Hirudin as anticoagulant for cardiopulmonary bypass: Importance of preoperative renal function

Background. Recombinant hirudin is an alternative anticoagulant for cardiop ulmonary bypass in patients with heparin-induced thrombocytopenia type II. Although there is no neutralizing agent for recombinant hirudin, its fast r enal elimination enables quick cessation of bleeding after cardiopulmonary bypass. The aim of the study was to compare anticoagulant effects of recomb inant hirudin in regards to renal function in patients with heparin-induced thrombocytopenia type II. Methods. Twenty-one patients (mean age, 65 years, and range, 35 to 82 years ) underwent different complex cardiovascular procedures using recombinant h irudin as the anticoagulant for cardiopulmonary bypass. Postoperative blood loss, transfusion requirements, and hemostatic variables were compared bet ween patients with a creatinine level lower than 1.5 mg/dL (group 1, normal renal function; n = 17 patients) and those with a creatinine level greater than 1.5 mg/dL (group 2, impaired renal function; n = 4 patients). Results. The patients in group I showed no increased tendency toward postop erative bleeding. In contrast, all 4 patients in group 2 required reexplora tion for increased postoperative bleeding. They had higher activated partia l thromboplastin times and transfusion requirements postoperatively. Conclusions. If recombinant hirudin is used as the anticoagulant for cardio pulmonary bypass in patients with heparin-induced thrombocytopenia type II and impaired renal function, the risk of postoperative bleeding is increase d. (C) 2000 by The Society of Thoracic Surgeons.