Abstract
Regarding extracorporeal membrane oxygenation (ECMO) support against hemorrhagic conditions, there seems to be a dilemma when deciding between maintaining the circuit patency by systemic anticoagulation and increasing the risk of bleeding. We herein report two cases of diffuse alveolar hemorrhage (DAH) caused by myeloperoxidase (MPO) anti-neutrophil cytoplasmic autoantibody-associated vasculitis (AAV) successfully treated with venovenous (VV)-ECMO support, both initially started without systemic anticoagulation. Under anticoagulation-free ECMO management, we should consider the shortcomings of frequent circuit exchange and hemorrhagic diathesis related to circuit-induced disseminated intravascular coagulation (DIC).