Comparative effects of small and large aprotinin doses on bleeding during orthotopic liver transplantation.

Large prophylactic doses of aprotinin efficiently reduce blood loss during orthotopic liver transplantation (OLT). Small doses of aprotinin are usually used to treat fibrinolysis. However, no studies have investigated the benefit of prophylactic administration of a smaller dose of aprotinin during liver transplantation. We compared two methods of aprotinin therapy on transfusion outcome in liver transplant patients in a prospective study of 199 patients undergoing OLT who were randomized to large or small prophylactic doses of aprotinin during the transplant procedure. In the large-dose group (n = 94) an initial dose of 2,000,000 kallikrein inactivation units (KIU) was followed by infusion of 500,000 KIU/h until the patient's return to the intensive care unit. In the small-dose group (n = 95), an initial dose of 500,000 KIU was followed by an infusion of 150,000 KIU/h. Outcome measurements included intraoperative transfusion requirements (packed red blood cells, fresh frozen plasma, platelets, intraoperative salvage) and postoperative hematologic values. There were no differences in transfusion requirements in the two groups of patients. Patients treated with low-dose aprotinin had slightly higher postoperative fibrinogen concentrations. Large-dose aprotinin therapy does not appear to offer additional benefit compared to low-dose aprotinin administration.