Background: proteolytic enzymes such as collagenase, fibrinolysin and deoxyribonuclease are used for debriding purulent or fibrinous pressure ulcers.
Objective: to test the hypothesis that collagenase debrides necrotic pressure ulcers more effectively than fibrinolysin/deoxyribonuclease.
Methods: we enrolled 135 elderly patients with pressure ulcers in a randomized, prospective double-blind trial. Patients were treated until complete wound debridement or for a maximum of 4 weeks with twice-daily applications of collagenase or fibrinolysin/deoxyribonuclease. The primary endpoint was percentage change in the yellow or black wound surface. Secondary endpoints were wound environment, margins, depth, pocketing, area and healing. Assessment was by two independent dermatologists who were unaware of the treatment administered and evaluated results from photographs taken at the beginning and end of treatment.
Results: on intention-to-treat analysis, collagenase gave slightly better results with regard to the primary endpoint in the 121 assessable patients, but this difference was not statistically significant (P=0.115). Additional efficacy measures did not show any statistically significant difference between the groups.
Conclusion: there was no evidence of a difference between collagenase and fibrinolysin/deoxyribonuclease in the debridement of pressure ulcers.