Combined Regional Nafamostat and Low-Dose Systemic Heparin Anticoagulation in ECMO Patients With High Bleeding Risk: A Case Series and Safety Evaluation

Background Systemic anticoagulation with unfractionated heparin (UFH) is the standard of care during extracorporeal membrane oxygenation (ECMO). However, in patients with coagulation disorders or high bleeding risk, UFH may lead to life-threatening hemorrhage. Objective To evaluate the safety and feasibility of a dual anticoagulation strategy combining regional nafamostat mesilate with low-dose systemic UFH in high bleeding risk ECMO patients. Methods We conducted a retrospective case series of 8 ECMO patients with coagulopathy between January 2023 and December 2024 at a tertiary ICU. Patients received continuous regional nafamostat (0.5–0.75 mg/kg/h) via the ECMO circuit and low-dose UFH (4–8 U/kg/h) intravenously. Clinical outcomes, anticoagulation parameters (ACT/APTT), bleeding/thrombotic events, and oxygenator performance were evaluated. Results No thrombotic events or oxygenator-related clots were observed. Three patients experienced minor bleeding (37.5%), but none had major hemorrhage. ACT and APTT remained within acceptable ranges. The combination strategy reduced UFH requirements without compromising circuit patency. Conclusion In high bleeding risk ECMO patients, combining regional nafamostat with low-dose UFH appears to be a safe, individualized anticoagulation alternative. Prospective studies are warranted to validate these findings.