Preoperative antithrombin supplementation in cardiac surgery: a randomized controlled trial.

OBJECTIVES: Purified antithrombin supplementation in cardiac surgery has been suggested for the treatment of heparin resistance and the prevention of thromboembolic complications. This study is a randomized controlled trial of preoperative purified antithrombin supplementation, with the primary end point of avoiding low (<58%) postoperative antithrombin activity levels and secondary end points including avoidance of heparin resistance, clinical outcome, and safety end points. METHODS: Two hundred patients were randomly allocated to the antithrombin group and the control group. Patients in the antithrombin group received a dose of purified antithrombin to reach an antithrombin activity value of 120%, whereas patients in the control group did not receive antithrombin. RESULTS: The antithrombin activity values were significantly higher in the antithrombin group at all postoperative determinations until discharge. Antithrombin activity levels