Hemostatic variation during perioperative period of orthotopic liver transplantation without venovenous bypass

Objectives: To measure the variations of different parameters in the hemostatic system and to analyze their roles in the development of hemostatic disorder in patients with orthotopic liver transplantation (OLT) procedures routinely performed without venovenous bypass. Methods: The blood coagulation and fibrinolysis parameters were analyzed in 20 patients who underwent liver transplantation. Blood samples were drawn from the radial artery at serial time points during perioperative period. Prothrombin time (PT), activated partial thromboplastin time (aPTT), thrombin time (TT), fibrinogen, vWF, antithrombin III (AT-III), protein C (PC), tissue factor pathway inhibitor (TFPI), plasminogen (PLG), alpha(2)-antiplasmin (alpha(2)-AP), and D-dimer were analyzed. Results: Hemoglobin, platelet count, and fibrinogen were significantly decreased during anhepatic and reperfusion phases compared with preoperative values (P<0.01). VWF activity only showed significant increase during the reperfusion 60 min compared with preoperative value (P<0.05). PT, INR, aPTT, and TT were prolonged progressively, and they reached the maximum values at the beginning reperfusion 15 min compared with preoperative values (P<0.01). The AT-III, PC, TFPI, PLG, and alpha(2)-AP levels were decreased significantly and D-dimer level was elevated significantly throughout the intraoperative period. In the postoperative period, these parameters progressively returned to preoperative levels. Conclusions: In the entire process of OLT operation, coagulation defects, hyperfibrinolysis and platelet numbers decrease could develop hemostatic disorder. The data obtained in this study might contribute to a better understanding of the pathophysiology and assessment of bleeding risk in the OLT. (C) 2007 Elsevier Ltd. All rights reserved.