Effects of hepatic ischemia on coagulation in primates. Application to liver transplantation

Increased fibrinolytic activity and consumption coagulopathy are common consequences of liver transplantation and are a major cause of morbidity and death. In the present investigation the effects of hepatic ischemia on the coagulation mechanism were studied in the stump-tail monkey. The results suggest that, although fibrinolytic activity is induced by both major intraabdominal operations as well as one hour of hepatic ischemia, consumption coagulopathy, presumably due to intravascular clotting, is enhanced by the revascularization of the ischemic liver, possibly because of clotting within the liver itself. Release of a plasminogen activator from the liver due to hepatic ischemia alone is not demonstrated by these studies. It is believed that the first phase of intravascular coagulation after liver transplantation is due to release of tissue activators from vascular endothelium, which may be minimized by the action of ganglionic blocking agents. The severity of fibrinolysis in this stage is aggravated by the "liverless state," in which no clearance of plasminogen activators occurs. The degree of liver injury directly affects the ability of the liver to control hypercoagulability in the second phase. Thrombus formation which we believe occurs during this phase may be minimized by use of continuous controlled heparinization.