ENDOGENOUS HEPARIN-LIKE SUBSTANCES SIGNIFICANTLY IMPAIR COAGULATION IN PATIENTS UNDERGOING ORTHOTOPIC LIVER-TRANSPLANTATION

Orthotopic liver transplantation (OLT) is associated with severe bleed ing, especially after reperfusion of the grafted liver. Heparin releas ed from the liver graft contributes to postreperfusion coagulopathy. A lthough patients with liver cirrhosis have increased levels of endogen ous heparinoids, the role of these substances during liver transplanta tion is unclear. Therefore, we performed native and heparinase-modifie d thrombelastography (TEG) in 72 patients undergoing OLT. TEG was perf ormed at skin incision, 10 min before and 10 min after clamping of the vena cava, 10 min before and 10 min after graft perfusion, and at the end of surgery. Heparinase-modified TEG compared with native TEG demo nstrated heparin activity. In contrast to other investigations, we fou nd significant heparin effects before reperfusion, although patients r eceived no exogenous heparin. These heparin effects were greater in pa tients with cirrhosis compared with patients with cancer as the underl ying disease leading to OLT. Administration of coagulation factors is the usual treatment of coagulopathies during OLT. The comparison of na tive versus heparinase-modified TEG can distinguish between heparin ac tivity or coagulation factor deficiency as a cause of bleeding complic ations and provides a rational approach to the treatment of bleeding d uring OLT. Implications: Impaired coagulation function, contributed to by heparin or heparin-like substances, is frequently observed after re perfusion of a transplanted liver. This study demonstrates that a hepa rinase-modified thrombelastography can identify significant heparin ef fects in the absence of exogenous heparin administration in patients u ndergoing liver transplantation.