How does ECMO work?
Dr. Hudak: ECMO is an external heart-lung bypass, similar to what is used to support patients during open heart surgery. Basically, it is used in patients whose heart and/or lungs have failed sufficiently that the usual treatments – ventilators, oxygen, vasopressors, and so forth – are no longer effective. The ECMO circuit withdraws blood from the body, circulates the blood through an oxygenator which adds oxygen to the blood while removing carbon dioxide, rewarms the blood, and then returns blood back to the systemic circulation. So, ECMO can temporarily replace the functions of both the heart and the lungs. How is the ECMO device different from a ventilator? Dr. Hudak: A ventilator is a machine that assists the lungs to do their job. A ventilator applies positive pressure to the lungs, which by itself is an abnormal event. When people breathe naturally, they generate a negative pressure, so a positive pressure can be injurious to the lungs. ECMO allows you to avoid excessive ventilat
