Approaches to Wound Closure in Challenging Circumstances

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Vet Times The website for the veterinary profession https://www.vettimes.co.uk APPROACHES TO WOUND CLOSURE IN CHALLENGING CIRCUMSTANCES Author : Ivan Rakic Categories : Vets Date : February 7, 2011 Ivan Rakic illustrates the practical uses of reconstructive procedures in the treatment of injuries to dogs, despite limited choice of drugs and equipment GAINING experience in three European countries – the UK, Iceland and Serbia – that differ so much in culture, tradition, economy and even climate has given me a broad outlook. The veterinary work can be quite changeable, but the aim is always the same – to help promote animal health and wellbeing. Trying to establish a small veterinary practice in Serbia is not easy, and the country is still recovering from the war and difficult times. Small animal veterinary practice in Serbia has, however, dramatically improved in the past decade with the support of the Federation of European Companion Animal Veterinary Associations (FECAVA), and Belgrade has hosted many experts and lecturers in the veterinary field. Most of the small animal vets in Serbia are now trying to work to the standards set by western Europe, but, unfortunately, changes in veterinary policy, regulations and the import and registration of drugs are very slow, which often impairs the development and quality of veterinary practice in the country. I live in the village of Jabucje, which is 50 miles from the capital Belgrade, in what is considered to be a rural area. Besides companion animals, I also treat wildlife. Almost 15 per cent of my patients are wild animals and include birds, badgers, foxes, jackals, pine martens and even bears. Most of 1 / 5 them are injured, and some have been rescued following illegal hunting. I am also involved in a project to establish a wildlife rescue centre. I would like to introduce several cases from my own practice that demonstrate how reconstructive surgical procedures can still be performed, despite the limited choice of drugs and lack of sophisticated gadgets. From the point of animal welfare, some of these cases show that the animals were neglected by the owners or abused in illegal badger fighting. All these cases have in common large skin defects, heavily contaminated with soil and hair, and the presence of a large amount of devitalised tissue. Rescue dogs, particularly those brought to surgery after badger fighting, usually suffer from wounds that are more than three days old. In these cases I had to apply very aggressive antimicrobial treatment and lavage with solutions that would help eliminate the necrotic tissue and stimulate growth of granulation tissue. Case one • Rescued terrier • Age unknown • Injured in badger fighting (illegal in Serbia). This terrier was rescued following a fight with a badger. Skin from the lower jaw had necrotised together with the underlying soft tissue, which sloughed, leaving the mandibular bone uncovered. The dog initially received fluid therapy, NSAID and antibiotics. The wound was heavily contaminated with sand and hair, and much devitalised tissue was exposed. Copious lavage with saline solution was used to clean the wound and remove the contamination as far as possible. Lotagen in a three per cent to four per cent solution was used for lavage of the wound, as an antiseptic and also to encourage separation of the necrotising tissue from the vital tissue. Some may find this drug strange and out of fashion, but on this occasion it was the drug of choice. Lotagen can distinguish pathologically altered from healthy tissue. Functionally damaged cells are coagulated and shed. Intact cells are stimulated to construct a new mucous membrane or skin layers. Lotagen triggers constriction of smooth muscle fibres. In the walls of minor arteries it results 2 / 5 in vasoconstriction. After a few days of treatment the wound was clear of debris and dead tissue. (Figure 1a) and appositional sutures were placed. Another drug that is not often used is a solution of iodoform in diethyl ether. This is a strong antiseptic and also stimulates growth of the granulating tissue. Figures 1b and 1c show the wound during treatment with iodoform. Figures 1d and 1e demonstrate progress a few weeks later, and the end of treatment is shown in Figure 1f. Badger fights I occasionally see terriers after they have been involved in fights with badgers and in most of the cases the wounds look like the one described in case one. During the fight, the badger bites the dog’s lower jaw and ventral neck. The badger has rather blunt teeth and stronger jaws than canines. This is responsible for causing the terrible damage to the soft tissue; although the skin, due to its elasticity, doesn’t show much damage on the first day. One can notice large swellings around the lower jaw and ventral neck, with small holes or scratches on the skin, while the subcutaneous tissue is completely destroyed and devitalised. During the next few days, the skin also necrotises, sloughing and revealing an open wound. I understand that some colleagues may disagree about using iodoform and lotagen solution for wound treatment. However, in my situation I didn’t have a better option and, in my experience, these drugs did the job quite well. There is a saying in Serbia: “The wound on the dog will heal on the dog.” This explains the dog’s ability to recover well from any wound. I would be more satisfied if we could find a “medicine” that would prevent the cruelty that causes such injures in animals rather than searching for a miracle that would treat any wound. Case two • Terrier • Male, 10 years old 3 / 5 • Injured in a fight with another dog This working terrier was found suffering from severe dehydration after he went missing from home for five days. A large haematoma was evident on the ventral neck. Several days later, the skin necrotised and sloughed, revealing an open wound beneath. (Figure 2a). On the first day the dog received fluid therapy and antibiotics – metronidazole and amoxycillin with clavulanic acid and NSAIDs. The wound was treated with a lavage of saline solution and povidone iodine solution. A solution of iodoform in diethyl ether was also used. Figure 2b shows the animal 10 days later and just before surgery. From my experience, solution of iodoform in diethyl ether is a very potent antiseptic and stimulator of granulation tissue growth. As an old-fashioned antiseptic, it is not widely accepted; even in Serbia. Iodoform is a powder that dissolves easily in diethyl ether. Ether is used as a carrier because it evaporates quickly, leaving the iodoform equally spread over the surface of the wound. In the 1930s, iodoform was commonly used in wound treatment. James Herriot had used it a lot. Nowadays, it is still used in human medicine as an iodoform gauze for wound dressing and in dentistry as well. The skin defect was covered by creating a flap using skin from the surrounding region. (Figure 2c). The healing is shown in Figure 2d. Case three • Golden retriever • Male, eight months old • Road traffic accident The dog had a degloving injury to the flank and the proximal part of the left hindleg, with extensive haematomas and contusion present over the lumbosacral region. The wound was heavily contaminated. The dog initially received fluid therapy, NSAIDs and antibiotics. The wound was closed after removal of the debris and contamination although the prognosis for the survival of the skin was poor due to the damage and devitalisation. A large amount of the skin necrotised and sloughed in the first 10 days. (Figure 3a). 4 / 5 Besides saline solution for the wound lavage, povidone iodine solution and a solution of iodoform in diethyl ether was also used as an antiseptic and to stimulate granulation of the tissue. (Figure 3b). Skin from the dorsal region was used to create the flap. Simple interrupted sutures were used, together with horizontal mattress sutures to provide a better closure and prevent tension of the flap. The horizontal mattress sutures were removed after four days. About 20 interrupted sutures were placed through the skin of the flap into the granulation tissue underneath to immobilise the flap. The distance between these sutures was two to three centimetres. The drain was placed on the most distal part of the wound and was removed after four days. (Figure 3c). Complications arose after several days when the distal part of the flap close to the drain necrotised (Figures 3d and 3e). Impaired circulation, tension and loose contact between the flap and the granulation tissue underneath caused the failure of that part of the flap. The necrotic part of the flap was removed and a small flap was created a week later. (Figure 3f). Figure 3g shows the wound healing nicely, and Figure 3h illustrates the hair regrowth. References Welch Fossum T (2006). Small Animal Surgery (3rd edn), Mosby. Tintinalli J E, Kelen G D and Stapczynski J S (1999). Emergency Medicine: A Comprehensive Study Guide (5th edn), McGraw-Hill Inc, US. 5 / 5 Powered by TCPDF (www.tcpdf.org).
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