Thromboelastography for monitoring prolonged hypercoagulability after major abdominal surgery

Despite clinical and laboratory evidence of perioperative hypercoagulabilit y, there are no consistent data evaluating the extent, duration, and specif ic contribution of platelets and procoagulatory proteins by in vitro testin g. We tested the hypothesis that the parallel use of standard and abciximab -cytochalasin D-modified thromboelastography (TEG(R)) can assess 7 days' po stoperative hypercoagulability and can estimate the independent contributio n of procoagulatory proteins and platelets. Thromboelastograms were perform ed before surgery, at the end of surgery, 6 h after surgery, and on postope rative days 1,2,3, and 7; they were analyzed for the reaction time and the maximal amplitude (MA). We calculated the elastic shear modulus of standard MA (G(t)) and modified MA (G(c)), which reflect total clot strength and pr ocoagulatory protein-component, respectively. The difference was an estimat e of the platelet component (G(p)). There was a 10% perioperative increase of standard MA, corresponding to a 50% increase of G(t) (P < 0.0001) and an 86%-90% contribution of the calculated G(p) to G(t). We conclude that seri al standard and modified thromboelastography may reveal prolonged postopera tive hypercoagulability and the independent contribution of platelets and p rocoagulatory proteins to clot strength.