Antithrombin III transfusion in patients with hepatic cirrhosis.

This study was designed to examine the effect of selective correction of antithrombin III activity on the increased turnover of fibrinogen, which occurs in patients with liver cirrhosis supposedly due to disseminated intravascular coagulation. Human antithrombin III concentrates were therefore transfused in seven patients with cirrhosis and antithrombin III deficiency (less than 80%). Fibrinogen half-life and the fractional catabolic rate constant were calculated from the turnover of 125I-fibrinogen which was represented by a two-compartment model. Prior to antithrombin III transfusion, 125I-fibrinogen half-life was 76.7 +/- 15.2 h and the fractional catabolic rate constant was 0.33 +/- 0.11 of the plasma fibrinogen pool per day. In six healthy adult controls these values were significantly different: 109.4 +/- 8.8 h and 0.19 +/- 0.01 respectively. Correction of antithrombin III activity with human antithrombin III concentrate reduced the increased turnover of radiolabelled fibrinogen to normal. The 125I-fibrinogen half-life became 108.4 +/- 17.6 h and the fractional catabolic rate constant decreased to 0.23 +/- 0.06. These observations indicate that decreased antithrombin III activity contributes in an important way to the increased 125I-fibrinogen turnover in patients with cirrhosis and this might reflect intravascular coagulation.