title: Viability of randomized skin flaps-an experimental study in rats.
abstract: Randomized skin flaps are extensively used in plastic surgery, but the possibility of necrosis has challenged their use. Several studies have been conducted aiming to find ways to reduce the occurrence of necrosis. We evaluated the effects of pentoxifylline (PTX) and hyaluronidase (HLD), each alone or combined, on randomized rat skin flaps.
  
  
  
  Fifty male Wistar rats were divided into five groups of 10 animals each: control I, control II, PTX, HLD, PTX-HLD. Substances were administered from the first to the 14th postoperative day. The necrotic area was measured on the seventh and 14th postoperative day; the animals were killed on the 14th day, when samples were collected for histologic and immunohistochemical examination.
  
  
  
  On the seventh day, percentage of the necrotic area was significantly reduced in PTX, HLD, and PTX-HLD animals compared with control groups. On 14th day, percentage of the necrotic area in PTX, HDL, and PTX-HLD groups was also significantly reduced compared with control groups. PTX and PTX-HLD showed a significant reduction in dermis cellularity, VVof macrophages, and myofibroblasts compared with control groups; PTX showed a significant enhancement of LVof blood vessels compared with all other groups.
  
  
  
  The use of each substance alone or combined increased flap viability compared with control groups. On the seventh day, PTX exhibited lower viability than HLD, whereas on the 14th day there was no difference between treated groups. PTX alone enhanced the LVof blood vessels, whereas PTX-HLD did not. However, PTX-HLD was more effective in decreasing the dermis cellularity and macrophage VVthan HLD alone.
authors.affiliation: Post-Graduation Program in Physiopathology and Surgical Sciences, Department of General Surgery, Rio de Janeiro State University, Rio de Janeiro, Brazil. Electronic address: nsingiantnio@yahoo.com.br.
authors.forename: Nsingi N
authors.initials: NN
authors.lastname: António
authors.affiliation: Laboratory of Tissue Repair, Institute of Biology Roberto Alcantara Gomes, Rio de Janeiro State University, Rio de Janeiro, Brazil.
authors.forename: Andréa
authors.initials: A
authors.lastname: Monte Alto Costa
authors.affiliation: Laboratory of Experimental Surgery, Department of General Surgery, Rio de Janeiro State University, Rio de Janeiro, Brazil.
authors.forename: Ruy G
authors.initials: RG
authors.lastname: Marques
mesh_terms: D000818:Animals; D004334:Drug Administration Schedule; D004359:Drug Therapy, Combination; D006085:Graft Survival / Q000187:drug effects*; D006821:Hyaluronoglucosaminidase / Q000494:pharmacology / Q000627:therapeutic use*; D015552:Injections, Intralesional; D008297:Male; D009336:Necrosis / Q000517:prevention & control; D010431:Pentoxifylline / Q000494:pharmacology / Q000627:therapeutic use*; D010726:Phosphodiesterase Inhibitors / Q000494:pharmacology / Q000627:therapeutic use*; D011183:Postoperative Complications / Q000517:prevention & control*; D020011:Protective Agents / Q000494:pharmacology / Q000627:therapeutic use; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D012867:Skin / Q000187:drug effects / Q000473:pathology*; D013524:Surgical Flaps / Q000473:pathology*; D016896:Treatment Outcome
chemical_list: D010726:Phosphodiesterase Inhibitors; D020011:Protective Agents; D006821:Hyaluronoglucosaminidase; D010431:Pentoxifylline
keywords: Hyaluronidase; Necrosis; Pentoxifylline; Randomized skin flap; Viability