Alterations in coagulation following major liver resection

Abstract

The international normalised ratio is frequently raised in patients who have undergone major liver resection, and isassumed to represent a potential bleeding risk. However, these patients have an increased risk of venous thromboem-bolic events, despite conventional coagulation tests indicating hypocoagulability. This prospective, observational studyof patients undergoing major hepatic resection analysed the serial changes in coagulation in the early postoperativeperiod. Thrombin generation parameters and viscoelastic tests of coagulation (thromboelastometry) remained withinnormal ranges throughout the study period. Levels of the procoagulant factors II, V, VII and X initially fell, but Vand X returned to or exceeded normal range by postoperative dayfive. Levels of factor VIII and Von Willebrand fac-tor were significantly elevated from postoperative day one (p<0.01). Levels of the anticoagulants, protein C andantithrombin remained significantly depressed on postoperative dayfive (p=0.01). Overall, the imbalance betweenpro- and anticoagulant factors suggested a prothrombotic environment in the early postoperative period.