasons. i. They can be written on ii. I use the frosted edge as my focal point so I know what part of the body a sample was taken from iii. So you heat fix/and dry the appropriate side 4. Staining station a. Modified Wright’s stain like Diff Quik is generally what we use b. There is a Romanovsky-type stain but this gives less nuclear detail c. All stains should be changed at least weekly and containers cleaned d. Cytology of skin and ears should be separated from fecal slides 5. Cotton-tipped applicators a. Important for ear cytology b. Also can break the cotton swab in half and collect samples from claw fold 6. Clear Acetate Tape a. Especially useful on hard to sample areas (interdigital webbing), aggressive animals or very dry samples. b. Generally you can just dip the tape directly in the Dif Quik third solution and then examine 7. Spatula 8. Blades for deep and superficial scrapings 9. Oil Immersion a. Generally our clinics use Either A or B (difference is the viscosities level). Type A is less messy and less expensive 10. Cover slips a. Needed for New Methylene Blue (fungal slides) b. I generally don't use for anything else c. Some people prefer for skin scrapings 11. Lighter, coffee warmer, hair dryer (heat source), oil lamp a. Controversial b. idea is that it fixes waxy samples to the slide so sample is not lost during staining process c. If using a lighter or match there will be black char that develops on the bottom and will need to be wiped off.

Sampling technique 1. Many different ways to obtain samples and it depends on your comfort level 2. Ears: a. One cotton tip applicator per ear inserted into the vertical ear canal. 914

b. Roll the sample then onto the slide i. I generally put the left ear on the left side of the slide or the frosted edge of the slide ii. I place the right side on the side of the slide (away from the frosted edge) 3. Claw folds: a. Either a cotton tip applicator (broken in half) or the spatula/edge of the slide scraped parallel to the claw fold and then rolled/pressed onto a slide 4. Body Folds a. A cotton tipped pressed into the fold b. Then the sample rolled on the slide 5. Pustules, crusts, moist/greasy lesions a. Directly press the slides up against lesion in a single motion b. Crusts: Best to sample the area underneath the crusts c. For pustules and papules best to "pop" the lesion with a 25-gauge needle then press the slide on the ruptured lesion. 6. Dry/Scaly lesions/Difficult to reach areas (interdigital) a. Clear acetate tape is best

Examining the sample 1. Always examine at 4X first to find out where you should go down to higher power 2. Focus down on the areas with most amount of nuclear stranding and inflammation seen. a. Intracellular organisms=pathogenic= true infection. b. Organisms without the presence of inflammation is more indicative of either non-pathogenic bacteria, bacterial overgrowth or failure to select the infected area for sampling. 3. Be sure to always manipulate the fine focus to be able to differentiate between melanin granules and bacteria

Sample interpretation Infectious organisms Yeast 1. The most common yeast organism found on samples from dogs and cats is Malassezia pachydermatis, a. Classic “foot print” or "peanut" shape of a budding yeast organism. b. 3-5 µm in diameter c. Yeast organisms are usually found adherent to corneocytes. Bacteria 1. Staphylococcus Pseudointermedius a. infection is the most common bacteria isolated from infections of the ears and skin of dogs and cats b. Coccoid bacterium, 0.5-1.5 µm in diameter and is often found in pairs. 2. Pseudomonas aeruginosa a. Rod-shaped organisms, approximately 0.3-0.8 microns wide by 1.0-1.2 microns long b. Short chains. 3. Simonsiella spp. a. Harmless very large filamentous gram-negative saprophytes b. Inhabit the oral cavity of a variety of warm-blooded vertebrates 6-8 µm long and 2-3 µm wide. c. Presence is likely associated with licking Fungal spores 1. Demonstrated with either exfoliative or aspiration cytology. 2. Dermatophyte spores often appear as round spheres, usually about twice the size of coccoid bacteria 3. 3) Surrounded by a capsule that limits staining and gives "halo" appearance of a clear halo. Fungal hyphae 1. Uniform 2-3 µm wide filamentous structures often with poor staining characteristics Parasites 1. Cytology does not tend to pick up these organisms but can be picked up on scrapes 2. best under 4X power 3. demodex, sarcoptes and notoedres

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Documenting findings 1. Ensure you are giving the doctor an accurate picture of the slide. Standardize this interpretation of the slide so there is no confusion on severity of the condition.

Cells Degenerative neutrophils 1. With cocci= pyoderma Intact Neutrophils: 1. Sterile process like PF Eosinophils 1. Inflammation secondary to parasites 2. Hypersensitivity reactions such as (food allergies or atopy) 3. Pemphigus foliaceus 4. Foreign body reaction (such as free keratin within the dermis), 5. Ear cytology with topical reactions Mononuclear macrophages 1. Chronic or deeper lesions 2. 2) Phagocytic cells and often contain effete neutrophils, red blood cells, bacteria, fungal elements 3. Depending on the severity of the wound or lesion contamination, macrophages will often be markedly vacuolated and degenerate. Epithelial cells 1. Epithelial cells encountered normally on exfoliative cytology are corneocytes (non-nucleated keratinocytes) 2. Nucleated keratinocytes are normally found in samples from mucous membranes and associated with abnormal turnover of the layers of the skin Acantholytic cells 1. lower layer keratinocytes that have lost their adhesion to neighboring keratinocytes 2. Found in pemphigus foliaceus lesions, 3. Large, round cells with a central nucleus 4. Stain with a dark blue periphery 5. Found in rafts and amount well preserved neutrophils and/or eosinophils

Artifacts and other findings Melanin granules 1. Can also be mistaken for rod-shaped bacteria 2. Found in and around keratinocytes 3. Refractory brown to black color and are very even in size. Pollen 1. Multiple shapes and sizes and is often confused for fungal elements. 2. Pollen tends to be dramatically geometric and is usually not present in large numbers

References 1. Miller WHJ, Griffin CE. Campbell KL Muller & Kirk's Small Animal Dermatology. 7th ed. St. Louis, Elsevier, 2013. 2. Baker R, Lumsden J, H. Color Atlas of Cytology of the Dog and Cat. St. Louis, MO, 2000. 3.Medleau L, Hnilica KA. Small Animal Dermatology: A Color Atlas and Therapeutic Guide. 2nd ed. St. Louis, MO: Saunders, 2006.

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Feisty Felines: Bringing Up the Behaviorally Challenging Kitten Gary Landsberg, DVM, BSc, DACVB, DECVB-CA North Toronto Veterinary Behaviour Specialty Clinic Thornhill, Canada

Veterinarians and staff should work as a team to introduce cat owners to the concepts of normal feline behavior, reward training, and establishing healthy social relationships. This can be complemented by handouts and a list of reading and DVD recommendations. In addition, the clinic website should be populated with links to guide owners to the sites you recommend. Cat owners given educational material are at reduced risk for relinquishment.1

Behavior problems in cats In a study of 1177 cats 55% of owners reported at least one problem they would want to improve with anxiety most common at 16.7% followed by scratching 16%, feeding problems 11%, aggression 11%, inappropriate urination and spraying 8%, and defecation in the home at 5.1%.2 In a recent study of 277 cats, 61% engaged in one of 6 behavior problems with aggression to owners at 36%, urine soiling 24%, intercat aggression 21%, aggression to visitors 14%, stool soiling 13% and aggression to outdoor cats,12%. Yet only 54% of owners reported these signs to their veterinarian and only about 25% of veterinarians ask.3,4 In a survey of over 1200 cats adopted from shelters, scratching, digging and chewing were reported in 25% of cases in the first week which increased to 28% after one month. Energy level increased (14% to 28%) as did biting and growling. Only shy, fearful and hiding reduced.5 Therefore behavior counseling of new cat owners is essential for problems to be improved and reduced.

Feline behavior and development Cats might be categorized as a) sociable, confident, and easy going or b) timid, nervous and aggressive. While genetics, especially paternal, has a strong influence this is modified by environment especially prenatal (including the health, nutrition and environment of the mother) and the early postnatal (including maternal effect, handling and socialization).6,7 Kittens separated from their mother and hand raised by 2 weeks of age are more fearful and aggressive toward people and cats, more sensitive to novel stimuli, learn more slowly, and develop poor social skills. Kittens receiving early gentle handling by humans develop healthier social relationships, have accelerated development and are less fearful.

Preventive counselling Educating new kitten owners on normal behavior, cat communication and body language, socialization, reward based training and enrichment can help to prevent undesirable behaviors. When introducing a new cat the use of pheromones (Feliway) might lessen the stress (improve appetite, less marking). The new cat should be given its own safe, enriched housing area, and introduced gradually to other pets and the rest of the home while insuring positive outcomes. Feliway muli-cat might be more appropriate for multi-cat homes. In a recent study a significantly higher percentage of owners that received no counseling sought advice (46% vs. 4%) or reported behavior issues 10 months later compared to those that had counseling visit of 25 minutes with a veterinary behaviorist at 2-4 months of age. Control cats had more vocalization and climbing problems (furniture, curtains), were more noise sensitive and more likely to solicit attention when the owner was resting. Cats in the treatment group were more likely to greet on homecoming and less likely to react negatively to body handling.8 Socialization and encouraging positive outcomes Since the upper end of the sensitive period is 7 to 9 weeks, every effort should be made to socialize prior to this age. Treats and toys can be used to make social interactions, handling and stimulus exposure positive. Learning should be reward based to increase behaviors that are desirable. can be particularly useful for immediate timing of rewards. Punishment should be avoided as it leads to fear and avoidance. Environmental enrichment All animals require an environment that is physically and mentally stimulating and that meets their behavioral needs. Animals kept in a restricted environment may not have adequate opportunity to engage in their full behavior repertoire. The indoor feline environment should therefore provide for food, water, elimination (litter), scratching, elevated perches, comfort and security and opportunities for enrichment including social and object play, exploration and reward training. When sufficient outlets are not available, the pet may engage in behaviors that are undesirable to the owners or develop stress induced health and behavior issues. Many common behavior concerns including scratching, over-exuberant play, chasing, climbing, attention seeking, nocturnal behavior, soiling and vocalization, can be prevented, managed, or resolved by providing appropriate outlets.  Social time with owners and other cats plays an important role in enrichment and in maintaining healthy social relationships. Prey type toys attached to a wand or rope can be dangled and moved to stimulate hunting which might normally occur as many as 40 times or more a day.

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 Reward train what you want the kitten to learn. When giving toys, treats or catnip reward and train what is desirable and associate words to cue the interactions (communicate).  Feeding toys and object play: In nature cats hunt, capture, and kill multiple prey a day. As an alternative to hunting, cat owners can offer multiple small meals in toys that require rolling, batting, chasing, pawing or chewing to release food. Food can also be scattered or hidden to encourage exploration.  Outlets for scratching, climbing and perching should also be provided.  Outdoor access: While outdoor access may be undesirable or impractical for some homes, training the cat to be comfortable on a leash and harness or the use of cat proof enclosures can provide a practical and safe option for outdoor enrichment. Elimination Since cats generally prefer to eliminate in a substrate in which they can scratch and dig, an indoor box with commercial litter is usually effective. Litter type, number, size, type and location of boxes, and adequated cleaning are needed to establish regular litter box use. Management and safety Strategies may also be needed to prevent access to areas where problems might arise by cat proofing, blocking off areas or confinement training. The use if an unpleasant substrate such as an aluminum pan with water, sticky tape or carpet runner with nubs can be used to deter use of areas. . Comfort and privacy Cats should be provided with opportunities to perch, rest, sleep and hide, and sufficient space to be able to allow them make choices when and where they want privacy. A normal feline time budget might allocate 44% to sleep, 22% rest and 15% grooming.9. Neutering Androgen influenced behaviors can be reduced or eliminated by neutering. Kitten kindergarten Kitten classes are valuable for socializing kittens, exposing them to a variety of novel stimuli, and teaching good manners. Offering these classes in a veterinary clinic help the kittens (and owners) develop positive associations with the veterinary clinic and staff. Topics include positive body handling, reward training, litter box management, enrichment, adminstering medication, handling, harness and , the perils of punishment, and sessions to socialize and play.

The feisty feline Scratching Scratching serves a variety of purposes including marking, nail maintenance, and stretching after rest and may increase in response to stress. Owners should provide a scratching post at or near the cats preferred scratching location with a substrate and structure that is appealing, ideally one that is similar to what the cat is presently targeting. Placing catnip, or treats in the area, rewarding / clicker training and the use of feline interdigial pheromone (available in Europe) will encourage the use of the post. In a recent study of over 4000 cats, cats that were rewarded were more likely to use the preferred post and punishment did not affect frequency of inappropriate scratching.10 While carpet was the most frequently offered substrate, rope (sisal) was used most often (33%) followed by carpet (25%) and cardboard (18%). Cats over 10 preferred carpet (25%), rope (23%) and cardboard (20%).10 Most cats 9 or less preferred cat trees with multiple levels (76%) followed by vertical posts (69%), horizontal (50%) and hung on the wall 6%). Cats preferred posts that were narrower < 3 feet, and shorter <3 feet.10 Inappropriate scratching was reported by 52% of owners, 65% at least once a day and 35% multiple times daily and was unrelated to number of cats or sexual status. Cats obtained from breeders had least inappropriate scratching (38%) and those from shelters most (54%). Inappropriate scratching was associated least with rope covered posts. Cat trees with two or more levels were associated with least inappropriate scratching (55%) with those hung on the door associated with most inappropriate scratching (74%). Inappropriate scratching was less with posts >3 feet (55%) compared to smaller posts (65%). Of cats that were declawed 8.5% were in the front and .9% front and rear, primarily to prevent damage (44%), followed by injury to people (18%) and injury to other pets (11%). Twenty nine percent of cat were declawed when obtained.10 Cats that continue to scratch inappropriate targets in response to stress might benefit from applying Feliway to these areas. To prevent further scratching at a site, the scratching post might be placed directly in front of the area, access to the area can be blocked, the cat confined away from the site, or environmental deterrents used. Outdoor access may reduce indoor scratching but there is no evidence that it improves inappropriate scratching.10 Play / predation When aggressive play is directed at the owner, the primary focus should be to redirect the predatory play to appropriate outlets such as toys attached to ropes or wands or that can be tossed to stimulate chasing, pouncing and biting at times of day when the behaviors are most likely to arise. When hunting, cats engage in multiple short bouts of chase, may have a daily catch of 8-10 mice, with excursions lasting up to 30 minutes.11 A cat may spend 14% of its day hunting, 3% traveling and 2% feeding.9 Therefore it is not surprising that

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some cats, will engage in multiple stalk, chase and bite sessions toward owners and other cats. However, perhaps surprisingly in one study cats that hunted and those that spent more time outdoors were reported to have more behavior problems.3 Play with toys can provide an alternative outlet for hunting behavior as well as an opportunity for social interaction and training. Toys with play like characteristics (size, movement, odor) will solicit play.11 However after two to three bouts of chase with a specfic toy, the cat may lose interest but remain in a heightened state of arousal. Within 5 minutes play with a novel toy was disinhbitied and more intense with 25 to 45 minutes needed till intensity is reduced.11 Therefore at least one or two additional toys should be offered for novelty, and the cat offered an alternative activity such as a food filled or catnip toy or a small meal to keep it focused, allow the cat to settle and perhaps simulate prey capture. In one study owners that played with their cat in more than 5 minute bouts a day had fewer problems.3 Owners should diarize when play attacks arise so that they might schedule pre-emptive play or confine the cat with alternative forms of enrichment (e.g. food filled toys, cardboard box to explore). Since satiation reduces the motivation to hunt and play, feeding multiple small meals might also reduce play predation.12 Training the cat to engage in desirable behaviors on cue (e.g. sit, go to your mat) provides the owners with a communication tool to direct the cat into alternative acceptable behaviors if the owners can identify the body language of impending attack. If signs and situations for aggression are recognized the owner can throw treats to redirect and countercondition the cat. Leaving a bell attached or a leash and harness to inhibit and redirect the cat might also be helpful. While getting a second “compatable” cat could result in new issues, it can be an effective solution for some cases.

Social relationships When adopting a new cat, it should be confined to its own enriched housing area within the home, so that it might be gradually introduced to other cats, people and increasingly more of the home while insuring positive outcomes. Over time, some cats develop strong bonds with other cats, while some require very gradual introduction and an ongoing need for space, privacy and restricted interactions.

Petting aggression This aggression may be inhibited or intense. What is most confusing to some owners is that the sequence may begin with the cat seeking physical contact. However, after a variable period of time, the cat may become agitated and bite. This may be related to the cat’s level of arousal, previous unpleasant experiences with handling and restraint or even a sensitivity to touch. Owners must learn to recognize feline body language to identify the earliest signs of anxiety, as well as when and where problems might arise and the type and length of petting the cat will tolerate. While recognizing and respecting the cats limits, giving rewards during petting and ceasing before any signs of anxiety can gradually countercondition a longer response.

Summary Understanding normal feline behavior and development is necessary to adequately meet the kittens needs Many of the most common undesirable behaviors in cats can be effectively addressed by understanding and meeting these needs. Preventive counseling is effective in preventing many of the common feline undesirable behaviors. Therefore, veterinarians and staff should be proactive in providing behavior advice and resources for client education

Web resources Ohio State University: environmental enrichment www.indoorpet.osu.edu, https://indoorpet.osu.edu/sites/indoorpet/files/assets/documents/KeepingCatsIndoors-2013.pdf American Veterinary Society of Animal Behavior: www.catvets.com International Society of Feline Medicine: www.icatcare.org Catalyst Council: catalystcouncil.org AAFP and ISFM feline environmental needs guidelines: http://bit.ly/14uWTCB.

References / suggested reading 1. Patronek GJ, Glickman LT, Beck AM et al Risk factors for relinquishment of cats to an animal shelter. J Am Vet Med Assoc 1996; 209; 572–581 2. Heidenberger E. Housing conditionis and behavioral problems of indoor cats as assessed by their owners. Appl Anim Behav Sci 1997; 52: 345-364. 3. Strickler BL, Shull EA. An owner survey of toys, activity problems and behavior problems in indoor cats. J Vet Behav 2014; 9, 207-214 4. Hetts S, Heinke ML, Estep DQ. Behavior wellness concepts for general practice. J Am Vet Med Assoc 2004, 225, 506-513 5. Lord LK, Reider L, Herron ME, et al. Health and behavior problems in dogs and cats one week and one month after adoption from animal shelters. J Am Vet Med Assoc 2008; 233, 1715-1722 6. Lowe SE, Bradshaw JW. Ontogeny of individuality in the domestic cat in the home environment. Anim Behav 2001; 61; 231 7. McCune S. The impact of paternity and early socialisation on the development of cats’ behaviour to people and novel objects. Appl Anim Behav Sci 1995; 45; 109 8. Gazzano A, Bianchi L, Sonia C et al. The prevention of undesirable behavior in cats; effectiveness of veterinary behaviorists’ advice given to kitten owners. J Vet Behav 2015; in press, DOI: 10.1016/j.jveb.2015.07.042 919

9. Panaman R. Behavior and ecology of free-ranging female farm cats. Z Tierpschol 1981; 56; 59-73 10. Wilson C, Bain M, DePorter T, et al. Owner observations regarding cat scratching behavior: an internet-based survey. J Fel Med Surg 2015; in press, DOI: 10.1177/1098612X15594414 11. Hall SL, Bradshaw JWS, Robinson IH. Object play in adult domestic cats: the roles of habituation and disinhibition. Appl Anim Behav Sci, 2002; 79; 263-271 12. Hall SL, Bradshaw JWS. The influence of hunger on object play by adult domestic cats. Appl Anim Behav Sci 1998; 58; 143-150

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Common Emergency Procedures You Must Know Justine Lee, DVM, DACVECC, DABT VETgirl, LLC Saint Paul, MN

Veterinary technicians are vital in performing and assisting with common emergency room procedures. Veterinary technicians should feel comfortable obtaining intravenous (IV) access (e.g., peripheral or central catheter placement, jugular cutdown), placing nasoesophageal (NE) or nasogastric (NG) tubes, placing nasal oxygen, performing nebulization and coupage on dyspneic patients, and tube feeding neonates. Likewise, veterinary technicians should feel comfortable assisting veterinarians with more advanced emergency room procedures such as thoracocentesis and decontamination of the poisoned patient (e.g., emesis induction, administration of activated charcoal, gastric lavage).

Venous access The use of indwelling IV catheters is commonly used in veterinary medicine. These can be placed in either peripheral (e.g., cephalic, lateral saphenous) or central (e.g., jugular, medial saphenous) locations Peripheral catheter placement can typically be performed with minimal physical restraint. For central catheter placement, light sedation is recommended. Regardless, aseptic technique should be used for indwelling catheters; with sterile technique, venous access can be maintained for days. Indwelling catheters can be used for: 1. Fluid therapy administration 2. Drug administration 3. Blood transfusion product administration 4. Measurement of central venous pressure (CVP) - central 5. Administration of drugs that are perivascularly irritating - central 6. Hyperosmotic fluid administration (e.g., total parenteral nutrition, > 5% dextrose solutions, etc.) - central 7. Venous access for blood draws and clinicopathologic testing - central For a step-by-step approach on IV catheter placement, the reader is referred to:[1] http://www.cliniciansbrief.com/sites/default/files/sites/cliniciansbrief.com/files/patientsupport_aug06.pdf

Nasoesophageal and nasogastric tube placement Placement of NE or NG tubes are commonly performed in the emergent or critically ill patient. These temporary feeding tubes can be beneficial as they can allow for the following:  Emptying of gastric residual volume  Administration of a liquid enteral diet (e.g., Clinicare)  Trickle feeding post-operatively to stimulate enterocyte health and gastrointestinal motility  Administration of liquid medications (e.g., antibiotics, antacids, anti-ulcer medication, etc.)  Administration of oral water to aid in hydration of the patient (particularly in patients with heart disease who are at risk for volume overload). In order to perform NE or NG tube placement, the following steps should be followed: 1. Organize all your supplies so they are readily available in an organized fashion (feeding tube, suture, 20-gauge needle, proparacaine, e-collar, empty syringe, sterile water). 2. Apply 1-2 drops of proparacaine into the designated nostril. 3. Pre-measure the designated feeding tube from the last rib of the patient to the nostril. 4. Mark the line with a permanent marker. 5. Use sterile lubrication to lightly lubricate the tip of the NE tube. 6. Have someone firmly restrain while you, with intentional, rapid, short, fast motions, insert the nasoesophageal (NE) tube into the nostril, directing it ventromedial. 7. Insert in as rapidly as possible to the pre-marked line. 8. Using a 20 gauge needle, make a pinch bite at the lateral nares, avoiding the eye. 9. Feed suture material in through the needle tip, and extend it fully through the hub. Rapidly remove the needle, and suture a Chinese finger trap around the NE tube. Repeat this at the lateral zygomatic arch (avoiding the eye) and tie another suture into this area to secure the NE tube. 10. Apply an Elizabethan-collar on the patient immediately. 11. Aspirate the NE tube – you should get negative pressure. If you do not, you may be in the trachea. Caution should be used, as negative pressure does not definitive indicate that you are in the esophagus (you could be lodged up against the end of a bronchus). REMINDER: There usually isn’t any gas in the esophagus (think chest radiographs)!

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12. Using a 20 mls syringe filled with air, rapidly bolus in the air into the NE tube while simultaneously ausculting over the stomach (right sided). You should auscult for “gurgling” of the stomach simultaneously. 13. Verify by administering 5 mls of sterile water into the NE tube – any dyspnea, coughing, or tachypneic should prompt immediate radiographs or removal of the tube. 14. Always verify the placement of a tube by performing a lateral radiograph, which should including the neck. Verify that the tube is in the esophagus, ideally sitting just caudal to the cardiac silhouette. When in doubt, repeat or add contrast to verify placement. 15. Calculate resting energy requirements and feed accordingly [2]. 16. Appropriately mark the NE or NG tube with white tape that states “NG/NE” so it is not confused with a nasal oxygen cannula.

Nasal oxygen cannulas The use of nasal oxygen cannulas can be easily placed in the medium to large sized dog. The author does not recommend placement of nasal oxygen cannula in cats, as they are obligate nasal breathers. Note that small dogs and cats can be easily treated in an oxygen cage, while larger dogs cannot fit in many oxygen cages. As a result, the use of nasal oxygen cannulas can help provide oxygen supplementation. The benefit of intranasal oxygen therapy is that it is generally well tolerated, provides excellent patient accessibility (e.g., the patient isn’t “locked” in an oxygen cage), and can deliver a fraction of inspired oxygen (FiO2) of 40-60% (at 50-100 ml/kg of oxygen). In order to place a nasal oxygen cannula, the following steps should be followed: 1. Organize all your supplies so they are readily available in an organized fashion (red rubber catheter, suture, 20-gauge needle, proparacaine, e-collar, oxygen tubing). 2. Apply 1-2 drops of proparacaine into the designated nostril. 3. Pre-measure the red rubber catheter to the media cantus of the eye. 4. Mark the line with a permanent marker. 5. Use sterile lubrication to lightly lubricate the tip of the red rubber catheter 6. Have someone firmly restrain while you, with intentional, rapid, short, fast motions, insert the red rubber catheter into the nostril, directing it ventromedial. 7. Insert in as rapidly as possible to the pre-marked line. 8. Using a 20-gauge needle, make a pinch bite at the lateral nares, avoiding the eye. 9. Feed suture material in through the needle tip, and extend it fully through the hub. Rapidly remove the needle, and suture a Chinese finger trap around the red rubber catheter. 10. Apply an Elizabethan-collar on the patient immediately. 11. A Christmas tree adaptor often needs to be used on the end of the red rubber catheter to connect to the oxygen tubing. 12. Appropriately mark the red rubber catheter with white tape that states “O2” so it is not confused with an NE or NG tube.

Performing nebulization and coupage The use of nebulization and coupage is important in the critically ill patient. Nebulization provides a fine mist of liquid droplets as part of aerosol therapy and aids in humidifying pulmonary secretions, stimulating coughing, loosening secretions, and enhancing clearance by the mucociliary escalator (so pulmonary secretions can be expectorated out).[3] Nebulization is indicated for upper respiratory conditions such as pneumonia, upper respiratory infections, tracheobronchitis, etc.) and as part of tracheostomy care [4]. Coupage, rotation of the patient, and limited exercise (e.g., encouraging walking) can help enhance expectoration and mobilize airway secretions. The use of nebulization and coupage should ideally be performed every 4-6 hours in the pneumonia patient.

Tube feeding neonates Neonates often present to the emergency room for “failure to thrive.” Once the neonate has been stabilized (e.g., hydrated, euglycemic, normothermic, etc.), oral-gastric feeding should be implemented. A 5 or 8 French pre-measured red rubber feeding tube can be used. To perform this, measure from the tip of the nose to the last rib; mark the tube with a small piece of white tape (as this will be the maximum distance to pass the tube). The tube should be passed down the left side of the mouth; note, a gag reflex may not be present until 10 days of age.[5] Ideally, the appropriate species milk replacer should be given. The use of oral water or dextrose can also be given via the feeding tube if needed. The fluid should be warmed to near body temperature prior to administration, and administered slowly over several minutes.[5] After delivery of fluid, the tube should be kinked prior to withdraw to prevent secondary aspiration pneumonia. This is a procedure that is easy to perform; pet owners can also be taught to perform this for unique situations [e.g., if nursing off the mother is contraindicated (e.g., eclampsia, rejection), if the neonate has a weak suckle, with a severe cleft palate, etc.]. NOTE: The normal stomach volume of the neonate is estimated to be 50 ml/kg; the patient should be fed every 2-4 hours and overfeeding should be avoided [5]. 922

Performing a thoracocentesis in dogs & cats A thoracocentesis is often life-saving, and should be performed immediately in any dyspneic patient that is suspected of having pleural effusion. The thoracocentesis should be performed cranial to the rib, as the blood vessels and nerves lie caudal to the rib (“hiding” behind the rib). Thoracocentesis should be performed at the 7-9 intercostal space (ICS) to avoid the heart (3-5 ICS) or liver (caudal to the ninth ICS). The patient should be shaved, scrubbed, and prepared for sterile technique. The use of a 3-way stopcock, extension tubing, an appropriately sized needle or catheter, and syringe should be used to collect air or fluid. Appropriate sterile collection tubes should be available for sample collection for cytology and/or culture purposes.

Inducing emesis in the poisoned patient Emetic agents work by causing local gastric irritation, stimulating the central nervous system (CNS) chemoreceptor trigger zone (CRTZ), or a combination of gastric irritation and CNS stimulation.[6,7] Emetic agents are not effective if an antiemetic such as ondansetron or maropitant has been previously administered. Currently, the only home recommendation for dog owners is hydrogen peroxide, while veterinary-prescribed emetic agents include apomorphine hydrochloride (dog) and dexmedetomidine (cat) or xylazine hydrochloride (cat).[6,7] In the dog, hydrogen peroxide works by local irritation of the oropharynx and gastric lining, which results in a gag reflex. It is usually recommended for oral administration by the dog owner when transportation to a veterinary clinic is delayed. Only a 3% hydrogen peroxide solution should be used, as higher concentrations can potentially be corrosive to the GI mucosa. Adverse effects associated with use of hydrogen peroxide as an emetic agent include irritation to the GI tract, gastric dilatation and/or volvulus (dogs), and potential for aspiration pneumonia.[6,7] Hydrogen peroxide is not a reliable emetic in cats and its use generally is NOT recommended in this species. In addition, cats can develop profound clinical signs from the administration of hydrogen peroxide including profuse foaming from the mouth and severe hemorrhagic gastritis. Apomorphine hydrochloride is a centrally acting emetic agent that is highly effective in dogs. Administration results in stimulation of the CRTZ, quickly followed by emesis. Adverse effects associated with apomorphine administration are prolonged emesis and ocular irritation when administered subconjunctivally.[6,7] Apomorphine should not be used in cats, as it is not considered to be effective. Apomorphine should not be used when there has been ingestion of medications that result in compounding of symptoms (e.g., respiratory or CNS depression) or with antidopaminergic drugs (e.g., metoclopramide) that prevent emesis from occurring. Dexmedetomidine and xylazine hydrochloride, alpha adrenergic agonists, are centrally-acting emetic agents that are used as emetic agents in cats. The use of apomorphine and hydrogen peroxide are not recommended for cats, as they are ineffective or can result in severe adverse effects (e.g., hemorrhagic gastritis), respectively. Xylazine does not reliably produce an emetic response in dogs, and thus is not recommended in dogs as an emetic agent. Adverse effects associated with alpha-adrenergic drugs include bradycardia, sedation, tremors, and respiratory depression.[6,7] Thawley and Drobatz found that dexmedetomidine resulted in emesis approximately 80% of the time in cats, as compared to only about 44% of the time in cats with xylazine.[8] Alpha adrenergic agonists should not be used in cats that have ingested medications (e.g., other alpha-adrenergic agonist drugs) or products that may result in compounding of bradycardia, respiratory depression, sedation, or CNS depression symptoms.[6,7] Methods that are not recommended for emesis induction include digital induction of emesis, syrup of ipecac, liquid soaps, dry mustard powders, and salt. Digital induction of emesis often results in physical injury to the pet owner (), or injury to the pet’s throat and soft palate. Syrup of ipecac has historically been recommended to induce emesis, but is no longer the standard of care. Its cardiotoxic potential and tendency to result in prolonged vomiting, lethargy, and diarrhea have caused it to fall out of favor in both human and veterinary medicine.[6,7] Soaps, mustard powders, and table salt are not reliable as induction agents and may be detrimental (e.g., resulting in further complications such as hypernatremia of the patient).

Performing gastric lavage for poisonings Gastric lavage is a labor-intensive procedure, but is life-saving with certain toxicants. While emesis induction can be safely performed in the majority of poisoned patients (e.g., in asymptomatic patients, with recent ingestion within the past 1-2 hours, etc.), some toxicities warrant the use of gastric lavage. These are typically deadly ingestions such as:  Organophosphates/carbamates  Cholecalciferol (found in rodenticides, psoriasis creams, and )  Baclofen (a centrally acting muscle relaxant)  Macrocyclic lactones (e.g., ivermectin, moxidectin)  Deadly medications (e.g., calcium channel blockers, 5-FU, etc.)  Any dose that is approaching the LD50 of the drug The goal of gastric lavage is to remove gastric contents when emesis induction is unproductive or contraindicated. For example, an obtunded, comatosed patient presenting with baclofen toxicosis is at high risk for aspiration pneumonia if emesis induction is performed. In this situation, protecting the airway with an inflated endotracheal tube (ETT) and gastric lavage is safer. Rarely, complications of gastric lavage may occur, and include risks of sedation, secondary aspiration pneumonia (once extubated), 923

mechanical injury (to the mouth, oropharynx, esophagus, stomach), or respiratory effects (e.g., hypoxemia secondary to aspiration, hypercapnea secondary to sedation, etc.).[5] Contraindications that exist for gastric lavage include[5]:  A corrosive agent, where esophagus or gastric perforation can occur with orogastric tube placement (e.g., drain cleaners, oven cleaners, ultra-bleach, batteries, etc.)  Petroleum distillates or hydrocarbons (e.g., gasoline, kerosene, motor oil), which may be easily aspirated due to its low viscosity.  Sharp objects ingested (e.g., sewing needles, knives, etc.)

Not knowing more about activated charcoal After an appropriate history, triage, physical exam, and initial decontamination procedures have been performed in the poisoned pet, the next step is the administration of activated charcoal (AC), if appropriate. Activated charcoal should not be given to the poisoned patient when the toxicant does not reliably bind to AC (see below) or when it is contraindicated to administer AC (e.g., salt toxicity, poor gag reflex).[5] In addition, symptomatic patients who are at risk for aspiration pneumonia should not be administered AC orally. Finally, the administration of AC with a cathartic should be cautiously used in dehydrated patients due to the potential (albeit rare) risks for hypernatremia secondary to free water loss in the GI tract.[5] When administering AC, it should ideally be given within < 5 minutes of ingestion to be most effective. In veterinary medicine, this is almost impossible due to driving time (to the clinic), lapsed time since ingestion, time to triage, and the amount of time it takes to physically deliver AC (e.g., syringe feeding, orogastric tube). As a result, administration of AC is often delayed for up to an hour or more. As time since ingestion is often unknown (e.g., pet owner coming home from work to find their pet poisoned), decontamination (including emesis and administration of AC) is often a relatively benign course of action, provided the patient is not already symptomatic. As always, when administering any drug, it is important that benefits outweigh the risks, and that complications be prevented when possible. In veterinary medicine, administration of AC with a cathartic as long as 6 hours out may still be beneficial with certain types of toxicosis, particularly if the product has delayed release [e.g., extended release (XR) or sustained release (SR)] or undergoes enterohepatic recirculation.[5, 6] While human medicine has moved away from administration of AC with poisoned patients, the aggressive use of AC in veterinary medicine is still warranted, as this is often our last line of defense when it comes to adequately decontaminating our patients. Certain modalities of therapy—e.g., antidotes [such as fomepizole, pralidoxime chloride (2- PAM), digoxin-specific antibody fragments], plasmapheresis, hemodialysis, mechanical ventilation— along with financial limitations of pet owners, limit our ability to treat poisoned pets aggressively as compared to human medicine. As a result, the continued use of AC in veterinary medicine is still warranted as a first line of defense therapy. Current recommended dosing for single dose AC is 1–5 g of AC/kg with a cathartic (e.g., sorbitol) to promote transit time through the GI tract.

Conclusion Veterinary technicians should feel comfortable performing or assisting in these common emergency room procedures, as they can be life-saving for the emergent or critically ill patient.

References 1. Weil AB, Ko J. Intravenous Indwelling Catheters: Use & Care. Clin Brief 2006:53-58. Accessed: http://www.cliniciansbrief.com/sites/default/files/sites/cliniciansbrief.com/files/patientsupport_aug06.pdf 2. Chan D. How I... Tube Feed Dogs and Cats. British Small Animal Veterinary Congress 2007, Proceedings. 3. Schulz HM, Rahilly LJ. Aspiration Pneumonia in Dogs: Treatment, Monitoring and Prognosis. Compendium: Cont Ed Vet 2012: E1-E5. 4. Jack CM, PM, Donovan MS. Veterinary Technician’s Daily Reference Guide: Canine and Feline, 2nd. ed. Blackwell Publishing, Ames: 2008. 5. Lee JA, Cohn LA. Pediatric Critical Care Part 2: Monitoring & Treatment. Clin Brief 2015;39-44. 6. Lee JA. Decontamination of the Poisoned Patient. In: Osweiler G, Hovda L, Brutlag A, Lee JA, ed. Blackwell’s Five-Minute Veterinary Consult Clinical Companion: Small Animal Toxicology, 1st Ed. Iowa City: Wiley-Blackwell, 2010, pp. 5-19. 7. Peterson ME. Toxicological Decontamination. In: Peterson ME, Talcott PA, ed. Small Animal Toxicology, 2nd Ed. St. Louis: Elsevier Saunders, 2006, pp. 127-141. 8. Thawley VJ, Drobatz KJ. Assessment of dexmedetomidine and other agents for emesis induction in cats: 43 cases (2009-2014). J Am Vet Med Assoc 2015;247(12):1415-1418.

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A Painless Career Choice: Careers for Technicians in Pain Management Tasha McNerney, BS, CVT, CVPP Veterinary Anesthesia Nerds Glenside, PA

Today technicians can pursue further training and specialization in many avenues including dentistry, anesthesia, internal medicine and emergency and critical care. The possibilities are seemingly endless for technicians who wish to further their education and expand the depth of their career. One such avenue for extra training and knowledge is in the field of pain management. This is an exciting new avenue for technicians (and veterinarians as well) to help strengthen not only the practices bond with the animal but the clients relationship as well. Pain management has become an important specialty area in human medicine and that has inevitably led to a greater awareness of pain in animal companions. Pet parents want the best for their furry family members and that includes top-of-the-line treatments for pain management. It was once thought that animals did not experience pain in the same way that humans do. But research supports that if a procedure is thought to be painful to us, it will also be painful to our fuzzy friends as well, even though they may go to great lengths to hide it from us. Therefore proper pain management must be offered to all patients. In addition to pain medications (analgesics), many clinics are now offering complementary treatments like physical rehabilitation, acupuncture and laser therapy to treat pet pain. In veterinary medicine we now know that pain is best managed through an interdisciplinary approach and that effective pain management can be best achieved through cooperation, sharing knowledge, and the collective wisdom of veterinary professionals from many disciplines. The International Veterinary Academy of Pain Management is the cornerstone of knowledge and advancement in the field of pet pain management. They currently execute a program for veterinary professionals to gain advancement in the field of pain management. The IVAPM’s current program will lead to the title of Certified Veterinary Pain Practitioner (CVPP) for veterinarians and licensed technicians; Certified Animal Pain Practitioner (CAPP) for physical therapists and physical therapist assistants with certification in canine rehabilitation. This is an exciting opportunity for veterinary technicians in particular. It is IVAPM’s strongly held view that the CVPP and CAPP recognition is well within the scope of any veterinary professional to attain, and the IVAPM encourages all to consider its merits and begin the application process. The certification program is intended to emphasize the value of the many disciplines capable of enhancing patient comfort and quality of life, and to facilitate an understanding of the modalities not necessarily in the technician’s current area of familiarity. These areas include:  Analgesic drug therapies  Analgesic adjunct therapies  Physical rehabilitation methods  Complimentary alternative therapies such as acupuncture and massage Obtaining the CVPP/CAPP provides the stage upon which all professionals committed to promoting, enhancing, and advancing pain management in animals may interface. It is the foundation upon which the veterinary profession can build the most effective multidisciplinary pain management team. By using a multimodal approach the CVPP can use analgesic drug therapies along with physical therapy techniques such as massage, hydrotherapy and acupuncture to create a multidimensional pain management plan to help the patient achieve the desired outcome After obtaining a CVPP, the veterinary technician can work together with pet owners and veterinarians to provide the best pain management plans for patients. CVPP’s can best be used in the following 3 ways: 1. The CVPP can assess the patient’s current status and pain management regime and together with the owner create a pain management plan specific to that patient for the best overall outcome. 2. CVPP’s can also help in the acute pain management setting helping clinics to create protocols for post-operative pain scoring and proper analgesic techniques for acute surgical pain. 3. The CVPP also acts as an important “point person” that the owner can contact and relay information about the pet’s progress. The CVPP can then use this information to make changes to the analgesic plan as necessary to ensure the best outcome for that patient. By obtaining your CVPP you can also help in the continuing education of your clients and staff. Many veterinary professionals who have obtained the CVPP designation go on to write magazine articles, teach online courses, and lead seminars on various pain management topics. There are so many opportunities for the veterinary technicians when it comes to pain management. Technicians can further their education and become certified in acupuncture, massage therapy, reiki and various other pain management modalities.

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By reaching the goals associated with a Certified Veterinary Pain Practitioner, veterinary technicians can increase patient safety and comfort, increase the overall morale at your practice, educate clients on the importance of proper pain management, and increase client compliance in this area. If you are a veterinary technician with an interest in pain management please consider the CVPP/CAPP path. If you have any questions about this process, please visit the IVAPM website at www.IVAPM.org or 615-301-3040 by phone.

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Critical Patient Pain Management Tasha McNerney, BS, CVT, CVPP Veterinary Anesthesia Nerds Glenside, PA

The role of veterinary technicians in developing an anesthetic and analgesic protocol for critical patients is a complex task. The veterinary technician must work together with the clinician and other team members to ensure that the critical patient is properly evaluated and cared for. Before administration of any anesthetic and analgesic agents, each patient must have a physical exam. This is exam should include ( but is not limited to) a chest auscultation to assess cardiovascular and respiratory function, an ECG, temperature, blood pressure, femoral pulse evaluation, and pulse oximetry readings. In some cases it is also important to obtain lab values such as a PCV/TS, blood glucose, electrolyte panel, creatinine level, and blood gases. Once the clinician develops a clearer picture of overall patient status, they can assign an ASA rating, and an anesthetic and analgesic protocol can be administered. Proper protocols will change with each patient and the type of surgery or treatment needed as well as perceived pain. It is important to note that if a patient is thought to be in pain, analgesics should NOT be withheld. This lecture will discuss four common critical patients that are often in need of anesthesia and analgesia.

The urethral obstruction patient Cats with urethral obstruction often present in pain and distress. They often require immediate and rapid urethral catheterization. Treatment should begin with assessing the patients’ electrolyte and hydration status and checking for any arrhythmias. Hyperkalemia is a common finding in urethral obstruction patients. This can lead to ECG changes such as a wide QRS complex and absent or flat P waves. Often the T wave is peaked or tented. (Fossum, 2007) Hyperkalemia and acidosis may require additional drug therapies such as calcium gluconate, insulin given with a concurrent dextrose drip, sodium bicarbonate (Perkowski, 2000) Although calcium gluconate does not alter potassium values, it does stabilize cell membranes, allowing time to reduce the potassium levels and minimize the cardio toxic effects of hyperkalemia. (Cummings, 2014) An IV catheter should be placed in all critical patients, especially the urethral obstruction patient. Cats will often need analgesics as well as sedation for placement of urinary catheter. Analgesia can be achieved with buprenorphine or hydromorphone. Propofol may be used as an induction agent prior to general anesthesia. Also, if the patient is in the early stages of the disease ketamine can be used in conjunction with diazepam for induction of general anesthesia. If the patient arrives laterally recumbent or critically ill, they may not require chemical restraint. In these patients, urethral catheterization can often be achieved with an opioid analgesic combined with a saccrococcygeal block using bupivacaine. (Campoy, 2013) Post urethral obstruction, the patient must be monitored closely for hydration status, electrolyte imbalance, and analgesic therapy. In cats without evidence of chronic or acute kidney disease, NSAIDs can be administered to provide analgesia and decrease urethral inflammation. In cases where an NSAID is contraindicated, the clinician may use a therapeutic laser to help reduce the inflammation present post catheterization.

Gastric dilatation volvulus (GDV) GDV is characterized by stomach distention and a clockwise rotation. This condition is considered a surgical emergency. Patients presenting with GDV are often large breed canines with deep chests. Presenting problems include restlessness, abdominal pain, unproductive vomiting, dyspnea, and distention of the abdomen. Because most GDV patients present in some form of , it is important that all team members be on hand as multiple events need to be synchronized to ensure maximum patient comfort and survival. The dilated stomach obstructs blood flow through the caudal vena cava, while the increase in gastric pressure decreases blood flow through the portal vein. (Benett, 2010) Initial treatment after physical examination will include IV fluid therapy via either a jugular catheter or large bore catheters in each cephalic vein. Gastric decompression by trocarization is recommended to improve ventilation before general anesthesia is initiated. (Bennett, 2010)Pre-medication as well as analgesia may be achieved with an opioid such as fentanyl, oxymorphone or hydromorphone. In animals that present as very ill, opioid doses can be reduced. Anesthesia can be induced using an opioid and benzodiazepine such as midazolam. Alternatively, etomidate combined with a benzodiazepine can be used. These combinations have very minimal impact on the cardiovascular system as opposed to other induction medications like propofol. Intra operatively inhalant anesthesia can be kept to a minimum by using a constant rate infusion (CRI) of fentanyl/lidocaine/ketamine. This combination will not only provide multimodal analgesia but also lidocaine has the added benefit of being an anti-arrhythmic should ventricular arrhythmias develop. The FLK CRI can be continued in the post-operative period to maintain a steady state of analgesia. Post-operatively, the patient can be transitioned to IV buprenorphine at the clinician’s discretion.

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Hemoabdomen/splenectomy The hemoabdomen patient often presents with signs of hypovolemic shock (pale mucous membranes, rapid heart rate, weak or “thread” pulses, etc.). Often this can be secondary to neoplasia (or a ruptured splenic mass. Before proceeding with the splenectomy patient, attempts should be made to restore the patients’ tissue perfusion and oxygen delivery before general anesthesia. Hypovolemic patients often have simultaneous RBC and protein loss so colloids and other blood products are often needed preoperatively. (Cummings, 2014) Hemoabdomen patients proceeding to surgery can be treated similar to the GDV patient. Pre-operatively an opioid will provide analgesia. Induction can be achieved with an opioid and benzodiazepine combination. The patient should also receive concurrent pre- administration of oxygen via facemask or nasal catheter. Etomidate can also be used for induction combined with a benzodiazepine. Agents such as thiopental or propofol are not recommended due to their common side effect of vasodilation. Again as with GDV patients, a FLK CRI can be a useful adjunct to minimize inhalant anesthesia. The FLK CRI can be continued in the post-operative period to maintain a steady state of analgesia.

Dystocia The patient presenting with dystocia and requiring caesarian section (CS) must be handled very carefully to ensure the safety of the dam as well as . In CS patients anesthetic requirements are often reduced because of increased progesterone levels. There is also a reduced functional residual capacity of the lungs due to the pressure of the intra-abdominal volume of the fetuses. Patients that are not overly anxious or stressed should have an IV catheter placed, abdominal shaving and pre-oxygenation before drugs are administered. If selecting an opioid for pre-medication a mixed agonist/antagonist such as butorphanol may be preferred to minimize fetal respiratory and CNS depression. (Norkus, 2010) A longer acting pure-mu opioid can be administered upon fetus removal to provide analgesia to the mother. Induction cab be achieved using a low dose benzodiazepine (<0.15mg/kg) followed by propofol or etomidate. (Norkus, 2010) Alfaxalone, although not yet available in the United States, looks to be a promising induction agent for sick and debilitated patients such as these. Mask induction is not recommended due to the side effects and exposure to the staff. If staff are so trained, an opioid/local anesthetic epidural can be a very effective analgesic tool that can dramatically reduce the need for inhalant anesthetics.

Trauma Anesthesia and pain management of the trauma patient can be most challenging to the veterinary staff. Many body systems can be affected and concurrent and multimodal therapies are often needed. For the trauma patient, anesthesia should not be initiated until vital organ function has been stabilized. The trauma patient must have a patent airway. The clinician should ensure that circulating blood volume is maintained in order to provide tissue perfusion and oxygen delivery to vital organs. (Wadell, 2010) The goal with pre-medicating trauma patients is to provide analgesia as well as reduce the overall amount of induction agent needed. Agents that are reversible (opioids& benzodiazepines) are preferred to agents that are not reversible (acepromazine, ketamine). An opioid analgesic such as fentanyl is an attractive option in the trauma patient as it is rapidly cleared from the body very quickly, which can help facilitate a neurologic examination. During induction patients should be pre-oxygenated. Induction can be achieved using an opioid/benzodiazepine combination. In some cases this may not be enough to intubate and a small amount of propofol is necessary to facilitate intubation. In cases where increased intra cranial or intra ocular pressure is not a concern a ketamine/diazepam induction may be an attractive choice as it allows rapid intubation and will provide some analgesia. Post-operatively trauma patients must have vigilant nursing care constantly assessing their cardiovascular, respiratory, and pain level. Multimodal CRIs provide constant analgesia without the “peaks and valleys” effect seen with some intermittent dosing of analgesics. Implementing a pain scoring system can help your clinic effectively titrate analgesics to fit your patients’ needs. The University of Colorado offers a species specific color chart available for download. These handouts can be placed in recovery and treatment areas to help train technicians and staff to recognize various pain behaviors. http://www.csuanimalcancercenter.org/assets/files/csu_acute_pain_scale_canine.pdf Working together the veterinary team can implement an anesthesia and pain management protocol to help ensure the comfort and safety of any patient walking through your doors.

References Bennett, RC. Gastrointestinal and Hepatic Disease. 2010. In BSAVA Manual of Canine and Feline Anaesthesia and Analgesia, second edition. pp246- 248 British Small Animal Veterinary Association Cummings,K. & Wetmore, L. Top 5 Emergencies Requiring Anesthesia Clinicians Brief, March 2014 Fossum, TW. Surgery of the Bladder and the Urethra. 2007. In Small Animal Surgery, 3rd edition St.Louis, Mosby-Elsevier Norkus, CL. Caesarian Section Techniques. 2010. In Anesthesia for Veterinary Technicians (editor: Bryant, Susan) Ames, IA: Wiley Blackwell

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Perkowski, SZ. Anesthesia for the Emergency Small Animal Patient. 2000 Vet Clin North America Small Animal Practice 30(3): 509-530 Read MR, and Schroder, CA (2013), The Trunk in: Small Animal Regional Anesthesia and Analgesia. (Editors: Campoy, L. and Read MR) Ames, IA: Wiley Blackwell. Wadell, KA. Emergency Trauma Patients. 2010. In Anesthesia for Veterinary Technicians (editor: Bryant, Susan) Ames, IA: Wiley Blackwell

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Pain Management and Profitability: Stop the Hurt Tasha McNerney, BS, CVT, CVPP Veterinary Anesthesia Nerds Glenside, PA

There are many reasons for providing appropriate analgesia to your patients, and thankfully for the overall economic health of a clinic pain management can also boot your practices bottom line. Providing appropriate or even advanced analgesic techniques not only provides an economic benefit to your practice, but it also improves overall staff morale and job satisfaction. Technicians and nurses are able to identify painful patients and if they are allowed to play an active role in the alleviation of a patients’ pain, they have an overall greater sense of purpose at the clinic and increase in job satisfaction. Technicians who are proud of the level of analgesia provided for acute and chronic painful patients often stay at their place of employment longer. Pet owners are also more educated and expect that their pets pain will be taken seriously and treated appropriately. Whether providing an analgesic regime to treat acute post-surgical pain, or developing a chronic pain plan for a senior osteoarthritis patient, clients have come to expect effective analgesic options. And, many clients are willing to pay appropriately so their beloved pet is not in pain. When looking at the cost of analgesics, any of the drugs used are relatively inexpensive. The opioid analgesic Morphine for example is one of the cheapest yet most effective analgesic options available. It can be used as a pre-medication prior to surgery, or for added revenue to the practice and increased pain control during surgery it can be titrated to the patient via constant rate infusion. Offering specialized analgesic options such as constant rate infusions or anesthetic local blocks can provide additional revenue as the clinic should charge appropriately for the supplies needed and for the expertise and additional training of veterinarians or technicians. Technicians can be trained to administer highly effective local blocks including epidurals. An effective epidural will not only improve patient comfort, but also cut down on the use of inhalant anesthetic during the surgical procedure as well as additional rescue analgesics often needed during surgery. If appropriate local and nerve blocks are used during each surgical procedure and charged a small appropriate fee, the practice will see a considerable difference when that small fee is multiplied by the potentially hundreds of surgeries that are done each year. Some of the simplest ways to provide increased patient comfort and increased revenue without a big investment are as follows 1. Provide regional or nerve blocks to every surgical patient 2. Start using constant rate infusions for pain relief 3. Have a member of your team be the captain of the Pain Police and send them for additional training in analgesic options. 4. Become a member of the IVAPM. www.IVAPM.org By implementing some simple changes and setting an appropriate in clinic point person, your practice will be known as the go to for the best level of pain management.

Resources Epstein, Mark; Pain Management: The Positive Effects on Your Practice and Patients. www.DVM360.com, February 2011. McLain Madsen, L. The Economics of Pain Relief. Veterinary Economics 2007; 48(6): 30-35

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What’s Your Role? A Team Approach to Talking to Pet Owners about Pain Management Tasha McNerney, BS, CVT, CVPP Veterinary Anesthesia Nerds Glenside, PA

Often times pet parents are faced with the decision whether or not to put their pets under general anesthesia for a surgical or dental procedure. They are also often worried about whether or not their beloved pet will be in pain afterwards and how they will be able to best manage this pain. Veterinary team members are often the ones responsible for explaining things to the client to alleviate some of the fear associated with post- operative recovery and pain management. Veterinary team members should also be prepared to discuss chronic pain conditions such as osteoarthritis.

Reception When a client calls the clinic, the receptionist is the front line for obtaining information from the client. Receptionists can ask questions to help get a clearer picture of the painful condition either chronic or acute. Some examples include: 1. How long has your pet been experiencing pain? 2. Does the pain appear to be localized to one area? 3. Is your pet licking or biting at a certain area of the body? 4. Has your pet stopped eating/grooming/jumping/running? 5. Does your pet take a long time to stand after sitting or sleeping?

Technicians/nurses Taking the time to get a complete history will be the key to ensuring proper pain management. Be prepared to talk with clients about acute pain after surgery. Orthopedic procedures and dentistries that have required multiple extractions however, may require a longer recovery time. Also after surgery patients may be unsteady on their feet and unable to walk up or down stairs. If their pet usually sleeps upstairs in bed, it’s important to set up a comfortable area on the first floor for their pet to rest in when they come home, or be prepared to carry their pet up and down the stairs! Also explain to the client that some post-operative pain medications such as opioids may make their pet nauseous and whiny; if this happens they should call the office. Almost every surgical and dental procedure will involve some level of pain. Talk with the client about the expected level of pain and how this pain will be treated. Also talk with the client about the need (if any) for post-operative physical therapy. Orthopedic procedures greatly benefit from post-operative physical therapy such as hydrotherapy, massage therapy, and low level laser therapy. Also, many pain medications have to be administered orally. If it is difficult for clients to give their dog or cat a pill, there are now other drug delivery options to ensure pets stay comfortable in the recovery period.

Doctors The doctors play a very important role in piecing the information together to create the best pain management action plan. By combining patient history with a thorough physical exam a concise and effective pain management plan can be created. The most important aspect of managing pain is to work with a multi-modal treatment protocol. The principle of multimodal therapy is to use analgesic drugs and physical therapy modalities that target several different steps of the pain pathway, allowing more effective pain control with fewer side effects. NSAIDs remain the mainstay of therapy for chronically painful patients. Their principal mode of action is to block prostaglandin production by binding and inhibiting cyclooxygenase (COX). The result of this effect is mainly a reduction in inflammation. Opioids are useful in a variety of painful conditions (though they may have limited effectiveness in some forms of neuropathic pain). Opioids may be particularly useful for chronic pain management, as they are available in oral and transdermal versions. NMDA receptor antagonists are often used as adjunctive drugs (i.e. in combination with other analgesics) to improve the control of pain. Intense and/or chronic painful stimuli result in changes in the central nervous system’s response to input, leading to an increase of pain intensity. NMDA receptor antagonist drugs help to control and treat this “amplification”. Amantadine is the most commonly used oral NMDA receptor antagonist. It was originally developed as an antiviral compound, and has also been used to treat Parkinson’s disease in humans. Gabapentin has been used for many forms of chronic pain, though its best application may be for neuropathic pain. Gabapentin is an anti-convulsant medication with significant adjunctive anti-hyperalgesic action. Gabapentin is commonly used in conjunction with opioids for analgesic treatment options in post- amputation patients.

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Tricyclic antidepressants (TCA’s) have been used in humans and animals as adjuncts to other analgesics (especially opioids) for chronic pain. They act to inhibit serotonin and norepinephrine reuptake, though they may have other analgesic effects as well (including possible actions at opioid receptors and on nerve transmission). Non-pharmacologic therapies for chronic pain management include acupuncture, electroacupuncture and, laser therapy and pulsed magnetic field therapy. Hydrotherapy is also a useful treatment option for patients that have IVDD or osteoarthritis. Often the best course of treatment is to combine physical therapy with pharmacological therapies.

Kennel/support staff Kennel staff also play an important role in recognizing patients in pain. Because patients who are boarding for long periods of time, kennel staff may notice limping, sensitivity when an area is touched, patients that are uncomfortable and unable to rest, or a change in body language. If the kennel staff notices signs of pain in boarding patients, they should alert the nurses or veterinarians so that the owner can be notified and proper pain management plans can be enacted. When all staff members work together, we can create a pleasing pain free environment for our patients. Everyone wins! Another way you can ensure your patients are receiving the most comprehensive pain management plan is to become an IVAPM (International Veterinary Pain Management) member. The IVAPM is an organization that seeks to educate and promote pain management for animals worldwide. It also provides continuing education in the area of pain recognition and treatment. IVAPM members can work toward certification in the management of animal pain. To find a CVPP or IVAPM member in your area, visit the IVAPM website at www.IVAPM.org

References Multimodal Pain Management in Orthopedics: Implications for Joint Arthroplasty Surgery Javad Parvizi, MD, FRCS; Michael R. Bloomfield, Orthopedics, February 2013 - Volume 36 · Issue 2: 7-14 Gaynor, James and Muir, William. Handbook of Veterinary Pain Management, 2009, Mosby. St.Louis. MO Thompson, Dave. Chronic Pain. www.vasg.org/chronic_pain_management.htm, Revised 2011

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The Art of Communication: You Say More than You Think Dani McVety, DVM Lap of Love Lutz, FL

The competence to mitigate pain and suffering by treating diseases and/or symptoms in animals without the ability to communicate both the intentional and potential outcomes of such treatments such that trust and rapport is gained with the client is akin to expecting to know how to ride a bike by simply reading an article about the physics of balance and rotational force. Without the belief and trust that the client and the doctor have the same desired outcome, even if that desired outcome is simply the comfort of the pet, trust and rapport will not be established and the client may not accept the treatment plan that you, as a doctor, went to medical school to learn. As veterinarians we have two parties to serve in almost all areas of medical interaction; the owner/client and the patient. (Shelter medicine is the only exception to this rule, as treatment of animals in a shelter setting rarely include an owner.) In human medicine, the client and the patient are generally the same entity. Even in pediatric medicine, the parent is the guardian of the child, not the owner of that child. The parent generally has the levity to make decisions, but if that decision is not in the best interests of the child (as reasonably determined in a court of law), then the parent will in fact lose the ability to make decisions for that child. In fact, it took a groundbreaking case in 1984 (In re Guardianship of Barry, 445 So.2d 365 (Fla. 2d DCA 1984)) to determine that a parent can serve as proxy for their dying infant child’s wishes, allowing the removal of life support in this case. In veterinary medicine, however, our clients served as proxy for their pet’s wishes in almost every interaction they have with a veterinarian; from the decision to amputate a limb, chose surgical versus medical treatment, and even the removal of “life support” is a common path that the veterinarian must walk the client through on behalf of the pet. Legally, the clients are in fact owners of the patient and our communication and established rapport with that owner is imperative if we are to gain the trust such that our medical knowledge will be put to use for the betterment of the pet and/or the treatment of a disease. Learning how to gain that rapport is where the rubber meets the road! In this interactive talk, we will us real-world examples and demonstrations to illustrate various aspects of nonverbal communication. We will discuss the 4 major types of clients, how to adjust your body language to gain and maintain rapport and trust with them, and how to compensate for problems that may arise. Attendees will be able to immediately identify these clients and implement different ways of nonverbally communicating by both reading their clients’ body language more accurately and changing their own to reach the desired outcome. Important topics we will discuss include: 1. Identify the 4 major types of clients. 2. How to start the conversation: tone of voice to use, where to stand or sit. 3. How to address client concerns and outbursts. 4. Specific words to use (and not use) for different types of clients. 5. How to react and what to say when things do not go perfectly.

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Breed Positivity in Your Practice Ori Scislowicz, BS, LVT CVCA- Cardiac Care for Pets Richmond, VA

A positive outlook can go a long way in your everyday life, as well as within your practice. Unfortunately, many of us have been inundated with negativity from some of our coworkers. We have all worked with that team member who starts the day complaining they are having a bad day and that’s why they may be exuding pessimism all day. This is a very toxic approach to the workplace as it can spread throughout the team, creating an epidemic of unhappiness, and make everyone’s lives much more stressful, as well as their days longer.

What IS a toxic work environment? The enemy of positivity in the workplace is an environment of toxicity. Toxic work environments often have chronically high stress levels, whether that be due to the work being consistently intense, or a fear-based culture. Employees may also have a poor work/life balance, where work is eating into their personal lives and enjoyments. There may be a general lack of enthusiasm and loyalty to the practice. The expectations by the supervisors may be unrealistic, causing team members to feel as though they are constantly failing. Dysfunctional leaders can also create toxicity by bullying the team, poorly communicating, and/or being unwilling to help and communicate.

The repercussions Being part of a workplace consumed by negativity has a detrimental effect on the employees, and ultimately the success of the practice as well. Employees often develop stress-related physical and mental illnesses such as gastrointestinal upset, anxiety, depression, cardiovascular disease, migraines, and musculoskeletal problems. In a 20 year study, published in 2011, researchers at Tel Aviv University found a startling connection between the relationship between the workplace and the individual’s risk of death. Fifty-three individuals had died by the conclusion of the study in 2008. These individuals were significantly more likely to describe their work environment as hostile compared to those who survived.

Adjusting your own perspective Fortunately, there is a lot that is in our own power to change and promote positivity. You ultimately choose how to react to certain circumstances. Although it’s not our natural response, taking on an excessive workload or dealing with a difficult team member/client is much easier when approached with a positive attitude. Remember it’s never a good idea to allow other’s baggage to live rent-free in your head. We push through our lives with all goals meeting a larger goal of achieving happiness. Many team members see work as a necessary evil (and hurdle) to getting closer to that goal. It’s a much healthier outlook to view work as another opportunity to strive for inner happiness as you spend 40 plus hours a week there. Gratitude is also a great way to reframe your outlook amidst negativity at work. Try to remind yourself of what you are thankful for on a daily basis, especially during the most stressful moments. Posture can also play a role in your own perspective of the day. Keeping your posture upright can help improve confidence levels and overall physical health. If you feel well-rested and energetic, you are better able to cope with difficult days. Self-care is very important in combating negativity around you. Giving yourself time around your workday for something that you enjoy can greatly improve your mental state. That optimistic perspective may also rub off on your less than happy teammates. Many of us in veterinary medicine are in a field that utilizes our strengths and ignites our inner passion. Keeping the big picture in mind and continuing to work towards a greater good can help conquer the more difficult days.

Creating an overall positive atmosphere Outside of controlling our own responses to negativity, we can also help battle toxicity and grow a more positive practice. Taking the approach of being energetic, charismatic, and people-oriented can help defuse the group’s stress. If an employee, or even a client, seems stressed at the beginning of the day, try to go out of your way to help them out. Pick up extra tasks, and ask them if they need to talk. If a team member is in a very bad mood, it may be best to take the day off. Team members should not be taking “mental health” days regularly, but a stressed or burned-out employee may need the time once in a blue moon. You’ll find that the day flows much better and the team is more productive (even being short-staffed) without the negative aura. If the behavior continues regularly, then coaching by a manager needs to come into play. Infusing positivity by allowing team members to have a place to look at a family photo, to decorate for the holidays, or even to add plants, is wildly beneficial. Encourage the team to take breaks when they are overly stressed or emotionally overwhelmed, and go for a short walk or listen to an uplifting song.

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Reward systems aren’t just for your pups in the clinic. Team members love to get recognition as well, and it greatly improves morale. Whether it’s a friendly contest to book the most dentals or sell a certain product, or simply a submission box for from fellow team members, a reward system is a must. The rewards can be small too, a $5 or $10 gift card, or ordering pizza for the staff. The benefits to the practice far outweigh the minimal cost. Practices should also be assessed for dysfunctional relationships. Negativity often grows from clique culture, along with insincerity, favoritism, and grudge-holding. Make it clear to new hires that this behavior is unacceptable and will not be tolerated. With current employees, agree to set a new pattern and eliminate these behaviors. If still present over time, coach employees, and even make them go home for the day if they continue to exhibit this unprofessional conduct. There’s no arguing that converting toxicity into positivity is a difficult, gradual process in damaged practices. It is not impossible though. With a strong emphasis on keeping team members satisfied and happy, the practice will see greater output and success as well.

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Bring Fast Success to Your Practice with Modern Marketing Tactics Ori Scislowicz, BS, LVT CVCA- Cardiac Care for Pets Richmond, VA

Taking advantage of marketing opportunities in your veterinary practice will not only help your practice grow but also can give you a chance for personal growth. Marketing is a great creative outlet and a nice way to switch things up in the sometimes cut and dry life of a technician working on the floor. Thanks to our ever growing technologically advanced world, there are many new marketing outlets available. These modern strategies allow for a quick way to expand your outreach into the community.

Inbound versus outbound It’s helpful to understand the difference between inbound and outbound marketing strategies. Inbound is comprised of your modern tactics, including (but not limited to) reaching out via social media, blogging, viral videos, and search engine optimized (SEO) website text. Outbound marketing is more of the “old school” approach, also sometimes referred to as “interruption marketing”. The idea in outbound marketing is to reach out to the largest group of people possible, but it lacks direction and can be considered aggressive. Outbound marketing techniques include advertising (billboards, newspapers), cold calling, and direct . Since the advertising business is trying to push out their message to the general public in as many ways as they can, in the hope of reaching some interested individuals, this can be a very expensive approach. Inbound marketing has a more sophisticated approach, connecting with potential clients through content the viewers would seek by themselves. Originally, this approach may have only accessed younger individuals, but in today’s world, even our grandmothers are on social media. Another advantage of this form of marketing is that a company can interact with their clientele and create a more casual and engaging, as well as less aggressive, exchange.

Social media When your practice decides to explore marketing options through social media, it’s important to understand your potential audience through the various outlets. For example, Facebook users are mostly under 30 years old, with individuals educated minimally at a college level. While Facebook is very popular with women, it has a decent male user as well. Twitter is more balanced when it comes to gender, but mostly consists of users in their late teens to late twenties. Twitter’s users are mostly college graduates, similar to Facebook. Instagram is comprised of more female than male users, with a similarly aged audience as Twitter. While Instagram users tend to have some college experience, they are not mostly college graduates like the previously discussed outlets. Lastly, Pinterest is mostly made up of women, from a wide age range, and only about a third are college graduates. In the world of veterinary medicine, Facebook is a great option for diving into the world of social media. To be successful on Facebook, it does take a certain level of effort and finesse. Your practice must post relevant material for pet parents in order to regularly appear in their feeds. If you are not precise in what you choose to post, it is possible you are wasting precious time trying to reach out to an audience who isn’t listening. The stories that tend to draw people in include patient stories, asking engaging questions, and celebrations. Patient stories are usually very popular- be sure to get the owner’s permission, and post the case with a picture. Questions for your veterinary clients are also a successful attention-getter: ask questions like what their pet is doing for the upcoming holiday, or ask your audience to caption a funny animal photo. Celebrations draw a lot of “likes” as well- whether it be a team member’s professional accomplishment, a pet- related holiday, or a patient’s last chemo treatment. Instagram is the next best social media option for veterinary practices. It focuses on sharing photos with followers, which is what pet parents love to see on your feeds. It’s a great opportunity to success stories and funny pet photos.

Blogging Another great way to reach out to potential and current veterinary clients is through blogging. It’s easy enough to keep up, and also cost-effective. This method helps establish your practice as an authority in the arena of veterinary medicine, and builds trust. Blogging can serve as an easy method of creating viral material that reaches a large audience. If pet parents feel the information posted is worthwhile, they often share this on social media which automatically widens your viewer base. This modern marketing initiative helps initiate conversations with pet owners by allowing for commentary on your posts. If the material is educational and considered valuable by your audience, you will also instill trust and credibility within the pet parent community.

Search engine optimization (SEO) Your practice can put forth as much online marketing efforts as you like, but with a limited audience, your efforts will go unheard. Search engine optimization (SEO) helps lengthen your message’s tentacles across the internet. SEO effects visibility through free

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methods (even better!). The idea here is that the earlier and more frequent a site appears in a pet owner’s search, the more viewers you will obtain. Some of the methods for SEO include editing content, HTML and coding to increase the site’s significance to searched keywords. Content can be edited to include keywords that are frequently searched for, which can increase traffic to your site. Sites also can be promoted by increasing backlinks and inbound links (a hyperlink back to your site from another site). Cross linking between pages of a website can provide an increased number of links and help widen your audience. Content should be frequently updated as well so search engines will regularly direct searchers back.

Videos Incorporating videos into a practice’s marketing campaign helps add another fun and engaging element for pet parents, and can ultimately increase visibility online. You can take the approach of sharing fun pet-related videos that you find, as well as making your own, which can be educational or simply endearing or humorous. The key is to share and create videos that evoke emotion and portray an image or viewpoint that is in line with that of your practice. Videos are often more likely to be shared, so they are much more likely to become viral. It is important to already have your website and social media platform up to date and well established before you begin to push videos. You wouldn’t want potential clients to stumble upon your Facebook account or website and find outdated or minimally engaging material.

Review sites Another element of a practice’s online presence is review sites. In today’s world, consumers can easily access reviews and ratings from others on a multitude of review forums. While we all would like to find nothing but positive reviews under our name, when negative commentary is added, it is imperative to take action quickly. It’s very important to start out by responding to any negative posts, and do so with sincerity. This allows the public to see that you do care how you are perceived by the community, and want to do right by your clients and patients. Reach out to any upset clients directly to discuss the situation further. Prior to that conversation, be sure to research the situation so that you are knowledgeable during your talk and know if your practice truly was in the wrong. Afterwards, if the hospital was at fault, be sure to hold a coaching session with the employees working with the client to ensure that future clients receive a better experience. Also remember to encourage those clients who rave on about your hospital at discharge to submit a review on the review site of your choice. Many review sites even have signs, along with a unique QR code, which you can post in your hospital for clients to easily find you (and hopefully provide you with a public kudos!). Links to your listing on a review site can be included on your practice’s website as well as within the email signature.

Developing a strategy The key to jumping into the of the modern marketing age is to start with a budget. It will cost money to develop a useful, attractive website, and even the free options offer enhancements at a minimal cost that are worth exploration. The rule of thumb is usually 3-5% of your net sales will go to marketing efforts. The following steps are developing a plan and mapping it out on a calendar for the year. Before publicizing your practice, you should be comfortable with your message. Your message should be direct, consistent and relatively straight-forward. It is also worthwhile to consult with a marketing professional or company that has experience with veterinary practices. With the right guidance and approach, your practice will outshine the competitors with ease.

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Going Back to Work after Baby- and Beyond: Tailor Your Career to Fit Your Life Ori Scislowicz, BS, LVT CVCA- Cardiac Care for Pets Richmond, VA

One of the hardest struggles any working adult will face is the balancing act between work and life. Most in the veterinary field are very passionate about their work, and along with commonly working long hours and emotionally tumultuous shifts, the struggle is even more intense.

Step Away! Technology as one of the culprits In today’s world, we are never completely turned “off”. We are generally just an arm’s length away from our phones, making us available via text, call or email all hours of the day. Especially those in managerial and ownership roles may feel obligated to check their work emails regularly at home and respond while they should be off-duty. In a 2011 study performed by the University of Toronto, published in the Journal of Health and Social Behavior, researchers found that women who were contacted by their supervisors, coworkers or clients frequently also reported higher levels of psychological distress. Men were less effected, which they found was due to women harboring more guilt when responding to work matters at home.

Moving on up and other big life changes Another component of the stress is that our Generation Y workforce is moving into management positions much quicker than their older counterparts. This generation is very ambitious, and utilizes technology heavily, which allows them flexibility outside of work, but also allows for them to be constantly available. Moreover, when you have younger individuals in management, they feel the work/life balance burden even more as they are getting married, starting families, and still trying to grow themselves as people. This brings us to the emotional experience of returning to work after having a baby. More women nowadays want to continue working for financial and personal reasons. Your attempt at a balanced life becomes a lot more difficult when you have an unpredictable, demanding little being in the midst. New mothers need not fret, there are many useful techniques for dealing with this challenge. Letting go of your perceived guilt for taking a break for yourself is the first step. Allow other family members, friends or your spouse, to help out with the baby while you get time to yourself. Having time to rejuvenate- whether that be spent exercising, reading a book or going out with some friends, helps make you a more well-adjusted person all around. It’s easier to give your all to your child, family, work and other components of your life when you are taking care of yourself. Reaching out to other new parents can also help make you feel less alone in this new endeavor, and can even help provide some useful life tips. During the difficult spots of parenthood, being able to talk to other parents who probably have been there as well, can be reassuring. If your old schedule is simply not working with your new family, it is always worth discussing with your supervisor. Try to also give some time after you initially return from maternity/paternity leave to settle back in, and make these big decisions when you are less emotional. Thankfully, within veterinary medicine there are a multitude of career options offering different schedules. If working in a clinic is no longer a good fit, it may be worth taking a leap into management, education, or exploring opportunities with veterinary insurance and product companies, or research. Delegation is a healthy habit almost everywhere- at work, and even at home. Although many of us can realize when it is necessary to delegate tasks at work, we hesitate in the home environment. Getting help from a spouse, roommate or even your child (if they are old enough) can help manage the chaos and your stress level. A lot of times one parent does not see how frazzled and exhausted the other one has been until it is discussed. One of the best pieces of advice for a reduced stress life- don’t be afraid to ask for help.

The consequences of an imbalanced life Not taking time for yourself and becoming overworked can wreck mental and even physical havoc on your body. When you work long hours and never take time for yourself and your family, you become mentally depressed, helpless, and stressed. Physically you may begin to exhibit psychosomatic symptoms (when mental stress manifests in physical ailments), such as headaches, stomach ulcers, hypertension and chest pain. The more exhausted and unfulfilled individuals become, the more they withdrawal from enjoyable activities and hobbies, along with relationships. A mental switch is turned to think that personal life is getting in the way of work life, when it’s actually the opposite. Everyday life functions can be affected such as appetite and sleep. As you may guess, if you allow yourself to get to the point you cannot appreciate life outside of work, it is important to remember that your work will indeed suffer as well.

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Getting out of the funk In order to balance your work and life, you must take an active role in ensuring your own mental and physical health. Positive coping skills can be broken down into the following categories: family, emotional, professional, spiritual, social and recreational. It’s very important to have a support system, whether it be in the form of blood relatives, friends, or a partner. These individuals help to provide an outsider’s perspective on how we are dealing with certain obstacles, and are also there for support. Emotional coping skills include being aware when you begin to exhibit signs of burnout and stress and being able to separate yourself from aspects of work that are activating a negative emotional response. This may be due to compassion fatigue or simply spending too many hours at work and not enough time for your own life. Professionally you can cope better with difficulties at work when you get help and advice from coworkers, and rejuvenate yourself with continuing education opportunities. You don’t have to go to church to take advantage of spiritual coping methods. Setting aside time for reflection and meditation can help refresh your spiritual side. Getting in touch with the world around you and letting go of your problems for a few minutes every day can help put life in perspective. Those issues that seemed so important and carried a lot of weight in your mind suddenly seem insignificant. Spending time with friends and your neighbors is great way to enrich your life and separate yourself from your own thoughts. Getting involved in volunteer opportunities can also add a higher sense of purpose. Lastly, recreational coping is a fun and exciting way to cope with life’s stressors. Starting up a new hobby or activity can help make you feel more well-rounded and is a great stress reliever.

Time management Identify what areas of your life are most important to you and discover how much time you spend on each aspect. This exercise will help you decide where to make cuts and where to devote more of your time. Most of us will discover we are spending more time on work or work-related thoughts than we should. Adjusting your own self expectations and learning to say “no” to work-related activities that are intruding on your personal time is an important step. Teach yourself not to feel guilty for taking time for yourself or for needing a change in your schedule at work. Ultimately, we have to perceive our lives as chapters. The work/life balance struggle will be a constant mental project and an ever- changing process. You will go through periods where you spend more time developing your career goals, and other periods where you need to back off and spend more time and effort on other aspects of life, such as family. The key is taking the time to access your life and make sure you are happy with where your journey is taking you.

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Diagnostic Tests for Canine GI Disease: What is Available? Scott Owens, DVM, MS, DACVIM MedVet Indianopolis Carmel, IN

History and physical examination A technician plays a vital role in communication with pet owners, and this includes taking an initial history on why the pet is coming in to the hospital. This may include speaking on the phone and encouraging the visit, or taking the owner in to an exam room and hearing about what made them schedule the visit. This is the first opportunity for the owner to explain the signs they have been observing with their dog, and as such is an excellent opportunity to start establishing a problem list and a list of differential diagnoses. The value of this initial history cannot be overstated, as what the technician relays to the veterinarian is often a stepping-stone towards more targeted questions for the owner.

Baseline lab work A serum chemistry panel, complete blood count, and urinalysis are unlikely to provide a definitive diagnosis for a dog with chronic gastrointestinal disease (such as inflammatory bowel disease), but this is an opportunity to rule out many other underlying causes that could be contributing to the clinical signs. Acute or chronic kidney disease, chronic hepatitis, acute liver toxicity, acute or chronic pancreatitis, and pyelonephritis are all diseases that can initially present very similarly to primary gastrointestinal disease, and these can often easily be excluded on initial lab work. Certain classifications of intestinal disease can also be identified on routine blood work as well, such as hypoalbuminemia. Dogs with hypoalbuminemia and chronic diarrhea, normal liver function, and negative protein in their urine can be characterized as having a protein losing enteropathy, a more severe and chronic type of infiltrative GI disease. Hypercalcemia, hypocholesterolemia, hypoglycemia, and elevated potassium can be suggestive of hypoadrenocorticism (Addison’s disease), which will often present with waxing and waning chronic GI clinical signs.

Radiographs Dogs with chronic regurgitation will often be presented for evaluation of “vomiting”, as many owners are not aware of the difference between the two. This is a classic case of how valuable a clinical history can be, as the diagnostic approach is vastly different for these two problems. If the patient is experiencing regurgitation, thoracic radiographs should be taken immediately to investigate for megaesophagus, as well as for aspiration pneumonia which frequently accompanies regurgitation. Abdominal radiographs are an insensitive tool for primary infiltrative gastrointestinal disease, but can be done to help exclude other causes of similar clinical signs. Hepatomegaly or microhepatica can be seen and are both suggestive of primary hepatic disease. Chronic partial (stomach or small intestine) can be seen as could a cranial abdominal mass effect that might be causing vomiting. Radiograph contrast studies provide limited, insensitive information but can be indicated in some cases. Use of an appropriate amount of barium (15mL/kg) is vital for this test to be consistent and reliable. Administering an inadequate volume will affect standardized motility times and can lead to a false diagnosis. Additionally, strict adherence of timing of follow-up radiographs will also help improve the diagnostic utility of this test.

Abdominal ultrasound Ultrasonography can be a useful test for evaluating the integrity of the . Wall layering and overall wall thickness can be evaluated, identifying both diffuse and focal lesions. Lumen distention and the presence of an acute obstruction can also be appreciated with ultrasound, helping to confirm a presumed obstruction secondary to a mass or foreign object. When the normal structure of wall layering (mucosa, submucosa, muscularis, serosa) is no longer present, neoplasia should be a top differential. Mesenteric lymph nodes can also be evaluated, which are important because they drain the GI tract. In a cat with a diffusely thickened muscularis layer and enlarged mesenteric lymph nodes, for example, small cell GI lymphoma should be high on the differential list. It should be noted that skill of the ultrasonographer needs to be considered when interpreting ultrasound images. There is a steep learning curve when performing ultrasounds and images can be under- and over-interpreted to a fault in some cases. For instance, it should be known that a small intestine that appears normal on ultrasound can still be markedly inflamed with lymphocytes and plasmacytes consistent with inflammatory bowel disease. On the other hand, a diffusely distended small intestine with fluid in the lumen can represent ileus secondary to many other underlying diseases, and does not necessarily mean there is an obstruction.

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Stool analysis A fecal exam for ova and parasites should be one of the first tests performed on a dog that is presented with diarrhea. Standardization of fecal prep in-hospital, or use of an outside diagnostic lab, will help improve the quality of results and increase the ability to get a diagnosis if parasitic disease is present. In addition to a routine fecal flotation, there are other tests that can be performed on the stools. ELISA testing can be performed on stool samples for infectious diseases including Parvo virus and Giardia. These tests are rapid and inexpensive and can be done cage side, helping to reach a diagnosis faster. In cats, the Parvo SNAP test can be used to test for feline panleukopenia. An extensive PCR panel (DNA testing) can be done on stool as well, which tests for various infectious and bacterial diseases including Clostridium, Campylobacter, Salmonella, etc. I advise taking caution when interpreting this type of test, however, as false positives can occur as well incidental findings. A dog with mild chronic diarrhea that tests positive for Coronavirus, for example, likely has a different underlying disease causing the diarrhea. Fecal cytology is another simple test that can be performed in-house. This test is generally done to look either for blood in the stool or to quantify Clostridium spores. While a broad collection of different bacteria is normal for a fecal cytology, seeing a large population of a single bacteria type (especially Clostridium spores) should be considered abnormal. Similar to the fecal PCR test, caution should be taken to avoid over-interpreting these results; there are many causes of bacterial overgrowth so this is generally a symptom and not the definitive diagnosis. A rectal scrape can be performed, primarily looking for intracellular pathogens such as Histoplasmosis. This is a different test from a fecal cytology, as aggressive scraping of the rectal wall should be done to obtain cells in the mucosal layer which may contain the organisms. Fecal occult blood, on rare occasions, can be a useful diagnostic test. To obtain the most accurate results, the patient should ideally be temporarily on a vegetarian diet (meat proteins can cause false positives) and the stools should be evacuated normally. The act of performing a rectal exam to obtain the feces may be just enough to cause a false positive. The purpose of this test is to try and identify microscopic intestinal bleeding. In lieu of feeding the vegetarian diet, a first test could be submitted and if it comes back as negative then no further action may be needed.

The GI panel Cobalamin and folate are commonly measured in dogs with chronic GI disease. These B vitamins are absorbed at different areas in the small intestine (ileum and duodenum, respectively) and their serum concentration can give insight as to the presence / absence of intestinal . The patient should be fasted prior to the blood draw for these samples. In addition to the vitamin panel, TLI and SPEC cPL can also be measured on this panel. Exocrine pancreatic insufficiency (EPI) is an uncommon cause of small bowel diarrhea and weight loss in dogs but is typically simple to diagnose by measuring serum TLI. The SPEC cPL test is the most accurate test available for diagnosing canine pancreatitis (although there are still many false positives and negatives with this test). The SNAP cPL is a cage-side test that has lower specificity compared to the SPEC cPL but can be used as a screening test to rule out the disease. It is important to understand the limitations of this test and to not over-interpret a weak positive, as many other diseases can contribute to this result.

Intestinal biopsies When a definitive diagnosis cannot be determined with the above testing, taking intestinal biopsies should be the next step. For most cases of chronic enteropathy with presumed diffuse intestinal disease GI endoscopy is my preferred method. This allows the clinician the ability to visually inspect a portion of the GI tract, including esophagus, stomach, duodenum, colon, and possibly ileum, as well as to take multiple biopsies from each of these locations. There is low morbidity with this procedure and the patient can generally go home the same day of the procedure, reducing cost and stress on the patient. If endoscopy is not available to the clinician or if a focal mass is identified on ultrasound then an abdominal exploratory surgery should be performed. This gives the clinician the opportunity to palpate the entire length of intestines and take multiple representative pieces of tissue for histopathology. If the surgery was performed for a suspected foreign body and no evidence of an obstruction is seen, then biopsies should still be taken prior to closing the abdomen. The diagnostic approach to gastrointestinal disease can be time consuming and complex but if done systematically with appropriate communication it can be a rewarding experience for both the patient and owner. It is important to remember that therapeutic trials (such as diet and antibiotics) are equally important diagnostic tools that can be used in chronically affected dogs, and to remember that tests done with negative results can be just as important as positive results.

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IBD vs. IBS: The Differing Experiences of Our Patients and Clients Craig Ruaux, BVSc, PhD, DACVIM Oregon State University Corvallis, OR

Inflammatory Bowel Disease (IBD) is a common diagnosis in our companion animal patients. With only a small number of exceptions, companion animal patients with IBD are chronic cases that will likely require frequent visits for veterinary care. Many pet owners also suffer from chronic gastrointestinal diseases, and on occasion the similar sounding diagnoses, such as IBD and IBS (Irritable Bowel Syndrome) will cause clients to anthropomorphize the diagnosis of their pet. The purpose of this presentation is to describe the common disorders we call “IBD” in canine and feline patients, and to compare these diagnoses with the more common inflammatory and non-inflammatory gastrointestinal diseases of human beings. On one level, IBD is fairly easy to understand. Even the name of the condition, Inflammatory Bowel Disease, tells us essentially what is happening. This initially simple situation, however, hides a myriad of subtle differences and altered prognoses. In companion animals, the term IBD encompasses several different histopathological diagnoses. The most commonly diagnosed form of IBD in the dog and the cat is lymphocytic/plasmacytic. As the name suggests, this disease is diagnosed by detecting the presence of increased numbers of lymphocytes and plasma cells (the cells that produce antibodies) in the wall of the intestine. In most areas of the country, lymphocytic/plasmacytic IBD (LP-IBD) is the major form of IBD diagnosed, accounting for about 70% of diagnoses when histopathology is available. The next most common form of IBD in companion animals in most areas is eosinophilic, again referring to the presence of abnormal numbers of eosinophils. Eosinophils are often thought to represent a strong immune response or allergic reaction, possibly to gastrointestinal parasites. Eosinophilic IBD is actually fairly common in the Rottweiler dog, and in this breed it is a common cause of protein losing enteropathy. Between them, LP-IBD and eosinophilic IBD account for about 85-90% of all diagnoses of IBD in dogs and cats. Other rarer forms are occasionally encountered, often these are diseases with a more severe presentation and a worse prognosis. For these other conditions, please refer to Table One in “Chronic enteropathies in the dog”, elsewhere in these proceedings.

Why do animals get IBD? For diseases that are remarkably common in our patients, we know very little about how they come about. In part, this reflects the great difficulty of obtaining samples from the intestinal tract of animals. What we do know, though, is that dysregulation of the gastrointestinal tract immune system, and also dysregulation of the microbiome (bacterial populations) in the gastrointestinal tract both seem to play an important part in developing this disease. As mentioned above, LP-IBD is the most common histological type of IBD we diagnose, and it is thought that this process is driven by increased immune responsiveness, either to proteins in the diet, bacteria that are present in the lumen of the intestine, or possibly even to components of the intestinal wall itself. Just why some individuals develop IBD and others don’t is unclear, but we do know that there are breed predispositions (for instance, German Shepherd Dogs, Rottweilers, Basenji, Shar Pei, pure breed cats), which suggests that there is probably a genetic basis to the disease, but just what this basis is is unknown at this time. Similarly, in humans, people with specific major histocompatibility (MHC) grouping antigen types are more prone to development of gastrointestinal inflammatory diseases. Many dogs with gastrointestinal inflammation, particularly those with lymphocytic/plasmacytic disease, are either intolerant of or allergic to some component in the diet, commonly the animal shows an intolerance to the major protein source of their diet. Because many dogs and cats receive essentially the same diet day in day out for years, the gut is exposed to large amounts of this same protein source over and over. This might be one reason why chronic gastrointestinal disease is becoming so common in our patients, as most animals have far less variety in their diet than their owners do. Eosinophilic IBD suggests that gastrointestinal parasitism may be present. Dogs and cats are frequently infected with gastrointestinal parasites, and these parasites are often cryptic (ie, hard to diagnose). With many of the parasites of companion animals reinfection is common, particularly when yard soil is heavily contaminated with parasite eggs and larvae. For this reason, animals with eosinophilic IBD are often treated with broad-spectrum anthelmintic drugs such as fenbendazole. Because of the high larval loads that some pets are exposed to in their environments, it may take several treatments and changes in husbandry to completely eliminate parasitic infections. Successful control of parasite infestations is a very important part of an integrated approach to control of IBD in dogs and cats. In some cases, dogs and cats may be having an excessive immune response to bacteria that are present in the gastrointestinal tract.

What are the symptoms of IBD in dogs and cats? With so many different disease processes that can end up being diagnosed as IBD, it is no surprise that the clinical signs of IBD in dogs and cats are very variable. In the cat, IBD seems to most commonly affect the stomach and the first part of the small intestine, so

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vomiting, loss of appetite and diarrhea (usually quite mild) are common clinical signs. In many cases owners are not aware that their cat has diarrhea, as the severity of the change is mild and many owners use clumping and dehydrating cat litters that dry out the fecal material before the owner notes that it was a little soft. Owners of indoor/outdoor cats are even less likely to be aware that their cat has diarrhea, and the only thing that they might complain about is loss of appetite, vomiting, and sometimes weight loss. Dogs also develop IBD that affects the stomach (chronic gastritis), but more marked disease in the small intestine and the large intestine is more common in the dog. As owners are more likely to be exposed to the dog’s feces (on walks and in the yard), it is far more common for dog owners with IBD to present their dog with a complaint of diarrhea. If the large intestine is involved (ie colitis), the dog may be having accidents in the house, or asking to go out incessantly through the night. Weight loss and reduced appetite can be seen in some dogs with IBD, but these are less common or secondary complaints compared to the diarrhea in most cases.

What is the situation in humans? Gastrointestinal inflammatory disease in humans is typically one of two diseases, or Crohn’s disease. Sometimes it is impossible to differentiate between the two diseases, this is then referred to as “intermediate colitis”. Ulcerative colitis affects the large intestine, and as the name suggests, is associated with the formation of ulcers and chronic inflammatory lesions. The involvement of the large intestine leads to quite marked diarrhea, often containing blood. Severe bleeding can occur, sometimes to the point of requiring transfusion. Human patients with ulcerative colitis might eventually need to undergo surgery and removal of large sections of the large intestine. Surgical removal of the affected colon can actually cure some human patients with ulcerative colitis. Dogs and cats can develop somewhat similar conditions, ulcerative colitis is occasionally diagnosed in cats, and some forms of colitis in dogs can be quite severe, but these are unusual manifestations of these diseases in our canine and feline patients. Crohn’s disease tends to be found in the ileum, ileocolic junction and the large intestine, although all parts of the GI tract can be affected. The inflammation in Crohn’s disease often features large numbers of neutrophils and the formation of microabcesses. This type of pathology is actually fairly rare in our small animal patients, who as discussed above tend to develop lymphocyte and plasma cell infiltration, and who tend to have inflammation present throughout the intestinal tract, although it may be more prominent in some areas (such as the stomach and duodenum in the cat, or the large intestine in the dog). Crohn’s disease can lead to gastrointestinal tract obstruction, and some patients will need surgery to remove these obstructing areas. Unfortunately, surgery is not curative for Crohn’s disease in humans. Intestinal obstructions or loss of intestinal mobility in dogs and cats with inflammatory bowel disease is very uncommon, so our patients are far less likely to need to have surgery for their disease (although surgical biopsies are often indicated in their work-up). Irritable Bowel Disease, or IBS, is actually more common in human beings than either Crohn’s disease or ulcerative colitis. Some estimates put the number of human patients with Crohn’s disease at 27-48/100,000 people (0.02-0.04%); ulcerative colitis at about 1/600 people (0.16%), while IBS may be present in up to 15% of humans, with many of these cases going undiagnosed. A client who hears that their pet has IBD and says “oh, I have that too” is far more likely to have Irritable Bowel Disease than either Crohn’s disease or ulcerative colitis, and if they do have either of the two main inflammatory diseases they are likely to know them by their more common names. IBS in humans is a quite different disease to the inflammatory bowel diseases. Most notably, inflammation is not a major part of this disease, instead the major symptoms are of increased or abnormal gastrointestinal motility, and often a strong sensation of visceral pain. Humans with IBS may have diarrhea, constipation, or both. In recent years it has become increasingly understood that the neurotransmitter serotonin is an important regulator of the gastrointestinal motility. Some of the drugs used to treat IBS in humans alter serotonin metabolism or serotonin receptors. Interestingly, many commonly prescribed antidepressant medications in humans also alter serotonin metabolism, and many of these drugs can lead to gastrointestinal upset and/or marked worsening of IBS in humans. IBS is also thought to have a psychological component, certainly stress and anxiety can lead to worsening of IBS in human patients. Stress mitigation is a very important part of the management of IBS in humans.

Do our patients get IBS as well? The occurrence of conditions similar to IBS in dogs and cats is an area of some controversy. Most veterinary gastroenterologists would consider this type of diagnosis to be unusual or rare, many feel that IBS does not exist in small animal patients. One problem with this position is that we have very little knowledge of what the normal speed of movement of the intestinal contents should be in dogs and cats, and what we do know is based on complicated measurement techniques that are not feasible for most practices. Thus, we may miss the presence of markedly abnormal GI motility in some of our patients. Opposing this view, we do know that anti- inflammatory steroids help many of our patients with inflammatory bowel disease, where these drugs are not typically helpful in human patients with IBS.

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How do we manage IBD in dogs and cats? The management of IBD in dogs and cats can be a long and drawn out process, it is important that clients understand that there will be periods where their pet will show worsening of clinical signs, and that their pet may not ever be entirely “cured” of this condition. A central part of the management of many animals with IBD is dietary modification. Many of these patients are intolerant to the major proteins in their diet, and a change to a new diet will often be recommended. It is important that the new diet is one that contains proteins that the pet has not previously eaten, and during the initial treatment period the pet must eat only the new diet, no treats, snacks or human food are allowed! The new diet is fed exclusively for at least 14 days. If the pet is going to show improvement with the new diet, it should be obvious within that time. Pets failing to respond to their first elimination diet trial should be switched to another new diet, at this point it is important to emphasize to the client that it is important to try and get to the underlying cause of their pet’s disease, and that finding a dietary intolerance or allergy might allow drug-free therapy. If the pet fails the second diet trial, it is usually time to switch to drug therapy. The mainstay treatment for IBD in both dogs and cats is glucocorticoids such as prednisone or prednisolone given orally. Most cases (about 75%) will show a rapid improvement once the glucocorticoids are started, but the doses necessary will cause some dogs and cats to show Cushingoid side-effects, at least in the first several weeks of therapy. Over time, the doses of steroids can typically be tapered down to low doses on every other day. During this period, it is important that clients understand that most animals with IBD can be managed, and most will eventually be able to have their symptoms controlled. Unfortunately, though, some animals will be more difficult to manage and more aggressive therapies, such as higher level immune suppressive drugs, will be necessary for some patients. It is also important that clients understand that their pet is likely to have flare-ups or reappearance of clinical signs, some times within only a few months of starting their therapy. For some animals, the benefit of therapy is a reduction in the severity or frequency of their clinical signs, they may not be entirely cured. Thus the successful management of animals with IBD requires good, open channels of communication between the pet owner, technical staff of the practice and their clinician.

Further reading The following publications give good overviews of IBD in companion animals and IBS in people. The internet is full of information as well, but much of it is anecdotal, ill-considered or just plain wrong, the sources listed below are considered reputable.

References 1. Guilford WG. Nutritional management of gastrointestinal tract diseases of dogs and cats. Journal of Nutrition 1994;124:2663S-2669S. 2. Spiller R. Serotonin, inflammation, and IBS: fitting the jigsaw together? J Pediatr Gastroenterol Nutr 2007;45 Suppl 2:S115-119. 3. Moynihan NT, Callahan MJ, Kalsmith B, et al. How do you spell relief for irritable bowel syndrome? J Fam Pract 2008;57:100-108. 4. Guilford WG. Idiopathic Inflammatory Bowel Disease. In: Guilford GW, Center SA, Strombeck DR, Williams DA, Meyer DJ, eds. Strombeck's Small Animal Gastroenterology, 3rd ed. Philadelphia: W.B Saunders Company; 1996:451-486. 5. Marks SL. Management of inflammatory bowel disease. Compendium of Continuing Education for the Practicing Veterinarian 1998;20:317-332. 6. Zoran D. Nutritional management of gastrointestinal disease. Clin Tech Small Anim Pract 2003;18:211-217. FamilyDoctor.org IBS:http://familydoctor.org/online/famdocen/home/common/digestive/disorders/112.html IBD:http://familydoctor.org/online/famdocen/home/common/digestive/disorders/252.html National Digestive Diseases Information Clearinghouse http://digestive.niddk.nih.gov/index.htm

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Managing the Canine and Feline Pancreatitis Patient Craig Ruaux, BVSc, PhD, DACVIM Oregon State University Corvallis, OR

Animals with pancreatic inflammatory disease present to us with widely varying clinical signs and widely varying degrees of illness, which can make the treatment of dogs and cats with pancreatitis both challenging and frustrating. In animals with severe acute pancreatic inflammatory disease, successful management relies on careful assessment, monitoring for and anticipating complications, and diligent nursing care. The purpose of this presentation is to review the approach to therapy of animals with differing forms of pancreatic inflammatory disease. As we will see, the approach to the management of cats can be quite different to the management of dogs, due to the different disease processes in cats and their requirement for high dietary protein intakes.

The dog with uncomplicated acute pancreatitis Dogs with acute pancreatitis are usually presented for vomiting, lethargy, and possibly collapse and abdominal pain. When the pancreas becomes inflamed, digestive enzymes and inflammatory cells within the pancreas itself and in the fat and mesenteries surrounding the pancreas set up a dramatic inflammatory response. This dramatic inflammation within the abdomen is essentially a form of chemical , and is exquisitely painful. When examining dogs with pancreatitis, they will often show abdominal splinting, and may grunt or whine when the cranial abdomen is palpated. These dogs will often have been vomiting for some time, and may continue to vomit when they present to the clinic. The main clinical signs in a dog with uncomplicated acute pancreatitis are due to the electrolyte and fluid losses caused by the vomiting, the abdominal pain, and ongoing nausea.1 All of these aspects need to be addressed in therapy of these cases. Fluid losses are often greater than we would anticipate based on examination of skin tent or mucus membrane moistness. With the inflammation in the abdomen, the gastrointestinal tract can stop moving normally, and these stagnant areas of ileus will accumulate fluid, which is not then available in the circulation. For this reason, intravenous fluid therapy is an important part of the therapeutic plans for these patients. Replacement of the lost fluids expands the blood volume, increasing cardiac output to better perfuse the organs. Maintenance of pancreatic perfusion is very important, as ischemia in the pancreas can perpetuate the inflammation and necrosis. Usually, with cases with marked clinical signs but as yet little in the way of complications, aggressive fluid therapy with standard crystalloid fluids (Normosol-R®, Lacated Ringer’s Solution) is appropriate. The fluids should be supplemented with potassium. Ideally, electrolytes are checked on admission and every 6-8 hours of therapy, with dose adjustments made to the potassium. Control of vomiting and nausea is important, this is achieved with antiemetic drugs such as metoclopramide, ondansetron or dolasetron, or maropitant citrate. Of these, metoclopramide is the drug that we as a profession have the greatest experience with, and most clinicians will have the greatest comfort using. Routine dosing with metoclopramide is by IV injection every 8 hours, but the use of a continuous rate infusion (1-2 mg/kg/24 hrs) often results in less side effects, and can be very effective. In our practice, we tend to use maropitant as our first line antiemetic. We find it highly effective in many patients for both anti-nausea and apparent pain control, while the once daily dosing (IV or SC) is convenient. Typically, we will start with maropitant, and if vomiting or apparent nausea continues, we will add dolasetron, given IV once daily. In some patients we need to promote gastrointestinal motility, for these we will add in a metoclopramide CRI, followed by erythromycin and ranitidine if extra pro-kinetic effect is needed. Pain control is absolutely critical to patient comfort and recovery from this condition. With the pre-existing circulatory and gastrointestinal compromise, NSAIDs like carprofen or firocoxib can be quite risky, with an unacceptably high risk of gastrointestinal ulceration and renal failure if the patient’s fluid status has not been properly addressed. Narcotic pain control is recommended. Traditionally, clinicians have instituted “pancreatic rest” in dogs with acute pancreatitis, with the belief that this would reduce ongoing damage to the pancreas. We now know that this is probably unnecessary, and most likely delays the recovery of sick patients. As long as the dog has stopped vomiting for a period of at least 8-12 hours, which often has already happened by the time the patient is admitted for therapy and stabilized on fluids, I am happy to offer food and water. Usually we will offer small meals of lower fat dog foods, as dietary fat does seem to contribute to the development and perpetuation of pancreatitis in many dogs.2 Dietary fat also delays gastric emptying, the longer a meal is in the stomach or upper small intestine the greater the chance there is for vomiting. Bacterial infection plays little to no role in uncomplicated acute pancreatitis, and antibiotic therapy is generally not indicated. Most dogs with uncomplicated acute pancreatitis recover with adequate fluid therapy and pain control. They will usually need at least overnight hospitalization, however many can be discharged within 24-36 hours. Once the dog is willing to eat, urinating appropriately and body temperature is normal, plans can be made to discharge the patient.

Dogs with complicated severe acute pancreatitis The major potential complications of severe acute pancreatitis are the development of acute renal failure, transient diabetes mellitus (which may become diabetic ketoacidosis), severe systemic vasculitis leading to edema, particularly in the lungs, and disseminated 945

intravascular coagulation. In animals with complicated pancreatitis of high severity, the replacement and maintenance of circulating fluid volumes, attention to plasma colloid oncotic pressure, and the promotion of oxygen delivery to the tissues are all critical to successful therapy. Dogs with severe acute pancreatitis have a form of circulatory shock with many similarities to septic shock, and the clinical approach to these two forms of shock is essentially identical. Animals with pre-existing severe inflammatory disease, hypoalbuminemia and multiple organ failure as a result of acute pancreatitis are beyond the therapeutic and management capabilities of most veterinary hospitals, and typically require referral for intensive care if treatment is desired. The prognosis for dogs with acute pancreatitis once they have developed this extent of metabolic derangement is guarded to grave, with mortality rates greater than 75% in some studies.3 Complicated acute pancreatitis, and for that matter any other severe disease process, is a significant metabolic stress to the patient. Nutritional support becomes crucial to the management of severe cases of acute pancreatitis, however it does raise the problem of how do we go about withholding oral intake while attempting to meet the calorific needs of the patient. In human medical practice severe acute pancreatitis patients are often maintained on total parenteral nutrition (TPN). A small retrospective study of nutritional support of dogs with acute pancreatitis has described the use of TPN in dogs with severe acute pancreatitis.4 Another possible route for nutritional support is the through a surgically or endoscopically placed jejunostomy tube.5 These procedures are intricate and time consuming, with the requirement for scrupulous aseptic technique, and thus are probably best performed in dedicated critical care facilities. Over the last several years, our attitude to management of pancreatitis patients has changed quite a lot. One of the biggest changes has been in the institution of early oral nutrition in pancreatitis patients. In our practice, we are generally comfortable to start offering food if the patient has not vomited for >6 hours. We will recommend some sort of assisted nutrition (such as a naso-esophageal tube or even esophagostomy tube) if the patient is unwilling to eat. In the special cases where the dog has diabetic ketoacidosis and pancreatitis, our typical approach is to treat these dogs as if they are “typical” ketoacidotic patients, including insulin and dextrose therapy, and feeding as soon as possible. Initial fluid therapy is with isotonic saline at shock rates, after at least an hour of volume expansion with high rate crystalloid fluids we recheck blood glucose, urea and electrolytes, often these parameters will have improved markedly just with the volume expansion. Either intermittent intramuscular regular insulin or regular insulin CRI’s are administered following typical protocols for the management of diabetic ketoacidosis, as described elsewhere.6 When the blood glucose has fallen below 200 mg/dL, food and water are offered. In these cases, the pancreatitis often appears to be secondary to the diabetic ketoacidosis, and management of the fluid, electrolyte and endocrine complications of the DKA leads to resolution of the pancreatitis. Dogs with this level of disease will invariably require close and scrupulous care. They are often non-ambulatory, and will need close monitoring of their bladder and bowel functions. Cages must be kept clean and dry, both for patient comfort and to maintain fluid line hygiene. Pain control is just as important in these cases as in the less complicated forms, even though the patient may not be showing overt signs of pain due to their dullness or recumbency.

The dog with chronic pancreatitis Chronic pancreatitis in dogs is often treated in an outpatient setting. Dogs with chronic pancreatitis still experience abdominal pain, often manifested as the “prayer posture”, and often show periods of inappetance or occasional vomiting. Most dogs with chronic pancreatitis have mild disease, and may vomit occasionally, but they usually are not dehydrated or hypovolemic as is seen with the more severe acute pancreatitis cases. Dogs with chronic pancreatitis are managed by diet change in most cases, with the emphasis being on providing a diet with the lowest fat content the dog will tolerate.2 In most dogs, a low fat diet regime and avoidance of table scraps or human food will usually result in a reduction of the frequency that they show clinical signs and resolution of abdominal pain. Some breeds, particularly the Miniature Schnauzer, are at higher risk for the development of chronic pancreatitis and new owners should be counseled on the clinical signs of this condition and the need to avoid high fat foods. In some cases, where fat restriction has not resolved clinical signs, glucocorticoids at low doses or cyclosporine may be necessary to control inflammation. Dogs with chronic pancreatitis will sometime experience more severe flare-ups of their disease, and might need hospitalization with fluid therapy and narcotic pain control as described above.

The cat with pancreatitis Cats always have to be different, and with pancreatitis they are definitely different to the dog in many ways. For a long period we believed that cats basically did not get pancreatitis, as the acute severe presentations with vomiting, fever and dramatic abdominal pain were and are rare in cats. We now know that cats have been hiding their pancreatitis from us, and many cats that present for veterinary care for sporadic vomiting, inappetance or generally “feeling off” actually have pancreatitis. Astonishingly, in a large study of cat pancreases at necropsy, the overall prevalence rate for chronic pancreatitis was 67% in ill cats, and even more remarkably, 45% in normal cats.7 Far from being uncommon, it is now apparent that pancreatic pathology, and particularly chronic pancreatitis, is very common in the domestic cat.

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As well as hiding their pancreatic disease from us, cats tend to have a quite different form of pancreatitis to dogs. In the cat, most cases of pancreatitis feature lymphocytic infiltration and fibrosis. Breakdown of the cells of the pancreas and release of pancreatic enzymes are not present, or are of only minor importance.7 This means that fat restriction, the mainstay of treatment for chronic pancreatitis in dogs, is less likely to be effective in the cat. In many cats, the pancreatitis is a part of a complex of inflammatory diseases affecting the abdominal organs, such as IBD and cholangitis. For many cats, dietary modification to a novel protein source diet, as we do for IBD, seems to help control the clinical signs of pancreatitis as well. The author’s preference is to place cats with chronic pancreatitis on higher protein, novel protein, lower carbohydrate diets where possible. Cats with chronic pancreatitis may develop diabetes mellitus, either due to loss of their islet cells with ongoing inflammation, or the development of insulin resistance with obesity and stress.8 Early dietary interventions to prevent obesity and avoid the development of diabetes mellitus often also seem to assist in the control of these cat’s chronic pancreatitis and other inflammatory abdominal diseases. Pain control, maintenance of adequate nutritional intake in cats with inappetance, and maintenance of hydration are all critical to success. Most cats with chronic pancreatitis presenting to companion animal practices are able to be managed on an outpatient basis, but the owner should be counseled on the need for close monitoring of food intake and the possibility of worsening of the disease which may require hospitalization for fluid therapy and assisted nutrition.

References 1. Ruaux CG, Williams DA. Advances in the management of acute pancreatitis in dogs. CPD Veterinary Medicine 2000;3:8-11. 2. Zoran D. Nutritional management of gastrointestinal disease. Clin Tech Small Anim Pract 2003;18:211-217. 3. Ruaux CG, Atwell RB. A severity score for spontaneous canine acute pancreatitis. Australian Veterinary Journal 1998;76:804-808. 4. Freeman LM, Labato MA, Rush JE, et al. Nutritional support in pancreatitis: a retrospective study. The Journal of Veterinary Emergency and Critical Care 1995;5:32-40. 5. Jergens AE, Morrison JA, Miles KG, et al. Percutaneous endoscopic gastrojejunostomy tube placement in healthy dogs and cats. J Vet Intern Med 2007;21:18-24. 6. Macintire DK. Emergency therapy of diabetic crises: insulin overdose, diabetic ketoacidosis, and hyperosmolar coma. Vet Clin North Am Small Anim Pract 1995;25:639-650. 7. De Cock HE, Forman MA, Farver TB, et al. Prevalence and histopathologic characteristics of pancreatitis in cats. Vet Pathol 2007;44:39-49. 8. Mansfield CS, Jones BR. Review of feline pancreatitis part two: clinical signs, diagnosis and treatment. 2001;3:125-132.

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The Wonderful World of Exotics: An Introduction to Exotic Mammal Medicine Julia Whittington, DVM University of Illinois Urbana, IL

Providing veterinary care to exotic pets is challenging and rewarding, offering the veterinary technician the chance to work with a wide variety of species. There is an inherent challenge for those working with these pets given the large variety of species presented for care. Often the standard organization of a veterinary hospital is not ideal for exotic pets and special accommodations must be made. More time may be required to perform the physical assessment and diagnostic evaluation of exotic pets due to the need to obtain an in-depth history and the sometimes fragile state of these patients. Critical care is an integral part of disease management in zoological species and a high mortality rate is inherent in exotic animal emergency medicine. The nature of these species and the fact that they are fairly recently domesticated dictates that they hide their illness until they have decompensated. Owners need to be aware that their pet is in serious condition but by providing nursing care, you provide them with the best chance for their pet’s recovery. Additionally, front office and support staff must be knowledgeable about exotic pet care and should receive training regarding their handling and husbandry to optimize service of an exotic animal practice.

Natural history and husbandry It is important to educate your team regarding species identification and the natural history of the species you’re seeing. Certainly years can be spent learning all there is to know about every species kept as a pet, but a general working knowledge of those commonly kept will lend confidence to your client interactions. In addition, knowing the natural history of the species presented to you will help you identify the husbandry requirements of that animal when kept in captivity. The goal in keeping any exotic pet is to maintain it in an environment that is as close as possible to that it would be living in if it were free ranging. Often the presenting problem of an exotic pet is related to deficiencies in the environment or their diet. Being familiar with the husbandry requirements of a species will help you identify potential problems and give insight in implementing treatment recommendations. It will also allow you to help your clients determine if that particular species would make a good pet for them based on their circumstances.

History A complete history is of paramount importance in providing you with all the information needed to adequately assess the health of the exotic patient. Developing a pre-printed history form will facilitate this process by identifying problems in husbandry to help focus your exam and make specific care recommendations. Additionally, if concerns regarding the patient’s husbandry are addressed prior to the onset of problems, you have provided your client with excellent preventative health care for their pet. Sample history questions should include:  How long have you owned this pet?  Where did you acquire this pet?  What is this pet’s diet (be specific)?  Are vitamin supplements or medications used for this pet?  Is water provided for this pet? In what manner?  How is this pet housed? Describe any cage furnishing the pet has access to.  What substrate is used in the pet’s enclosure?  How often is the cage/enclosure cleaned?  What is the temperature & humidity of the pet’s environment?  What light is provided for the pet (be specific)?  What other animals have your pet been exposed to?  Have you recently added any new pets to your household (within the last year)?  What problem is your pet currently experiencing?

Preparedness Many exotic pets requiring hospitalization and nursing care are presented in critical condition. As with domesticated species, the time to prepare for emergencies is before the emergency occurs. Work with your care staff to create a plan to respond to medical emergencies. Most of the supplies and equipment used for emergency care of traditional pets can be used to care for zoological species, but some additional supplies will be needed. Prepare a space in your facility that is ready to care for exotics. Include small gauge needles and small syringes, small endotracheal tubes, and drug doses for exotic species in your crash cart. Organize and hold training sessions to practice emergency techniques on exotic species, using cadavers or models to hone your skills and those of your

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support staff. Every good team has members that know their role in an emergency and are prepared to perform it. Make sure your team members are ready.

Triage examination Patient assessment is part of any good triage examination whether the patient has just arrived for an emergency or it is being evaluated after a night of hospitalization and care. It is important to visually assess the patient prior to an actual physical exam. Many zoological species are stressed when in unusual situations and are intolerant to handling and the stress it induces. As animals in critical condition may decompensate from a simple physical examination, decisions must be made as to how much the animal can tolerate at any given time during therapy. It may be necessary to perform diagnostic testing and treatment administration in a staggered fashion, allowing the patient recuperation time between handling periods. Some animals benefit from sedation or anesthesia to minimize perceived stress.

Basics of nursing care Supplemental heat is critical for patients that have lost or do not have the ability to thermo-regulate their own body temperature. This is especially true of avian and reptilian species. Providing an external heat source reduces the physiological stress on the animal during hospitalization care. This can be done with the use of pediatric or veterinary incubators. Often, used pediatric incubators in good working order may be obtained from human hospital surplus stores. Alternatively, radiant heating lamps may be attached to cage doors or placed over aquaria to provide ambient heating when an incubator is unavailable. In this instance, it is important to ensure that the patient and potentially flammable materials are not in direct contact with the lamp as burns and fires are possible. Heating pads and heating discs are good alternatives for providing supplemental heat for patients that are ambulatory and do not need constant thermo-regulation. Temporary heat may also be provided with hot water bottles or rice filled socks that area heated in the microwave. This is especially useful post anesthesia or surgery. A non-ambulatory animal should never be left on a focal heat source without constant monitoring as they may become hyperthermic and not be able to move away from the source to cool down. Additionally, caution must be used when using heating pads for rodent species as they may chew on the power cord leading to electric shock. Nutritional support must be provided to hospitalized patients, especially those with high metabolic rates where anorexia rapidly results in . The caloric requirements of the patients must be calculated and those requirements met on a daily basis through self or supplemental feeding. As in domestic species, metabolic rates are measured in kilocalories per day (kcal/day). The basal metabolic rate (BMR), or metabolic rate at complete rest, equals the patient’s weight measure in kilograms multiplied to the 0.75 power times a species coefficient (K). The species coefficient takes into account the type of animal’s metabolic rate. Once the BMR is calculated, the maintenance energy requirement (MER), the metabolic rate based on activity), can be determined by multiplying the BMR by the activity level of the patient (1-2, 1.5 for convalescing animals, 2 for growth).  BMR kcal/day = K x Weight kg (0.75)  MER kcal/day = 1.5 x BMR  K values (placental mammals-70, marsupial mammals-48) Once the number of kilocalories needed for MER are determined, the amount of food needed to meet that requirement can be calculated and divided over the day’s feedings. The best way to determine if a patient is receiving appropriate nutrition is to weigh the patient daily on an accurate gram scale. Supplemental feeding can then be adjusted as appropriate.

Nursing care of ferrets Ferrets are very resilient and can generally recover well from critical situations. Caution is warranted as even the nicest ferret will bite when uncomfortable or ill. Public health protocols developed for domestic canines should be implemented in response to bites from ferrets. Aggressive or uncooperative ferrets may be restrained for short procedures by providing anesthesia or sedation. A sedation protocol using midazolam (0.5 mg/kg) and butorphanol (0.2 mg/kg) has been effective in the author’s experience. Isoflurane or sevoflurane gas anesthesia administered by mask is also commonly used. Hospitalization considerations A standard hospital cage is appropriate for ferrets and a litter box should be provided with paper based litter. A towel or hide box is also appreciated as these animals will burrow. Water should be provided in a bowl or sipper bottle, depending on what the ferret is accustomed to, and a high quality kitten food or ferret food should also be provided. Have the owner provide the food that the ferret is used to as some are finicky eaters. If the ferret is not eating on its own, syringe feed a gruel carnivore diet (Eukanuba Recovery, Science Diet A/D, chicken baby food, Oxbow Critical Care for Carnivores, Lafeber Carnivore diet) at a rate of 12-20 ml every 4-6 hours. Syringe feeding may be enhanced by scruffing the ferret and placing the catheter tip at the corner of the mouth to administer small amounts of food at a time. Fluid administration The cephalic vein is most often used for IV catheterization. A 24 gauge catheter can be placed in the cephalic vein of most ferrets unless dehydration is pronounced. The skin over the vein should be nicked prior to placement to avoid barbing the catheter as ferret 949

skin is very tough. The catheter is then secured using tape and bandaging. IO catheter placement is typically performed in the proximal femur using an appropriately sized hypodermic or spinal needle. The skin is shaved and aseptically prepared in a routine manner. It is best to anesthetize the ferret prior to this method although a local anesthetic block may also be used. Heparinized saline should be used to keep the catheter patent. Fluids can be administered by SQ, IV, or IO routes. SQ fluids are administered in the intra- scapular area. A large gauge needle should be used as ferrets find this route to be uncomfortable and rapid infusion of warmed fluids is preferred. Fluid requirements are 60-70 ml/kg/day. Fluid therapy instituted for treatment of shock should follow protocols developed for domestic felines. Drug administration The injection sites for drug administration are similar to those used in domestic pet care. Subcutaneous injections are generally administered in the intra-scapular area; intramuscular injections are administered in the quadriceps muscle mass on the cranial thigh. Oral administration of drugs follows the same technique used to syringe feed a ferret.

Nursing care of rabbits and rodents These species are exquisitely sensitive to stress. Even when therapy seems to be progressing well, these animals can become compromised quickly. As such, supportive care is critical to their management. When stressed or in pain, rabbits and some rodents (guinea pigs, chinchillas) will not eat, leading to gastrointestinal problems (stasis, etc.). These complications can often be more critical than the presenting problem. Rabbits and some rodents (guinea pigs, chinchillas, hamsters, degus) have hind gut fermentative digestion which makes them extremely sensitive to certain antibiotics. Avoid using any beta-lactam (penicillins, cephalosporins), tetracycline or macrolide antibiotics with oral administration. Isoflurane anesthetic restraint can be administered by mask or chemical sedation induced if immobilization is required for a brief period of time. Be sure to monitor respiration and heart rate while anesthetized. Hospitalization considerations A standard hospital cage or aquarium with lid is used when hospitalizing rabbits and rodents depending on the size and species of the patient. Newspaper or towel bedding is appropriate. Hide boxes are appreciated by many of the small rodent species. Litter boxes should be provided to rabbits using a paper based litter. Food and water should be made available at all times. Water should be provided in either a bowl or bottle depending on which the animal is used to. Most small mammals are sensitive to heat, thus heating pads can be used for supplemental heat under a towel but be sure the animal can move away from the heat source should they becomes over-heated. Supplemental heat is not necessary unless the patient is hypothermic. Pellets, hay, and fresh salad greens may be used to tempt the anorexic rabbit or large rodent to eat. Seed mixes and pellets are generally offered to small rodents. Do not give seeds to large rodents or rabbits. If the patient is not self-feeding, syringe feeding should be implemented using herbivore gruel diets (Oxbow Critical Care for Herbivores, blenderized pellets, canned pumpkin, and vegetable baby food). Small mammals are fed 50 ml/kg/day divided into feedings every 6 hours. Syringe feeding of rabbits and large rodents (guinea pigs, chinchillas) is facilitated by placing the patient on a flat surface wrapped in a towel “burrito”. A small syringe (1-3 ml) filled with gruel is introduced into the mouth caudal to the incisor teeth. This gap between the incisors and cheek teeth (diastema) is an area through with the syringe can safely pass. The food is then introduced into the caudal oral cavity, allowing the animal to chew and swallow before the process is repeated. Fluid administration A 24 gauge IV catheter can be placed in the cephalic veins of rabbits, chinchillas, and some guinea pigs. Additionally, IV catheters can be placed in the marginal ear vein of rabbits. For small rodents and patients where IV access is compromised, IO catheter placement is indicated. IO catheter placement in rabbits, guinea pigs, and chinchillas performed using the proximal tibia. IO catheter placement in small rodent species is most easily accomplished using the proximal femur. IO catheters may be left in for 3-5 days. IO catheter placement should be performed with the patient sedated or anesthetized. Fluids can be provided by SQ, IV, or IO routes. Maintenance fluid requirements for most small mammals range between 60-100 ml/kg/day, with the average rate being 70 ml/kg/day. Shock fluid rates are 90-100 ml/kg/hr as needed. These fluids can either be given as constant rate infusion or as intermittent boluses. A syringe pump is extremely useful in fluid therapy administration for small mammals. Drug administration SQ injections are given in the intra-scapular area. Use caution to avoid injecting into the cheek pouches which may extend into the intra-scapular area in some rodents (hamsters). Guinea pigs and rats typically object to subcutaneous fluid administration. Intramuscular injections are administered into the quadriceps muscles on the cranial thigh or the semimembranosis-semitendinosis muscle mass on the caudal thigh. Oral drug administration is performed in the same manner as syringe feeding.

Resources A Veterinary Technician’s Guide to Exotic Animal Care. 2nd ed. Tully T.N. and Mitchell M.A., eds. 2012. AAHA Press, Lakewood, CO. Exotic Animal Medicine for the Veterinary Technician. Ballard B. and Cheek R., eds. 2010. Wiley-Blackwell, Ames, IA. Veterinary Nursing of Exotic Pets, 2nd ed. Girling SJ, ed. 2013. Wiley-Blackwell, Ames, IA.

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Anemia: It’s Not Only About Bleeding Kenichiro Yagi, BS, RVT, VTS (ECC, SAIM) Adobe Animal Hospital Los Altos, CA

Anemia, most accurately described, is a deficiency in the blood’s oxygen carrying capacity due to a reduction in the circulating red cell mass. Measurement of total red cell mass requires specialized testing and is difficult to accomplish in clinical practice. Measurement of PCV, HCT, hemoglobin (Hgb), and RBC count are more common methods in the assessment of erythrocyte content of blood. Thus, anemia is commonly defined as a reduction in these values, and occurs when the rate of red blood cell loss or destruction exceeds the rate of production. Anemia is caused by various diseases, many of them resulting in the patient requiring immediate attention.

Functional role of red blood cells Erythrocytes or red blood cells (RBCs) exist mainly to transport oxygen obtained through the lungs to body tissues. The cell’s functions are devoted to optimizing oxygen delivery, with all of its potential energy directed towards maintenance of enzymatic and hemoglobin function, as well as cell integrity. The general structure of RBCs involves a cell with no nuclei or organelle and no ability to produce proteins. Therefore, a mature red blood cell must have its full set of proteins to function appropriately. The RBC’s oxygen carrying capacity is very much dependent on hemoglobin, an iron-porphyrin-protein complex. Hemoglobin is synthesized during the erythrocyte’s development to its mature form. The molecule is a tetramer of heme groups working in cooperation to load and unload oxygen molecules. The percentage of heme groups bound to oxygen molecules is characterized by the oxygen-hemoglobin dissociation curve, visualizing the relationship between partial pressure of oxygen in the blood vessel and oxygen binding. Affinity of hemoglobin to oxygen can be affected by various factors, such as temperature, presence of hydrogen ions (pH), and presence of 2,3 diphosphoglycerate (2,3 DPG), altering the ability for transfused RBCs to deliver oxygen in specific conditions.

Erythropoiesis RBCs are produced through a process called erythropoiesis. Hematopoietic stem cells are progressively differentiated into numerous precursors, eventually expelling their nuclei and developing into reticulocytes, which develop into erythrocytes in 3-4 days. This process is regulated by a hormone called erythropoietin (EPO), which signals for the production of new RBCs. EPO is a glycoprotein produced mainly by the peritubular interstitial fibroblasts in the kidney, though the liver contributes to a small amount of production in anemia. Autocrine production of EPO by erythroid progenitor cells has also been observed. There is a normal amount of erythropoiesis, or basal erythropoiesis, which replaces RBCs living out its life span, maintaining the total red cell mass in a normal range. Upregulated erythropoiesis in response to an increased EPO production stimulated by inadequate oxygen carrying capacity and resultant hypoxemia and hypoxia (leading up to a 1000-fold increase in severe hypoxia) is called stress erythropoiesis. Any cause for anemia, such as hemorrhaging or hemolysis, can trigger EPO production with a noticeable increase in serum EPO level observed within minutes. Reticulocytes are seen within 3-5 days after EPO level is increased, and take another 3-4 days to mature into erythrocytes. Patients seen within 3 days after the blood loss are said to be in the “pre-regenerative” state with no increase in reticulocyte count. If the blood sample of an anemic patient is showing increased reticulocyte count, the patient has a “regenerative” anemia. Patients without an increase in reticulocyte count after 5 days of ongoing anemia may have “non-regenerative” anemia.

Normal RBC lifespan Canine RBCs have a normal life span of 100-115 days, while feline RBCs normally live 73 days. RBCs are taken out of circulation as age-related damage occurs. Age-related damage includes compromise in rheological properties due to membrane deformability loss, immunologic removal through IgG binding and opsonization, reduction in antioxidant defenses leading to denaturing of hemoglobin, and compromise to membrane structure through peroxidation of the phospholipid bilayer (oxidative damage). These damaged cells are removed by the macrophages of the mononuclear phagocyte system, involving the spleen, liver and bone marrow.

Types of anemia RBC loss One of the most common causes of anemia is an increased rate of RBC loss. Blood can be lost through internal or external hemorrhaging. Internal hemorrhage can involve blood loss into the internal spaces. such as peritoneal, retroperitoneal, pleural, pericardial, and gastrointestinal spaces. There are numerous causes of internal and external hemorrhage. Trauma, surgical accidents, and ruptured neoplasms can cause physical damage to vessels resulting in acute or gradual hemorrhaging. Coagulation factor deficiencies, thrombocytopenia, and thrombocytopathia may render a patient unable to prevent bleeding from normal damage to the

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vasculature. Parasitism can lead to external hemorrhage (fleas, ticks, lice) or internal hemorrhage (Ancylostoma, Uncinaria). Gastrointestinal ulcers and hemorrhagic gastroenteritis are GI specific sources of hemorrhage. Anemia due to hemorrhaging is usually regenerative. RBCs lost internally may be placed back into circulation through the lymphatic system, or removed from circulation by macrophages, and their components are recycled. Plasma, RBCs, and its iron content cannot be recovered with external hemorrhaging. Hemorrhage leads to a reduction in red cell mass as well as a compromise in perfusion, leading to reduced oxygen delivery. Dogs have a total blood volume of 78-88ml/kg, while cats have a total blood volume of 62-66ml/kg. Blood loss exceeding 20% leads to significant hypotension, and a loss exceeding 30% will lead to hypovolemic shock and possible death. Treatment of RBC loss through hemorrhaging is directed at maintaining oxygen delivery through providing adequate perfusion and oxygen carrying capacity. Fluid therapy to address hypovolemia is warranted to ensure perfusion to vital organs. Restoration of a normal blood volume will not be possible without addressing the source of the hemorrhage. Locating the source of the blood loss may be more obvious in the case of external hemorrhaging, but may prove to be a challenge if internal. Hemorrhaging from trauma, surgical accidents, and ruptured neoplasms are often stopped through surgical intervention. Coagulation factor deficiencies warrant replacement through appropriate plasma products. The cause of thrombocytopenia and thrombocytopathia should be addressed with appropriate therapy, and platelet transfusions administered if the hemorrhaging is life threatening. Correction of hemostatic disorders should ideally be accomplished before surgical intervention, if warranted. Ectoparasite and endoparasite infestations will require the appropriate anti-parasitic. Gastrointestinal ulcers will require removal of causes and supportive care. If the patient is showing a rapid decline in lab values related to red cell mass (PCV, HCT, or Hgb) or showing clinical signs of hypoxia due to the anemia, a red blood cell transfusion is warranted. Clinical signs of anemia may vary slightly due to the cause of anemia. In general, any form of anemia is associated with paleness. Patients who have compromised delivery of oxygen will exhibit signs of weakness, exercise intolerance, lethargy, fatigue, and sometimes collapse. Their mentation may be dulled due to brain hypoxia. In acute anemia, a prolonged capillary refill time (CRT) due to peripheral vasoconstriction to shunt blood to vital organs may be seen (Patients with chronic anemia will show a normal CRT). Tachycardia, tachypnea, and bounding pulses without other explanations also point towards compromised oxygen delivery. RBC destruction Various types of defects in RBCs can cause an increased rate of destruction leading to anemia. Anemia due to hemolysis results in lowered red cell mass and subsequent reduction in oxygen carrying capacity without significant changes in plasma volume. Hemolysis can be intravascular (destruction of RBC within the blood stream), extravascular (phagocytosis by macrophages in the spleen, liver, bone marrow, and lymph nodes), or both. Intravascular hemolysis will result in the presence of free hemoglobin in the plasma, leading to hemoglobinemia and hemoglobinuria (when renal threshold is exceeded). Hemoglobinuria leads to tubular necrosis resulting in acute kidney injury in humans, and poses similar concerns in veterinary medicine. Jaundice may be seen in patients with RBC destruction rate exceeding the liver’s ability to process bilirubin. In addition, the presence of red blood cell fragments may trigger disseminated intravascular coagulopathy. Extravascular hemolysis can lead to splenic enlargement, though other intravascular signs of hemoglobinemia, hemoglobinuria, and jaundice are not seen. Hemolytic anemia is usually regenerative. Genetic defects of red blood cells, though rare, can cause hemolytic anemia. Elliptocytes, stomatocytes, and pyruvate kinase defect lead to reduced life span due to abnormalities in RBC membrane and shape. Spectrin deficiency and phosphofructokinase defect lead to reduced life span by increasing the fragility of RBCs. Hemolysis is most commonly caused by acquired RBC defects, resulting in direct membrane injury or osmotic lysis. Exposure to chemicals and drugs that cause Heinz body formation will lead to removal of these red cells from circulation through the phagocytic system or cause direct lysis. Causes of Heinz body formation include toxins contained in food (onion, garlic, propylene glycol), drugs (acetaminophen, vitamin K1 and K3, benzocaine), and chemicals (copper, naphthalene, skunk musk, zinc). Cats are more prone to Heinz body formation, but are also more forgiving towards red cells containing Heinz bodies, allowing for a longer survival time. Because of this, feline RBCs may show Heinz bodies without anemia. Cats can develop Heinz bodies when exposed to propylene glycol, and are more prone if inflicted with diabetes mellitus, lymphoma, or hyperthyroidism. Cats with diabetes mellitus or hepatic lipidosis can develop hypophosphatemia which also can cause hemolysis. Phosphate supplementation is recommended if a phosphate level below 0.5mmol/L is seen. Intraerythrocytic parasites such as Babesia canis and Cytauxzoon felis, can lead to hemolytic anemia as well. Hemolysis may be caused by antibody or complement response to the surface antigens of red blood cells by the patient’s own immune system, termed immune-mediated hemolytic anemia (IMHA). Extravascular hemolysis can result from an immunoglobulin G (IgG) mediated type II hypersensitivity (cytotoxic) reaction. Phagocytic loss of RBC membranes reduces the surface area of the RBC, leading to formation of spherocytes (RBCs that have lost the biconcave structure). Gross agglutination of red cells may also be seen. If the immune response is initiated by factors such as cancer, drug administration, or infection, the hemolytic anemia is considered to be secondary IMHA. Passive acquirement of anti-red cell antibodies through blood transfusions and colostrum can cause an IMHA as well. The latter results in a phenomenon called neonatal isoerythrolysis, where anti-red cell antibody is passively acquired by a

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nursing neonate, resulting in the destruction of red cells. When no causative agents can be identified, the hemolytic anemia is considered to be primary IMHA, or auto-immune hemolytic anemia (AIHA). Changes in rheology and passage of RBCs through narrow vessels can cause mechanical and shearing damage to the membranes. Hemoglobinemia and hemoglobinuria result as this is a form of intravascular hemolysis. Fragmented schistocytes and keratocytes are seen on blood smears as an indication of mechanical damage. Patients with cardiac disease, severe heartworm infection, hemangiosarcoma, patent ductus arteriosus, and any other causes of altered blood flow and microangiopathy may show signs of fragmentation of RBCs. DIC can be a cause of fragmentation, and at the same time precipitate DIC. Efforts in treatment of hemolytic anemia are directed towards removing the cause of the hemolysis, and supporting oxygen carrying capacity as needed. Genetic disorders typically cannot be completely resolved, though patients with disorders leading to hemolysis through the mononuclear phagocytic system may benefit from a splenectomy. Exposure to chemicals inducing Heinz body related hemolysis should have the source removed (change in diet, surgical removal of the ingested copper or zinc material). Some toxins may have antidotes such as acetylcysteine in acetaminophen toxicity. Therapy for mechanical injury induced hemolysis is directed at the underlying cause. IMHA is treated with immunosuppressive agents such as glucocorticoids, cyclosporine, mycophenolate, azathioprine, and intravenous immunoglobulin. Regardless of the cause of the hemolysis, when the anemia leads to clinical signs of hypoxia, oxygen carrying capacity is supplemented. Packed RBC (pRBC) transfusions are typically the ideal choice as hemolytic anemia does not cause blood volume loss. pRBC will provide oxygen carrying capacity while minimizing the volume of transfused product, reducing the chances of fluid volume overload. In the case of IMHA where finding compatible blood or simply judging compatibility may be difficult, hemoglobin- based oxygen carrier solution (HBOCS) administration may be beneficial. Decreased production Anemia can result from a reduced production of red cells as well. One cause for reduced red cell production is a decreased level of EPO, leading to reduced erythropoiesis. Patients with chronic renal disease often become anemic as EPO production by the kidneys are diminished. Other factors such as uremic toxins leading to a lowered red cell half-life, hemorrhagic loss due to GI ulcers, increased bleeding tendencies due to platelet dysfunction, inhibition of iron store release, suppression of erythropoiesis by the parathyroid, and reduced nutrient intake may also contribute. Suppression of response to EPO is another cause of reduced production. In the presence of chronic inflammatory disease such as chronic infections, chronic immune conditions, and malignant cancers, or in acute inflammatory diseases, red cell production is reduced. This is attributed to an increased production of hepcidin by hepatocytes during inflammatory disease, which inhibit the iron exporting action of ferroportin in macrophages and enterocytes. This reduces the iron available for erythropoiesis. In addition, inflammatory mediators (tumor necrosis factor-α and interleukin-1) released from leukocytes reduce surface EPO receptors on erythroid stem cells, leading to suppression of erythropoiesis. Dysfunction of the bone marrow may be another cause for reduced RBC production. Irradiation, toxicities, viral or bacterial infections, and administration of certain drugs can result in marrow aplasia, leading to a lack of marrow stem cells. Myelopthisis, or marrow suppression secondary to marrow infiltration by tumors can displace or inhibit production of hematopoietic cells. Both of these situations result in a pancytopenia. In FeLV infections in cats or immune-mediated erythroid stem cell destruction in dogs, erythrocyte precursor cells are specifically reduced in number, leading to red cell aplasia. When nutrients required for producing the signaling system for erythropoiesis and functional erythrocytes are deficient, anemia will occur. Folic acid, vitamin B12, cobalt and intrinsic factor (a glycoprotein aiding in absorption of vitamin B12) deficiency can result in a dysfunction of DNA and RNA synthesis, leading to production of erythrocytes of abnormal shape and size. These abnormal cells are destroyed in the bone marrow, thus never making it into circulation. Administration of drugs that antagonize folate (methotrexate for malignant tumors), inhibit folate metabolism (sulfonamides), and deplete folate concentrations (phenobarbital) are potential causes of malformed erythrocytes. A genetic disorder in Giant , Beagles, and Border Collies involving selective malabsorption of vitamin B12 has been reported and lead to a non-regenerative anemia. A deficiency in iron results in production of erythrocytes with a reduced concentration of Hgb, or lead to delay in red cell production resulting in anemia. Treatment for non-regenerative anemia consists of supportive care while the underlying disease process is treated. Infectious and toxic causes may be alleviated over time, yet neoplastic and genetic causes typically have no complete resolutions. Ineffective erythropoiesis due to nutrient deficiency can be alleviated through supplementation. In the case of decreased EPO levels, such as chronic kidney disease, EPO may be administered to promote erythropoiesis. If the anemia reaches a point of clinical signs of hypoxia, administration of red cell products or HBOC solution may be beneficial.

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CPR: The RECOVER Guidelines Kenichiro Yagi, BS, RVT, VTS (ECC, SAIM) Adobe Animal Hospital Los Altos, CA

In June of 2012, the Reassessment Campaign on Veterinary Resuscitation (RECOVER) published the first evidence based guideline for veterinary cardiopulmonary resuscitation (CPR). The initiative was launched after considering the difference in success rates of CPR between human (20%) and veterinary (6-7%) settings, with the human counterpart having established evidence-based guidelines through the American Heart Association. There are definitely physiologic and anatomic differences between human patients and veterinary patients, but one would expect a comprehensive, evidence-based treatment strategy on execution of CPR to improve the outcome through optimization of the CPR protocols. The RECOVER initiative was carried out through the involvement of over 80 experts from the American College of Veterinary Emergency and Critical Care (ACVECC) and American College of Veterinary Anesthesia (AVTA) of multi-national background evaluating published studies available to answer clinical questions organized into 5 different subtopics to arrive at a consensus guideline. This groundbreaking effort not only produced a guideline that is now utilized all over the world to refine CPR practices, but has also injected fuel into the drive towards evidence-based practices in veterinary medicine, and sparked many other movements in the process.

Evidence in CPR Many clinical questions asked in 5 different “domains” of (1) Preparedness & Prevention, (2) Basic Life Support, (3) Advanced Life Support, (4) Monitoring, and (5) Post-Cardiac Arrest Care were answered to confirm or disprove existing beliefs, provided new knowledge, and also allowed us to identify gaps in the knowledge available to come to definitive answers. The guideline emphasizes importance in early initiation of CPR as a key factor in successful outcome. Preparation for swift intervention when a patient going into cardiac arrest can be accomplished through thorough training of the staff in both didactic (knowledge) and psychomotor (physical) aspects of CPR. CPR drills simulating the arrest and response allows staff members to better understand the sequence of events and potential turns the event may take. Periodic refresher training sessions at least every 6 months is recommended. Preparation of the facility through setup of a crash cart in a central location, which is regularly checked for stock with a detailed checklist will allow for easy access to supplies and equipment required for CPR. Cognitive aides consisting of the CPR algorithm, drug dosage charts, CPR priority checklist should be readily available in the emergency area, with the staff trained on their usage prior to the event, helping adherence to proper protocol. Swift intervention is better made when cardiopulmonary arrest (CPA) is recognized quickly, and CPR initiated. Assessment of the patient for CPA should be performed in no more than 10-15 seconds through a standardized approach. If CPA is even suspected, chest compressions should be started right away since any delay can significantly reduce the chance of success, accurate assessment of a lack of a pulse is difficult without taking a long time, and performing compressions on a patient that is not in CPA brings very little harm. In an inpatient situation, clear identification of patients at risk of CPA to the staff should allow for earlier recognition.

Basic life support CPR starts with provision of basic life support (BLS) as the priority, and most important aspect of CPR. The mnemonic CAB is now used to describe the priority order of circulation, airway, and breathing, because breathing is not helpful in oxygen delivery if circulation of blood has ceased. Evidence points towards delay in initiation of compressions leading to lower success rates in CPR. In regards to compressions, there were no differences seen between right and left lateral recumbency. Chest compressions should be performed to 1/3 to 1/2 of chest width (which takes quite a bit of force for large animals, while moderation may be required for smaller patients) at a rate of 100-120 compressions per minute while allowing full chest recoil in between. The compressions should be focused at the highest point of the chest for dogs with normal conformation, over the heart for keel-chested dogs, and over the sternum in flat-chested dogs (such as some bulldogs). Small dogs and cats should have compressions performed over the heart, and compressions may be performed with a circumferential or two-handed technique. The use of a metronome, songs, or other methods of keeping the rate consistent to recommended rates is useful. Even when compressions are executed properly, it may only produce about 30% of normal cardiac output, which illustrates the need for swift and proper compressions during CPR. Interrupting of compressions significantly reduces the forward flow created through consistent application of compressions, and is best avoided. Compressions should not be stopped to auscultate the heart, check for pulses, assess the patient, or place an endotracheal tube for a full 2 minutes per cycle of compressions. 10-15 seconds in between 2 minute cycles should be used for assessment of the patient, and compressions resumed promptly if no change in CPA is seen. The compressor should be switched between cycles as well, to prevent physical fatigue as 2 minutes of repetitive compressions is physically demanding.

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The airway should be verified to be patent, and any obstructions dislodged. Endotracheal intubation should be performed without interruption of compressions, and ventilations performed approximately at 10mL/kg tidal volume (or 20cmH2O of pressure if no spirometer) at 10 breaths per minute with an inspiratory time of 1 second. Hyperventilation is best avoided to prevent vasoconstriction from low CO2 levels leading to poor cerebral perfusion. Mouth-to-snout ventilation may be used if supplies for endotracheal intubation are not available. In the case of single person CPR, 2 short breaths in between 30 chest compressions is recommended.

Advanced life support With basic life support provided, the attention of the CPR team should be directed to providing advanced life support, including monitoring, drug therapy, and electrical defibrillation. The two forms of monitoring that prove useful during CPR is the electrocardiogram (ECG) and end-tidal carbon dioxide (ETCO2) monitoring. Pulse oximeters and oscillometric or Doppler blood pressure monitoring is not effective in assessment during CPR due to movement and poor perfusion state. The electrocardiogram is also prone to motion artifacts during compressions, making interpretation difficult. Regardless, specific tracings may be seen during or in between compression cycles, guiding therapy. Asystole, pulseless electrical activity (PEA) and ventricular fibrillation (VF) are notable arrhythmias seen in CPR. Capnography, or measurement of CO2 in the breaths coming out of the patient is monitored easily in a patient that is endotracheally intubated. ETCO2 measurement is the most reliable form of monitoring for effective compressions since the level of CO2 measured correlates to the level of perfusion the lungs are receiving, given there is no severe pulmonary pathology. ETCO2 levels higher than 10-15mmHg during CPR was observed to give a higher chance of return of spontaneous circulation (ROSC). Upon ROSC, ETCO2 increases significantly as perfusion to the lungs are re-established, and can be used as an indicator of ROSC. Drugs can be administered intravenously (IV) or intraosseously (IO) during CPR, and access should be established without interruption of compressions. Vasopressors, parasympatholytics, anti-arrhythmics, reversal agents, IV fluids, and alkalinizing agents are used in specific situations during CPR. Vasopressors are indicated for use in CPR regardless of ECG readings to increase systemic vascular resistance and optimizing perfusion through the reduced cardiac output. Epinephrine, an alpha-1, beta-1 and beta-2 adrenergic agonist causes vasoconstriction, and is given at a low does (0.01mg/kg) initially, and at a high dose (0.1mg/kg) with prolonged duration of CPR. Vasopressin is an alternative that may be used in place of epinephrine at 0.8U/kg. Both vasopressors are given every other cycle of compressions due to its half-life. Atropine has traditionally been given as an anticholinergic and a sympatholytic drug. There is minimal evidence indicating benefits of atropine administration during CPR, though there is also no evidence of harm. Atropine is given at 0.04mg/kg IV or IO at the initiation of CPR or as soon as IV or IO access is established, with redosing performed every other cycle of compressions. Anti- arrhythmics may be useful in ventricular fibrillation (VF) that does not respond to electrical defibrillation. Amiodarone at 2.5-5mg/kg IV or IO is recommended, with lidocaine at 2mg/kg slow IV or IO being a secondary option. Reversal of any anesthetic or analgesic drugs seems reasonable though no evidence is seen. Opioids can be reversed with naloxone (0.04mg/kg), benzodiazepines with flumazenil (0.01mg/kg), and alpha-2 agonists with atipamezole (0.1mg/kg) or yohimbine (0.1mg/kg), each IV or IO. Intravenous fluids may be beneficial if the patient is known or is suspected of hypovolemia to help restore intravenous volume and perfusion, but is unlikely to be of any benefit (and may even be detrimental) to those that are euvolemic or hypervolemic. Corticosteroid administration may have been traditionally performed, though evidence suggests more potential harm than benefits, discouraging its use. Sodium bicarbonate administration is considered in patients with prolonged CPA (10-15 minutes) to counter effects of metabolic acidosis which is likely to be present. Electrical defibrillation is useful in patients with VF and has been associated with a higher rate of ROSC. Electrical defibrillation delivers an electrical shock to the heart “resetting” the myocytes and allowing them to resume a more orderly conduction and contraction pattern. Monophasic and biphasic defibrillators are available on the market. Biphasic models are recommended over monophasic because of the higher success rate and less damage caused by a lower current used. Defibrillation should be performed in between compression cycles to minimize interruptions and allow for recharging of the defibrillator should repeated discharges be necessary.

Post-resuscitation care The survival to discharge rate of a patient that successfully achieves ROSC is quite low, reported to be 16% in one veterinary study. The final outcome has a multitude of factors including underlying disease, the cause of CPA, and damage to tissues sustained during and after CPR. Post-resuscitative care is directed towards respiratory optimization performed through monitoring and providing adequate ventilation and oxygenation, hemodynamic support with IV fluids, vasopressors, and inotropes as indicated, and neuroprotective therapy consisting of seizure control, permissive hypothermia, and intracranial pressure control. Optimization of the respiratory, cardiovascular, and nervous systems allows the best chance for patient life to continue while the underlying disease is treated.

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Non-medical aspects Even when patients at risk of CPA are identified ahead of time and the team is prepared with the appropriate facilities to perform CPR, administration of CPR can be quite chaotic. The aim is to bring as much organization and order to the chaos as humanly possible. One of the biggest factors to keeping the order is the organization of a team. There are several roles to be established ahead of time in training for any one person to be comfortably able to fill all roles necessary. The roles needed are: CPR leader, compressor, ventilator, record keeper, drug handler, and the veterinarian. The CPR leader should be identified at the beginning of CPR, so assigning of subsequent tasks can begin immediately. Staffing permitting, the CPR lead should be freed from tasks aside from assigning and keeping the team organized. Compressor and ventilators provide the compression and ventilation, and may make sense to alternate with each other between compression cycles if staffing is limited. The record keeper should keep a detailed medical record during CPR, and this task is facilitated with a CPR record form. The drug handler will prepare and administer drugs in most cases. The veterinarian ideally is not fulfilling any of these roles, being able to focus on the patient and making judgments on whether CPR efforts should continue, decisions on drug administration, communication with the owners, and any medical interventions that are necessary for the patient. Communication during CPR is also vital to inn organizing the effort and preventing mistakes. Closed-loop communication, performed through the person making a request addressing an individual clearly by name, the addressed individual repeating back their understanding of the request, the request being fulfilled being announced, and the requestor acknowledging the completion. Keeping the communication loops closed each time may feel awkward if it is not used on a regular basis, but contributes to very organized communication allowing everyone on the scene to stay on the same page on the status of the CPR. Double checking each other on tasks being performed is also possible, preventing the preventable mistakes. Debriefing is another form of communication that is hugely beneficial for the team, regardless of the outcome. After the conclusion of CPR, every member should participate in a 5-15 minute debriefing session discussing the CPR. The discussion will be lead by the CPR lead, discussing the following points: 1. What went well with this CPR session? 2. What could we have done differently? 3. Are there any goals we can set for ourselves for future CPR sessions? 4. Are there any serious concerns you would like to bring up? Debriefing sessions will bring your team even closer together as a functional unit. This also provides opportunities for staff members to express any stress they may have faced in a productive and constructive manner, and a chance for better understanding of the event that passed. Debriefing is intended for us to be able to think towards bettering our effectiveness in CPR, providing each individual patient the best possible chance of recovery and positive outcome. Bring your open mind, active listening, and participation to each of these debriefings. Commend each other on what was done well, regardless of the outcome. Discuss what could be done differently to perform CPR better. Every opinion is important, and should be discussed in a professional manner. Being open in communication requires trust and willingness to give and take feedback without bias and being personally affected.

Has RECOVER made a difference? In the first year since the implementation of the RECOVER guideline into our CPR training protocol, a total of 54 CPR efforts (35 dogs,18 cats, 1 chinchilla) have been made at the author’s practice (data collection for the second year is ongoing). The average age was 9 years old, with variable reasons. The average duration of CPR was 11 minutes, with the shortest effort lasting 1 minute and the longest 32 consecutive minutes (one effort lasted 47 minutes total, with intermittent ROSC). The ROSC rate was 24.1% (13 of 54), with a survival-to-discharge rate of 3.7% (2 of 54). The average duration of CPR effort achieving ROSC was 9.5 minutes (high: 27, low 1). One of the patients who were eventually discharged was suspected to have experienced hyperkalemia related cardiac arrest from urinary obstruction, while the other was suspected to have suffered from severe metabolic acidosis and potential over- supplementation of potassium as insulin doses were reduced without a change in KCl content of IV fluids (diabetic ketoacidosis patient). Comparison with previously published statistics unfortunately does not yield a significant difference at our practice. The staff, however, feels better prepared for the ultimate emergency, and feels confident the best chances are provided for each of our patients.

Other effects of RECOVER RECOVER has brought on some indirect changes to the veterinary field in addition to providing standardization of CPR protocols. The Academy of Veterinary Emergency and Critical Care Technicians (AVECCT) is in the process of using similar evidence grading methods used by the RECOVER initiative in creating evidence-based nursing guidelines, inspired by the initiative. Evidence-based veterinary medicine (EVBM) has gained significant momentum since RECOVER guidelines were published, and while this could be temporally a coincidence, there is no denying the initiative adds significant weight to the importance of EVBM. ACVECC is now offering a college sanctioned veterinary CPR BLS training program through Veritas, offering certification for both didactic and psychomotor training. The training program, in the long term is anticipated to reach the public. As the immediate next steps, an 956

advance life support course is being designed, and a trainer certification program is also in the works. Advancement in the field of veterinary emergency and critical care has been accelerated due to the RECOVER initiative.

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Just Breathe! Respiratory Emergencies Kenichiro Yagi, BS, RVT, VTS (ECC, SAIM) Adobe Animal Hospital Los Altos, CA

Respiratory distress is a very common form of emergency in veterinary medicine. The primary role of the respiratory system is to oxygenate and control CO2 levels in the blood. Inability for patients to properly oxygenate blood and saturate hemoglobin (hypoxemia) will lead to inadequate delivery of oxygen to the tissues (hypoxia). In a hypoxic state, cellular energy production is shifted primarily to anaerobic metabolism, resulting in lactic acid buildup and acidemia (metabolic acidosis). In addition, insufficient alveolar ventilation will lead to an elevation in the arterial CO2 level, or hypercapnia. Hypercapnia leads to respiratory acidosis, decreases cardiac contractility, and depresses diaphragmatic function. Both of hypoxemia and hypercapnia, when allowed to persist, will lead to the demise of a patient and swift assessment of respiratory compromise is required for appropriate treatment.

Initial assessment and treatments Assessment of a patient starts with external physical signs. Patients presenting with signs such as tachypnea, increased respiratory effort, and open-mouth breathing are clearly in trouble. Exaggerated movement of parts of the body surrounding the physical construct of the airway such as flaring nostrils, lip movement with respiration, sucking in and out of the skin under the chin and thoracic inlets, and paradoxical abdominal movement are all signs of significant effort. An orthopneic position, characterized by open-mouth breathing, extending of the head and neck, sitting up sternal, and abduction of the elbows in the effort to open up the airway as much as possible, is another external sign of respiratory distress. If the patient progresses to being unable to hold themselves up, going into lateral recumbency with no improvement in respiratory signs, the patient may be experiencing fatigue and facing imminent arrest. Assessment and treatment of a patient in respiratory distress poses a dilemma, as swift determination of the patient’s problem is required, yet they may be compromised such that the stress of diagnostics and treatment may push them into respiratory and cardiac arrest. These patients are in a very fragile state, and initial efforts are aimed at improving the patient’s ability to breathe while minimizing stress and deterioration in respiratory status. Providing oxygen supplementation through flow-by, mask, induction chamber, or cage would be one of the first lines of therapy to alleviate distress. Patients in respiratory distress are often very anxious, which often makes the patient even more dyspneic. A light sedation with small doses of benign sedative such as butorphanol may be beneficial to help ease anxiety. The staff working on the patient should conduct themselves in a calm and quiet manner yet maintaining swiftness. A calmer environment will not only benefit the patient, but may benefit a worried owner. The presence of the owner can either be beneficial or detrimental to the patient, and staff directing attention to calming a panicked client (and successfully doing so) may also help the patient. Diagnostics and treatment such as physical examination, radiographs, blood work and IV catheterization may have to be held off until the patient is more relaxed and breathing better. Evaluation of a patient’s respiratory problem begins with external visualization of their breaths. The manner in which a patient breathes is adapted to the method requiring the least work of breathing. An obstructive breathing pattern, involving a prolonged inspiration (upper airway) or expiration (intrathoracic lower airways), will be observed in patients with narrowed airways. A restrictive breathing pattern, involving shallower but tachypneic breathing, will be observed in pleural disease or reduction of lung compliance. Abdominal effort may be seen with patients with compromised lungs. Certain conditions (anemia, metabolic acidosis, and pain, for example) can cause “non-respiratory look-alikes”. Auscultation is a valuable skill in early detection and detection of change in lung states. Stertor (snoring), wheezes (whistling), and stridor (high pitched noise) can indicate different upper airway issues. Crackles indicate fluid in the alveoli, such as in pneumonia or pulmonary edema. The location lung sounds are present or absent in helps indicate causes as well. Cardiogenic pulmonary edema often begins near the heart (perihilar region), and aspiration pneumonia often originate in the cranioventral lobes. Absence or decrease in lung sounds in the caudal and ventral fields may indicate pleural effusion, while dorsal fields may be due to . While abnormalities in auscultations do not lead to a diagnosis, it serves as an indication for further diagnostics. If a pleural space issue like pleural effusion of pneumothorax is suspected, performing thoracocentesis to evacuate the fluid or air can provide diagnostic information and therapeutic treatment simultaneously. The staff should be prepared to perform endotracheal intubation and provide positive pressure ventilation (PPV) if the patient does not stabilize with initial treatment and deteriorates.

Types of respiratory emergencies Upper airway problems Upper airway issues leading to respiratory distress are common in veterinary medicine, and can involve various causes. Laryngeal paralysis is common in older, larger breed dogs, with a higher prevalence in males. A loss in innervation of the cricoarytenoideus dorsalis muscle leads to atrophy, preventing the arytenoid cartilage from being abducted. The laryngeal opening is narrowed, leading to an increase in airway resistance. Causes may be congenital or from trauma, neuromuscular disease, neoplasia, hypothyroidism, or 958

idiopathic. Affected dogs exhibit inspiratory stridor, exercise intolerance, ptyalism, and a change in their bark. Laryngeal paralysis can cause severe respiratory distress and collapse depending on severity. Emergency stabilization involves endotracheal intubation. Once stabilized, medical management may be possible with the goals of minimizing stress, excitement, and exposure to high environmental temperature. Surgical treatment is most effective, involving unilateral lateralization of the arytenoid cartilage, or laryngeal tie-back. Chances of aspiration pneumonia are increased in dogs undergoing this procedure. Cats rarely present with laryngeal paralysis, though a study suggests laryngeal paralysis a differential for cats with dyspnea, inspiratory stridor, coughing/gagging, or a change in voice, with complete resolution through unilateral lateralization. Brachycephalic syndrome results from anatomical abnormalities seen in brachycephalic breeds leading to upper airway narrowing or obstruction. Stenotic nares, enlarged tonsils, and elongated soft palate require the breed to create larger negative pressure to breath normally, creating a narrowed airway from hyperplasia of the airway beyond the nares. A further increase in negative pressure may evert laryngeal saccules and collapse the larynx or trachea. Pulling of air through the narrowed airways can further cause inflammation and edema, placing the patient in further respiratory dysfunction. Surgical intervention through widening of the nares, resection of the palate and everted laryngeal saccules, and removing the tonsils is the recommended treatment. In addition, upper airway obstruction may occur due to lodging of a foreign body, neoplasia, or the formation of nasopharyngeal polyps. Any upper airway dysfunction or obstruction can lead a patient to present with respiratory distress. Secondary complications such as non-cardiogenic pulmonary edema, heat stroke, and aspiration pneumonia may be seen. Pulmonary edema is a common cause of respiratory distress in dogs and cats. Accumulation of extravascular fluid occurs in the alveoli and pulmonary parenchyma due to increased hydrostatic pressure or increased permeability in the pulmonary vasculature. Patients present with respiratory distress and have poor oxygenation. The reduced oxygenation is due to a ventilation-perfusion mismatch (V/Q mismatch) because the presence of fluid in the alveoli leads to compromised ventilation. Left sided heart failure can lead to pulmonary hypertension, causing cardiogenic pulmonary edema. In cardiac disease, fluid retention and an increase in blood volume is seen as a compensatory mechanism for lowered cardiac ouput. The chronic increase in blood volume leads to an increased hydrostatic pressure (because of congestion) in the pulmonary vasculature, resulting in pulmonary edema. Patient with cardiogenic pulmonary edema may show signs of coughing, exercise intolerance, and may have a heart murmur. An echocardiogram may be performed to confirm cardiac disease and pulmonary hypertension. Fluid volume overload through fluid therapy is a possible cause of cardiogenic pulmonary edema, especially in patients with cardiac or kidney disease. Both cardiac and kidney disease can be asymptomatic, so patients on fluid therapy should be closely monitored for signs of fluid overload. Non-cardiogenic pulmonary edema can occur from increased permeability within the lung tissue through damage to the microvasculature or alveolar epithelium. Electrocution, seizures, strangulation, pulmonary thromboembolism, and chemical exposure are all potential causes. Illnesses associated with systemic vasculitis such as sepsis and systemic inflammatory response syndrome (SIRS) are also associated with non-cardiogenic pulmonary edema. Patients with pulmonary edema are treated with oxygen to alleviate hypoxemia. Patients that are unable to maintain an arterial partial pressure of oxygen (PaO2) greater than 60mmHg despite oxygen therapy may require endotracheal intubation and PPV. An arterial blood sample and a blood gas analyzer are required to obtain a PaO2 measurement. Placement of an arterial catheter is beneficial in serial monitoring of PaO2. PPV is also indicated if the arterial partial pressure of CO2 (PaCO2) is greater than 60mmHg. A venous sample is acceptable in measuring CO2 levels (PvCO2 for venous) and is typically within 5mmHg from arterial values. Some patients may have a positional “preference” in their ability to oxygenate and ventilate, with sternal recumbency usually being most beneficial. Medical management of the cause of pulmonary edema is warranted in conjunction with respiratory support. Diuretics are administered to reduce pulmonary capillary pressure and reduce preload through reduction of blood volume. Furosemide is a commonly used diuretic due to its rapid onset. In addition to its diuretic effect, furosemide may have further beneficial effects of pulmonary vasodilation and bronchodilation. Hemoconcentration resulting from reduced intravascular volume increases the plasma colloid osmotic pressure, helping the removal of fluid from the alveoli. Nitroprusside and glycerol trinitrate are vasoldilators that may be used as an additional method in reducing hydrostatic pressure. Bronchodilators such as terbutaline may also be used, and fluid therapy restricted. Chances of resolution depend heavily on the cause, and treatment for the patient’s specific underlying disease is required. Pleural space disease When the pleural space which normally serves to create negative intrathoracic pressure during breathing is filled with material which normally do not exist, normal breathing is compromised. The material may be various types of fluid, air, or even organs. The pleural space being occupied by these abnormal substances will cause the lunges to collapse and prevent adequate inflation, leading to a decrease in tidal volume, total vital capacity, and functional residual capacity. The lung volumes lead to hypoventilation, which can result in hypoxemia and hypercapnia. Accumulation of fluid in the pleural space is called pleural effusion and can be of various type. Hydrothorax, or accumulation of transudate can be a result of reduced plasma colloid osmotic pressure, increased hydrostatic pressure, increased vascular permeability,

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or neoplasia. Transudate is defined as effusion containing TP < 2.5g/dl and total nucleated cell count (TNCC) < 1500/µl. Effusion with TP between 2.5 and 7.5 g/dl and TNCC between 1000-7000/µl is considered to be modified transudate. Effusion with TP > 3.0g/dl and TNCC > 7000/µl is defined to be exudate. Feline infectious peritonitis (FIP), caused by a coronavirus can cause exudative or modified transudate effusion with yellow to straw-colored, viscous fluid with a high protein but low TNCC. Pyothorax is an accumulation of purulent exudate in the pleural space. Causes include bacterial infection due to migrating inhaled foreign objects, penetrating trauma to the chest wall, pneumonia, migrating plant material, and iatrogenic causes. Patients with pyothorax are typically treated with supportive care, antimicrobial therapy, and chest tube placement for intermittent lavaging with physiologic saline. In some cases, surgical exploration of the chest cavity to remove the source of the infection may be chosen. Accumulation of pink or white, milky, chylous effusion is termed . The opaqueness is a result of a high triglyceride concentration. Potential causes include cardiomyopathy, congestive heart failure, pericardial disease, thoracic duct obstruction or rupture, lymphosarcoma, thymoma, and lung lobe torsion. Patients with chylothorax are typically managed by removal of the effusion through thoracocentesis. Hemothorax can result from coagulopathy, trauma, neoplasia, lung lobe torsion, pulmonary thromboembolism, and thymic hemorrhage. Iagtrogenic causes are also possible, from procedures such as thoracocentesis, thoracostomy, and intrathoracic biopsy. An open pneumothorax can result from penetrating thoracic trauma. Closed pneumothorax can occur due to damaged lung parenchyma, trachea, airway, esophagus, mediastinum, or diaphragm. Traumatic pneumothorax is the most common type of pneumothorax, caused by blunt force trauma such as automobile accidents or falling from heights. Gradual accumulation of air and pressure due to the lesion acting as a one-way valve results in a tension pneumothorax. A tension pneumothorax is life-threatening; increased intrathoracic pressure causes cardiovascular depression through reduction of venous return, leading to shock. Immediate thoracocentesis, and in persistent tension pneumothorax, a thoracostomy tube may be placed to continuously evacuate air out of the chest cavity. This is accomplished with a continuous suction device, or a one way valve. The patient is monitored for subsequent occurrences of dyspnea, indicating a return of pneumothorax. If a closed pneumothorax does not resolve in 3-5 days, surgical exploratory is warranted. Diaphragmatic hernia may occur due to trauma or could be congenital. The degree of dyspnea varies depending on the degree of herniation, presence of concurrent pleural effusion, and presence of thoracic injuries. Surgical treatment is warranted when diaphragmatic hernias are seen, and should be performed immediately if any organ torsion or strangulation is suspected. Prognosis is good in patients receiving surgical intervention within 24 hours. Pneumonia is the inflammation of the pulmonary parenchyma caused typically by an infectious agent which enters the airway. Aspiration pneumonia is caused by inhalation of contaminated material leading to an infection. Patients with aspiration pneumonia may present in respiratory distress and exhibit signs like coughing, weakness and collapse, pyrexia, cyanosis, and purulent nasal discharge. Lung sounds will be loud, and crackles may be heard. Abnormal sounds more often than not can be localized in the cranioventral areas. Treatment will consist of antimicrobial therapy, oxygen therapy and mechanical ventilation if necessary. Nursing interventions such a nebulization and coupaging may be instituted, though human evidence relating to a faster recovery from pneumonia has not been seen.

Patient monitoring During the treatment of patients with respiratory compromise, the patient should be closely monitored on three different aspects; oxygenation, ventilation (carbon dioxide elimination), and the degree of respiratory effort. In addition to the visible respiratory effort and auscultation, different instrumentation and blood analysis can give insight to the progression of the patient’s recovery. Oxygenation A physical sign seen in patients with severe hypoxemia is cyanosis, or a blue color to the mucous membranes. Cyanosis becomes apparent when there is more than 5 g/dL of deoxyhemoglobin present in the blood. An average hemoglobin level in dogs is approximately 13-17 g/dL, and in cats is approximately 10-14 g/dL. This means the oxygen saturation of hemoglobin will be a significantly decreased level on average of 61-70% for dogs and 50-64% for a cat before cyanosis is seen. Patients presenting with cyanosis is severely compromised in their DO2 and requires immediate attention. Oxygenation can be better gauged through measurement of PaO2, serving as an indicator of pulmonary function measured through arterial blood gas analysis. A patient with normal respiratory function breathing room air will have a PaO2 of 80-100mmHg. PaO2 of less than 80mmHg qualifies as hypoxemia, and less than 60mmHg is considered severe hypoxemia. Pulse oximetry allows non-invasive measurements of the percentage of oxygenated functional hemoglobin in the arterial bloodstream. The saturation of oxygen measured by pulse oximetry (SpO2) closely reflects SaO2 and can be used to estimate the PaO2 level. The oxygen-hemoglobin dissociation curve expresses the relationship between SaO2 and PaO2. A SaO2 of 95-98% corresponds to a PaO2 of 80-100mmHg. A SaO2 below 90% indicates a PaO2 of less than 60mmHg. Pulse oximetry has its limitations, including false reading in the presence of significant levels of dysfunctional hemoglobin species (methemoglobin, carboxyhemoglobin), inconsistent readings with movement, poor perfusion, anemia, and pigmented skin. Interpretation of

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oxygenation and pulmonary function can performed by calculated values called the PaO2:FiO2 Ratio (PF ratio) and alveolar-arterial (A-a) gradient. Carbon dioxide elimination CO2 is a metabolic byproduct of energy production. The body normally maintains control of CO2 levels to control the pH level of the body. An accumulation of CO2 causes an increase in levels of carbonic acid, increasing the levels of dissociated hydrogen ions, resulting in an acidic environment. A reduction in CO2 level will lead to a decrease in hydrogen ions, leading to a more basic environment. This effect is called respiratory acidosis and respiratory alkalosis, respectively. The amount of CO2 eliminated by the body depends on the movement of air in and out of the alveoli to perform gas exchange, or ventilation. Room air contains about 0.04% CO2 (0.3mmHg), and the replacement alveolar gas with fresh room air will promote diffusion of CO2 out of the blood stream into the alveoli, which in turn gets expired out of the lungs and airway. A normal CO2 levels within the blood is approximately 35-45mmHg in dogs, and 30-40mmHg in cats, and can be measured by blood gas analysis (PaCO2 if arterial or PvCO2 if venous). The difference in PCO2 in the pulmonary capillaries and alveoli create a pressure gradient required for gas exchange (high to low; high in the capillary, low in the alveoli). PCO2 is largely influenced by the amount of air that can be moved in and out of the alveoli, or alveolar ventilation. Reduced ventilation leading to high PCO2 is called hypoventilation (>45mmHg) and occurs in cases of respiratory depression (suppression of respiration due to drugs, neuromuscular disease, CNS disease), inability to expand the lungs (pleural space disease, compromise to chest walls), or increased resistance to breathing (narrowed airway). Hyperventilation and subsequent low PaCO2 can be seen in patients with increased RR due to anemia and hypoxia. In metabolic acidosis, compensatory increase in respiratory effort and hyperventilation is often seen, countering the metabolic acidosis effect with respiratory alkalosis. This occurs because the presence of hydrogen ions will stimulate the respiratory center of the brain to increase respiratory efforts. The PaCO2 can be estimated by measurement of End-tidal CO2 (ETCO2). The CO2 content in the gas present at the probe at the end of expiration is measured to obtain this value. The ETCO2 in normal cardiovascular and respiratory situation, is within 5mmHg of the PaCO2. The ETCO2 is most easily measured when an endotracheal tube is placed in a patient (anesthetic procedure or mechanically ventilated patients, for example). There are nasal tubes and masks available allowing for less invasive ETCO2 measurement.

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Place that Lifeline! Advanced Vascular Access Kenichiro Yagi, BS, RVT, VTS (ECC, SAIM) Adobe Animal Hospital Los Altos, CA

Vascular access is a critical element in providing treatment for patients presenting in an emergency and requiring continued care during hospitalization. Fluid and infusions, drug administration, and blood sampling are a few key functions different methods in vascular access can serve. Placement of short term peripheral catheters are commonplace in veterinary care even outside of emergency and critical care. There are additional methods in providing vascular access such as placement, intraosseous catheterization, and arterial catheterization, each presenting their own advantages and disadvantages while serving their purpose.

Peripheral venous catheters Peripheral catheterization is commonly performed in everyday veterinary practice, whether it is to administer IV fluids or an avenue for IV injections used for induction of anesthesia. Any catheter that is placed in the periphery that is too short to reach a central vessel is considered a peripheral catheter. Some of the major advantages to using a peripheral catheter includes the ease of placement, minimal discomfort to the patient, and the inexpensive nature of the catheters themselves. In addition, they can be placed quite rapidly with relatively minimal restraint, reducing the stress on the patient. In comparison to central venous catheters, peripheral catheters are less likely to cause complications such as hemorrhaging, thrombosis, and catheter induced infections. Commonly used location of insertion are the cephalic vein, saphenous vein, and more rarely, pedal, auricular, and jugular veins. There is a common misunderstanding that a jugular catheter is by default a central line, though this is not necessarily true since whether a catheter is considered central or not is based on the position of the tip of the catheter. The cephalic vein is catheterized with ease in most patients, as the vein is easily visualized and remains straight for the length of the limb. There are, of course patients with short limbs making catheterization difficult, but this is likely true for all other sites available on such a patient. The saphenous vein can be an alternative catheterization location, though catheters placed in this location are more prone to occlusion through patient positioning. Pedal veins are viable options for larger dogs, though the degree of discomfort seems to be greater. Auricular veins can be more accessible for patients with short limbs, though stabilizing the catheter after placement is often a challenge. Peripheral catheters are most often placed percutaneously with the vein visualized and/or palpated for the location. In cases of the skin seemingly too tough for dry or smooth insertion, or if fraying of the catheter has occurred, creating a relief hole with a separate needle and placing the catheter through the hole is appropriate. In some emergency situations, the vein may not be visible or palpable, in which case a cutdown can be opted to be performed. A venous cutdown involves creating an incision over the anatomic location of the vessel to visualize the vein directly. When a catheter is placed through cutdown, suturing of the incision as well as bandaging of the catheter site is necessary. While a simple task that is routinely performed, there are several complications associated peripheral venous catheters. The first of which is phlebitis, or the inflammation of the vascular walls, causing inflammation of the vessel and surrounding tissues. A patient suffering from phlebitis will show redness, swelling, and pain on palpation. Phlebitis can be caused by mechanical damage if the catheter moves around, infection through the insertion site, or through irritation from injection of hyperosmolar fluids (high concentration dextrose, propylene glycol based drugs, etc). When evidence of phlebitis is seen, the catheter is recommended to be replaced in a different location. Thrombosis, or formation of clots, around the catheter insertion site can also occur, which impedes normal blood flow. Another common complication is subcutaneous fluid infiltration which occur due to the catheter being outside of the vein, leading to infusion of fluid under the skin. This could be from improper placement of the catheter to begin with, or the catheter pulling out of the vein with skin movement. Infection of the catheter insertion site can also occur. Lastly, catheter embolism, or fragmentation of the catheter and subsequent embolism can occur either from a faulty catheter, catheter damage from the stylette, or accidental cutting when the tape is being cut. Because these complications can occur, regular maintenance of the catheter insertion site is warranted. A typical protocol calls for inspection of the insertion site every 24-48 hours, and whenever complications are suspected. Whenever a complication is suspected, the catheter should be replaced. Routine replacement of IV catheters after 72-96 hours has not been shown to be beneficial in preventing phlebitis or catheter induced blood stream infections, and replacement should be based on clinical signs of complications.

Central venous catheters In contrast to peripheral venous catheters, central venous catheters have their most distal end terminate in a central vessel within the chest cavity (cranial or caudal vena cava). Central venous catheters can be inserted through the jugular vein, or be inserted peripherally through the saphenous vein (given you have the correct length catheter to reach the vena cava).

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Central venous catheters are preferred over peripheral venous catheters when the patient requires infusion of highly osmolar fluid (high concentration dextrose, parenteral nutrition solution, for example), or infusion of multiple incompatible fluids are desired (a multi-lumen catheter will be used in this case). Additional function of central venous catheters include measurement of central venous pressure, sampling of central venous blood tests, serving as a sampling catheter, long term venous access, and prevention of contamination by substances that can commonly contaminate peripheral catheters (vomitus, diarrhea, drainage/discharge). Various types of central venous catheters exist. They may be through-the-needle or over-the-needle, and single-lumen or multi- lumen. In general, over-the-needle catheters are preferred as there is no hardware left on the catheter assembly that requires maneuvering during the wrapping. Multi-lumen catheters are generally preferred over single-lumen catheters as it adds flexibility in fluid administration, giving the ability to infuse multiple solutions simultaneously without worries of incompatibility. If the effort and discomfort to the patient in placing a central venous catheter is already being made, giving ourselves the option of utilizing a multi- lumen catheter is a sound decision, as the patient is likely to require multiple infusions, and the cost between a single-lumen and multi- lumen catheter is small. A commonly used technique in the placement of a central venous catheter is called the , or the guidewire technique. A typical protocol and steps involved in the placement of a central line is provided (Figure 1). The Seldinger technique is advantageous because it allows for a smaller catheter to serve as the introducing catheter, making placement in smaller patients or hypovolemic patients easier. In addition, the guidewire can be utilized when a catheter needs to be replaced by refeeding a sterile guidewire through the catheter, allowing a new catheter to be guided back into the vessel. Similar complications to those in peripheral venous catheters can occur with central venous catheters. Due to its invasiveness, the catheter is more prone to blood stream infections, and an appropriate maintenance protocol (examination of insertion site once every 24-48 hours) is required.

Intraosseous catheterization Intraosseous (IO) catheters, are needles or cannulas inserted into the bone marrow. The marrow vessels, unlike peripheral vessels, do not collapse due to the protective osseous coating it has as a part of the structure of the bone marrow. This makes the bone marrow an effective avenue for fluid and drug administration even during circulatory collapse. The effectiveness of blood components and crystalloids is equal to central or peripheral venous access. Some drugs and fluids may have a higher duration of action and peak effect when given IO during shock, though onset of peak effect may be slower without pressurized infusion. When IV access is difficult or taking longer than a few minutes, an IO catheter should be considered, and included as a part of a standard fluid resuscitation protocol. An IO catheter is often placed in under a minute, at a very high success rate. Once an IO catheter is placed and fluids given to provide better vascular volume, another attempt at IV access should be more likely to be successful. Other situations which make IV access extremely difficult, such as peripheral edema, obesity, status epilepticus, and generalized burns may be other indications for IO access. Blood values obtained from IO catheters are found to be comparable to central or peripheral venous samples, aside from potassium, glucose, and acid/base values. IO catheter placement is contraindicated when fractures are present in the bone. This, along with previous IO catheter placement in the same bone, can lead to extravasation of infusions. In the case of previous IO catheterization, a larger size needle may be inserted in the same hole effectively plugging the existing catheterization site. Use of a completely different bone is also a solution. Placement of IO catheters through infected tissue, or in pneumatic bone in avian species should be avoided. Any sterile needle long enough and sturdy enough to bore through the cortex and easily contained by the marrow of a specific patient is suitable. 18-22ga needles are often used for rodents, neonates, and even adult cats, small breed dogs. Bone biopsy needles are used in adult cats and dogs. IO catheter drills and catheter guns are contraptions to aid IO placement. Considerations to make regarding the catheterization site include ease of access and placement, possibility of interference in procedures, and patient comfort (though not a major concern during an emergency situation). No site is shown to be better than the other in terms of efficacy of infusions. The viable sites are (1) Tibia – Medial surface of proximal tibia, tibial tuberosity (point slightly distally to avoid growth plate, which is a major longitudinal growth front for the tibia) (2)Femur – Trochanteric fossa (3) Humerus – Greater tubercle (4) Hips – Wing of ilium, ischium. Any angle of insertion is acceptable as long as the needle tip is within the marrow, though certain angles of approach may be easier for different sites. Advancing the needle through subcutaneous tissue and periosteum may be painful. In stable patients, subcutaneous lidocaine block may be used to attempt to prevent pain. Many patients requiring immediate IV/IO access will likely have altered mentation preventing them from feeling or responding to pain. In these situations, the speed of placement will be prioritized over initial pain control. The pressure build up when an infusion is started is known to cause pain in people. The same is assumed for non-human species. Removing a small amount of marrow, and infusing lidocaine over a minute or so will help alleviate this initial pain. Once again, this is likely not our primary concern in cases where seconds to minutes matter in the resuscitation of the patient.

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Chances of complications with IO catheters are low, but present. Infection are rare, especially when the catheter is removed as soon as it is unnecessary. Extravasation of fluids, compartment syndrome (pressure buildup damaging muscle, nerve, blood vessels), bone fracture, and fat embolism (unknown clinical significance) are among other complications that might arise.

Figure 1: Central venous catheter placement Central line placement Equipment needed  Guide-wire catheter kit  Suture  Needle Holder  Thumb forceps  Clippers  Surgical scrub  Sterile gloves  Drape  #11 blade or large needle  Sterile gauze  Heparinized saline flushes  Bandage material  X-ray request Preparation  Determine if sedation is required, and administer prior to gathering of supplies to allow time. If transdermal analgesic cream is to be used, clip and apply first.  Clip area over the jugular, 2-4 inches by 2-4 inches depending on patient size.  Pre-measure the distance from the intended insertion site to the 4th intercostal space.  Aseptically prep the area in a circular, surgical scrub motion. Procedure 1. Wash hands and don sterile gloves. 2. Drape the prepared area. 3. Place the over-the-needle catheter included in the kit into the vein, oriented towards the heart. (Note: in some cases, you will not see a flash in your stylet hub, in which case check with syringe) 4. Insert the guidewire into the catheter and feed forward to the premeasured length. 5. Remove the catheter over the guidewire, taking care to not contaminate the guidewire. 6. Place the plastic dilator over the guidewire, and insert into the vessel through the skin. Tenting the skin, spinning the dilator, and creating a relief hole will help facilitate the dilation process. 7. Remove the dilator over the guidewire after leaving in the vessel for a few seconds. 8. Place the catheter over the guidewire and feed into the dilated opening into the vessel. Be sure to observe the guidewire exiting out the catheter port and hold it in place to prevent loss of the wire. 9. Once the catheter is fed to the pre-measured length, remove the guidewire. 10. Aspirate port with a syringe to confirm blood flow, then flush with heparinized saline. Attach needleless ports. Repeat for each port to confirm patency. (Note: Aspirating first prevent injection of air). 11. Secure the catheter with suture using the suture wing(s). 12. Cover the insertion site with non-stick gauze pad or adhesive dressing, and bandage.

Placement procedures After the site is chosen: 1. The hair on the potential insertion site should be clipped and the area disinfected. Be mindful of the balance of the time you have versus the time it takes for a thorough scrubbing. 2. A stab incision can be made to allow for easier access to the insertion site. 3. Firm and steady pressure should be applied to the bone with an alternating clockwise and counterclockwise rotation (being careful not to slip on the bone surface). 4. Once the initial hole is started with the needle, the pressure can be increased as the same motion is made, to bore faster through the cortex. 5. When the needle pushes through the cortex, a sudden loss of resistance will be felt. 6. Proper placement of the catheter can be confirmed in a few ways: a. Firmness of the catheter insertion – There will be very little wiggle in the needle when properly inserted through cortex. b. Movement with the limb – Catheters in the cortex will make the same movement as the bone it is inserted in. If the catheter moves independently of the bone, or vice versa, the catheter is likely placed improperly. c. Aspiration – Bone marrow should be able to be aspirated in a properly placed catheter, though this is less likely to occur in an older animal.

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d. Saline Infusion – If placed correctly, saline should be able to be pushed without much resistance. If a large backpressure is encountered, the needle is likely to be in the cortex, or pushed against it. Rotation of the needle 90-180 degrees may alleviate this if the needle opening is simply pushed up against cortex. If the infusion results in subcutaneous elevation of tissue (subcutaneous “bleb”), the catheter is improperly placed. 7. Once proper placement is confirmed, the catheter is stabilized via tape or suture on tape wings. Some IO catheters will come with suture wings. 8. Proper catheter care is required with bandages applied when possible. A properly maintained IO catheter may be kept for 72hours with minimal chance of complications. Typically, IO catheters are replaced by IV catheters within 2-12 hours after initial fluid resuscitation.

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The Bloody Truths: Myths and Facts of Transfusion Medicine Kenichiro Yagi, BS, RVT, VTS (ECC, SAIM) Adobe Animal Hospital Los Altos, CA

Despite the increase in use of blood products and transfusion therapy becoming more commonplace, there are many questions surrounding their use. Many of these questions are being answered by a combination of emerging veterinary and human evidence further clarifying already known concepts, with others confirming long time suspicions and teaching us something new.

Can RBCs be given through an ? Whether there is an optimal method of red blood cell transfusion administration has been a point of discussion. Recommendations from infusion pump manufacturers are variable in ability to transfuse blood products. The criteria used to make these recommendations are also uncertain without an established standard or regulatory body in validating these claims. An ideal method of administration should allow one to administer the red cells at a consistent and specified rate while not affecting the integrity, survival time, and oxygen carrying capacity of the red blood cells. Studies evaluating the effect of various administration methods on the integrity of blood cells exist. The majority of these studies investigate the in vitro effect of infusion pumps, measuring the degree of free RBC content (free hemoglobin, potassium, lactate dehydrogenase, bilirubin) and osmotic fragility. The results vary from observing significant increases to insignificant increase in values, while transfusions with red cells with longer storage time resulting in a larger increase of hemolysis markers than those with shorter storage times. The variability in results, in addition to the anecdotal evidence of patients benefiting from RBC transfusions administered with infusion pumps are a cause for varying opinions. A study assessing in vivo survival time of RBCs infused with various infusion methods, compared the use of gravity flow, volumetric peristaltic pump, and syringe pump in autologous transfusions in dogs. Blood was collected from 9 healthy dogs, washed, and separated into 3 portions labeled with different densities of biotin. These labeled red cells were transfused through either gravity flow with a 170-260 µm filter, volumetric peristaltic infusion pump with a 170-260 µm filter, or a syringe infusion pump with an 18 µm aggregate filter at 2mL/kg/hr. Blood was sampled from test subjects at day 1, and every 7 days until day 49, measuring the proportion of red cells with biotin labels through flow cytometry. Additional in vitro testing was conducted, measuring plasma hemoglobin and osmotic fragility testing. Labeled RBCs infused through gravity flow, volumetric pump, and syringe pump were detectable in 100% (8/8), 50% (4/8), and 14.3% (1/7) samples, respectively post-transfusion. The quantity and half-life between RBCs infused by gravity flow and volumetric pump that were detectable (4/8) were not different. The RBCs infused via syringe pump detected at 24 hours post transfusion was no longer detectable at 7 days, indicating complete removal of those cells from circulation sometime between 24 hours and 7 days post transfusion. There were no differences seen in in vitro values examined. The study concluded that delivery of RBCs with a syringe pump and microaggregate filter is associated with significant decrease in in vivo survival time. Volumetric pump delivery was associated with a 50% probability of loss of transfused RBCs within the first 24 hours, and gravity flow allowed for highest chance of RBC survival. The reason behind this difference is speculated to be the mechanical shear damage to the RBC membranes when transfused through the microaggregate filter, causing preferential removal of damaged cells upon entry into the circulation and exposure to the mononuclear phagocytic system. Though unconfirmed, there is a potential for microclots to have formed in the blood during resuspension in sub-room temperature plasma, which placed a higher degree of shearing stress on the RBCs going through the filter, causing this effect. Early denaturation and oxidation of hemoglobin due to the mechanical stress induced by syringe pump and volumetric pump methods, leading to IgG binding to the red cell surface and removal from circulation, is another possible cause for early removal There were other limitations to this study such as the reduced half-life of transfused RBCs when compared to our current knowledge of dog erythrocyte lifespan (43 days in study vs 104-110d) attributed to the insult to RBCs during the biotinylation and processing. The use of biotin for RBC detection itself is not without worries of immunologic removal through anti-biotin antibody production, though previous studies have observed no development of such antibodies. Small sample sizes limiting the power of the results is a common limitation in the veterinary field, and this study is no exception. The results are most relevant to exact methods used in the study, and we can only make speculations on alternate setups to remove the use of microaggregate filters with the syringe pump (use of an in-line pediatric 170-260 µm filter or extraction of blood through a 170-260 µm filter administration set into a syringe, for example). The authors of the study recommended against using a syringe pump with 18 µm aggregate filters in the light of the results of their study, though considering the limitations, drastic changes to clinical protocols was not stated to be necessary. The current best practice considering this evidence would be to administer blood products via gravity flow for larger volume, higher flow rate transfusions as

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long as consistency in flow rate is monitored closely (as it can be influenced by catheter patency, positioning and motion by the patient, and amount of blood left in the bag). The syringe pump method is particularly useful when performing small volume transfusions such as in felines. A similar study performed with feline blood stated their observation of RBC survival time being unaffected by the syringe pump method.

PRBC has an expiration date of 42 days(?) Current practices in blood banking involve the usage of APS and additive nutrient solution which are labeled for 42 days of storage. More recent evidence gathered over the past decade indicates stored red blood cells to have impaired RBC survival, reduced efficacy as an oxygen carrier, and even incite adverse effects in the recipient causing mortality and morbidity. These changes are seen as early as 7 to 14 days into storage, and involve a collection of biochemical, biomechanical, and oxidative changes to the RBC and storage solution, all collectively referred to as “storage lesions”. Mature RBCs lack mitochondria and rely on glycolysis for ATP production, leading to a lowered pH. ATP production is reduced by the acidic environment, combined with depletion, leads to decreased RBC membrane integrity. Lowered pH also affects 2,3 diphosphoglycerate (2,3 DPG) level reducing hemoglobin’s effectiveness as oxygen carriers, though this effect is reversible and not significant in cats. Hemoglobin in longer stored RBC products contain free hemoglobin and microparticles that scavenge nitrous oxide (NO) upon transfusion and cause a vasoconstrictive effect impairing blood flow, stimulate coagulation, induce oxidative damage, and cause proinflammatory effects. Microparticles, which are vesicles that have budded off of cellular components, induce proinflammatory and procoagulant effects. Stored RBCs show morphologic changes to echinocytes and spheroechinocytes leading to a loss of deformability and impairment in normal flow through capillaries. Oxidative damage leads to increased hemolysis and methemoglobin formation decreasing viable RBC count and oxygen carrying capacity. There are many complicated mechanisms in play during RBC storage. To summarize the effects, storages lesions can lead to impaired RBC survival, reduce the efficacy of RBCs as oxygen carriers, and induce adverse effects such as arrhythmias, thrombosis, systemic inflammation, transfusion-related acute lung injury (TRALI), acute respiratory distress syndrome (ARDS), hypotension, and multiple organ dysfunctions. These changes occur as early as 7-14 days into storage, making supplying our patients with safe transfusion products a realistic challenge. Clinical impact of storage lesions is a topic of ongoing investigation while blood banks strive to balance provision of fresher products and minimizing wasting.

First transfusions are “free”? Compatibility testing for canine blood transfusions has traditionally been omitted in the interest of swift transfusions and financial considerations. This comes from the a widespread notion that the “first transfusions are free for dogs”, intended to state that canine RBC transfusions can be given without blood type matching (without typing the donor or recipient) or cross matching yet be performed without signs of immunologic complications, namely acute hemolytic transfusion reactions or anaphylaxis. This statement is made with the understanding that the most clinically significant dog erythrocyte antigen (DEA) is DEA 1, responsible for inciting acute hemolytic transfusion reactions when preexisting alloantibodies for the antigen is present. In 98% of the population, these antibodies are not present, so the first mismatched transfusion will only result in sensitization of the immune system to the antigen, leading to the development of antibodies over a course of approximately 4 days. This leads to a delayed hemolytic transfusion reaction, often asymptomatic as long as the patient has overcome the initial incident of anemia, or clinical symptoms of anemia as well as bilirubinemia and bilirubinuria may arise. Given the asymptomatic or mild nature of clinical signs, many have accepted this reason to forgo compatibility testing. However, the sensitization will lead to an acute hemolytic transfusion reaction in subsequent mismatched transfusions, resulting in hemolysis of transfused cells and likeliness of anaphylaxis. By omitting compatibility testing, we run the risk of priming a patient for such reaction in the next transfusion which may be handled similarly if the patient’s transfusion status is not noticed. A medical team may be placed in a situation where the transfusion status of the patient may be unknown (pet brought in by pet sitter who thinks there had been no transfusions, or adopted dogs who “probably” has not had a transfusion). In the case a patient presents with risk of imminent death from anemia, this practice may be justified with the knowledge of the risk. Blood typing of all blood donors and stocking of DEA 1 negative blood is highly recommended for use in these situations to avoid sensitization of the patient to DEA 1. If there is any uncertainty in the transfusion history of the patient, cross matching is appropriate as erythrocyte antigens aside from DEA 1 exist with limited knowledge on consequences from patients sensitized for these miscellaneous antigens (some reports of AHTR exist). Transfusions of canine RBCs without compatibility testing are not “free”, and certainly have the hidden costs of DHTR and sensitization. Cats possess alloantibodies for the RBC antigens foreign to them (aside from the very rare type AB cats), leading to hemolytic transfusion reaction even with first exposure.

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DEA 1 negative is the universal blood type? The concept of “universal” blood type indicates a blood type that can be given to any member of the same species without expectation of an immunologic reaction related to blood type mismatches. Because DEA 1 is the one antigen we know most about and leads to AHTR when mismatched for the second time, blood from DEA 1 negative dogs can be given without sensitization of DEA 1 negative and DEA 1 positive recipients, and often is considered as “universal”. There are, however, other RBC antigens such as DEA 3 through 8, dal, and other less known antigens confirmed to exist which can lead to sensitization when mismatched transfusions occur. Therefore, a donor should be tested negative for every RBC antigen we are capable of testing in order to truly considering it “universal”. This creates a challenge as 98% of the canine population is positive for DEA 4, and a donor negative in DEA 4 is virtually impossible to find. Fortunately this is not a clinical issue since the recipient is likely DEA 4 positive as well, allowing the blood types to match. Another challenge lies in our current inability to routinely test for DEA other than 1, 4, and 7 through a reference lab due to a lack of testing anti-sera (and anything aside from DEA 1 not available as in-house kits), preventing complete typing of our donors and timely testing of our recipients. Given our knowledge of additional RBC antigens, we should consider DEA 1 negative, 4 positive, 7 negative blood type as the “least antigenic”, and type our donors for all DEAs we are capable of, given finances permit it. DEA 1 negative can be considered safe blood to use from anecdotal evidence as reports of hemolytic transfusion reactions are rare, and cross matches should detect incompatibility issues arising from repeated exposure to the less known erythrocyte antigens. Cats have no universal donors, though type AB cats may receive transfusions from both type A and B donors.

Are blood transfusions between different species possible? Common knowledge dictates that blood product transfusions should be between members of the same species in order to prevent immunologic consequences. Despite this “common” fact, one may be surprised to hear an ongoing research to test interspecies transfusions, or xenotransfusions. Early experiments in blood transfusion in the 1600’s document a human patient receiving sheep blood, and showing no signs of reaction (at least on first exposure). Porcine red blood cells with modified antigens have been a topic of research in compatibility as human . In the veterinary field, feline blood is consistently in short supply, especially for patients with the rare blood type of B. Type B cats can only be transfused with type B blood as introduction of a small volume of type A blood will result in an acute hemolytic reaction and anaphylaxis. In addition, even for type A patients, blood supply may be short causing delays or inability to obtain blood products in a timely manner as the patient suffers life-threatening anemia. In these situations, veterinarians have attempted to use canine blood as a source of blood as it is more readily available, and can easily tolerate the small volume donations. There is limited amount of evidence available from a few studies conducted on canine to feline transfusions. The results of the studies concluded felines do not possess naturally occurring alloantibodies against canine erythrocytes. Compatibility testing methods such as slide-agglutination test and cross-matching only revealed agglutination on the minor-crossmatch. Of the total of 62 transfusions performed between the various studies, 5 cats showed signs of mild reactions, with tachypnea and pyrexia within 24 hours of the start of transfusion. Development of antibodies against canine RBCs were seen 4 to 7 days after the transfusion, indicating the transfusion led to sensitization of the immune system to the foreign antigens. Because of this, the life span of the transfused RBCs was approximately 4 days due to delayed hemolytic transfusion reactions while feline to feline transfusions allow RBCs to last 30 days. Subsequent transfusions resulted in anaphylaxis and were fatal in 66% of documented cases. While transfusion of dog blood to a feline patient is not the best solution to supplementing oxygen carrying capacity, it may be justifiable when faced with imminent death of the feline patient and without blood. A responsible medical team would discourage dog to cat transfusion and consider the method for situations where the patient 1) has no source of compatible cat blood (Type B cat with no stocked blood, donor, or nearby hospital with stock, for example) or hemoglobin based oxygen carrier solutions, 2) is imminently going to pass away without a transfusion or compatible blood will not be obtained soon enough (truly dying animal), 3) is expected to benefit from a short term oxygen carrying capacity gain, and 4) the owner understands risks and consequences. The method of xenotransfusion should not become a common practice and effort for practices to maintain a good source of cat blood should always be pursued without considering canine blood as “backup”.

Premedicating reduce chances of reactions? Premedication, or administration of antihistamines, glucocorticoids, or antipyretics in anticipation of immunologic complications to counter histamine and inflammatory mediators and suppress the effects, have been a traditional practice in transfusion medicine. While there is no veterinary evidence available addressing the efficacy of this practice, there are a number of human studies observing no difference in incidence of type I hypersensitivity reactions (allergic reaction) or febrile non-hemolytic transfusion reactions (FNHTR). Some clinicians reason that administration of premedication potentially masks early symptoms of immunologic complications delaying required interventions for treatment, advocating against it. Evaluation of the difference in severity between recipients with premedication or without premedication has not been performed, and remains a question whether this reasoning is valid. Human evidence is unfortunately not always directly translatable into veterinary practice, though expectations of similar

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physiological mechanisms exist. Studies evaluating effects of premedication and efficacy in prevention of hemolytic transfusion reactions are not apparently available, and the theoretical benefit is no justification for forgoing proper compatibility testing.

Is warming of blood products necessary? Warming of blood products in the interest of prevention hypothermia in the recipient is a consideration during blood product administration. Concerns for hemolysis of erythrocytes when warming during transfusion exist, and studies point towards little to no difference in markers for hemolysis in vitro when blood is warmed to typical body temperature. However, at non-emergent administration rates, blood reaching the patient through the line placed in a room temperature environment is easily at room temperature upon reaching the patient, and will not contribute to a significant decrease in body temperature. In the case of rapid transfusions of large volumes into small patients, warming of the blood may be indicated with care taken to be evenly warmed to 35- 37°C and not exceed 42°C close to the patient to minimize loss of heat. Hypothermia is also a documented complications related to massive transfusions. Aside from these situations, in many cases warming effort directed at the patient is most effective in treating hypothermia without causing risk of damage to the RBCs.

Is plasma indicated for use in hypoproteinemia? Parvoviral enteritis? Plasma contains many proteins of interest, namely hemostatic proteins, albumin, and immunoglobulins. Hypoproteinemia, specifically hypoalbuminemia, occurs in many critically ill patients with protein-losing disorders including protein-losing enteropathies, protein- losing nephropathies, liver failure, trauma, burn wounds, etc. This leads to a loss of intravascular colloid osmotic pressure (COP), and subsequent consequences. Administration of plasma products (, frozen plasma, or ) have been used as a method in supplementing albumin for COP. However, the amount of plasma required to raise the patient’s albumin level by 1g/dL is approximately 40-50mL/kg. This is equivalent to 1.1L of plasma (9.5 units) for a 50# patient. The amount of plasma required to make a significant difference in the measurable level of albumin is both cost prohibitive and pose a large immunologic risk to the patient. Whether increasing the albumin level to a normal value (>2g/dL) will lead to increased chances of a positive outcome is still unclear, and difficult to advocate. Similar concepts can be applied to the usage of plasma products derived from survivors of parvovirus infection. Clinicians have theorized that transfusion of plasma containing antibodies against canine parvovirus (CPV) will aid in recovery from CPV infections. A study evaluating use of a single dose of plasma containing CPV antibodies in its efficacy versus saline placebo saw no significant difference in reducing clinical signs, viremia, or speeding recovery. The volume used in this study (12mL) may be a limitation to the efficacy of the compared treatment, though the amount of plasma required for an adequate dosage of antibodies is unknown, and is likely to be at similar or higher levels of dosage for albumin supplementation. Thus, same concerns prevent use of plasma in this manner.

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Shock has Two Faces: The Keys to Perfusion Kenichiro Yagi, BS, RVT, VTS (ECC, SAIM) Adobe Animal Hospital Los Altos, CA

Shock has two faces. Shock is defined as an inadequate production of cellular energy, very commonly brought on through forms of circulatory failure. Hypovolemic (inadequate circulating blood volume), cardiogenic (inability for heart to create forward flow), distributive (loss of systemic vascular resistance), and obstructive (obstruction of large vessels, sometimes not considered its own category) shock describe one aspect of inadequate delivery of oxygen (DO2) leading to inadequate production of cellular energy. Shock despite proper circulatory function arises from metabolic dysfunction due to inadequate substrate supply or dysfunctional metabolic mechanisms. Oxygen is a very important component in carrying out aerobic metabolism, a vastly more efficient and sustainable method of energy production than anaerobic metabolism which takes place with the absence of oxygen. Lack of oxygen being delivered to tissues from inadequate oxygen content in arterial blood lead to what is known as hypoxemic shock, and may occur from varying reasons.

Oxygen in energy production The importance of maintaining adequate DO2 lies in the difference of the amount of adenosine triphosphate (ATP) produced in the presence and absence of oxygen. ATP is considered the “currency of cellular energy”, providing energy for cellular processes required to maintain life as phosphate groups are cleaved off resulting energy release and formation of adenosine diphosphate (ADP) or adenosine monophosphate (AMP). ATP is involved in cellular signaling, DNA and RNA synthesis, muscle contraction, cytoskeletal maintenance, active transporting, and many other cellular functions. There is a finite amount of ATP available within a body, and a constant recycling of ADP and AMP into ATP is required to keep up with energy demands. In the presence of oxygen, 38 ATP molecules are generated from metabolism of a single glucose molecule undergoing oxidative phosphorylation occurring in the mitochondria. In contrast, a single glucose molecule yields two ATP molecules through anaerobic metabolism. The presence of oxygen is imperative in efficient energy generation. Provided there is adequate functional hemoglobin levels and normal respiratory function, DO2 is dependent on the ability to circulate the oxygen containing blood to tissues requiring oxygen, called perfusion. The mathematical expression of DO2 is: DO2 = CaO2 x CO. Oxygen contained within blood exists in two forms; dissolved in the plasma and bound to hemoglobin. The amount of oxygen dissolved in plasma depends on the partial pressure of oxygen (PaO2), with 1 mmHg creating enough tension to result in 0.0031mL of dissolved O2 per dL of plasma. Each gram of hemoglobin is able to theoretically carry 1.39mL of O2 when fully bound with oxygen, making up a significant portion of oxygen content of blood. In reality, there are portions of dysfunctional hemoglobin lowering this to approximately 1.34mL. In addition not every hemoglobin molecule will be fully bound to oxygen in every situation (SaO2, or arterial oxyhemoglobin saturation) adding some variability. With all of these considerations in mind, the resultant formula to quantify DO2 is the following, expressing the impact lowered hemoglobin concentration and saturation of the hemoglobin will have on overall delivery of oxygen: DO2 = [(1.34 x Hgb x SaO2) + (0.0031 x PaO2)] x CO. In animals without disease, DO2 is significantly above oxygen consumption (VO2), supplying a very comfortable buffer of available oxygen for energy production. This buffer allows for sudden changes in oxygen demand through changes in cellular metabolic rate or reduction in CaO2. When DO2 is significantly compromised (termed critical oxygen delivery), tissue hypoxia results and increased lactate levels and lowered pH are seen. The oxygen extraction ratio can also be used to express the level of oxygen consumed in relation to DO2 (O2ER = VO2/DO2). Higher oxygen consumption or lower DO2 leads to a higher ratio. The normal O2ER value is approximately 0.2, though different organ systems have varying O2ER (normal O2ER of the heart is 0.6, making it more 2 2 sensitive to hypoxemia). A normal DO2, VO2, and O2ER in dogs were observed to be 790ml/min/m , 164ml/min/m , and 0.205, respectively in one study. Another couple of studies cite a normal DO2 of 20-25ml/kg/min and observed critical oxygen delivery levels of 8-11ml/kg/min regardless of the cause (anemia, hypoxemia, and cardiac tamponade). A patient is said to be in hypoxemic shock when Hgb, SaO2, or PaO2 levels are low enough for DO2 to reach this critical oxygen delivery level. In clinical settings, measurement of specific values such as CO and VO2 (though can be estimated) are rather difficult, and we utilize this concept in determining when a patient is suspected to be in hypoxemic shock rather than making direct comparisons.

Tissue perfusion The maintenance of normal blood pressure and tissue perfusion depends on adequate CO, and systemic vascular resistance (SVR). The most common form of reduced DO2 and shock occurs secondary to reduction in CO or SVR. CO is can be reduced through a loss of intravascular volume, leading to hypovolemic shock. Hypovolemic shock can be caused by many situations leading to hypovolemia, such as internal or external hemorrhaging, fluid loss through vomiting, diarrhea, polyuria, exposed subcutaneous surfaces (burns, bit wounds) and/or reduced water intake. A loss in circulating blood volume leads to a diminished venous return and preload to the heart, 970

reducing the stroke volume (SV). A significant degree of reduced CO due to decreased SV is compensated for through an increase in heart rate (CO = SV x HR). SV itself is improved through increased contractility, or a more forceful contraction of the heart to eject a larger volume of blood. Reduced blood flow to the kidneys stimulates the renin-angiotensin-aldosterone system, increasing production of aldosterone leading to sodium retention, increasing plasma osmolarity and encouraging shifting of fluid to the intravascular compartment. Increased antidiuretic hormone (vasopressin) also promotes water retention, reducing urinary fluid loss. While vasoconstriction does not directly add to intravascular volume, its occurrence increases systemic vascular resistance, improving blood pressure and circulation of the reduce blood volume. Patients faced with hypovolemia initially show signs of compensatory shock, involving tachycardia, normal prolonged capillary refill time (CRT), normal to pale mucous membranes, tachypnea, and cool extremities. Pulse quality and blood pressure may be mostly normal, and subtle depression in mentation may be seen. As intravascular volume continues to be lost, compensatory mechanisms will be unable to adequately maintain proper perfusion, and later signs of shock such as pale mucous membrane, prolonged CRT, poor pulse quality, depressed mentation, and hypotension will be seen. Uncorrected poor perfusion will lead to organ ischemia, leading to organ failure and death. CO can be significantly affected by cardiac dysfunction as well. Congestive heart failure from cardiomyopathy can reduce contractility of the heart or reduce end-diastolic volume, decreasing SV and subsequently, CO. Cardiac arrhythmias may lead to improper filling, ejection, and effectiveness of the heart to create CO. Cardiac tamponade, occurring when effusion fills the pericardial space creating external pressure on the myocardium significant SV. Certain drugs may have cardiovascular depressant effects or cause myocardial conduction defects, leading to reduced CO. Any cardiogenic cause leading to reduced CO and resultant shock is called cardiogenic shock. is another form of shock characterized by an inappropriate distribution of blood flow and volume. One example can be considered , resulting in profound vasodilation causing “relative hypovolemia” and a reduction in SVR, leading to reduced BP and poor perfusion. Systemic inflammatory response syndrome (SIRS) and septic shock (SIRS due to an infectious cause) involves vasodilation caused by cytokine and other inflammatory mediator secretion leading to a hyperdynamic phase involving hyperemic mucous membranes, bounding pulses, fever, and tachycardia. As the hypoperfused state is allowed to persist, myocardial damage leads to reduced cardiac output, and clinical changes to the patient to more classic signs of shock. Tachycardia, pale mucous membranes, prolonged CRT, cold extremities, poor pulse quality, and depressed mentation will be signs of significantly impaired perfusion. Patients suffering from gastric dilatation-volvulus (GDV) will have a distended stomach compressing the intra-abdominal vessels (caudal vena cava, portal veins, and splanchnic vessels), impeding venous return to the heart leading to a reduced CO. This is considered obstructive shock by many (while many others consider it a form of distributive shock), where major blood vessels are occluded or carry reduced blood flow contributing to poor CO. The cause of shock in GDV is actually muti-faceted, since the occlusion of major vessels leads to portal hypertension and splanchnic pooling, leading to effusion of intravascular fluid into the abdominal cavity and interstitium, contributing to hypovolemia. Additional fluid loss may also occur due to vascular injury to gastric vessels as it is stretched, and repeated vomiting. Many disease processes involve different causes of shock occurring in varying in degrees, leading to the cumulative effect of reduced CO and DO2.

Monitoring The effectiveness of therapy can be determined through physical parameters as well as laboratory values. Physical perfusion parameters consist of mentation, heart rate, pulse quality, mucous membrane color, CRT, core to extremity temperature gradient. A patient in shock will have dulled mentation, increased heart rate (bradycardic in decompensated shock), poor pulse quality, pale mucous membrane (hyperemic if early vasodilatory shock), prolonged CRT, and a significant difference in core vs extremity temperature. These physical parameters should be monitored as shock is treated to ensure signs of poor perfusion are alleviated as therapy is continued. Except during compensatory shock, hypotension would be present and thus blood pressure should be monitored for changes. If hypotensive, initiation of therapy should be aimed to increase to a normal ranges (MAP 70-120mmHg). Blood pressure may be measured indirectly via Doppler, oscillometric monitors, or directly through an arterial catheter and pressure transducer setup. Hypoperfusion of tissues and inadequate oxygen delivery results in anaerobic respiration. Anaerobic respiration is performed in hypoxic situations, leading to hyperlactatemia, and resultant metabolic acidosis. Normal lactate level dogs and cats is 0.5-2.0 mmol/L. Elevated lactate measurement indicates significant lactate production overwhelming the liver’s metabolic clearance rate. Serial lactate measurements as fluid resuscitation is performed will allow monitoring of changes in the lactate level. A swift decrease in lactate level during fluid resuscitation serves as a positive prognostic indicator in patients with shock. Other assessment tools such as central venous pressure may help guide fluid therapy and monitor fluid balance in a patient as fluid therapy is continued. Mixed venous oxygen saturation (SvO2), or oxygen saturation of hemoglobin at the pulmonary artery (after maximal oxygen extraction), will be decreased when DO2 is decreased. Since pulmonary arterial catheters are not commonly placed in veterinary medicine, central venous oxygen saturation (ScvO2) can be used as an indicator for SvO2, as the values parallel each other

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closely, and a reduced ScvO2 typically correlates to a reduced SvO2. Urine output serves as an indicator for adequate renal perfusion, and will be greater than 1ml/kg/hr when blood flow is adequate. Urinary catheters are placed in critical care patients for the purpose of urine output monitoring. In the absence of renal disease, urine specific gravity may give clues as to adequate fluid infusion rate as well. Cardiac output itself can be monitored through advanced modalities such as thermodilution or lithium measurement, though not readily available in veterinary medicine.

Therapy Treatment for shock will vary depending on the underlying cause. Hemorrhaging may require surgical intervention, or treatment of coagulopathies. Treatment of sepsis is a very intensive process including early antimicrobial administration. Cardiomyopathies may require various anti-arrhythmics, anti-hypertensives, or inotropics. These are only a few examples. Regardless of the underlying cause, there is a general strategy that can be applied to treating patients in shock which is aimed at reversing the restoration of tissue perfusion and preventing progression of shock while the underlying causes are treated. Obtaining vascular access is one of the first steps in restoring cardiovascular stability in states of shock. A larger diameter, shorter catheter will cause the least amount of resistance for fluid boluses to be administered and recommended. Many of these patients, however, will have a compromised cardiovascular system often making placement of intravenous catheters difficult. Placement of a jugular venous catheter or intraosseous catheters may be more readily possible compared to placement of peripheral venous catheters and should be considered very early in attempting vascular access. The first line of therapy is isotonic crystalloid therapy in all forms of shock aside from shock arising from cardiomyopathies (adding intravascular volume in congestive heart failure will exacerbate the congestion). A IV crystalloid bolus dose of 20ml/kg may be given, and the patient re-evaluated for further need. Crystalloids are thought to remain in the intravascular space only for a short amount of time (25% remaining approximately 30 minutes after infusion), and may require re-dosing at this point. In the case of hemorrhaging, hypotensive resuscitation, keeping the MAP approximately 60mmHg, may be beneficial in preventing exacerbation of bleeding. Infusion of crystalloids is aimed at replacing lost intravascular volume, or adding intravascular volume to combat relative hypovolemia caused by vasodilation. Synthetic colloids such as hetastarch and tetrastarch provide higher osmolarity than crystalloids, allowing better retention and even causing shifting of fluid into the intravascular space, increasing intravascular volume and better tissue perfusion. In human medicine, there was recently a warning issued regarding the use of hetastarch and it being linked to renal injury. While human kidneys and canine/feline kidneys seem different in terms of sensitivity to insult, hetastarch is now recommended to be used with caution. Natural colloids are available in the form of albumin contained in plasma or albumin concentrate. Plasma may be used to supplement albumin levels in hypoalbuminemia. Hypoalbuminemia may result due to protein losing enteropathy or nephropathy, septic peritonitis, trauma, burns, and any other pathologies causing protein loss. However, the dose required for this particular use is 20-25mL/kg to achieve an increase of 0.5g/dL in plasma albumin. For example, a 25kg patient with an albumin level of 1.0g/dL will require 1000-1250mL of plasma to regain a low normal plasma albumin level of 2.0g/dL. In addition, this is not taking into account ongoing loss from the patient’s pathology. Use of plasma in this manner will pose a higher transfusion related complication risk, be an inefficient use of plasma, and will be at a significant cost to the owners. Serum albumin concentrate is a better source of albumin. Human serum albumin (HSA) has been used in canine patients with hypoalbuminemia. However, these infusions have a significant chance of an immunologic reaction as human albumin differs from canine albumin by 20% of its amino acid sequence. Previous sensitization to human albumin and subsequent acute hypersensitivity reactions are especially a concern when repeat doses are necessary. A study found presence of anti-albumin antibodies in dogs without prior exposure to human serum albumin, which was hypothesized to be from prior vaccinations involving production in bovine albumin cultures. Canine specific albumin has recently been produced as a commercial product, observed to increase serum albumin levels in the recipients with a low chance of immunologic complications. The most recent published study indicated albumin administration in dogs with septic peritonitis to have improved albumin level, Doppler blood pressure values, and colloid osmotic pressure measurements, as well as a comment on the association between albumin transfusion and survival. A connection between an improvement in serum albumin level and ultimate survival continues to be a topic under investigation, Hypertonic saline (7% compared to 0.9% in normal saline) possesses higher osmolarity than crystalloids, which provides a hyperosmolar shifting of fluids into the intravascular space upon injection. The effect of hypertonic saline has a fast onset though the effect is also short lived. There may be additional beneficial effects such as reduced endothelial swelling, modulation of inflammation, and increased cardiac contractility. A mixture of hypertonic saline and synthetic colloids given simultaneously has been seen to improve hemodynamic status better than each given individually. Blood products such as pRBC and plasma may need to be administered in cases of severe hemorrhaging or coagulopathy. Blood products are not recommended to be used solely as volume replacement due to potential immunologic and non-immunologic complications. RBCs are warranted for existing or anticipation of clinically significant anemia due to the rate of hemorrhaging seen. Plasma is useful in replacing coagulation factors. Hemoglobin

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based oxygen carrying solutions such as Oxyglobin, if available, will allow replacement of oxygen carrying capacity as well as providing colloidal effects without risk of immunologic complications. When efforts in providing better intravascular volume are not sufficient in restoring adequate perfusion, vasopressor and inotropic therapy is required. Vasopressors function to provide vasoconstriction improving perfusion by increasing SVR. Vasopressors such as dopamine, norepinephrine, phenylephrine, epinephrine, and vasopressin may commonly be used. Inotropes such as dobutamine improve cardiac output through increasing myocardial contractility. As with many conditions, successful treatment of shock depends on early recognition, assessment, and swift response and treatment of shock. Quick determination of the cause of impaired perfusion will allow for the appropriate fluid resuscitation strategy and medical management. Technicians play a large role in providing the monitoring of the patient as therapy is performed, through frequent monitoring of physical perfusion parameters and working in conjunction with the veterinarian to provide additional measures.

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