Evaluation of Six Split-thickness Skin Graft Donor-site Dressing Materials in a Swine Model

Split-thickness skin grafting is a widely used reconstructive technique for the replacement of damaged or missing skin caused by burns, trauma, surgical resection for cancer, and chronic wounds.1 Split-thickness autografts are harvested by excising the epidermis and part of the dermis, leaving a donor-site wound that can vary in thickness.1 Donor-site wounds generally heal by reepithelialization in 7–14 days, after which they may be used repeatedly when a large defect necessitating repair exists, such as an extensive burn.2–5 Therefore, proper wound care of the donor site is critical to reduce time to complete reepithelialization and to prevent significant morbidity resulting from delayed healing, infection, or conversion of the donor site to a full-thickness wound.6–9 Optimal donor-site dressings promote wound healing by preventing dessication, removing excess exudate, allowing gaseous exchange, and accelerating reepithelialization while being comfortable for the patient, resistant to infection, easily applied, and cost-effective.7–14 Although petrolatum fine-mesh gauze impregnated with the antiseptic bismuth tribromophenate (Xeroform) is the preferred dressing at our institution and in some burn centers around the world,15 we question whether a more effective dressing is available. Review of the literature has shown that impregnated fine-mesh gauze, calcium alginate, and polyurethane film are among the most commonly used dressings; however, newer materials such as hydrofibers, hydrocolloids, and foams are becoming more popular for use on split-thickness donor sites.3,8,15,16 Results of national and worldwide surveys indicate that practitioners often use the dressing they are most familiar with, regardless of performance.3,15,16 This is due, in part, to an overabundance of choices and a lack of consistent clinical evidence to support alternative materials.3,12,15,16 To date, 4 systematic reviews on the most effective donor-site dressings have been completed.7,10,17,18 These reviews were based mainly on small trials comparing a limited number of dressing types. Aggregate clinical evidence suggests that hydrocolloids and films may be superior to other materials, to include Xeroform; however, the authors agree that more conclusive evidence is needed.7,10,17,18 The largest randomized clinical trial evaluating 6 commonly used dressings was published in 2013 by the Recognizing Effective Materials By Randomizing and Assessing New Donorsite Treatments (REMBRANDT) study group.8 The authors reported that the use of hydrocolloid dressings resulted in the fastest healing of donor-site wounds, while gauze dressings were accompanied by a higher infection rate.8 Importantly, this randomized trial did not evaluate Xeroform.8 Although human studies are the most accurate way to determine the clinical effectiveness of donor-site dressings, it is often difficult to obtain sufficient numbers of similar wounds for randomized trials, thus limiting the number of materials compared. In addition, objective measurements of wound healing are restricted due to the need for biopsies obtained for histologic analysis. Animal models are thus a viable alternative to provide additional evidence to support the use of various dressings, with the pig being the most suitable animal model available because porcine skin is similar to that of humans in epidermal thickness, composition, vascularization, and healing.19 In this study, we used a swine model to determine which of 5 commonly used dressing materials, including polyurethane film (Opsite), calcium alginate (Kaltostat), hydrofiber (Aquacel), hydrocolloid (DuoDERM), and silicone-faced polyurethane foam (Mepilex), promotes wound healing most effectively for use on split-thickness skin graft donor sites when compared with our standard dressing, Xeroform. Parameters examined included reepithelialization, inflammation, prevention of infection, ease of use (application and wound care), and cost.