A Staged Approach to Healing Complex Wounds Using Cellular, Acellular, and Matrix-Like Products

Introduction: Healing wounds with exposed structures and poorly vascularized, or necrotic tissue is an immense challenge. Dermal matrices are an effective way to “downstage” such wounds by facilitating the growth of a “neo-dermis” while protecting from infection and moisture loss, preparing the wound bed for subsequent matrix applications or skin grafting.[1] When skin grafting still remains questionable due to wound characteristics or patient comorbidities, living cellular matrices(LCM*) may provide a more viable option to autologous grafting.[2] We assessed the efficacy of a multistage approach starting with a biodegradable temporizing matrix(BTM*), folllowed by a secondary, and at times, tertiary matrix to further promote regeneration, and eventually, a LCM*, in comorbid patients with highly complex wounds.Methods:Patients underwent OR wound debridement and BTM* application, followed by placement of a nonadhesive dressing and secondary dressing. All followed weekly at our clinic for wound assessments and dressing changes. At 21 days, patients returned to the OR for removal of the outer BTM* covering, debridement, and additional matrix application. Once engraftment was noted, patients either underwent a STSG or serial LCM* applications. Subjective pain, drainage, and wound area reduction was assessed weekly.Results:One patient with calciphylaxis and a left leg wound(130cm2) underwent debridement and BTM* application followed by application of a synthetic, electrospun polymer matrix(EPM*). At one month, her wound showed complete EPM* engraftment and she noted less pain. After 3 LCM* applications, her wound closed. She later developed a wound on her right leg(150cm2) and underwent the same procedure, closing after 11 LCM* applications.A second patient with critical limb ischemia status-post revascularization had dry gangrene of his right foot, with areas of necrotic muscle and tendon(240cm2). After BTM* followed by EMP* applications, his dorsal foot showed healthy granulation tissue, though his lateral foot tendons and ligaments were still visible and necrotic. He underwent STSG to the dorsal foot and acellular fish skin(AFS*) application laterally. After 1 week, improved granulation was noted laterally and he began serial LCM* applications.Discussion: BTM* facilitates good granulation in a hostile environment and can manage drainage and decrease pain. A synthetic dermal substitute is a good second strategy to promote further granulation after BTM* in complex wounds. While EPM* has been effective, we have seen a better response with dermal regeneration templates, so EPM* may not be our first choice with all options available. Patients contraindicated to complete STSG coverage may benefit more from LCM* over a single autologous graft. References:1.Chen AC, Lin TW, Chang KC, Chang DH. Strategic Use of Biodegradable Temporizing Matrix (BTM) in Wound Healing: A Case Series in Asian Patients. J Funct Biomater. May 18 2024;15(5) 2. Eudy M, Eudy CL, Roy S. Apligraf as an Alternative to Skin Grafting in the Pediatric Population. Cureus. Jul 2021;13(7):e16226