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 29 000 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± 45×109/L versus 125±27 × 109/L, p=0.002). None of the study patients, but six patients in the control group required transfusion of blood pr...