Thromboelastographic changes in liver and pancreatic cancer surgery: hypercoagulability, hypocoagulability or normocoagulability?

Background and objective Despite clinical and laboratory evidence of perioperative hypercoagulability, alterations in haemostasis after potentially haemorrhagic oncologic surgery are difficult to predict. This study aims to evaluate the entity, the extent and the duration of perioperative coagulative alterations following pancreas and liver oncologic surgery, by the use of both routine tests and thromboelastogram (TEG). Methods Fifty-six patients undergoing liver (n=38) and pancreatic (n=18) surgery were studied. The coagulation profile was evaluated by platelet count, prothrombin time-international normalized ratio, activated partial thromboplastin time, antithrombin III and TEG at the beginning, at the end of the operation and on postoperative days 1, 3, 5 and 10. Results All preoperative coagulative screening and TEG traces were normal before incision. In the postoperative period of the liver and pancreas groups, despite an increase in prothrombin time-international normalized ratio, a reduction in antithrombin III and platelet count and normal activated partial thromboplastin time and fibrinogen, TEG evidenced a normocoagulability in the liver group, with a major tendency towards hypocoagulability in the pancreas group, as evidenced by a transient increase in R-time and K-time between postoperative days 1 and 3. During the study period, four cases of pulmonaryembolism, resolved with heparin infusion, were recorded, in the absence of laboratory and thromboelastographic evidence of hypercoagulability. Conclusion Despite laboratory tests evidencing hypocoagulability in both groups, TEG traces showed a normocoagulability in liver resections, whereas a transient thromboelastographic hypocoagulability was evident in patients undergoing pancreas surgery. The discrepancy between laboratory values and thromboelastographic variables was even more evident in patients undergoing major liver resections compared with minor ones. Our study supports the role of thromboelastography, despite its limitations, as a valuable tool for the evaluation of the perioperative whole coagulation process and hypercoagulability changes and to increase patient safety through better management of antithrombotic therapy. Eur J Anaesthesiol 2010;27:608-616