Wounds associated with osseous sequestration and penetrating foreign bodies

Nonhealing wounds can present a frustrating clinical challenge to the veterinary practitioner. In many cases, healing is delayed by the presence of a foreign body or sequestrum; a review of wounds complicated by the presence of osseous sequestration and penetrating foreign bodies is presented. The typical signs include delayed wound healing and the presence of serous to exudative drainage, which may vary from intermittent to continuous. The use of radiographic or sonographic imaging modalities is often of value in reaching a diagnosis. Removal of the sequestra or foreign body is generally curative.     

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.     

Ferrets: wound healing and therapy.

In all species of mammals, the stages of wound healing are the same, and both host factors and wound characteristics affect how wounds heal. The basic principles of wound care in ferrets, such as lavage, bandaging, and surgical closure, are similar to those in other species; however, knowledge of ferrets' anatomy and pathophysiology, as well as skin conditions commonly seen in ferrets, will help ensure proper wound healing.     

A Novel Bioelectric Device Enhances Wound Healing: An Equine Case Series

The use of low-level microcurrents for accelerated wound healing is well documented. A case series was conducted to assess wound healing outcomes following the application of a wireless, current-generating bioelectric wound care device in 10 equines that presented with traumatic injuries in the lower extremity. Wounds were treated with a bioelectric device held in place with standard bandaging twice a week. At each follow-up visit, wounds were photographed and assessed for signs of epithelialization. All presented wounds were reduced in size or achieved complete wound closure, with an average 1.3% wound healing per day. The results of this case series demonstrate the safety and efficacy of a bioelectric device as a management option for traumatic lower-extremity wounds in equines and hold significant promise in promoting enhanced healing rates and improved aesthetic outcomes.     

Large trunk wounds.

Management of large trunk wounds begins with good wound management and bandaging. When a healthy wound bed exists and adequate tissue is present, the wound is closed. Fortunately, there is an abundance of loose trunk skin in most animals, and wound closure can be accomplished by simple reconstructive techniques, such as undermining and tension or "walking sutures." Nevertheless, some wounds and areas of the torso may require more advanced tension-relieving techniques, skin stretching, and tissue implants or flaps to achieve tension-free closure and successful wound healing. Use of these techniques allows wound closure and good cosmetic results for even those wounds that initially may seem foreboding.     

CLINICAL TECHNIQUE: Negative Pressure Wound Therapy-General Principles and Use in Avian Species

Negative pressure wound therapy (NPWT) is an adjunctive wound management modality that has been shown to augment the treatment of acute and chronic dermal and subdermal wounds in human and veterinary medicine. The proposed effects of NPWT are multifactorial and include improvement of wound perfusion, reduction of interstitial edema and substances inhibitory to wound healing, enhancement of granulation tissue formation, and reduction in bacterial contamination from a wound bed. Together, the proposed benefits of NWPT can lead to enhanced efficiency of wound healing when this treatment modality is applied to a wound. In this article, the authors provide an overview of the mechanism of action of NPWT. Case selection, system application and management, as well as contraindications to NPWT therapy are presented. Potential uses, practical application, and limitations of use of NPWT in avian species are discussed.     

Evidence-based wound management: a systematic review of therapeutic agents to enhance granulation and epithelialization.

Successful management of open wounds in dogs requires knowledge of the physiology of wound healing and application of that knowledge to choose appropriate therapeutic intervention. The authors' objective was to investigate whether or not there are any available therapeutic agents that enhance granulation or epithelialization of open wounds in dogs. Based on the literature identified in the authors' review, there is insufficient evidence to make a recommendation for or against any of the topical wound agents or procedures studied.     

The pathophysiology of wound repair.

The equine practitioner who is presented with a wounded horse should fully understand the physiologic mechanisms involved in repair so as to design an appropriate treatment plan. In the following articles of this issue,experienced authors share their thoughts on the management of specific injuries, and the reader should benefit from acquisition of knowledge about the different phases of healing as well as the cytokines that regulate them,because these data dictate the approach to follow, particularly in com-plicated wounds, such as those afflicted by chronic inflammation and/or an excessive proliferative response.     

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.     

Wound healing and management in psittacine birds.

Psittacines and other companion avian species often develop wounds requiring some form of medical or surgical therapy. Advancing technology in the field of wound care and management continues to evolve for use by the veterinary clinician. Although not all wounds can be successfully treated, many can be reduced and minimized with therapy. Consideration of the overall health, management, and nutrition of the avian patient will also aid in wound management. The avian patient with normal immune function and optimal nutrition will have improved wound healing compared with an immunocompromized or malnourished patient. The duration of treatment and potential stress of the wound-management program should also be taken into consideration when selecting a treatment program for the avian patient.     

Management of hard-to-heal wounds.

Some wounds do not heal normally and present the practitioner with a challenge. These can be thought of as hard-to-heal wounds. There are numerous causes of such wounds, and when they occur, the veterinarian should consider all factors associated with the wound. When diagnostic tests are indicated, they should be performed. Finally, appropriate measures should be taken to correct the underlying cause of the hard-to-heal wound.     

Cutaneous wound healing in the cat: a macroscopic description and comparison with cutaneous wound healing in the dog

OBJECTIVE: To describe the macroscopic features of first and second intention cutaneous wound healing in the cat and compare with the dog. STUDY DESIGN: Experimental study. ANIMALS: Domestic shorthaired cats (6) and beagle dogs (6). METHODS: Square, open cutaneous wounds created on the dorsal aspect of the thorax were evaluated for 21 days for temporal and spatial development of granulation tissue, wound contraction, epithelialization, and total healing. To evaluate first intention healing, breaking strength of sutured linear cutaneous wounds was measured at 7 days post-wounding. Laser-Doppler perfusion imaging was used to measure cutaneous perfusion. RESULTS: First intention healing: sutured wounds in cats were only half as strong as those in dogs at day 7 (0.406 versus 0.818 kg breaking strength). Second intention healing: cats produced significantly less granulation tissue than dogs, with a peripheral, rather than central distribution. Wound epithelialization and total wound healing (total reduction in open wound area from contraction and epithelialization) were greater for dogs than for cats over 21 days. Wound contraction on day 7 was greater for dogs, but not on day 14 or 21. Cutaneous perfusion was initially greater for dogs than for cats, but no differences were detected after day 7. CONCLUSIONS: Significant, previously unreported differences in cutaneous wound healing exist between cats and dogs. In general, cutaneous wounds in cats are slower to heal. Cats and dogs also appear to use different mechanisms of second intention healing. In cats wounds close mainly by contraction of the wound edges, whereas in dogs wounds close more from central pull, and epithelialization. CLINICAL RELEVANCE: Surgeons should view the cat as a unique species, which presents its own special challenges in wound healing, and should take this into account when planning treatment of feline wounds, either by primary closure, or by second intention healing.     

Wound management in reptiles.

Our understanding into the healing response of reptile wounds is in its infancy. To date, many of the methods we have used have been adopted from human, mammalian, or avian species, with varying success. Future research should focus on the development of methods to improve our management of contaminated wounds, minimize the negative inflammatory responses occurring in a wound, and shorten wound-healing time.     

Microbiology of equine wounds and evidence of bacterial biofilms

Horse wounds have a high risk of becoming infected due to their environment. Infected wounds harbour diverse populations of microorganisms, however in some cases these microorganisms can be difficult to identify and fail to respond to antibiotic treatment, resulting in chronic non-healing wounds. In human wounds this has been attributed to the ability of bacteria to survive in a biofilm phenotypic state. Biofilms are known to delay wound healing, principally due to their recalcitrance towards antimicrobial therapies and components of the innate immune response. This study describes the presence of bacterial biofilms within equine wounds. Thirteen 8-mm diameter tissue samples were collected from (n=18) chronic wounds. Following histological staining, samples were observed for evidence of biofilms. Fifty one wounds and control skin sites were sampled using sterile swabs. Control skin sites were on the uninjured side of the horse at the same anatomical location as the wound. The isolated bacteria were cultured aerobically and anaerobically. The biofilm forming potential of all the isolated bacteria was determined using a standard crystal violet microtitre plate assay. Stained tissue samples provided evidence of biofilms within 61.5% (8 out of 13) equine wounds. In total 340 bacterial isolates were identified from all the equine wound and skin samples. Pseudomonas aeruginosa and Enterococcus faecium were the most predominantly isolated bacterial species from equine wound and skin samples respectively. Staphylococcus was the most commonly isolated genus in both environments. Bacteria cultured from chronic and acute wounds showed significantly (P<0.05) higher biofilm forming potential than bacteria isolated from skin. This paper highlights preliminary evidence supporting the presence of biofilms and a high microbial diversity in equine chronic wounds. The presence of biofilms in equine wounds partly explains the reluctance of many lower limb wounds to heal. Non-healing limb wounds in horses are a well documented welfare and economic concern. This knowledge can be used to shape future treatments in order to increase the healing rate and decrease the costs and suffering associate with equine wounds.     

Effects of topical application of taurolidine on second intention healing of experimentally induced wounds in rats

OBJECTIVE: To determine the macroscopic effects of topical application of taurolidine on second intention healing of experimentally induced wounds in rats. ANIMALS: 32 adult Sprague-Dawley female rats. PROCEDURES: In each rat, 2 skin wounds were created in the lumbar area. Groups of 7 rats were assigned to have 1 wound treated topically with hydroxycellulose gel (HDCG), 2% taurolidine in HDCG (T-HDCG), 2% taurolidine-sodium citrate solution, or bacitracin-neomycin-polymyxin B ointment; the other wound was not treated. Four control rats (8 untreated wounds) were used. Wounds were monitored for contraction, epithelialization, and complete healing at 4, 8, and 14 days after wound creation. The number of days to complete healing was also recorded for each wound. RESULTS: Compared with other treatments or untreated wounds, wounds treated with T-HDCG had decreased total healing at day 8 and decreased epithelialization and decreased total healing at day 14. Wounds treated with T-HDCG required approximately 3 days longer to completely heal than all other treated and untreated wounds. Application of bacitracinneomycin-polymyxin B ointment did not enhance wound healing. Mean time to complete healing of untreated wounds in all treatment and control groups was 10.00 to 10.14 days. CONCLUSIONS AND CLINICAL RELEVANCE: In rats, topical application of T-HDCG to wounds had a negative effect on second intention healing by delaying the epithelialization process. In mammals, generally, wounds treated topically with taurolidine may need to be treated and monitored for a longer period than other wounds treated with other common woundhealing compounds or untreated wounds.     

Evaluation in vivo and in vitro of the performance of interactive dressings in the management of animal soft tissue injuries

Over the last 35 years there has been extensive research into human wounds and consequent evolutionary changes in their management. Products such as vapour-permeable films, alginates, hydro-colloids, hydrogels and foams have been developed, all of which contribute in different ways to the enhance-ment of the healing cascade. The first part of this study assessed the influence on animal wound healing of some of these contemporary wound-management products
  With animal wounds the major problem is their isolation from the aggression of both the patient and the environment. The second part of this paper is directed at the development of an occlusive chamber to enable topically applied medicaments to remain in contact with the wound surface and presents the initial results of a programme of investigation directed at producing a 'ring' adhesive to overcome the adherence problems presented by lipid concentration and hirsutism. This adhesive also allows successive applications of contemporary dressings.     

Effects of 3 biologic dressings on healing of cutaneous wounds on the limbs of horses

Three biologic dressings [split-thickness allogeneic skin (STS)], allogeneic peritoneum (P), and xenogenic porcine small intestinal submucosa (PSIS)] were studied to determine their effects on bacterial proliferation, inflammatory reaction, vascularization, and overall healing and to compare the effects of these dressings with the effects of a nonbiologic dressing, a nonadherent synthetic pad (NASP). A medial wound (3 cm in diameter) and 2 lateral wounds (2 cm in diameter) were created at the junction of the proximal and middle thirds of each metacarpus and metatarsus in 5 horses. Each medial wound and the proximolateral wound received an STS, P, PSIS, or NASP dressing on day 8 after wounding. The other lateral wound received an NASP dressing. Bacterial proliferation, inflammatory reaction (histologic changes), and drhessing vascularization were evaluated 6 d after application of the dressing. Percentages of contraction and epithelialization, as well as healing time, were determined when the wounds had completely epithelialized. The practical applicability of the different dressings to equine wound management was also assessed. No significant difference was detected in the parameters evaluated among the treated wounds or between the treated and control wounds. The biologic dressings had no effect on infection, inflammatory response, or healing time. Vascularization was not identified in any of the biologic dressings. The PSIS and P dressings required numerous applications over the study period. The STS dressings are more practical than PSIS and P dressings owing to ease of application and stability. Thus, these biologic dressings offer no apparent advantage over a nonbiologic dressing for treatment of small granulating wounds.     

Wound management in rodents.

Successful wound management requires appropriate evaluation of the wound at the time of initial physical examination, an all throughout the healing process. Factors affecting wound healing need to be identified though a complete patient history and addressed to ensure proper healing. The clinician must have current knowledge of topical medications and bandages available and their clinical applications according to the stage of healing. It is essential to remember that wounds are painful; therefore, analgesics should be administered to render the animal pain-free during wound cleaning, debridement, bandaging, and surgical procedures.     

Effect of wound location and the use of topical collagen gel on exuberant granulation tissue formation and wound healing in the horse and pony

Preformed collagen gel was topically applied to cutaneous wounds of the equine dorsal fetlock (thoracic limb) and metatarsal regions to evaluate the effect on exuberant granulation tissue production and wound healing. In 6 horses and 3 ponies (less than 140 cm high at the withers and less than 365 kg), 36 standardized cutaneous limb wounds were surgically induced (4 wounds/animal); 18 wounds were treated topically with collagen gel, and 18 wounds were not treated (controls). Collagen gel was initially applied to the wound at 0, 2, or 7 days after wound formation (groups 1, 2, and 3, respectively). Four measurements were regularly made: amount of wound contraction and the size of the granulation bed, epithelial covering, and total wound. Sequential skin and wound biopsies were evaluated histologically to assess wound healing. Using a computer, data were analyzed for differences in the 4 measurements between treated and control wounds, between fetlock wounds and metatarsal wounds, and among groups 1, 2, and 3. Analyses were performed on days 15 and 45 of wound healing and on the final day of healing. A significant difference (P greater than 0.05) in the production of exuberant granulation tissue, rate of epithelialization, or degree of wound contraction was not detected between the collagen-treated and control wounds. Total healing time and final scar size were similar. Wound healing patterns were significantly different (P less than 0.05) in the fetlock wounds and metatarsal wounds. All wounds enlarged up to day 15 with fetlock wounds enlarging significantly more than did the metatarsal wounds.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effect of autologous platelet-rich plasma application on cutaneous wound healing in dogs

This study was conducted to identify the effectiveness of platelet-rich plasma (PRP) and efficacy of intralesional injection as a method of application to acute cutaneous wounds in dogs. Healthy adult beagles (n = 3) were used in this study. Autologous PRP was separated from anticoagulant treated whole blood in three dogs. Cutaneous wounds were created and then treated by intralesional injection of PRP in the experimental group, while they were treated with saline in the control group on days 0, 2 and 4. The healing process was evaluated by gross examination throughout the experimental period and histologic examination on day 7, 14 and 21. In PRP treated wounds, the mean diameter was smaller and the wound closure rate was higher than in the control. Histological study revealed that PRP treated wounds showed more granulation formation and angiogenesis on day 7, and faster epithelialization, more granulation formation and collagen deposition were observed on day 14 than in control wounds. On day 21, collagen deposition and epithelialization were enhanced in PRP treated groups. Overall, PRP application showed beneficial effects in wound healing, and intralesional injection was useful for application of PRP and could be a good therapeutic option for wound management in dogs.