PMID- 38264767 OWN - NLM STAT- MEDLINE DCOM- 20240318 LR - 20240318 IS - 1537-2995 (Electronic) IS - 0041-1132 (Linking) VI - 64 IP - 3 DP - 2024 Mar TI - Protamine dosing and its impact in cardiac surgery transfusion practice-A retrospective bi-institutional analysis. PG - 467-474 LID - 10.1111/trf.17730 [doi] AB - BACKGROUND: Bleeding after cardiac surgery is common and continues to require 10-20% of the national blood supply. Transfusion of allogeneic blood is associated with increased morbidity and mortality. Excessive protamine in the absence of circulating heparin after weaning off CPB can cause anticoagulation and precipitate bleeding. Hence, adequate dose calculation of protamine is crucial yet under evaluated. STUDY DESIGN: Retrospective cohort study. METHODS: We conducted a retrospective bi-institutional analysis of cardiac surgical patients who underwent cardiopulmonary bypass (CPB)-assisted cardiac surgery to assess the impact of protamine dosing in transfusion practice. Total 762 patients were identified from two institutions using electronic medical records and the Society of Thoracic Surgery (STS) database who underwent cardiac surgery using CPB. Patients were similar in demographics and other baseline characteristics. We divided patients into two groups based on mg of protamine administered to neutralize each 100 U of unfractionated heparin (UFH)-low-ratio group (Protamine: UFH 0.8). RESULTS: We observed a higher rate of blood transfusion required in high-ratio group (ratio >0.8) compared with low-ratio group (ratio