The appearance of donor heparin in the recipient after reperfusion of a liver graft.

The release of heparin has been mentioned as one of the causes of hypocoagulability after reperfusion of the liver graft. It has been ascribed to endogenous heparin released from the donor liver or to exogenous heparin in the preservation fluid that is released into the recipient after sequestration into the graft during preservation. The aim of this study was to investigate whether systemic administration of heparin to the donor before the hepatectomy contributes to the appearance of heparin in the recipient after reperfusion. We studied 20 patients undergoing an auxiliary heterotopic liver transplantation; 15 donors had received heparin immediately before circulation arrest (median 300 IU/kg body weight), but 5 had not. The thrombin time (TT), activated partial thromboplastin time (aPTT), and heparin neutralization test were determined at several intervals during the transplantation.

Intravascular coagulation in liver transplantation--is it present or not? A comparison between orthotopic and heterotopic liver transplantation.

UNLABELLED: It is still not clear whether disseminated intravascular coagulation (DIC) contributes to the hemostatic disturbances in orthotopic liver transplantation (OLT). Theoretically the lack of hepatic clearance of procoagulant factors during the anhepatic period and the release of thromboplastic material from the graft might trigger DIC. During heterotopic liver transplantation (HLT) the host liver is left in situ and procoagulant factors may still be cleared; DIC, if present, may not occur until after reperfusion. The aim of the present study was to gain more insight into the underlying mechanism of the coagulation changes during liver transplantation by comparison of OLT and HLT. Thrombin-antithrombin-III complexes (TAT), and indicator of thrombin generation, fibrin degradation products (FbDP) and routine clotting times were assayed in 12 OLTs, 18 HLTs and in a control group of 10 partial hepatic resections (PHR). TAT increased dramatically after reperfusion to 136 micrograms/l in OLT and to 94 micrograms/l in HLT (p n.s.). In contrast, FbDP levels increased only in OLT, to a maximum of 13.8 micrograms/ml. Routine clotting times changed mildly and similarly in both OLT and HLT. CONCLUSIONS: Graft reperfusion triggers excessive thrombin formation, but there are no other signs of subsequent DIC. Any thrombin formed is probably rapidly inhibited by antithrombin-III. The rise in FbDP during OLT is the result of increased fibrinolysis, which occurred only in OLT and not in HLT.

[Criteria for and results of liver transplantation in patients with acute liver insufficiency]. / Criteria voor en resultaten van levertransplantatie bij patiënten met acute leverinsufficiëntie.

OBJECTIVE: Evaluation of the results of emergency liver transplantation in patients with acute liver failure. DESIGN: Analysis of 25 patients with acute liver failure. SETTING: University Hospital Rotterdam Dijkzigt. METHOD: Twenty-five patients with acute liver failure were admitted to the Intensive Care Unit in January 1989-May 1993. Patients were selected for emergency liver transplantation according to the Clichy criteria (presence of confusion or coma and factor V activity less than 20-30%). RESULTS: Liver transplantation was indicated in 17 patients and performed in 13. The 1-year survival rate in patients with a liver transplant was 85%. Four patients with an indication for liver transplantation, but who could not be transplanted died. All 8 patients without an indication for emergency liver transplantation survived. CONCLUSION: Survival after liver transplantation for acute hepatic failure is now about 80%; the Clichy criteria appear to be helpful in selecting patients with acute hepatic failure for liver transplantation.

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

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.

Increased tissue-type plasminogen activator activity in orthotopic but not heterotopic liver transplantation: the role of the anhepatic period.

The major cause of the increased tissue-type plasminogen activator activity during orthotopic liver transplantation is still unclear. Both the lack of hepatic clearance of tissue-type plasminogen activator in the anhepatic period and increased endothelial release from the graft on reperfusion have been proposed as the major causes. Heterotopic liver transplantation avoids the resection of the host liver and is a useful model to help differentiate between these two possibilities. In this study the fibrinolytic system was evaluated in 10 orthotopic liver transplantations, 18 heterotopic liver transplantations and a control group of 10 partial hepatic resections. A marked increment in tissue-type plasminogen activator activity, from 0.2 to 5.2 IU/ml (p less than 0.02), was observed during the anhepatic period of orthotopic liver transplantation, which rapidly normalized after reperfusion. In contrast, tissue-type plasminogen activator activity levels remained normal in heterotopic liver transplantation and partial hepatic resections. In orthotopic liver transplantation and in heterotopic liver transplantation no increase occurred in tissue-type plasminogen activator activity after reperfusion. The first venous hepatic outflow after reperfusion did not contain elevated tissue-type plasminogen activator activity levels. Plasma degradation products of fibrin and fibrinogen increased during the anhepatic period of orthotopic liver transplantation (from 2.60 to 8.80 micrograms/ml [p less than 0.008] and from 0.40 to 1.60 micrograms/ml [p less than 0.04], respectively) and remained elevated thereafter. In heterotopic liver transplantation and partial hepatic resections these levels remained low. In conclusion, the lack of hepatic clearance during the anhepatic period is probably the most important factor in the evolution of increased tissue-type plasminogen activator activity during orthotopic liver transplantation.