Increased fibrinolysis in orthotopic but not in heterotopic liver transplantation: the role of the anhepatic phase

Abstract

The major cause of increased tissue‐type plasminogen activator (t‐PA) activity during orthotopic liver transplantation (OLT) is still unclear. Both lack of hepatic clearance of t‐PA in the anhepatic period and/or increased endothelial release from the graft upon reperfusion have been suggested. Heterotopic liver transplantation (HLT) avoids resection of the host liver and is therefore a useful model to differentiate these two possibilities. The fibrinolytic system was evaluated in ten patients with OLT and in 18 patients with HLT. A marked increment in t‐PA activity was observed during the anhepatic period of OLT, which rapidly normalized after reperfusion. In contrast t‐PA activity levels remained normal in HLT. As a reflection of the increased t‐PA activity fibrin degradation products were markedly elevated during OLT and plasminogen and alpha2‐antiplasmin decreased simultaneously during the anhepatic period. In conclusion, the lack of hepatic clearance during the anhepatic period is the most important factor in the evolution of increased t‐PA activity during OLT.