Closure of abdominal wall defects using acellular dermal matrix

Background: After some abdominal surgical procedures, the abdominal wall defect may be too large for closure by tension-free approximation of the wound margins because of tissue loss or swelling of the abdominal viscera. A variety of absorbable and nonabsorbable prosthetic materials have been used for emergency abdominal wall reconstruction. Of these materials, polytetrafluoroethylene (PTFE) sheets have proved to be the most efficacious. Methods: This study compared the efficacy of allogenic acellular dermal matrix (ADM) and PTFE as prosthetic materials for wound closure in rats with surgical, full-thickness, 2 x 3-cm abdominal wounds. Healing was studied among animals with and those without experimentally induced peritonitis for 21 days after surgery. Results: Acellular dermal matrix became vascularized and incorporated into the wound bed and was partially or fully epithelialized without the need for skin grafting. As a result, little superficial bleeding was seen, and ADM effectively closed the wounds even in the presence of peritonitis. Wounds treated with ADM also showed a significant reduction in wound area (sterile: p < 0.001; contaminated: p < 0.05). In contrast, PTFE temporarily closed the wounds, but was not incorporated into them. It consequently evoked the formation of extensive underlying granulation tissue that showed significant superficial bleeding when the PTFE was removed. Very limited wound contraction occurred in PTFE-treated wounds, and some instances of evisceration and fistula formation were observed. Wounds treated with both types of material showed significant amounts of adhesion to visceral organs underlying the wound site. Conclusions: Acellular dermal matrix exhibits a number of favorable features relative to PTFE for closing sterile or contaminated full-thickness abdominal wall defects.