What is ECMO

Center for Acute Respiratory Failure

Extracorporeal membrane oxygenation (ECMO) is one of several terms used to describe a circuit outside the body ("extracorporeal") that directly oxygenates and removes carbon dioxide from the blood. ECMO functions as an artificial lung working in addition to the patient's own failing lungs.

An illustration of how ECMO works.
Click image to enlarge.

With most approaches to ECMO for respiratory failure, a catheter is placed in a central vein, usually near the heart. A mechanical pump draws blood from the vein into the circuit, where the blood passes along a membrane (referred to as an "oxygenator" or "gas exchanger"), providing an interface between the blood and freshly delivered oxygen.

ECMO with single site cannulation.
Click image to enlarge.

The blood may be warmed or cooled as needed, and is returned either to a central vein ("veno-venous ECMO") or to an artery ("veno-arterial ECMO"). Veno-venous ECMO provides respiratory support alone, while veno-arterial ECMO provides both respiratory and hemodynamic (blood pressure) support. Examples of scenarios where ECMO may benefit patients include the following:

ECMO with two site cannulation.
Click image to enlarge.

If a patient has life-threatening acute respiratory failure with profound gas exchange abnormalities, ECMO may be used as salvage therapy to rescue the patient.
ECMO may also be used in patients with ARDS who would benefit from lung-protective ventilation strategies but who are unable to tolerate such strategies.
ECMO is used in select patients with severe hypercarbic respiratory failure (levels of carbon dioxide in the blood that are too high).
ECMO may be used in patients with chronic lung disease who are already listed for lung transplantation at NewYork-Presbyterian/Columbia. This approach is called "bridge-to-transplantation."