title: Effects of pentoxyfilline and heparin on reperfusion injury island skin flaps in rats exposed to tobacco.
abstract: BACKGROUND
  Ischemia-reperfusion injury is believed to be a major cause of transferred skin flap failure. Cigarette smoking is known to be associated with endogenous antioxidant depletion, hypercoagulability, and cutaneous vasoconstriction. This investigation was carried out to study possible effects of pentoxyfilline or heparin on rat skin reperfusion injury under tobacco exposure.
  
  
  METHODS
  Thirty-six rats were randomized into two major groups: 18 were exposed to cigarette smoke during a 4 wk period prior to surgery; the remaining 18 underwent a sham smoking procedure. Each group was further divided into three equal subgroups: heparin, pentoxyfilline, and saline solution. One identical skin flap was raised in each animal. The vasculature of the flap was clamped for 3 h and reperfused for 5 min. A venous blood sample was obtained from the flap after reperfusion for serum malondialdehyde (MDA) and myeloperoxidase (MPO) analysis. Flap survival was assessed 7 d after the procedure.
  
  
  RESULTS
  The lipid peroxidation levels and flap necrosis were significantly higher in the cigarette-smoking group skin flaps. There was also a decrease of MPO activity in this group compared with the non-smoking group. Heparin-treated rats had significantly lower MDA levels and showed the most viable percent area among smoking rats.
  
  
  CONCLUSIONS
  These data suggest that heparin had a significant beneficial effect both on flap survival and on the lipid peroxidation reduction after smoke exposure in the rat axial-pattern skin flap subjected to ischemia and reperfusion injury. Pharmacologic therapy may represent an alternative way to counteract tobacco effects in flap surgery in emergency situations.
authors.affiliation: Department of Surgery and Anatomy, Division of Plastic Surgery, Faculty of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil. fredericoalonso@netsite.com.br
authors.forename: Frederico A S
authors.initials: FA
authors.lastname: Freitas
authors.forename: Carlos E
authors.initials: CE
authors.lastname: Piccinato
authors.forename: Jesualdo
authors.initials: J
authors.lastname: Cherri
authors.forename: Werther G
authors.initials: WG
authors.lastname: Marchesan
mesh_terms: D000818:Animals; D000925:Anticoagulants / Q000494:pharmacology; D062109:Dermatologic Surgical Procedures; D004359:Drug Therapy, Combination; D016166:Free Radical Scavengers / Q000494:pharmacology; D006493:Heparin / Q000494:pharmacology*; D008297:Male; D008315:Malondialdehyde / Q000097:blood; D009336:Necrosis; D018384:Oxidative Stress / Q000187:drug effects; D010431:Pentoxifylline / Q000494:pharmacology*; D009195:Peroxidase / Q000097:blood; D051381:Rats; D017208:Rats, Wistar; D015427:Reperfusion Injury / Q000188:drug therapy*; D012867:Skin / Q000098:blood supply / Q000187:drug effects*; D013524:Surgical Flaps / Q000098:blood supply / Q000473:pathology*; D014028:Tobacco Smoke Pollution / Q000009:adverse effects*; D014661:Vasoconstriction / Q000187:drug effects / Q000502:physiology
chemical_list: D000925:Anticoagulants; D016166:Free Radical Scavengers; D014028:Tobacco Smoke Pollution; D008315:Malondialdehyde; D006493:Heparin; D009195:Peroxidase; D010431:Pentoxifylline