Evaluation of the impact of HMS Plus on postoperative blood loss compared with ACT Plus in cardiac surgery.

Background: The standardized management of anticoagulation during the cardiopulmonary bypass seems inaccurate because of patients and surgeries variability. This study evaluates if an individualized management of heparin and protamine guided by the HMS Plus system during cardiopulmonary bypass could reduce postoperative blood loss.
Methods: We conducted a prospective, controlled, unblinded, single-center study. One-hundred and eighthy-eight patients operated for cardiac surgery were included. Patients were divided in ACT Plus group (standardized approach) and HMS Plus group (individualized approach). The primary outcome was blood-loss volume during the first 24 postoperative hours. The main secondary outcomes were the need for allogeneic blood transfusions and the final protamine/heparin ratio.
Results: There was no difference between the two groups for baseline characteristics. Medium blood-loss volume in the ACT Plus group was 522±260 mL vs. 527±255 mL in the HMS Plus group (P=0.58). The final protamine/heparin ratio in the ACT Plus group was 0.94±0.1 vs. 0.58±0.1 in the HMS Plus group (P<0.0001). The transfusion rate during surgery in the ACT Plus group was 25% vs. 14% in the HMS Plus group (P=0.09).
Conclusions: HMS Plus did not reduce the mean blood-loss volume during the first 24 postoperative hours compared with ACT Plus. Its utility for potential transfusion rate reduction remains to be proven.