Extracorporeal Membrane Oxygenation (ECMO) is a treatment in which blood is oxygenated and waste is removed before being pumped back into the bloodstream. ECMO is often used as a short-term option for patients with massive heart attacks, or those who experience a sudden significant decrease in heart function and may suffer end-organ damage if not treated immediately. This treatment works for the heart, lungs or both.
ECMO is used only after medications and a breathing machine (ventilator) have failed. During ECMO, blood flows through tubes and is pushed along by a pump. This flow may be high at the beginning of ECMO insertion, meaning the machine is doing most of the work of the heart. Patients may appear to be better, but are still very sick and dependent on the ECMO machine to keep them alive.
A Scripps multi-disciplinary team cares for patients receivng ECMO. The intensive care unit physicians and staff may work closely with other experts in cardiology, neurology, infectious disease, pulmonology or other specialties. In addition, a perfusionist oversees the ECMO circuit and a respiratory therapist oversees the breathing machine.
Scripps cardiac experts have successfully used ECMO to help patients recover from major heart attacks, acute heart failure and cardiogenic shock from a variety of causes. ECMO is a life-saving measure usually performed in the operating room, but it can also be used in the emergency room, a hospital patient room or outside the hospital.
There are two types of ECMO: VV and VA. The terms VV and VA refer to the blood vessels used in the treatment.
In VV ECMO, one or more tubes are placed in a vein. This type of ECMO is used when there are lung problems only. Sometimes, a person may start on VV and need to be switched to VA.
In VA ECMO, a tube is placed in both a vein and an artery. VA ECMO is used when there are problems with both the heart and lungs. The treatment helps the heart and lungs rest and recover.
Because blood must be kept from clotting in the tubing, bleeding may occur. Steps are taken to slow any bleeding that happens. If bleeding increases, surgery may be necessary. If the bleeding becomes too great, ECMO may need to be stopped.
Any time a tube is placed in the body, especially a blood vessel, infection is a risk. Antibiotics are given, if needed.
A person on ECMO will need blood products. When blood is given, side effects can occur. In most cases, side effects can be addressed with medication.
Small clots or air bubbles
Entering the blood from the tubes, small clots or air bubbles can sometimes cause injury to other parts of the body. These can even be fatal.
Many lab tests are performed before and during ECMO, including:
- CT scans to look at the brain, chest or abdomen
- X-rays to look at the lungs and the location of the tubes in the body
- Blood gases (ABG) to check the oxygen and carbon dioxide levels in the blood
- Echocardiograms (ultrasound) to examine different areas of the heart and how well they are working
While on ECMO, numerous medications are given, including:
- IV Infusions of various medications to help with blood pressure and heart function
- Heparin to prevent blood clots from forming in the ECMO tubing
- Antibiotics to prevent or treat infection
- Sedatives and pain medicine to prevent agitation, limit pain, improve sleeping and promote comfort
- Diuretics to help the kidneys produce urine
- Electrolytes to keep the body in balance
- Blood products to replace blood loss
Patients are placed on ECMO because the heart or lungs or both can no longer function well enough to keep them alive without medical intervention. Weaning from the ECMO machine is very unpredictable and, unfortunately, does not always work. If weaning is successful, the ECMO machine tubing will be removed in the operating room by a surgeon.