Affiliations: [a] Hand Surgery, Plastic Surgery and Aesthetic Surgery, University Hospital of the Ludwig-Maximilians-University, Munich, Germany | [b] Consultant for Lymphology of the Surgical Clinic Munich Bogenhausen, Munich, Germany
Correspondence:
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Correspondence to: J. Wallmichrath, M.D., Hand Surgery, Plastic Surgery and Aesthetic Surgery, University Hospital of the Ludwig-Maximilians University, Marchioninistrasse 15, D-81377 Munich, Germany. Tel.: +49 89 7095 3502; Fax: +49 89 7095 6505; Jens.Wallmichrath@med.uni-muenchen.de
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.
Keywords: Activated protein C, APC, free flap, groin flap, microsurgery, intravital microscopy, IVM, ischemia, reperfusion, I/R, rat model
