Comparison of the Role of the Subcutaneous Tissues in Cutaneous Wound Healing in the Dog and Cat

NOVEL USE OF NILE TILAPIA FISH (OREOCHROMIS NILOTICUS) SKIN AS XENOGRAFT IN ZOOLOGICAL SPECIES

Nile tilapia fish skin (Oreochromis niloticus) has been increasingly used in human and veterinary medicine in xenografts for treatment of burn wounds. The objective of this study was to self-prepare the graft using a Brazilian patent (WO2017/035615 A1) as a guide and apply it to full-thickness wounds in zoological species (n = 4). The wounds, which were all characterized as contaminated wounds in which the entire dermal layer was missing, had all previously been surgically debrided and treated with traditional wound-healing techniques without success. This graft technique was developed in response to the poor treatment success. The graft was prepared and sutured to the affected area, leading to complete contraction and epithelialization in all cases. The patients were concurrently placed on one course of systemic antibiotics because of the severity of wound contamination. The frequency of dressing changes varied between species and no adverse effects were apparent. This method of processing Nile tilapia fish skin proves promising for use in contaminated wounds, as it is inexpensive and easy to acquire and develop, mitigates stress in wildlife patients because of a decreased frequency of dressing changes and therefore handling, and can be utilized in clinical environments.

Insights into Atresia Ani Type IV in Felis catus: Preliminary Epidemiolocal Findings Associated with Surgery

Atresia Ani (AA) is a rare congenital anomaly in companion animals affecting rectal and anal development. Its incidence in cats remains unreported. This retrospective study aimed to characterize age, body condition, fistula size, and perioperative outcomes in Type IV Atresia Ani (with recto-vaginal fistula) in female cats. Surgical intervention is the primary treatment. Conducted over 2 years, the study included nine female cats diagnosed with Type IV Atresia Ani and recto-vaginal fistula undergoing surgery. Statistical analysis used the R program (version 4.2.1) with Rstudio®® extension. Significant results were observed at a 95% confidence interval and p < 0.05. The condition had an incidence of 4.7% among the 192 cats evaluated over a 2-year period. The findings suggest that a body condition score of 3, an age of 3 to 4 weeks, and a fistula length of 1 to 2 mm correlated with better surgical outcomes, reducing the likelihood of fecal incontinence and anal stenosis development, and enhancing defecation awareness during the perioperative period. This study is the first to report the disease incidence in cats undergoing surgery, according to the authors' knowledge.

Complications and influence of cutaneous closure technique on subdermal plexus flaps in 97 dogs (2006-2022)

OBJECTIVE

To determine the incidence and severity of complications for subdermal plexus flaps in dogs and compare the complications when using sutures or staples for cutaneous closure of subdermal plexus flaps.

STUDY DESIGN

Retrospective monocentric study.

SAMPLE POPULATION

Ninety-seven client-owned dogs.

METHODS

Dogs that underwent wound reconstruction using subdermal plexus flaps were retrospectively identified. Type of flap, cutaneous closure technique, complications and level of complication associated with their use were recorded. Follow-up was considered adequate if it was more than 10 days postoperatively or until a complication occurred.

RESULTS

Complications were seen in 52 dogs (53.6%), of which 13/18 (72.2%) of dogs had cutaneous closure with skin staples versus 39/79 (49.3%) with skin sutures. The location of the mass/wound on the head and use of an advancement flap was associated with lower incidence of complications (p < .001; p = .018 respectively). Location of the mass/wound on the proximal pelvic limb was associated with a low level of complications (p = .01) on univariable analysis only. On multivariable analysis, only an increased bodyweight was associated with an increased incidence of complications (p = .029).

CONCLUSIONS

Increased weight may be associated with an increased risk of complications with subdermal plexus flaps. No risk factor was found to be associated with the severity of complications.

CLINICAL SIGNIFICANCE

Overall incidence of complications for subdermal plexus flaps in dogs in this study was 53.6%. The number of dogs included in the study was not sufficient to assess if the skin closure technique affects the incidence of complications.

First-Intention Incisional Wound Healing in Dogs and Cats: A Controlled Trial of Dermapliq and Manuka Honey

This study aimed to compare incisional wound healing in cats and dogs after the topical application of Μanuka honey and a new medical device, Dermapliq. Comparisons were made between each treatment and control, between the two treatments, and between dogs and cats. Twelve cats and twelve dogs were included in this study, and the impact of the two substances was examined through cosmetic, clinical, ultrasonographical, and histological evaluation. The use of Dermapliq in first-intention wound healing achieved a significantly better cosmetic evaluation score and better total clinical score at days 20-41, compared to the control, in both dogs and cats. The ultrasonographically estimated wound area was smaller with Dermapliq compared to the control. Wounds treated with Dermapliq showed histologically less inflammation compared to the control. The use of Manuka honey did not show a significantly better cosmetic score compared to the control. Skin thickening was significantly higher after using Manuka honey compared to the control and so was the total clinical score. However, the median wound area, as was evaluated ultrasonographically, was significantly smaller when wounds were treated with Manuka honey, the difference being more apparent in dogs. Dermapliq was proven to be a better choice in achieving favorable wound healing than Manuka honey in dogs and cats in first-intention healing. In our study, cats had a statistically better cosmetic score and less skin thickening and scar width compared to dogs. Histologically, cats showed significantly less edema, higher inflammation and angiogenesis scores, and lower fibroblast and epidermis thickening scores when compared to dogs.

Evaluation of the Effectiveness of Medical-Grade Honey and Hypericum Perforatum Ointment on Second-Intention Healing of Full-Thickness Skin Wounds in Cats

This study aimed to determine the effects of two topical treatments on second-intention wound healing in cats. Eight 2 × 2 cm full-thickness wounds were created, four on each side of the dorsal midline of eight laboratory cats, to receive either medical-grade honey ointment (MGH) and its control (HC), or Hypericum-based ointment (HP) and its control (HPC). MGH or HP ointment was applied to four wounds on the same side, while the remaining four were used as controls, chosen at random. Planimetry, laser Doppler flowmetry, daily physical examinations, and histologic examinations on days 0, 7, 14, and 25 were used to assess the healing of wounds. Tissue perfusion was better in the MGH-treated (2.14 ± 0.18 mm/s) and HP-treated wounds (2.02 ± 0.13 mm/s) than in the untreated controls HC (1.59 ± 0.11 mm/s) and HPC (1.60 ± 0.05 mm/s), respectively (p = 0.001). Histopathology revealed that the median edema score was lower in the MGH-treated (2; range 1-4) compared to the HC-treated wounds (3; range 2-4) on day 7 (p < 0.05). The median angiogenesis score was higher on day 7 in the MGH-treated (2; range 1-3) compared to the HP-treated wounds (2; range 1-2) (p = 0.046). The fibroblast concentration was increased in the MGH-treated wounds (3.5; range 3-4) compared to the HP-treated wounds (3; range 2-4) on day 25 (p = 0.046). MGH and HP increased tissue perfusion compared to the untreated controls. The MGH-treated wounds had histologic parameters superior to the HP-treated wounds regarding angiogenesis and fibroblast concentration in cutaneous wound healing in cats. Topical application of MGH and HP did not accelerate the healing process of feline cutaneous wounds.

Comparison of Two Surgical Techniques Based on the Semitendinosus Myocutaneous Flap in Cats

The objective of this experimental study was to compare the semitendinosus (ST) to the split-semitendinosus (SST) myocutaneous flap in covering distal limb skin defects in cats. Twenty-eight purpose-bred laboratory DSH cats were used and allocated into two groups (ST-group (A); n = 14, SST-group (B); n = 14). ST flaps, based on the distal muscle pedicle, and SST flaps, after longitudinal division of the muscle based on both muscle pedicles, were tested over skin defects created on the medial distal tibia. Clinical assessment, planimetry, CT-angiography (CTA) and histological examination were compared between groups. Days to complete flap healing between ST and SST-flaps (30.36 ± 9.1, 32.29 ± 5.44, respectively) and final total flap areas (68.36% ± 27.18, 51.83% ± 22.48, respectively) revealed no significant differences. On CTAs, the caliber of the distal caudal femoral vein on day 10 was statistically significant higher (p < 0.001) for group A and a significantly higher caliber of the distal caudal femoral artery on day 30 for group B (p = 0.021). Histology revealed statistically higher degeneration at 6 months (p = 0.047) for group A, and statistically higher fibrosis at 12 months (p = 0.019) for group B. Both ST and SST flaps had similar healing times and provided coverage of skin tibial defects in cats.

Short-term outcome and complications following cutaneous reconstruction using cranial superficial epigastric axial pattern flaps in dogs: six cases (2008-2022)

OBJECTIVES

To investigate short-term outcome and complications following the use of the cranial superficial epigastric axial pattern flap to reconstruct cutaneous defects in dogs.

MATERIALS AND METHODS

Medical records from dogs undergoing reconstructive surgery between 2008 and 2022 by means of cranial superficial epigastric axial pattern flap were reviewed. Data on signalment, reason for reconstruction, defect size, flap healing, post-operative complications and need for revision surgery were collected.

RESULTS

Six dogs were included in the study. Indications for reconstruction included neoplasia (4/6), skin necrosis due to vehicular trauma (1/6) and dog bite (1/6). Postoperative complications occurred in 50% of the patients and included seroma (1/6), bruising (2/6) and necrosis of the distal portion of the flap (2/6), with two dogs developing concurrent complications. One dog required open wound management and additional surgery. Overall outcome was scored excellent in three, good in two, and fair in one dog.

CLINICAL SIGNIFICANCE

Despite the relatively high complication rate, most of the complications were deemed minor and could be managed conservatively. Eventually, all wounds healed completely and only one flap required revision surgery.

Clinical Evaluation of Medical Ozone Use in Domestic Feline Cutaneous Wounds-A Short Case Series

Support and management of second-intention wound healing involves frequent dressing changes having different properties. Dressings can range from simple ones, such as nonadherent dressings, to more complex options, such as foam, hydrocolloid, alginate or negative pressure dressings. Seven cats were enrolled in the study with a total of nine wounds of various sizes with different etiology sizes and localizations. Three methods of local ozone administration were used to cover more of the ozone properties in the treatment of wounds: bagging, perilesional subcutaneous infiltrations and lavages with ozonated saline. Evaluation of the healing process was performed by clinical observation and wound area measurements every seven days until the complete recovery of the patients. The results of this study should encourage clinicians to consider medical ozone as a new therapeutic approach with regenerative properties in the second-intention healing of cats presenting cutaneous wounds.

Characteristics, surgical treatment, and outcomes of injuries involving the tarsus in greyhounds

Objective

The first objective of this study was to describe the type of tarsal injuries sustained, surgery performed, and postoperative complications in greyhounds presenting to a single veterinary hospital. An additional objective of the study was to determine the surgical site infection (SSI) and explantation rate, and if any variables were associated with an increased risk of SSI and/or explantation.

Animals

116 greyhounds receiving surgical intervention for a tarsal injury.

Proceures

Medical records from a single veterinary referral hospital were reviewed retrospectively. Data retrieved included signalment, details regarding the injury, surgical intervention, concurrent castration, surgical/anesthesia times, postoperative management, time to healing, and postoperative complications. In cases that underwent explantation, cause, time from initial surgery, and risk factors were evaluated.

Results

The most frequently diagnosed tarsal injuries were fracture of the central tarsal bone (CTB; 57.8%), calcaneal fracture (56.9%) and proximal intertarsal subluxation (34.5%). The most common injury combination was a CTB fracture with a calcaneal fracture (31.9%). In total 115 (99.1%) survived to discharge. Of these, 46 (40.0%) were diagnosed with an SSI and 59 (51.3%) underwent explantation. The most common indication for explantation was SSI. Concurrent medial and lateral surgical approaches was found to be associated with an increased likelihood of SSI and explantation.

Clinical relevance

Practitioners performing surgical intervention for tarsal injuries in greyhounds should be aware of the high SSI rate and likelihood that explantation will be required. This risk is elevated for injuries requiring a bilateral surgical approach.

Combined Oxygen-Ozone Therapy for Mesh Skin Graft in a Cat with a Hindlimb Extensive Wound

This case report describes a new therapeutic approach for a domestic shorthaired female cat, who has an extensive posttraumatic wound in the right hind limb. After patient stabilization, general anesthesia was started and the wound was cleaned and debrided of devitalized tissues, followed by the application of ozone therapy and bandage. Eight sessions of ozone therapy were performed for 17 days until the application of the skin graft. Three more sessions of ozone therapy were performed every 3 days postoperatively. The bagging method and the perilesional infiltration method were used. The ozone therapy ensured an accelerated recovery of the patient without any complications. According to our knowledge, this is the first case report with the use of ozone therapy to support a free skin graft in a cat. The new therapeutic approach could be used to accelerate healing of the wounds with a significant lack of substance, by supporting pre- and post-operative skin grafts.

Use of a semitendinosus myocutaneous flap for the coverage of hindlimb full-thickness skin defects in cats

BACKGROUND

The management of feline hindlimb full-thickness skin defects is challenging. On the other hand, the use of a semitendinosus (ST) myocutaneous flap for their coverage has not been reported.

OBJECTIVES

To describe the ST flap and compare it with second intention healing for managing hindlimb full-thickness skin defects.

METHODS

In 12 purpose-bred laboratory domestic short-haired cats, two wounds were made on each tibia. The wounds in group A (n = 12) were covered with ST flaps, and those in group B (n = 12) were left to heal by second intention. In both groups, clinical assessment scoring and planimetry were performed between one-30 d postoperatively. Computed tomography-angiography (CTA) was performed on days zero, 10, and 30, and histological examinations were performed on days zero and 14 and at 6 and 12 mon postoperatively.

RESULTS

Statistically significant differences in the clinical assessment scores were observed between groups A and B on days 14 (p = 0.046) and 21 (p = 0.016). On the other hand, the time for complete healing was similar in the two groups. CTA revealed significant differences in the muscle width (day 0 compared to days 10 and 30 [p = 0.001, p = 0.026, respectively], and days 10 to 30 [p = 0.022]), ST muscle density, and the caliber of the distal caudal femoral artery and vein (day 0 compared to day 10 [p < 0.001], and days 10 to 30 [p < 0.001]). Histologically significant differences in inflammation, degeneration, edema, neovascularization, and fibrosis were observed on day 14 compared to zero and 6 mon, but no differences were found between the time interval of 6 and 12 mon.

CONCLUSIONS

An ST flap can be used effectively to manage hindlimb full-thickness skin defects.

Enhancement of chronic wound healing with maltodextrin/ascorbic acid gel: a clinical evaluation of distal limb wounds in horses

Delayed healing associated with distal limb wounds is highly challenging in equine clinical practice. This study aimed to evaluate healing rates between chronic non-granulating wounds of horse distal limbs that were treated with maltodextrin/ascorbic acid gel alone or in combination with povidone-iodine 1% solution and those treated with povidone-iodine 1% only throughout the study period (35 days) in clinical settings. The study was conducted on 18 adult horses (3-15 years old). Based on the treatment regimen utilized, the horses were divided into three groups (n = 6), with each group having a similar mean wound area. The percentages of wound contraction, epithelialization, and overall wound healing were determined weekly for each wound. By the end of the study, the total wound healing percentage was significantly increased between the study groups (p < 0.05). The use of maltodextrin/ascorbic acid gel resulted in considerable wound contraction, rapid epithelialization, and complication-free wound healing. Based on the findings of this study, maltodextrin/ascorbic acid gel, independently or in combination with a 1% povidone-iodine solution, might be applied as a safe and effective wound healing promoting agent in horses with chronic non-granulating wounds.

Locally Injected Autologous Platelet-Rich Plasma Improves Cutaneous Wound Healing in Cats

Cutaneous defects in cats are commonly encountered in clinical practice, and healing can be accomplished by first or second intention. Platelet-rich plasma (PRP) is characterized by a plasma concentration containing a large number of platelets in a small volume of plasma. The objective of the present study was to record the efficacy of PRP infiltration in open wounds in laboratory cats. Six wounds were created in the dorsal midline of eight laboratory cats, with the wounds of one side designated as the PRP group and the wounds of the other side as the control group. Wound healing was evaluated by daily clinical examination, planimetry, laser Doppler flowmetry, and histologic examination on days 0, 7, 14, and 25, and by measurement of metalloproteinases (MMPs)-2 and -9 and tissue inhibitor metalloproteinase (TIMP)-1 on days 0, 14, and 25. Based on the results of the present study, the mean time for full coverage with granulation tissue was shorter in the PRP group, the mean contraction and total wound healing percentage were increased compared to the control group, and finally, the perfusion measured with laser Doppler flowmetry was higher in the PRP group during all examination days. In conclusion, this is the first study focusing on the topical application of PRP in the treatment of open wounds in laboratory cats, and our results are encouraging—showing a more rapid healing in the PRP group.

Closure-related complications after median sternotomy in cats: 26 cases (2010-2020)

OBJECTIVES

The aim of this study was to determine closure-related complications and outcome after median sternotomy (MS) in cats.

METHODS

This was a retrospective, multicentric study. The medical records of cats undergoing MS from six referral hospitals were reviewed (2010-2020). Data retrieved included signalment, history, presenting complaints, surgery, patient outcomes and complications. Follow-up was performed via patient records and email/telephone contact with both owners and referring veterinarians. Descriptive statistics were performed.

RESULTS

Data on 36 cats were collected; four were excluded due to insufficient follow-up and six died less than 5 days after surgery. Twenty-six cats survived to discharge (survival rate 81%). Three cats had a full sternotomy (FS) performed and 23 cats a partial sternotomy (PS). Of the cats that underwent a PS, six included the manubrium (PSM) and three included the xyphoid process. For 14 cats, the length of sternotomy was unknown. Sternotomy closure was performed with suture in all cats. Two cats (7.7%) developed closure-related complications, both after PSM, during the long-term follow-up, one mild, slightly displaced sternal fracture and one severe, sternal dehiscence (without skin wound dehiscence) requiring revision surgery. No seroma, surgical site infection or wound dehiscence occurred. The most common reason for MS was the presence of a thoracic mass (17/26; 65%), with thymoma being the most common (11/17; 65%).

CONCLUSIONS AND RELEVANCE

MS has a low closure-related complication risk in cats when compared with dogs. Complications in cats present differently to what has been previously described in dogs.

Pelvic Endoprosthesis after Hemipelvectomy Using a 3D-Printed Osteotomy Guide for Infiltrative Osteoma in a Cat

With the development of 3D printing and surgical techniques, various defect reconstruction methods after tumor resection have been applied not only in humans but also in veterinary medicine. This report describes a case of reconstruction after hemipelvectomy for an osteoma in a cat using a 3D-printed pelvic endoprosthesis and micro total hip replacement (mTHR). A 5-year-old spayed female Turkish Angora cat was referred for a 1-month history of constipation and intermittent weight-bearing lameness in the left hindlimb. An osteoma in the pelvis measuring 4.5 × 3 × 5.4 cm was identified based on diagnostic examinations. A left mid-to-caudal partial and right caudal partial hemipelvectomy, and a left femoral head and neck osteotomy, were planned to remove the mass. Reconstruction of the bone defect using 3D-printed metal endoprosthesis and mTHR in the left hindlimb was intended. During right caudal partial hemipelvectomy, right femoral head and neck osteotomy was performed because there was infiltration in the medial wall of the acetabulum. Histopathological examination confirmed the diagnosis of an osteoma. Two weeks post-surgery, surgical debridement and femoral stem removal were performed because of delayed wound healing and sciatic neurapraxia, leading to femoral stem dislocation from the cup. The delayed wound healing and sciatic neurapraxia were appropriately addressed. The cat regained normal weight and defecation 4 weeks post-operatively. Two years post-surgery, the patient recovered with an almost normal gait. Hemipelvectomy with 3D-printed endoprosthesis provides a safe surgical option with favorable outcomes for neoplasms in the pelvis of cats.

Wound healing in animals: a review of physiology and clinical evaluation

Wound healing is a complicated process consisting of overlapping phases directed and regulated by many mediators of healing produced locally at the wound. The end goal of wound healing is the production of tissue at the site of injury which has a similar structure and provides protection to the body. Any alterations in the normal healing process can lead to delayed healing or additional tissue damage. Factors that contribute to aberrant wound healing can be species-specific and include both intrinsic (systemic) factors and extrinsic (environmental) factors. Management of wounds and recognition of alterations can be optimised by adoption of a structured framework for wound assessment, such as the TIME principle (acronym referring to the following categories: tissue, inflammation or infection, moisture, and edge of wound or epithelial advancement). This review article provides an overview of the phases of wound healing, variation of healing among different species, factors reported to delay healing, and an introduction to the TIME principle as a structured approach to clinical evaluation of wounds.

Filling the vacuum: Role of negative pressure wound therapy in open wound management in cats

PRACTICAL RELEVANCE

Open wounds and their treatment present a common challenge in veterinary practice. Approaching 15 years ago negative pressure wound therapy (NPWT) started to be incorporated into clinical veterinary medicine, and its availability is becoming more widespread in Europe and the USA. Use of this therapy has the potential to significantly increase the healing rate of open wounds as well as free skin grafts in small animals, and it has been occasionally described for the management of feline wounds.

AIM

This review describes the mechanisms of action of, and indications for, NPWT, and offers recommendations for NPWT specific to feline patients.

EVIDENCE BASE

The information presented is based on the current evidence and the author's clinical experience of the technique gained over the past 12 years. Comparative studies of different treatment options are lacking and, since wound healing in cats and dogs differs, cat-specific studies are especially needed. Well-designed wound healing studies comparing different advanced techniques will improve open wound healing in cats in the future, and potentially allow better understanding of the role of NPWT in this setting.

Outcomes and complications of anal sacculectomy for non-neoplastic anal sac disease in cats: 8 cases (2006-2019)

OBJECTIVES

To describe the features of non-neoplastic anal sac disease in cats, the surgical procedure, complications, surgical outcome and prognosis compared to well-established data for anal sacculectomy in canine patients.

MATERIALS AND METHODS

A retrospective review of medical records of cats undergoing anal sacculectomy for non-neoplastic disease between 2006 and 2019.

RESULTS

Eight cats were included in the study of which four of eight developed minor and self-limiting complications including defaecatory complications in three cases and superficial corneal ulceration in one case. No cat developed permanent faecal incontinence. No long-term postoperative complication was recorded. Median surgical time was 35 minutes (range, 20 to 42). Median hospitalisation time was 1.5 days (range, 1 to 4). The incidence of short-term minor complications is higher than previously reported in dogs, although this might be in agreement with a reported higher incidence in dogs smaller than 15 kg.

CLINICAL SIGNIFICANCE

Anal sacculectomy for non-neoplastic anal sac disease is a safe procedure in cats with relatively high rate of short-term but self-limiting, minor, postoperative complications.

Complete skin regeneration with medical honey after skin loss on the entire circumference of a leg in a cat

Second-intention healing of wounds on distal extremities in cats can be considered for superficial wounds involving less than 30% of the circumference of the limb. In our case the wound was characterized by complete loss of skin on 100% of the circumference of the limb from the elbow to the paw with contemporary ulnar fracture. Advanced reconstructive surgery or amputation of the leg was not acceptable for the owner; therefore, healing with medical honey was selected. In 49 days, an 80% reduction of the wound was observed. The wound healed completely by second intention with regrowth of hair and minimal scarring. Complete function was restored in the affected leg. To the authors' knowledge, this is the first written report of such extensive complete loss of skin on a leg in a cat healed by second intention with the use of medical honey.

Effect of subcutaneous closure technique on incisional complications and postoperative pain in cats undergoing midline celiotomy: A randomized, blinded, controlled trial

OBJECTIVE

To compare the effect of three methods of subcutaneous tissue closure on postoperative incisional complications and pain in cats.

STUDY DESIGN

Single-center, randomized, blinded, controlled trial conducted in a veterinary teaching hospital.

ANIMALS

Two hundred ninety-seven cats undergoing midline celiotomy for ovariohysterectomy (n = 280) or other abdominal procedure (n = 17).

METHODS

Cats (n = 297) were assigned to one of three subcutaneous closure methods: simple continuous apposition with tacking to the rectus fascia (n = 108, quilting [Q] group); simple continuous apposition (SC; n = 94); no subcutaneous closure (NC; n = 95). Primary outcomes were incidence of seroma formation, postoperative pain, and surgical site infection or dehiscence. Active follow-up was obtained at 10 and 30 days postoperatively.

RESULTS

Baseline characteristics did not differ between groups. Seroma was less common in the Q group (13.0%) than in the NC (27.3%) and SC (25.9%) groups (P = .03). Compared with the other two groups, the relative risk of seroma formation in the Q group was 0.49 (95% CI = 0.28-0.86, P = .01). Median mechanical pain thresholds were higher (indicating greater comfort) in cats with subcutaneous sutures (Q and SC = 1.23 [interquartile range (IQR), 0.2-2.6 N], NC = 0.83 [IQR, 0-1.87 N], P = .04) on the day after surgery.

CONCLUSION

Closing subcutaneous tissues with a quilting closure pattern reduced seroma formation in cats undergoing celiotomy.

CLINICAL SIGNIFICANCE

Placing a quilting suture pattern in the subcutaneous tissues after celiotomy is a simple low-cost measure that reduces seromas in cats. Abstaining from subcutaneous closure cannot be recommended because of increased seroma formation and pain.

Retrospective comparison of negative pressure wound therapy and silver-coated foam dressings in open-wound treatment in cats

Objectives The objective of this study was to evaluate negative pressure wound therapy (NPWT) for the treatment of complicated wounds in cats. Methods Twenty cats undergoing open-wound treatment in two clinics were classed according to treatment method: NPWT (group A, n = 10) and polyurethane foam dressing (group B, n = 10). Pairs of patients from each group were matched based on wound conformation, localisation and underlying cause. Cats from both groups were compared in terms of duration of previous treatment, time to closure and complications. Results Signalment, duration of previous treatment, antibiotic and antiseptic treatment, and bacterial status were comparable between groups. Total time to wound closure was significantly shorter ( P = 0.046, strong effect size; Cohen d = 0.8) in group A (25.8 days, range 11.0-57.0 days) compared with group B (39.5 days, range 28.0-75.0 days). NPWT-treated wounds suffered fewer complications and became septic less frequently during treatment compared with wounds treated with a foam dressing. The progression of fat tissue necrosis was particularly well controlled under NPWT, resulting in fewer deaths due to this condition in this group. However, although a strong effect of NPWT on the progression of infection, fever and sepsis was detected (Cramer-V 0.5), this difference was not significant. Conclusions and relevance This study demonstrated that time to healing was considerably shorter, and complication rate lower, in NPWT-treated animals compared with foam dressing-treated cats. In particular, the effective management of infection by NPWT emphasises the value of NPWT in the treatment of cats suffering from infected wounds.

The effect of color type on early wound healing in farmed mink (Neovison vison)

BACKGROUND

Individual differences of mink, including color type, are speculated to affect the course of wound healing, thereby impacting wound assessment and management on the farms, as well as the assessment of wounds in forensic cases. In this study, we examined the effect of color type on early wound healing in farmed mink. Full thickness excisional wounds (2 × 2 cm) were made on the back in 18 mink of the color types Brown, Silverblue and Blue Iris. Gross and microscopic pathology of the wounds was evaluated 2 days post-wounding together with degree of wound size reduction, presence of bacteria and blood analyses.

RESULTS

Pathological examination on day 2 showed the greatest mean wound size reduction in Brown mink (11.0%) followed by Blue Iris (7.9%) and Silverblue (1.6%). Bacteria were cultured from all wounds, and predominantly Staphylococcus species were recovered in mixed or pure culture. Histopathology from day 2 wounds showed a scab overlying necrotic wound edges, which were separated from underlying vital tissue by a demarcation zone rich in polymorphonuclear leukocytes. Fibroblasts and plump endothelial cells were more numerous in the deeper tissues. Complete blood count parameters were within normal ranges in most cases, however, the mink showed mildly to markedly decreased hematocrit and six mink of the color types Silverblue and Blue Iris showed moderately elevated numbers of circulating segmented neutrophils on day 2. There was a marked increase in concentration of serum amyloid A from day 0 to day 2 in all color types.

CONCLUSIONS

We have described differences in early wound healing between mink of the color types Brown, Silverblue and Blue Iris by use of an experimental wound model in farmed mink. The most pronounced difference pertained to the degree of wound size reduction which was greatest in Brown mink, followed by Blue Iris and Silverblue, respectively.

Outcome of full-thickness skin grafts used to close skin defects involving the distal aspects of the limbs in cats and dogs: 52 cases (2005-2012)

OBJECTIVE

To describe the outcome of full-thickness skin grafts used to close skin defects involving the distal aspects of the limbs in cats and dogs and identify factors associated with outcome.

DESIGN

Retrospective case series.

ANIMALS

20 cats and 32 dogs with a skin defect involving the distal aspect of a limb that received 58 full-thickness skin grafts between 2005 and 2012.

PROCEDURES

Data regarding patient signalment, location and cause of the skin defect, surgical and anesthetic duration, and postoperative bandaging protocol were obtained from the medical records. Graft outcome was assessed by interpreting descriptions in the records; skin viability over ≥ 75% of the graft area between 7 and 14 days after surgery was considered a successful outcome.

RESULTS

For 4 of the 58 grafts, graft outcome could not be determined from the medical record. For the remaining grafts, success rate was significantly higher for grafts placed in cats (17/22 [77%]) than in dogs (12/32 [38%]). The overall complication rate was 50%; complications included skin graft failure, donor site dehiscence, and bandage-induced sloughing of skin adjacent to the graft recipient site. In addition to species, anatomic location of the skin defect was identified as a prognostic indicator of graft outcome.

CONCLUSIONS AND CLINICAL RELEVANCE

Full-thickness skin grafting had a higher success rate in cats than in dogs. Skin grafts applied to the antebrachium, compared with other locations on the distal aspects of the limbs, were associated with a poorer prognosis.

Effects of two occlusive, hydrocolloid dressings on healing of full-thickness skin wounds in cats

OBJECTIVES

To determine the effects of two occlusive, hydrocolloid dressings on second intention wound healing in cats.

METHODS

Three 2×2 cm full-thickness skin wounds were created on each side of the trunk of 10 cats. Two bilateral wounds were bandaged using different hydrocolloid dressings, namely Hydrocoll and DuoDerm while a semi-occlusive pad (Melolin) was applied to the third bilateral wound (control group). Wound planimetry, subjective evaluation of wound healing, and qualitative bacterial cultures were performed on the right-sided wounds, whereas left-sided wounds were subjected to histological examination.

RESULTS

Subjective evaluation revealed accelerated (p <0.01) granulation tissue formation in hydrocolloid-treated wounds. The amount of wound exudate was initially greater (p <0.01) in these wounds. Seventeen out of 120 evaluated wounds (14.2%) produced purulent exudate, 11 of which showed Staphylococcus aureus growth. Fewer control wounds (3/17) emitted purulent exudate, but all of them yielded moderate bacterial growth as compared to hydrocolloid-treated wounds (8/17) which had a low incidence of bacterial growth. The only significant difference in histological variables was increased cellular infiltration noted on day 7 in Hydrocoll-treated wounds compared to controls. No significant differences in planimetry variables were found between groups.

CLINICAL SIGNIFICANCE

Despite the initially increased amount of wound exudate and the low growth of Staphylococcus aureus, hydrocolloid dressings accelerate granulation tissue formation and can hence be suggested for second intention wound healing in cats.

A preliminary study of the effect of closed incision management with negative pressure wound therapy over high-risk incisions

Background

Certain postoperative wounds are recognised to be associated with more complications than others and may be termed high-risk. Wound healing can be particularly challenging following high-energy trauma where wound necrosis and infection rates are high. Surgical incision for joint arthrodesis can also be considered high-risk as it requires extensive and invasive surgery and postoperative distal limb swelling and wound dehiscence are common. Recent human literature has investigated the use of negative pressure wound therapy (NPWT) over high-risk closed surgical incisions and beneficial effects have been noted including decreased drainage, decreased dehiscence and decreased infection rates. In a randomised, controlled study twenty cases undergoing distal limb high-energy fracture stabilisation or arthrodesis were randomised to NPWT or control groups. All cases had a modified Robert-Jones dressing applied for 72 h postoperatively and NPWT was applied for 24 h in the NPWT group. Morphometric assessment of limb circumference was performed at six sites preoperatively, 24 and 72 h postoperatively. Wound discharge was assessed at 24 and 72 h. Postoperative analgesia protocol was standardised and a Glasgow Composite Measure Pain Score (GCPS) carried out at 24, 48 and 72 h. Complications were noted and differences between groups were assessed.

Results

Percentage change in limb circumference between preoperative and 24 and 72 h postoperative measurements was significantly less at all sites for the NPWT group with exception of the joint proximal to the surgical site and the centre of the operated bone at 72 h. Median discharge score was lower in the NPWT group than the control group at 24 h. No significant differences in GCPS or complication rates were noted.

Conclusions

Digital swelling and wound discharge were reduced when NPWT was employed for closed incision management. Larger studies are required to evaluate whether this will result in reduced discomfort and complication rates postoperatively.

Wound Care

Wound care requires an understanding of normal wound healing, causes of delays of wound healing, and the management of wounds. Every wound must be treated as an individual with regard to cause, chronicity, location, and level of microbial contamination, as well as patient factors that affect wound healing. Knowledge of wound care products available and when negative pressure wound therapy and drain placement is appropriate can improve outcomes with wound healing. Inappropriate product use can cause delays in healing. As a wound healing progresses, management of a wound and the bandage material used must evolve.

Effect of locally injected autologous platelet-rich plasma on second intention wound healing of acute full-thickness skin defects in dogs

OBJECTIVES

Second intention wound healing may be impaired by wound and host factors and thus more advanced therapies are required for a fast and satisfactory outcome. Platelet-rich plasma (PRP), rich in growth factors and cytokines essential for tissue repair, could improve wound healing. The purpose of this experimental study was to evaluate the effect of locally injected autologous PRP on second intention healing of acute full-thickness skin defects in dogs.

METHODS

Three 2 x 2 cm full-thickness skin defects were created bilaterally on the dorsolateral area of the trunk of six Beagle dogs. The wounds of one randomly selected side received PRP treatment, whereas the contralateral wounds were left untreated (controls). Wound healing was evaluated by planimetry, laser-Doppler flowmetry measurements of tissue perfusion, and histologically.

RESULTS

The rate of wound healing did not differ significantly between the two groups. Tissue perfusion was significantly higher in the PRP-treated group (p = 0.008) compared to controls on day 10. Histological evaluation revealed a trend towards greater collagen production and a significantly better collagen orientation (p = 0.019) in PRP-treated wounds on day 20.

CLINICAL SIGNIFICANCE

Locally injected autologous PRP does not accelerate the healing process, but increases tissue perfusion and may promote the formation of organized collagen bundles in acute full-thickness skin defects in dogs.

Comparative wound healing--are the small animal veterinarian's clinical patients an improved translational model for human wound healing research?

Despite intensive research efforts into understanding the pathophysiology of both chronic wounds and scar formation, and the development of wound care strategies to target both healing extremes, problematic wounds in human health care remain a formidable challenge. Although valuable fundamental information regarding the pathophysiology of problematic wounds can be gained from in vitro investigations and in vivo studies performed in laboratory animal models, the lack of concordance with human pathophysiology has been cited as a major impediment to translational research in human wound care. Therefore, the identification of superior clinical models for both chronic wounds and scarring disorders should be a high priority for scientists who work in the field of human wound healing research. To be successful, translational wound healing research should function as an intellectual ecosystem in which information flows from basic science researchers using in vitro and in vivo models to clinicians and back again from the clinical investigators to the basic scientists. Integral to the efficiency of this process is the incorporation of models which can accurately predict clinical success. The aim of this review is to describe the potential advantages and limitations of using clinical companion animals (primarily dogs and cats) as translational models for cutaneous wound healing research by describing comparative aspects of wound healing in these species, common acute and chronic cutaneous wounds in clinical canine and feline patients, and the infrastructure that currently exists in veterinary medicine which may facilitate translational studies and simultaneously benefit both veterinary and human wound care patients.

Omentalisation of the head in cats: a cadaver study

The involvement of the greater omentum in reconstructive, abdominal and thoracic surgery is based on its manifold qualities, which include immunological support, lymphatic drainage, angiogenesis, adhesion, haemostasis and fat storage. The purpose of this study was to determine whether the greater omentum could be extended to the head. In addition, we evaluated the surgical procedures necessary for this extension. Our study reveals that specific surgical lengthening techniques of the greater omentum, such as dorsal extension and inverted L-shape elongation, are necessary to successfully transpose the omentum to the head in cats. As the survival of the omentum after transposition procedures is still unknown, its application in chronic non-healing wounds of the head in cats warrants further investigation.

Considerations for laboratory animal imaging center design and setup

In vivo animal imaging is an outstanding noninvasive tool to study the pathophysiology of disease or response to therapy; additionally, serial imaging reduces the required number of experimental animals. Because of the tremendous capital investment, we recommend the imaging center be a shared resource to facilitate innovative and productive cross-disciplinary scientific collaborations. A shared center also enables a broader range of imaging, as equipment is often cost prohibitive for smaller facilities. A multitude of factors will determine the architectural design, facility efficiency, and functionality. Important considerations to determine during the planning stages include the types of animals to be imaged, types of imaging studies to be performed, types of imaging equipment and related services to be offered, and the location of the imaging center. Architects must work closely with manufacturers to accommodate equipment-related building specifications; facility planners and veterinarians can provide a practical logistical design that will ensure efficient functionality. Miscellaneous considerations include biosecurity levels, use of radioisotopes, and personnel safety in the imaging environment. The ideal imaging center will include space to house animals and perform necessary preimaging procedures, state-of-the-art in vivo imaging devices and the most up-to-date anesthesia, physiological support, and monitoring equipment. The center staff should include imaging specialists for technical development and data analysis. As it is difficult to provide a comprehensive manual for setting up an in vivo animal imaging center, we offer advice based on our experiences with the National Institutes of Health Mouse Imaging Facility. Because magnetic resonance imaging (MRI) is the most expensive imaging tool, requires specific building design considerations, and poses unique occupational health and safety risks, we focus on MRI as the foundation for an imaging facility design.

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.

Differences in cutaneous wound healing between dogs and cats

Regardless of the species involved, wound healing follows a predictable course of overlapping phases. In spite of these commonalities, significant species differences in cutaneous wound healing have been uncovered in the Equidae and, more recently, between the dog and cat. It has also recently been shown that the subcutaneous tissues play an important supporting role in cutaneous wound healing, which may help to ex-plain healing differences between cats and dogs. These discoveries may improve veterinarians' understanding of problem wound healing in the cat and, hopefully, lead to better strategies for wound management in this sometimes troublesome species.

Management of Specific Skin Wounds

This article deals with the range of skin conditions found in the dog and the cat, including intertriginous diseases, dermal sinuses, chronic lesions involving the limbs, and specific wound infections for which surgical intervention may play a useful role in their successful management.