PRS PSRC Podium Proofs 2016
Eric D. Wang, MD, Amanda S. Conroy, BA, Kaitlin Z. Gee, BS, Benedict Del Buono, BA, Sarosh N. Zafar, MD, Michael J. Terry MD, Scott L. Hansen MD, Mitchell J. Cohen, MD, Hani Sbitany, MD, Esther A. Kim, MD
From the University of California, San Francisco, San Francisco, Calif.
PURPOSE: Although thrombotic complications are devastating, reconstructive microsurgeons lack a useful means to quantify the thrombotic potential in hemostatic pathways. Impedance aggregrometry (IA) is a novel means to rapidly measure platelet function, with previously demonstrated utility in interventional cardiology. We investigated its microsurgical application as an early predictor of thrombotic flap complications and its utility in monitoring antiplatelet therapy.
METHODS: After obtaining institutional review board approval, consecutive patients undergoing microsurgical flap reconstruction were enrolled in our prospective observational study. Serial phlebotomy was performed preoperatively and postoperatively after standardized administration of aspirin. We performed Multiplate IA (Roche/Genentech, South San Francisco, Calif.) utilizing various platelet agonists as well as complete blood count and conventional coagulation (PT/PTT) testing on all samples. Outcomes included thrombosis, reoperation, and significant bleeding postoperatively. Analyses were performed with Stata version 14 with Student’s t and Fisher’s exact tests.
RESULTS: Interim analyses were performed after enrollment of 20 subjects. Six subjects experienced intraoperative or postoperative anastomotic thromboses not attributable to surgical technique. These patients were younger (40 vs 56.6 years, P = 0.021) but were otherwise well matched. Platelet aggregation to the arachidonic acid agonist demonstrated decreased response (mean change, −13.8 vs −33.1 AU, P = 0.031) and greater residual platelet activity (mean, 46.1 vs 20.7 AU, P = 0.032) in the thrombosis group despite standard aspirin treatment.
CONCLUSIONS: IA identifies a thrombotic flap phenotype, characterized by high-residual postoperative platelet activity and low response to antiplatelet therapy. Platelet function monitoring has significant potential to predict thrombotic risk and drive individualized anticoagulation to prevent flap loss.