C1-esterase inhibitor following cardiopulmonary bypass: evaluation of coagulation parameters - a preliminary report

Abstract
This study was designed to evaluate the effects of C1-esterase inhibitor (C1-INH) on haemostasis and blood loss in routine cardiopulmonary bypass (CPB). To determine whether or not C1-INH reduces blood loss or transfusion requirements after routine CPB, we randomized 20 patients to receive double-blind either C1-INH (15 IU/kg over 10 minutes intravenously) or placebo following heparin administration. The two groups were similar in age, sex, prior salicylate use and time on CPB. At 30 minutes from the beginning of CPB and postprotamine, factor XII, factor XI, C1-INH and prekallikrein activity were significantly higher (p < 0.05) than in the placebo group. No manifestations of hypercoagulability were seen in either group. Despite this haemostatic effect, patients treated with C1-INH had similar postoperative blood loss to the placebo group and similar blood transfusion requirements. We conclude that routine use of C1-INH in CPB is unwarranted.