Continuous small-dose aprotinin controls fibrinolysis during orthotopic liver transplantation

Large doses of aprotinin (1,000,000-2,000,000 kallikrein inhibitor units [KIU] initial dose and a 500,000 KIU/h infusion) have been used during orthotopic liver transplantation (OLT) to reduce the incidence and severity of fibrinolysis. This double-blinded study was designed to investigate whether a small-dose infusion of aprotinin (200,000 KIU/h) would control fibrinolysis. A controlled study was undertaken to compare small-dose aprotinin with a placebo in patients undergoing OLT with veno-venous bypass. Forty-four patients were randomized either to the aprotinin group (n = 21), which received an intravenous infusion of 200,000 KIU/h without an initial dose, or to a control group (n = 23), which received normal saline. Coagulation variables, thrombelastograms, and postoperative blood drainage were measured. Blood levels of fibrin degradation products (FDP) were significantly higher in the control group (95% > 20 micrograms/mL) at the end of surgery compared to the aprotinin group (53% > 20 micrograms/mL, P < 0.01). The transfusion of cryoprecipitate units was more in the control group versus the aprotinin (12.6 +/- 12.8 vs 5.7 +/- 7.5; P < 0.04), as was the number of fresh frozen plasma units (6.6 +/- 3.5 vs 3.6 +/- 6.1; P < 0.05). We conclude that an infusion of a small dose of aprotinin can safely control fibrinolysis during liver transplantation with a concomitant reduction in transfusion of blood products.