WOUND-HEALING - SPECIAL CONSIDERATIONS IN THE BURN PATIENT

Retention of the remnants of burned skin (eschar) and the formation of necrotic debris resulting from wound drainage and secretions (pseudoeschar) in burn wounds frequently interfere with the wound healing process. In addition, devitalized tissue and secretions at the wound surface are a nidus for infection. Native proteolytic enzymes in tissues or proteases produced by colonizing bacteria promote the separation of eschar and debris from the wound surface. However, since this process is lengthy, aggressive wound care is utilized to debride adherent and loose debris until the decision is made to either excise and graft the wound or await epithelialization. While native proteolytic enzymes or those produced by colonizing bacteria eventually affect eschar separation, the use of exogenous enzymes for wound debridement may accelerate wound cleaning and healing. Collagenase ointment, containing a collagenase derived from the fermentation of Clostridium histolyticum, possesses the unique ability to digest native and denatured collagen in necrotic tissue and has achieved wide-spread acceptance for the treatment of dermal ulcers. Since collagen accounts for 75% of the dry weight of skin tissue, the ability of collagenase to digest collagen at physiological pH and temperature ranges makes it a potentially important debriding agent for burn wounds. In a prospective, randomized, multicenter trial of 79 patients with partial-thickness burns, the efficacy of collagenase ointment for debriding wounds was compared to standard topical therapy. Endpoints were days to clean wound (absence of retained debris) and days to epithelialization. When paired treatment sites were compared within each patient, proportionately more of the collagenase-treated sites cleaned and healed before similar burn sites treated with silver sulfadiazine. The results of this multicenter study suggest that the use of collagenase for treatment of partial thickness burn wounds is efficacious and minimizes discomfort for the patient.