Maggot debridement therapy for serious horse wounds - a survey of practitioners

Hoof disease and injuries are common and serious problems for equines. Maggot debridement therapy (MDT) has been used to treat problematic wounds in humans, but has been used only rarely in other animals. US veterinarians who had employed MDT were surveyed to investigate their reasons for the choice of this treatment and their clinical experiences with it. Between 1997 and 2003, 13 horses were treated by eight veterinarians who used MDT to control infection or debride wounds, which could not easily be reached surgically or were not responding to conventional therapy. Seven animals were lame, and six were expected to require euthanasia. Following maggot therapy, all infections were eradicated or controlled, and only one horse had to be euthanased. No adverse events were attributed to maggot therapy for any of these cases, other than presumed discomfort during therapy. The data collected suggest that maggot therapy could be useful for treating some serious equine hoof and leg wounds.     

The Association of Propofol Usage With Postoperative Wound Infection Rate in Clean Wounds: A Retrospective Study

OBJECTIVE: To determine if the use of propofol influences the postoperative infection rate of clean surgical wounds in dogs and cats. STUDY DESIGN: Retrospective study. SAMPLE POPULATION: 863 dogs and cats undergoing clean surgical procedures. METHODS: Medical and anesthetic records of surgical cases used as part of a previously described epidemiologic study on postoperative wound infection rates were reviewed. The records of all animals with clean surgical wounds were reviewed to determine if propofol had been used for anesthetic induction or maintenance during the procedure. To determine the effect of propofol use on wound infection rate, data were analyzed using Fisher's exact test, followed by multiple logistic regression to adjust for various factors, including surgery time, time from clipping to surgery, antibiotic usage, coexisting distant infection, endocrine disease, and the use of immunosuppressive drugs in the perioperative period. RESULTS AND CONCLUSIONS: Of 863 dogs and cats with clean surgical wounds, 46 received propofol as part of the anesthetic protocol. A total of 6 of 46 animals (13%) receiving propofol developed postoperative wound infections, compared with 33 of 817 animals (4%) not receiving propofol (P = .014; % difference = 9%; 95% CI = 0.5% to 24%). Adjusting for all other factors evaluated, animals receiving propofol were 3.8 times more likely to develop postoperative wound infections compared to animals not given propofol (95% CI = 1.5-9.9). CLINICAL IMPLICATIONS: Propofol is a lipid-based emulsion capable of supporting microbial growth. Administration of a potentially contaminated solution may contribute to surgical wound infection or other patient morbidity or mortality. Strict aseptic technique in the preparation of the solution and prompt disposal of unused drug are imperative to curtail the potential for extrinsic contamination.     

Treatment of infected wounds and abscesses in bovine limbs with Ligasano-polyurethane-soft foam dressing material

The objective of this report is to present the most important indications for the use of Ligasano-polyurethane-soft-foam dressing material in the treatment of infected wounds in cattle. For this study, 28 cattle were selected, which were treated at the clinic (2000-2003) for infected cut, puncture and laceration wounds on the limbs, purulent tarsal hygromas, large abscesses in the tarsal, crural and thigh regions, and purulent tenosynovitis of the digital flexor tendon sheath caused by penetrating puncture wounds. After routine wound cleansing, debridement or adequate surgery with wound lavage, Ligasano-polyurethane-soft-foam (Ligamed Medical Produkte, Cadolzburg-Wachendorf, Germany) was applied as a primary wound dressing instead of the conventional cotton gauze swabs or as drainage material in all these wounds. The porous surface structure of this material caused subtle wound debridement and mechanical stimulation of the wound surface increasing exudation and decreasing fibrinous adhesions. The pores ensured good drainage, reduced infection, avoided the accumulation of exudate and the following destruction of the wound surface. In all these indications, except abscesses and purulent hygromas, no or only slight purulent exudation of the treated wounds was observed. Especially in the treatment of purulent tenosynovitis of the digital flexor tendon sheath with tendon resection a rapid healing of these large surgical wounds--often within 2 weeks--was found. The therapeutic effect of Ligasano-polyurethane-soft-foam as a primary wound dressing was so convincing in these bovine patients, that it is now used exclusively as primary wound dressing material for treatment of infected wounds.     

Topical and systemic medications for wounds.

There are a plethora of topical and systemic medications available to the veterinary practitioner today that aid the wound healing process. Some of these help to maintain a moist environment. Others increase growth factors, provide local energy sources, control infection, provide for debridement, increase wound blood flow and temperature, or reduce wound edema. Modern wound care requires that the proper products(s)be used, depending on the condition of the wound and the phase of wound healing. This article discusses various wound care products and provides guidelines on their use.     

Antimicrobial prophylaxis in canine surgery

In 1961, Burke showed that antibiotics affect primary wound infections favourably only if they are administered before or shortly after bacterial contamination. The effect is optimal if there is already an effective tissue concentration at the time of contamination. During surgery the animal's resistance is strongly reduced, and consequently an infection may be caused by an inoculum present in a rather low concentration, at least lower than in normal circumstances. This reduced resistance lasts until only a few hours after operation. Prophylactic use of antibiotics therefore needs to be continued only for a short time after the final stage of the operation. A great number of clinical trials in human surgery have shown that short term peri-operative prophylactic use of antibiotics causes a reduction in the incidence of post-operative septic complications, in certain categories of operations and in selected groups of patients. Until properly designed, prospective, randomized and controlled clinical trials have been done in small animal clinics, it seems sensible to apply the abundant results from research with experimental animals and from clinical trials in human medicine to small animal surgery. Prophylactic use of antibiotics is indicated if the infection risks or dangers of possible complications are greater than the disadvantages of regular use of antibiotics. The risk factors in the development of wound infections and the choice of antibiotics are discussed.     

Wound management in teleost fish: biology of the healing process, evaluation, and treatment.

Wound healing, although similar to terrestrial vertebrates, occurs faster in fish species in a proper aquatic environment. Wound management must involve identification and correction of potential noninfectious and/or infectious causes of disease. Wound evaluation includes assessment of the wound as well as systematic examination of the patient, water quality conditions, and husbandry practices. Diagnostic evaluation should, at a minimum, include physical examination, skin/cornea (if indicated) scraping, and lesions cultures. The clinician should also consider full thickness wound biopsies, gill and fin biopsies, blood collection, and radiographs for systemic evaluation as well. Local wound management should follow basic principles of wound care including cleaning and lavage, debridement, primary closure if indicated, and local and/or systemic antiinfectives. Monofilament absorbable or nonabsorbable sutures are commonly used for primary closure of wounds. Diagnostic results, patient and client compliance, and economic impact should guide systemic methods of treatment for wound care. Options for systemic therapy include oral or gavage, parenteral, bath, or prolonged immersion treatments. With bath or prolonged immersion therapies, aquatic systems must be properly prepared for treatment. Treatment of identified pathogens, proper water quality and husbandry, supportive care and nutrition must all be provided to promote an ideal wound healing environment for the teleost fish.     

Treatment of chronic septic osteoarthritis of the antebrachiocarpal joint with a synovial‐cutaneous fistula utilising arthroscopic lavage combined with ultrasonic assisted wound therapy and vacuum assisted closure with a novel wound lavage system

This case report describes the successful management of a chronic multidrug resistant infection of the antebrachiocarpal joint with a synovial‐cutaneous fistula 7 weeks after initial trauma in a 14‐year‐old Icelandic stallion. Resolution of the multiresistant Enterobacter cloacae (extended‐spectrum β‐lactamase) infection from the joint and complete closure of the fistula was achieved by arthroscopic lavage under general anaesthesia repeated on 3 occasions, surgical debridement, ultrasound assisted wound therapy and vacuum assisted closure. Lavage of the wound with the vacuum assisted closure in place was facilitated via the novel VeraFlo instillation system consisting of specially designed therapeutic regulated accurate care pad tubing. The combination of these therapies resulted in resolution of the septic arthritis and fistula. Six weeks after admission the horse was discharged from the hospital with a completely healed wound and was not lame at a walk.     

Clinical evaluation of axial pattern skin flaps in dogs and cats: 19 cases (1981-1990).

Nineteen axial pattern skin flaps were used in 16 dogs and cats to provide skin for repair of extensive cutaneous defects. Retrospective evaluation of medical records was used to determine percentage flap survival, postoperative complications, and long-term outcome of axial pattern skin flaps. The most common indication for use of axial pattern flaps was to augment wound closure following tumor resection (n = 7). Other indications included trauma (n = 5), chronic nonhealing wounds (n = 4), urine-induced cellulitis (n = 1), idiopathic dermal necrosis (n = 1), and chronic lymphoplasmocytic dermatitis (n = 1). Mean flap survival (+/- SD) was 96% (+/- 8). Postoperative complications included wound drainage (n = 15), partial dehiscence of the sutured flap (n = 7), distal flap necrosis (n = 6), infection (n = 3), edema (n = 3), and seroma formation (n = 2). After a median follow-up time of 5 months, evaluation of animals indicated that surgery provided successful wound reconstruction with good cosmetic results. Reconstruction of large cutaneous defects is facilitated by axial pattern flap application regardless of cause of wound. Postoperative complications are common but amenable to standard wound management techniques such as drain placement and surgical debridement of devitalized distal flap skin.     

Intracranial empyema: literature review and two novel cases in cats

OBJECTIVES: To review the literature on intracranial empyema and report two new cases in cats. METHODS: Literature review and case reports. RESULTS: Intracranial empyema has been rarely reported in small animals. In two novel cases in cats, the route of infection was postulated to be local extension from a retrobulbar abscess of odontogenic origin in one case and direct inoculation from a penetrating bite wound to the skull, confirmed at post-mortem examination, in the other. On magnetic resonance imaging of the first case, there was a contrast-enhancing large extra-axial fluid collection overlying the right cerebral hemisphere, consistent with subdural empyema. Infection was caused by an Actinomyces spp. This is the first report of successful treatment of intracranial empyema by craniotomy, drainage and antibiotics. CLINICAL SIGNIFICANCE: Intracranial empyema is a neurosurgical emergency. Favourable outcomes may be achieved with surgical decompression, antimicrobial therapy and intensive care.     

An overview of the topical management of wounds

Wounds in animals are a common and frequent reason for seeking veterinary attention. The way in which wounds are managed affect the rate of healing, the time to return to normal function, the final cosmetic appearance, and hence the satisfaction of customers. The management of wounds depends on the stage of wound healing and can include irrigation, mechanical and chemical debridement, the use of antiseptics and antimicrobials, adherent and nonadherent dressings, and miscellaneous topical applications such as aloe vera, honey and live yeast cell derivative. The advantages, disadvantages and indications for initial wound management, topical applicants and dressings are discussed.     

Lactate in veterinary critical care: pathophysiology and management

The measurement of blood lactate in people has proven to be a useful tool in the diagnosis, monitoring, and prognosis of a wide range of clinical syndromes. Its use in small animals is increasing, and several studies have been completed that demonstrate its potential role in critical care. This article summarizes the current state of knowledge regarding the physiology and pathophysiology of lactate production and lactic acidosis; current indications and the utility of measurement in a critical care setting are described; novel applications in the evaluation of cavitary effusions are highlighted; and a guide to the therapy of lactic acidosis is presented.     

Spontaneous chronic corneal epithelial defects in dogs: a review

Spontaneous chronic corneal epithelial defects (SCCEDs) in dogs are typically found in middle-aged dogs of all breeds. These epithelial defects may be present for weeks to months, particularly if left untreated or if treated inappropriately. Typical histopathological findings include loss of the corneal epithelial basement membrane and formation of a superficial, acellular, hyalinized zone in the stroma. Together, these histological abnormalities lead to delayed wound healing and poor epithelial adhesion. Epithelial debridement, anterior stromal puncture, grid keratotomy, and superficial keratectomy are the most common treatment options applied to the defects. Procedures that address the stromal changes present generally have a higher success rate than epithelial debridement alone.     

Methicillin‐resistant Staphylococcus aureus in Resident Animals of a Long‐term Care Facility

Animals provide benefits to elderly and chronically ill people by decreasing loneliness, increasing social interactions, and improving mental health. As a result, many hospitals and long‐term care facilities allow family pets to visit ill or convalescing patients or support animal‐assisted therapy programs. These include programs that have resident animals in long‐term care facilities. Despite the benefits, there are concerns about disease transmission between pets and patients. Antibiotic‐resistant bacteria, such as methicillin‐resistant Staphylococcus aureus (MRSA), are a recognized problem in healthcare settings leading to refractory infections and potentially life‐threatening illnesses. MRSA has been isolated from numerous animal species, yet few studies are available on the carriage of this pathogen in animals residing in long‐term care facilities. Our objective was to characterize MRSA carriage among resident animals in a long‐term care facility. Methods: To document MRSA colonization, nasal swabs from 12 resident animals (one dogs and 11 cats) of a long‐term care facility were collected weekly for 8 weeks. Staphylococcus isolates were characterized by antimicrobial susceptibility and MRSA isolates were further characterized by pulsed‐field gel electrophoresis (PFGE). PFGE isolate patterns were compared with an existing database of MRSA isolate patterns at the Minnesota Department of Health. Results: Two of 11 cats were colonized with MRSA. MRSA was recovered from five of eight weekly samples in one cat and two of eight weekly samples in the other cat. All isolates were classified as USA100 (healthcare‐associated strains). Discussion: Long‐term care resident animals may acquire MRSA. Clonally related strains were identified over the 8‐week sampling period. It is unclear if pets serve as an on‐going source of infection to their human companions in long‐term care facilities.     

The use of negative pressure wound therapy following subcarapacial abscess excision in a tortoise

A 42‐year‐old female Testudo graeca was referred with a five‐month history of a non‐healing carapacial wound. Previous treatment had involved long‐term antibiotic therapy and conscious debridement of necrotic tissue. On presentation an extensive deep wound with purulent discharge was visible on the right side of the carapace. A computed tomographic scan was performed to assess the extent of the wound. This revealed a large carapacial deficit with two underlying soft tissue masses. Surgical debridement was performed under general anaesthesia resulting in an even larger defect. Because of the extensive nature of the deficit, negative pressure wound therapy was applied to aid wound healing. A negative pressure of approximately 120 mmHg was maintained and bandages were changed every third day. Wound healing progressed rapidly and a healthy granulation bed was formed within 16 days.     

Management of traumatic fistulous withers and wounds of the lumbar dorsal spinous processes of horses and donkeys used for pack animals

Over a three year period, eighty-nine (89) traumatically induced wounds on the withers and lumbar area of donkeys and horses were treated by the ambulatory clinic at Universidad Nacional Autónoma de México. The wounds generally resulted from poorly fitting pack equipment. Treatment regimens were divided into two categories: 1) conservative topical therapy plus padding or 2) surgical debridement and primary wound closure. Conservative therapy with topical medications and padding was successful in many cases in spite of the fact that the animals generally continued working. However, recurrence of lesions following conservative therapy was common. Surgical treatment was used primarily in cases refractory to conservative therapy. As a result of surgical intervention, clients tended to comply with recommendations to stop working the animal. The convalescent time was shorter, and the recurrence rate was lower following surgery than for conservative therapy.     

Botulism as a sequel to open castration in a horse

Clostridium botulinum and type-B C botulinum toxin were isolated from a necrotic wound that developed subsequent to castration in a 2-year-old Thoroughbred gelding. The horse had clinical signs of botulism and was successfully treated with wound debridement, C botulinum type-B antitoxin, potassium penicillin, and supportive care.     

Second-intention healing

Second-intention healing (contraction and epithelization) is most appropriate for heavily traumatized, contaminated wounds that may have a prolonged debridement phase. Therapy during healing can promote rapid debridement and faster healing. Healing of lower limb wounds by second intention may be protracted, owing to poorer wound contraction and excessive granulation tissue production as compared with body wounds.     

Hoof injuries

Major surgery for wounds of the foot, compared with other parts of the body, requires a more detailed preparation and a more persistent aftercare. To approach severe hoof wounds with a routine applicable to drainage of a subsolar abscess is doomed to failure! Yet, in dealing with referral cases of hoof wounds, particularly those that have become chronic, the author has observed that the principles have been ignored and/or the routines inadequate. The hoof has a suitable capacity to heal, with complete reformation of hoof structures, if a healing environment is maintained for a long enough period of time. For severe wounds, such time must be measured in months. A lack of attentiveness to the principles of hoof wound care and impatience during convalescence are the reasons for persistent lameness or for the formation of chronic hoof defects. The amount of hoof loss or the presence of distal phalangeal and/or deep digital flexor tendon exposure are not limiting factors to a successful outcome. Also, the initial assessment of the wound may not present an accurate picture of the eventual outcome. Both the veterinarian and the client may need to be committed to the horse's care for weeks or months before the final result is apparent; however, experience and faithful commitment help to avoid misjudgments in the selection of cases for follow-through. After healing, the resultant hoof frequently has far less functional or cosmetic impairment than might seem apparent at the outset. Most hoof wounds respond to proper therapy and recover without a hoof wall defect. The time lapse between injury and definitive care is critical. The amount of hoof loss and the exposure of deep foot structures are less critical. Such cases should be handled as a high priority, if not on an emergency basis. Prolonged delay is to be feared; contamination becomes infection, which extends, over time, to deeper, vital structures of the foot, with an unfavorable impact on the prognosis. Deep, penetrating wounds that invade the podotrochlea require early, even emergency, attention in order to avoid permanent debility, mortality, or euthanasia.     

Corneal fungal disease in small animals

Corneal fungal diseases, including fungal keratitis and stromal abscess, are uncommon in small animals. Ocular infection secondary to systemic mycosis is reported far more frequently. Suspicion of a fungal corneal ulcer should be raised based on a history of underlying trauma, especially with plant material, geographic location, chronic use of topical antibiotics or corticosteroids, or an extremely prolonged course of disease despite appropriate treatment. Clinical signs observed with fungal keratitis may include blepharospasm, epiphora, miosis, corneal opacity, and vascularization. Unfortunately, none of these signs is specific to fungal infection. If fungal keratitis is suspected or confirmed, then aggressive medical therapy should be instituted. Medications used include topical antifungals, parasympatholytics, anticollagenases, and antibacterials as well as systemic anti-inflammatory drugs. Because there are very few fungicidal medications, the course of medical treatment for fungal corneal disease requires a prolonged duration with frequent re-examination and assessment. Surgical treatment is sometimes required to save the eye and vision. Surgeries to be considered include debridement, conjunctival graft placement, and corneal transplantation.