title: Heparin versus tirofiban in microvascular anastomosis: randomized controlled trial in a rat model.
abstract: OBJECTIVE
  Free flaps have become the mainstay of reconstruction after resection of head and neck cancer. Thrombosis after microvascular reanastamosis is a common reason for free flap failure. Various anticoagulants have been used topically and systemically to prevent thrombosis. Tirofiban is a glycoprotein IIb/IIIa inhibitor that prevents platelet aggregation and helps prevent thrombosis. The purpose of this study was to compare the thrombosis rate of topical heparin to topical heparin + tirofiban in a thrombogenic free flap model in rats.
  
  
  METHODS
  Prospective, randomized, double-blind, controlled trial.
  
  
  METHODS
  A thrombogenic free flap model was developed by raising a fasciocutaneous flap based on the epigastric artery in the Sprague-Dawley rat. An intimal flap was created proximal to the anastomosis site to increase thrombosis rates. Eighty rats were randomized to this thrombogenic free flap model using topical saline, heparin, or topical heparin + tirofiban. Each free flap was assessed for skin necrosis, capillary refill, and vessel thrombosis at 48 hours postprocedure. Data for each group were collected in a double-blind fashion.
  
  
  RESULTS
  The heparin + tirofiban group had a 23% lower thrombosis rate and hence free flap failure rate when compared to the heparin alone group (p  =  .044).
  
  
  CONCLUSIONS
  The use of topical tirofiban in addition to topical heparin in microvascular surgery results in reduced rates of thrombosis and should be considered for use in head and neck oncology patients undergoing free flap reconstruction.
authors: Division of Otolaryngology-Head and Neck Surgery, University of Alberta, Edmonton, AB.
authors: Prabhjyot
authors: P
authors: Singh
authors: Lin
authors: L
authors: Fu Zhu
authors: Peter
authors: P
authors: Dziegielewski
authors: Jeffrey
authors: J
authors: Harris
authors: Hadi
authors: H
authors: Seikaly
mesh_terms: D000714:Anastomosis, Surgical / Q000379:methods; D000818:Animals; D004195:Disease Models, Animal; D004359:Drug Therapy, Combination; D005205:Fascia / Q000098:blood supply / Q000637:transplantation*; D005343:Fibrinolytic Agents / Q000008:administration & dosage; D005500:Follow-Up Studies; D058752:Free Tissue Flaps / Q000098:blood supply*; D006258:Head and Neck Neoplasms / Q000601:surgery; D006493:Heparin / Q000008:administration & dosage*; D008866:Microsurgery / Q000379:methods*; D009374:Neoplasms, Experimental; D010974:Platelet Aggregation / Q000187:drug effects; D019039:Platelet Glycoprotein GPIIb-IIIa Complex / Q000037:antagonists & inhibitors; D011446:Prospective Studies; D051381:Rats; D017207:Rats, Sprague-Dawley; D019651:Plastic Surgery Procedures / Q000379:methods; D016038:Skin Transplantation / Q000379:methods*; D007507:Therapeutic Irrigation; D013927:Thrombosis / Q000517:prevention & control*; D000077466:Tirofiban; D016896:Treatment Outcome; D014443:Tyrosine / Q000008:administration & dosage / Q000031:analogs & derivatives*; D014945:Wound Healing / Q000187:drug effects
chemical_list: D005343:Fibrinolytic Agents; D019039:Platelet Glycoprotein GPIIb-IIIa Complex; D014443:Tyrosine; D006493:Heparin; D000077466:Tirofiban