title: The effects of epidermal debridement of partial-thickness burns on infection and reepithelialization in swine.
abstract: OBJECTIVE
  Early postburn debridement of burn blisters is controversial. This study was conducted to compare rates of infection and reepithelialization in debrided vs nondebrided second-degree burns in swine.
  
  
  METHODS
  This was a prospective, blinded, controlled, experimental trial using isoflurane-anesthetized swine. Standardized partial-thickness burns were inflicted by applying an aluminum bar preheated to 80 degrees C to the backs and flanks of two young pigs for 20 seconds. In half of the burns the necrotic epidermis was manually debrided. All burns were randomly treated with octylcyanoacrylate spray (OCA) or dry gauze (C). Full-thickness biopsies were taken at 7, 10, and 14 days for blinded histopathologic evaluation. The primary outcomes were the proportions of infected burns at days 7 and 10 and the proportion of completely reepithelialized burns at day 14. Burns were considered infected in the presence of intradermal neutrophils containing bacteria (intraobserver agreement, K = 1.00). A secondary outcome was the proportion of burns with the presence of scar tissue (abnormal collagen under polarized light; intraobserver correlation, K = 0.93). Chi-square tests were used for group comparisons. This study had 90% power to detect a 40-percentage-point difference in infection rates (alpha = 0.05).
  
  
  RESULTS
  A total of 126 biopsies from 42 burns were available for review. Infection rates were higher in the debrided burns both at day 7 (55% vs 4.5%, p < 0.001) and at day 10 (65% vs 9%, p < 0.001) after injury. The proportion of nondebrided burns that were completely reepithelialized was higher at days 10 (68% vs 0%, p < 0.001) and 14 (100% vs 65%, p = 0.003). The presence of scar tissue was more common in debrided burns (75% vs 4.5%, p < 0.001). Burns treated with OCA had fewer infections than controls (4% vs 55%, p < 0.001). Fewer OCA-treated debrided burns were reepithelialized at 14 days than those that were not debrided (30% vs 100%, p = 0.001).
  
  
  CONCLUSIONS
  Under the current study conditions, early postburn epidermal debridement of second-degree burns resulted in more infections and slower reepithelialization rates in swine. The effects of early postburn epidermal debridement in humans should be explored.
authors.affiliation: Department of Emergency Medicine, State University of New York at Stony Brook, USA. asinger@epo.som.sunysb.edu
authors.forename: A J
authors.initials: AJ
authors.lastname: Singer
authors.forename: H C
authors.initials: HC
authors.lastname: Thode
authors.forename: S A
authors.initials: SA
authors.lastname: McClain
mesh_terms: D000818:Animals; D002056:Burns / Q000503:physiopathology / Q000628:therapy*; D003487:Cyanoacrylates / Q000008:administration & dosage; D003646:Debridement / Q000009:adverse effects*; D004817:Epidermis / Q000502:physiology / Q000601:surgery*; D004848:Epithelium / Q000502:physiology; D005260:Female; D012038:Regeneration; D013552:Swine; D014014:Tissue Adhesives; D014946:Wound Infection / Q000209:etiology*
chemical_list: D003487:Cyanoacrylates; D014014:Tissue Adhesives; C119247:octylcyanoacrylate