Background
Considerable variability persists in coagulation management during cardiopulmonary bypass (CPB) supported cardiac surgery. This survey aimed to describe contemporary reported practices across international settings.

Methods
A cross-sectional, web-based survey was conducted among cardiac anesthesiologists, perfusionists, cardiac surgeons, and intensivists. The expert-developed and pilot-tested 19-item questionnaire explored six domains of CPB-associated coagulation and transfusion management: (1) heparin administration and activated clotting time monitoring; (2) protamine dosing and timing; (3) autotransfusion and shed-blood management; (4) antithrombin monitoring and supplementation; (5) coagulation monitoring and transfusion practices; and (6) institutional quality-monitoring capabilities. Responses were analyzed descriptively, with counts, percentages, and item-specific denominators reported according to response availability.

Results
A total of 419 respondents initiated the survey, of whom 319 (76%) completed all mandatory items. Respondents represented 40 countries. Public or university hospitals accounted for 78% of reported practice settings. Initial heparin doses of 300-400 IU/kg were most common, and ACT targets were divided between 401 480 s (44%) and >480 s (43%). Heparin concentration-guided monitoring was reported routinely by 9% of respondents and selectively by 14%, whereas 72% reported no use of a Hepcon® heparin management system. The most frequently reported protamine reversal ratio was 1 mg per 100 IU of heparin (40%), whereas 38% reported individualized or other dosing approaches. Routine availability of an autotransfusion system was reported by 61%, and 81% reported its use to process residual CPB circuit blood. Antithrombin activity measurement was reported by 20% of respondents. Among respondents reporting monitoring, supplementation was most commonly triggered when the ACT failed to reach its target or when laboratory-measured antithrombin activity was below the reference range.

Conclusion
Reported practices in CPB-associated coagulation management varied substantially, indicating 3 persistent gaps between guideline-supported strategies and their implementation. Harmonized protocols, center-level benchmarking, and prospective evaluation are needed to improve comparability across institutions and support patient safety.