ID:105 FC-PC1-3 Long-term V-V ECMO management in patients suspected of having HIT

Background: Veno-venous extracorporeal membrane oxygenation (V-V ECMO) is an established lifesaving therapy for severe respiratory failure; however, bleeding and thrombosis remain major complications requiring optimal anticoagulation. We report a prolonged V-V ECMO case complicated by suspected heparin-induced thrombocytopenia (HIT) and rare Rh-negative blood type. Clinical Course: A man in his 30s with blood type O Rh-negative (height 157 cm, weight 55 kg, body surface area 1.50 m2) presented with fever, hypoxemia, and impaired consciousness. Pneumonia and influenza infection were suspected. Respiratory failure rapidly progressed with mediastinal emphysema and bilateral pneumothorax. Despite mechanical ventilation, oxygenation did not improve, and V-V ECMO was initiated. On day 12, marked thrombocytopenia and elevated fibrin degradation products suggested HIT. Anticoagulation was changed from heparin to argatroban, and the circuit was switched from a heparin-coated to a polymer-coated circuit. Although activated clotting time (ACT) and activated partial thromboplastin time (APTT) remained within acceptable ranges, thrombus formation in the oxygenator persisted. Nafamostat mesylate was added for combined anticoagulation. Due to limited availability of Rh-negative blood products, four planned oxygenator exchanges were performed. ECMO support continued for 51 days, after which the patient was successfully weaned and discharged home without respiratory support. Discussion: Anticoagulation management during ECMO is particularly challenging in patients with suspected HIT. In addition, limited transfusion resources in Rh-negative patients increase risks during prolonged support. Conclusion: Strategic anticoagulation adjustment and planned circuit management enabled successful long-term V-V ECMO in a patient with suspected HIT and rare blood type. Careful transfusion planning is essential in similar cases.