title: Protective effects of activated protein C (APC) on free groin flaps after secondary venous stasis in the rat model.
abstract: BACKGROUND
  The goal of this study was to determine whether the focused delivery of APC by rinsing of free adipocutaneous groin flaps shows protective effects on flap survival following a fatal secondary venous stasis in a rat model.
  
  
  METHODS
  36 Sprague Dawley rats were randomized to three groups and free microvascular groin flaps were transplanted to the neck in each animal. 20 hours postoperatively the flap pedicle was re-explored and the distal stump of the flap artery was catheterised. Animals in group I (n = 12) remained untreated, whereas animals of group II were treated with 1 ml of Ringer's solution. Those in group III received 1 ml of APC (2 mg/kg). Afterwards the flap vein was clamped for 35 minutes. The skin of the flaps and the native contralateral groin was examined by intravital video microscopy using FITC-Dextran and CFDA-SE-labelled thrombocytes.
  
  
  RESULTS
  APC-pretreatment significantly increased the functional capillary density (FCD) of the flaps. Flap viability was 8% in group I (n = 1/12), 9% in group II (n = 1/11) and 60% in group III (n = 6/10), respectively. No partial flap loss was detected.
  
  
  CONCLUSIONS
  The focused delivery of APC resulted in significantly improved flap salvage.
authors.affiliation: Hand Surgery, Plastic Surgery and Aesthetic Surgery, University Hospital of the Ludwig-Maximilians-University, Munich, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Wallmichrath
authors.affiliation: Hand Surgery, Plastic Surgery and Aesthetic Surgery, University Hospital of the Ludwig-Maximilians-University, Munich, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Knab
authors.affiliation: Consultant for Lymphology of the Surgical Clinic Munich Bogenhausen, Munich, Germany.
authors.forename: R G H
authors.initials: RG
authors.lastname: Baumeister
authors.affiliation: Hand Surgery, Plastic Surgery and Aesthetic Surgery, University Hospital of the Ludwig-Maximilians-University, Munich, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Holzbach
authors.affiliation: Hand Surgery, Plastic Surgery and Aesthetic Surgery, University Hospital of the Ludwig-Maximilians-University, Munich, Germany.
authors.forename: R E
authors.initials: RE
authors.lastname: Giunta
authors.affiliation: Hand Surgery, Plastic Surgery and Aesthetic Surgery, University Hospital of the Ludwig-Maximilians-University, Munich, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Frick
mesh_terms: D000818:Animals; D000925:Anticoagulants / Q000494:pharmacology*; D002196:Capillaries / Q000187:drug effects*; D004195:Disease Models, Animal; D058752:Free Tissue Flaps / Q000098:blood supply*; D006119:Groin / Q000601:surgery; D008297:Male; D018715:Microscopy, Video; D009333:Neck / Q000601:surgery; D011486:Protein C / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D015427:Reperfusion Injury / Q000188:drug therapy* / Q000517:prevention & control; D014022:Tissue Survival / Q000187:drug effects; D014689:Venous Insufficiency / Q000188:drug therapy* / Q000517:prevention & control
chemical_list: D000925:Anticoagulants; D011486:Protein C
keywords: APC; Activated protein C; I/R; IVM; free flap; groin flap; intravital microscopy; ischemia; microsurgery; rat model; reperfusion