Andrew Smith, DVM New England Equine Practice Intern Overview Anatomy review Colic On the farm Decision to refer Referral hospital Decision for surgery Post-operative considerations
Esophagus 4-6ft 2/3 striated muscle 1/3 smooth muscle Transport Stomach Capacity ~ 5-15 L 3 regions 2 different mucosal linings Start of digestion
Small Intestines Varies in length 50-80ft Duodenum ~ 3-4 ft Jejunum ~ 50-60 ft Ileum ~ 3 ft Carbohydrate, fat, protein digestion
Small Intestines Varies in length 50-80ft Duodenum ~ 3-4 ft Jejunum ~ 50-60 ft Ileum ~ 3 ft Carbohydrate, fat, protein digestion
Small Intestines Varies in length 50-80ft Duodenum ~ 3-4 ft Jejunum ~ 50-60 ft Ileum ~ 3 ft Carbohydrate, fat, protein digestion
Cecum Length ~ 3-4 ft Capicity ~ 30 L Electrolyte and water absorption Microbial digestion Large Colon Length: 10-12 ft Capacity: 50-60 L Four segments 3 flexures 2 areas of narrowing Microbial digestion Fluid Absorption
Large Colon Length: 10-12 ft Capacity: 50-60 L Four segments 3 flexures 2 areas of narrowing Microbial digestion Fluid Absorption Small Colon Length: 10-12 ft Transverse Descending Absorption of water Form fecal balls
Leading cause of death in horses behind old age 10 % of horses develop colic annually 10% of horses with colic require surgery Monetary losses of ~250 million/year
What to do? Take Away Feed Call your veterinarian Visual examination Signalment and history Walking? Recent changes? Housing/environment Sedation? Activity level Banamine? Parasite Control Diet Oral or IV only Medical history Prior colic/colic surgery Habits/Vices
Colic Exam TPR Abdominal contour Pulse quality, gum color, CRT Skin tent Auscultate chest and abdomen Approximate Skin Tent Degree of Dehydration (seconds) enophthalmia % Normal 2-3 None 6 4-6 None 8 6-8 Mild 10 >8 Obvious Rectal Palpation Urogenital tract Ventral band of cecum Aorta Left kidney N-S ligament Spleen Pelvic flexure Small colon
Rectal Palpation Urogenital tract Ventral band of cecum Aorta Left kidney N-S ligament Spleen Pelvic flexure Small colon
Rectal Palpation Urogenital tract Ventral band of cecum Aorta Left kidney N-S ligament Spleen Pelvic flexure Small colon
Rectal Palpation Urogenital tract Ventral band of cecum Aorta Left kidney N-S ligament Spleen Pelvic flexure Small colon
Nasogastric Intubation Quantity important > 2L abnormal Gas, color, pH lesser significance Nose bleed
Treatment options Decision to refer Examination Normal Refer Parameters Colic Resolving Recurrent, unresponsive Pulse <48bpm 60-80bpm
Membrane Color Pink Congested
CRT <2s 3s
Gut Sounds Present Absent
Rectal Normal Distended intestines, small intestines Nasogastric Reflux <2L >2L Clinical picture
Ancillary Diagnostics Abdominocentesis Fecal sand Ultrasound N-S entrapment Motility Size and thickness Blood Work Systemic exam Endoscopy Gastric ulcers Esophageal obstructions Laparoscopy Radiography Foals Enteroliths Sand Diaphragmatic hernias Ancillary Diagnostics Abdominocentesis Fecal sand Ultrasound N-S entrapment Motility Size and thickness Blood Work Systemic exam Endoscopy Gastric ulcers Esophageal obstructions Radiography Foals Enteroliths Sand Diaphragmatic hernias Ancillary Diagnostics Abdominocentesis Fecal sand Ultrasound N-S entrapment Motility Size and thickness Blood Work Systemic exam Laparoscopy Endoscopy Gastric ulcers Esophageal obstructions Radiography Foals Enteroliths Sand Diaphragmatic hernias
Ancillary Diagnostics Abdominocentesis Fecal sand Ultrasound N-S entrapment Motility Size and thickness Blood Work Systemic exam Laparoscopy Endoscopy Gastric ulcers Esophageal obstructions Radiography Foals Enteroliths Sand Diaphragmatic hernias
Ancillary Diagnostics Abdominocentesis Fecal sand Ultrasound N-S entrapment Motility Size and thickness Blood Work Systemic exam Laparoscopy Endoscopy Gastric ulcers Esophageal obstructions Radiography Foals Enteroliths Sand Diaphragmatic hernias
Treatment options Surgery ? Persistent or recurrent pain despite adequate analgesia Presence of enterolith Distended edematous small intestines without motility Physiological deterioration despite stabilization Progressive abdominal distension Abdominal palpation findings of small intestinal distension, colonic displacement, very firm intra-luminal mass Serosanguineous abdominal fluid with elevated protein Prognosis
Short term Long term Small intestine: 85% 75% simple obstruction Small intestine: 75% 50% strangulating obstruction Large intestine: 90% 85% simple obstruction Large intestine: 50% 35% Strangulating obstruction Post-operative considerations At the hospital At home Remove sutures 12-14 days Anti-inflammatories Gradual return to normal IV Antibiotics: 1-5 d diet 1m stall rest, 1 m small IV fluids paddock, 1 m slow return Gradual return to feed to exercise Check temperature, Hand-walking manure production, water consumption Watch for incisional Goal: infections What goes in, must Abnormal behavior come out! Post-operative considerations Recovery stall complications Endotoxemia Postoperative ileus Incisional infection Adhesions Peritonitis Laminitis What you can do Prevention is key Quality feed, hay, water. Sand management. Routine dentistry Regular, effective de-worming Adequate turn-out If your horse is colicky Don’t panic! Call your veterinarian Withhold food and hay Take them for a walk if not severely painful Monitor Signs of pain, heart rate, respiration, and temperature Allowing your horse to lay down is fine but rolling is not.
Diseases of the stomach Gastric ulcers Neonates, weanlings Intensive training Periods of starvation
Gastric impactions Feeds Wheat, barley, beet pulp Dental disease Simple obstructions of the small intestines Proximal enteritis Etiology unknown C. perfingens Fever, depression Large amount of reflux Improve after gastric decompression Ileal impaction Poor quality hay Tapeworm infestation Muscular hypertrophy of ileum Simple obstructions of the small intestines Proximal enteritis Etiology unknown C. perfingens Fever, depression Large amount of reflux Improve after gastric decompression Ileal impaction Poor quality hay Tapeworm infestation Muscular hypertrophy of ileum Strangulating lesions of small intestines Volvulus Rotation of >180 about the mesentery Primary displacement 2nd to other lesions
Foals: 2-4 m Epiploic Entrapment Cribbing Usually left-to-right Strangulating lesions of small intestines Volvulus Rotation of >180 about the mesentery Primary displacement 2nd to other lesions Foals: 2-4 m Epiploic Entrapment Cribbing Usually left-to-right
Strangulating lesions of small intestines Pedunculated lipomas Benign fatty tumour suspended by mesentery Size of stalk more important Older geldings Intussusception Jejunum, ileum, cecum Enteritis, ascarids, tapeworms, dietary changes, anastomosis, masses Foals > aged Strangulating lesions of small intestines Pedunculated lipomas Benign fatty tumour suspended by mesentery Size of stalk more important Older geldings Intussusception Jejunum, ileum, cecum Enteritis, ascarids, tapeworms, dietary changes, anastomosis, masses Foals > aged
Strangulation lesions of small intestines Mesenteric rents Congenital Trauma or mesenteric stretching Mares in foal Inguinal hernias Indirect vs direct Congenital vs acquired Standardbreds, tennessee walkers, saddlebreds Strangulating lesions of small intestines Mesenteric rents Congenital Trauma or mesenteric stretching Mares in foal Inguinal hernias Indirect vs direct Congenital vs acquired Standardbreds, tennessee walkers, saddlebreds
Diseases of the cecum Cecal impactions Dental disease Poor quality hay Decrease water intake Tapeworms Hospitalization Prior surgery/ anesthesia Lack of exercise Disruption of cecal pacemaker
Simple obstructions of the large colon Gas distension/impaction Stall rest/change in exercise Water intake Parasites Travel Dental disease Previous colic Lameness/pain High concentrate diets Poor quality roughage Sand Hospital stay/anesthesia DDX: Impaction, displacement, torsion, ileus (colitis)
Displacements Left dorsal displacement Nephrosplenic entrapment Excessive gas formation Abnormal motility 2nd impaction
Right dorsal displacement Varying presentations
Displacements Left dorsal displacement Nephrosplenic entrapment Excessive gas formation Abnormal motility 2nd impaction
Right dorsal displacement Varying presentations
Large colon volvulus EMERGENCY!!!!!!!!!!!!!!! Acute vs chronic Risk factors Recent parturition Recent dietary changes Recent access to lush pasture Really a torsion >180 = strangulating lesion
Diseases of the small colon Impactions Predispositions similar to large colon impactions Miniature horses, ponies, older horses Lipomas Volvulus, Herniation, Intusseption rare Enterolithiasis
Magnesium ammonium phosphate Need a nidus Right dorsal colon, small colon California, Florida Arabians, Morgans, Saddlebreds, donkeys, Miniature horses Alfalfa <50% of time spent outdoors