Heparin rebound, Bleeding, Protamine, Activated coagulation time, Off-pump coronary artery bypass grafting, Surgery, RD1-811, Anesthesiology, RD78.3-87.3

Abstract Background Heparin, an anticoagulant used in cardiac surgery, can result in heparin rebound (HR), where it returns postoperatively despite being neutralized with protamine. This study was designed to investigate the prevalence of HR in patients undergoing off-pump coronary artery bypass grafting (OPCAB) and evaluate the impact of HR on their short-term outcomes. Methods HR was defined by a 10% increase in activated coagulation time (ACT) following two hours of heparin neutralization with protamine, bleeding over 200 mL/h, and abnormal laboratory coagulation examination results. We analyzed 503 OPCAB patients aged 31–80 years from September 2019 to June 2022, who were categorized into HR (n = 56) and Non-HR (n = 447) groups. The primary outcome was postoperative bleeding volume. Secondary outcomes included the incidence of postoperative reoperation for bleeding, allogenic blood transfusion incidences and volumes, and laboratory variables. Results Significant differences were observed in preoperative platelet counts (P