Anticoagulation management in patients undergoing open heart surgery by activated clotting time and whole blood heparin concentration

OBJECTIVE: To investigate the changes in perioperative anticoagulation management using a heparin-concentration-based system (HMS), and its effect on postoperative outcome. METHODS: A total of 39 patients undergoing elective primary open heart surgery were randomly assigned to a heparin-concentration-based system approach (study group: 17 patients) or a standard ACT-based anticoagulation system (control group: 22 patients). MEASUREMENTS AND MAIN RESULTS: Patients in the study group received a statistically significant higher dose of heparin (median 29000 IU with IQR 22 500-33 500 IU versus median 19 000 IU with IQR 17 775-21 500 IU; p < 0.001) and a smaller dose of protamine (median 170 mg with IQR 145-190 mg versus median 200 mg with IQR 180-250 mg; p = 0.008) compared to the control group. Postoperative platelet count was significantly higher in the study group (164 +/- 45 x 10(9)/L versus 125 +/- 27 x 10(9)/L, p = 0.002). None of the study patients, but six patients in the control group required transfusion of blood products (p = 0.02). No differences were recorded in postoperative antithrombin activity, bleeding, and other clinical outcomes. CONCLUSION: The HMS system, by facilitating maintenance of a stable heparin concentration, and by determining an appropriate dose of protamine, is associated with reduced platelet consumption and does not increase AT-III consumption and postoperative bleeding.