ECMO: What You Need to Know

Medically Reviewed by Paul Boyce, MD on November 04, 2023
3 min read

ECMO stands for extracorporeal membrane oxygenation. An ECMO machine takes blood from your veins, pumps it outside the body (extracorporeal), removes carbon dioxide, adds oxygen (oxygenation), and returns it to your body. This process takes some of the workload off your heart or lungs or both.

There are two main types of ECMO treatments. Both remove oxygen-starved blood from your veins:

  • Venovenous (VV) ECMO returns oxygenated blood back to the veins, where it passes through your lungs. Doctors use it when there are problems with your lungs but not your heart.
  • Venoarterial (VA) ECMO returns blood to the arteries. It doesn’t pass through your lungs. Doctors typically use this when there are problems with both your heart and lungs.

A surgical team will put tubes into large veins or arteries in your chest, neck, legs, or groin. You might hear the doctor call the tubes cannulae and the process cannulation. They typically do this in your hospital room. First, you get medicine to block pain, prevent blood clotting, and make you sleepy (you’ll hear this called sedation). Then a surgeon puts the tubes in place. Finally, the team takes an X-ray to make sure the tubes are in the right place.

If you need ECMO, you’re probably already using a machine that helps you breathe called a ventilator. Specially trained nurses and breathing therapists will keep an eye on your progress along with your surgical team. They’ll keep track of your blood pressure and heart rate and regularly test your blood levels of both oxygen and carbon dioxide.

You shouldn’t feel serious pain or discomfort when the tubes are put in place or while the ECMO machine does its work. You’ll be getting medicine to make you sleepy while you’re on ECMO. But you may be awake enough to interact and talk, as long as you’re not on a ventilator.

You might need ECMO treatment if:

  • Your lungs can’t get enough oxygen to the body even with extra oxygen.
  • Your lungs can’t get rid of enough carbon dioxide even with a ventilator.
  • Your heart can’t move enough blood through your body.
  • Your heart and lungs need help as you wait for an organ transplant.

ECMO treatment doesn’t cure disease or injury. It’s a tool to help support your body as your health care team tries to fix the underlying problem, which could be long-term disease like COPD, an infection like COVID-19, or even trauma from an accident.

In general, your health care team will try to remove you from the ECMO machine as soon as possible, perhaps after just a few hours. Some people need it for longer. Times can range from several days to weeks. For some people, stopping ECMO use would result in death.

ECMO treatment has two major risks:

  • Bleeding. It affects up to a third of people on ECMO and may be serious. Blood thinning meds prescribed for ECMO can add to the problem. It could result from surgical wounds or other causes. You may need surgery to find and fix the problem and look for bleeding into body cavities (hemorrhaging).
  • Blood clots: These can break loose and go to your lungs or brain, which can be life-threatening. Though blood clots affect up to 70% of people on ECMO, your health care team can usually prevent problems by keeping a close watch on you and quickly treating clots that form either in your body or in the ECMO machine’s tubes.

You might also get an infection where the tubes enter your body, and your risk of stroke could go up.