Extracorporeal Membrane Oxygenation (ECMO)

Extracorporeal Membrane Oxygenation (ECMO)

What is extracorporeal membrane oxygenation (ECMO)?

The extracorporeal membrane oxygenation (ECMO) machine is a heart and lung machine similar to the one used in open-heart surgery. It pumps and oxygenates a patient's blood outside the body, allowing the heart and lungs to rest.

When you are connected to an ECMO, blood flows through tubing to an artificial lung in the machine that adds oxygen and takes out carbon dioxide. The blood is then warmed to body temperature and pumped back into your body.

When is ECMO used?

ECMO treatment is used:

• For patients recovering from heart failure, lung failure or heart surgery
• As a bridge option to further treatment, when doctors want to assess the state of other organs such as the kidneys or brain before performing heart or lung surgery
• For support during high-risk procedures in the cardiac catheterization lab
• As a bridge to a heart assist device, such as a left ventricular assist device (LVAD)
• As a bridge for patients awaiting lung transplant. The ECMO helps keep tissues well oxygenated, which makes the patient a better candidate for transplant

Types of ECMO

There are two types of ECMO:

• Venoarterial (VA) ECMO. Used when a person has problems with both their heart and lungs, the VA ECMO is connected to both a vein and an artery.
• Venovenous (VV) ECMO. When the issue only affects a person's lungs, a VV ECMO is connected to one or more of their veins, usually near the heart.

USCF also uses a smaller portable ECMO device that is light enough to be carried by one person and can be transported in an ambulance or helicopter, making it possible to provide ECMO relief in emergency cases.

ECMO procedure

Being placed on ECMO requires a surgical procedure but it is usually done in a patient's room. The patient is sedated and given pain medication and an anti-coagulant to minimize blood clotting. A surgeon, assisted by an operating room team, inserts the ECMO catheters into the appropriate blood vessels. An X-ray is then taken to ensure the tubes are in the right place.

Usually, a patient on the ECMO pump will also be on a ventilator, a mechanical breathing support device, which helps the lungs to heal. While on ECMO, the patient will be monitored by specially trained nurses and respiratory therapists, as well as the surgeon and surgical team. Since patients are sedated and have a breathing tube in place, supplemental nutrition will be provided either intravenously or through a nasal-gastric tube.

Medications to support ECMO

While on ECMO, a patient may be given certain medications including:

• Heparin to prevent blood clots
• Antibiotics to prevent infections
• Sedatives to minimize movement and improve sleep
• Diuretics to help the kidney get rid of fluids
• Electrolytes to maintain the proper balance of salts and sugars
• Blood products to replace blood loss

Removing the ECMO device

Discontinuing ECMO requires a surgical procedure to remove the tubes. Multiple tests are usually done before stopping ECMO therapy to confirm that the heart and lungs are ready.

Once the ECMO cannulas (the tubes used to carry blood out of and back into the body) are removed, the vessels will need to be repaired. This can be done either in the patient's room or in the operating room. The doctor will use small stitches to close the spot where the tubes were placed. Patients are asleep and monitored throughout this process.

Even after ECMO is discontinued, patients may still need to be on a ventilator.

Risks of ECMO

ECMO does carry risks, including:

• Bleeding, due to the medication that's given to prevent blood from clotting in the tubing
• Infection at the sites where the tubes enter the body
• Transfusion problems, since a person on ECMO is given blood products
• Small clots or air bubbles forming in the tubing
• Increased chance of stroke