Reepithelialization of mid-dermal
burns is delayed by the presence of a layer of necrotic eschar. The authors hypothesized that rapid selective
debridement using an enzymatic
bromelain-based preparation, Debrase®, would speed reepithelialization. Forty mid-dermal
burns (2.5 × 2.5 cm) were created on the back and flanks of two anesthetized domestic pigs (25 kg) using an
aluminum bar (150 g) preheated in hot water (80°C) and applied for 20 seconds. The
burns were randomized to a 4-hour topical application of Debrase® (n = 20) or its vehicle (n = 20) followed by daily application of a
petrolatum-based triple
antibiotic.
Wounds were visualized and photographed daily for evidence of reepithelialization. Reepithelialization was considered complete when the entire
wound was opaque and dry when blotted with tissue paper. 4-mm full-thickness biopsies were obtained for histological analysis using
hematoxylin and
eosin staining by a board-certified dermatopathologist masked to the
burn therapy at 7, 9, 11, and 13 days after injury. The primary outcome was time to complete reepithelialization of the
burns. Secondary outcomes were the percentage of
burns that were reepithelialized at days 7, 11, and 13 and the mean percentage reepithelialization on microscopic analysis. A sample of 20
burns in each group had 80% power to detect a 2-day difference in the time to complete reepithelialization (two-tailed, P < .05). Application of Debrase®, but not the control vehicle, resulted in dissolution of the necrotic upper dermis in all treated
burns. The mean time to complete reepithelialization was faster for Debrase®-treated (7.4 ± 0.8 days) than control-treated (9.1 ± 2.1 days)
burns: difference, 1.7 days (95% confidence interval, 0.5-2.9). The percentage of completely reepithelialized Debrase®- and control-treated
burns were day 7, 65.0 vs 25.0% (P = .02); day 9, 80.0 vs 40.0% (P = .02); and day 11, 100.0 vs 92.0% (P = .45). Treatment of mid-dermal porcine
burns with a single topical application of Debrase® results in earlier
wound reepithelialization.