Physiology II: Venoarterial ECMO

At the core, venoarterial (VA) extracorporeal membrane oxygenation (ECMO) aims to restore blood flow and perfusion to the body in the setting of a heart that can no longer provide the requisite cardiac output to meet the metabolic demands of the tissues. This may be for a host of diverse etiologies that in extremis lead to profound heart failure refractory to traditional medical therapies and resulting in cardiogenic shock. Understanding normal cardiac physiology is key to understanding the goals and indications for VA ECMO support. Management on VA ECMO balances maximizing delivery of oxygen with the risk such as coagulopathy, left ventricular distention, and hypoxia. Certain situations may utilize other mechanical circulatory devices, combined forms of extracorporeal support, and hybrid or parallel ECMO configuration.