ECMO

Extracorporeal Membrane Oxygenation (ECMO) is a life support treatment that temporarily takes over the work of your heart and/or lungs when they are severely failing. A machine outside your body adds oxygen to your blood and removes carbon dioxide, allowing your own organs to rest and heal. It is used for critical conditions when other treatments are not enough.

What is ECMO?

ECMO, or Extracorporeal Membrane Oxygenation, is a specialized form of life support that acts as an artificial heart and lung outside your body. It circulates your blood through a machine that adds oxygen and removes carbon dioxide, similar to how your own lungs work. This process gives your severely damaged heart or lungs time to recover or allows doctors to treat the underlying condition.

The ECMO machine consists of a pump, which acts as an artificial heart, and an oxygenator, which functions as an artificial lung. Blood is drawn from your body, passes through the oxygenator to receive oxygen and release carbon dioxide, and is then warmed before being returned to you. This continuous circulation supports your body's vital functions. There are two main types of ECMO. Veno-venous (V-V) ECMO supports only the lungs, while veno-arterial (V-A) ECMO supports both the heart and lungs. The type used depends on whether your heart, lungs, or both organs need assistance. ECMO is a complex procedure performed by a highly trained medical team in an intensive care unit (ICU).

Why it's done

ECMO is performed when your heart or lungs are failing so severely that conventional medical treatments are no longer effective. It provides critical support for life-threatening conditions, giving your organs a chance to heal or serving as a bridge to other treatments like organ transplantation. It is a last-resort option for very sick patients.

Doctors may recommend ECMO for conditions such as severe pneumonia, acute respiratory distress syndrome (ARDS), or severe heart failure following a heart attack. It can also be used to support patients during cardiac arrest or as a temporary measure while awaiting a heart or lung transplant. The goal is to stabilize your condition and allow time for recovery or further intervention. ECMO is not a cure for the underlying illness but rather a life-sustaining treatment that supports your body's functions. It is considered when there is a potentially reversible cause for the organ failure or when it can bridge you to a definitive treatment. Your medical team will carefully assess if ECMO is appropriate for your specific situation.

How to prepare

Preparing for ECMO involves detailed discussions with your medical team and family members due to its critical nature. Doctors will explain the procedure, its potential benefits, and the significant risks involved. You or your legal representative will need to provide informed consent, understanding that ECMO is a complex, life-sustaining treatment for critical illness.

Because ECMO is typically used in emergency or critical situations, there may be limited time for extensive preparation. However, the medical team will ensure that you or your family understands why ECMO is necessary and what to expect. They will discuss the goals of treatment and the potential outcomes. Before starting ECMO, you will undergo various tests to assess your overall health and the extent of your organ damage. These tests help the medical team determine the best approach for your care and monitor your condition throughout the treatment. You will also be given medications, such as blood thinners, to prepare your body for the procedure.

What happens during

During ECMO, trained clinicians surgically insert large, flexible tubes called cannulas into your major blood vessels, typically in your neck or groin. These cannulas connect you to the ECMO machine, which then circulates your blood, oxygenates it, and removes carbon dioxide. You will be continuously monitored and usually kept sedated to ensure comfort and minimize movement.

Once the cannulas are in place, your blood flows from your body through the ECMO circuit. The circuit includes a pump that moves the blood and an oxygenator that acts as an artificial lung. After the blood is oxygenated and warmed, it is returned to your body through another cannula. Throughout the ECMO treatment, a specialized team of doctors, nurses, and respiratory therapists will continuously monitor your vital signs, blood tests, and the ECMO machine's settings. Adjustments are made as needed to optimize your oxygen levels and support your organs. You will likely receive medications to prevent blood clots (anticoagulants) and to keep you comfortable and still (sedation).

Recovery & timeline

Recovery from ECMO is a gradual and often lengthy process that begins with carefully reducing ECMO support (weaning) as your heart or lungs improve. After coming off ECMO, you will likely need continued intensive care and rehabilitation, including physical therapy, to regain strength. The total recovery timeline varies significantly, ranging from weeks to many months, depending on your underlying condition and overall health.

When your medical team determines that your heart or lungs are recovering, they will slowly decrease the support provided by the ECMO machine. This process, called weaning, allows your own organs to gradually take over their functions. If your body tolerates the reduced support, the cannulas will eventually be removed. After ECMO, patients often experience muscle weakness and fatigue due to prolonged bed rest and critical illness. Rehabilitation, including physical and occupational therapy, is crucial to help you regain strength, mobility, and independence. The recovery journey is unique for each person, and your medical team will provide personalized care and support throughout the process.

Risks & side effects

ECMO carries significant risks because it is used for critically ill patients whose organs are failing. Bleeding is a common risk, often due to the blood thinners (anticoagulants) necessary to prevent blood clots in the ECMO circuit. Other serious side effects can include infection, stroke, blood clots, kidney failure, and damage to blood vessels or limbs.

The need for blood thinners to prevent clots in the ECMO machine increases the risk of bleeding, which can occur internally or at the cannula insertion sites. The medical team closely monitors your blood clotting ability to manage this risk. Other potential complications include infections, which can be serious in critically ill patients, and neurological issues like stroke. Blood clots can sometimes form despite anticoagulants, leading to blockages. Kidney failure may also occur, sometimes requiring additional support like dialysis. Your medical team will continuously monitor you for these and other potential side effects and will take steps to manage them promptly.

Success rate

The success rate of ECMO varies widely and depends on many factors, including your age, overall health, and the specific condition requiring support. While ECMO can be life-saving for severe heart or lung failure, it is a last-resort treatment. It does not cure the underlying illness but provides time for your body to heal, and outcomes are generally better when the underlying condition is reversible.

ECMO is a highly specialized and resource-intensive treatment. Its effectiveness is significantly influenced by how quickly it is started after organ failure, the severity of your illness, and whether your underlying condition can improve or be treated. For some conditions, ECMO can significantly improve survival chances when other treatments have failed. It is important to understand that ECMO is a supportive measure, not a guarantee of recovery. Your medical team will discuss the potential benefits and risks specific to your situation, providing an honest assessment of the expected outcomes. They will continuously evaluate your progress and adjust your care plan accordingly.

Frequently asked questions

How long can someone stay on ECMO?

The duration of ECMO treatment varies widely, from a few days to several weeks, depending on how quickly your heart or lungs recover. It is a temporary support system, and the goal is to remove you from the machine as soon as your organs can function on their own.

Is ECMO painful?

While on ECMO, you are typically given strong sedatives and pain medications to keep you comfortable and still. This helps prevent movement that could dislodge the tubes and reduces stress on your body. Therefore, you are usually not aware of pain during the procedure itself.

What's the difference between V-A and V-V ECMO?

Veno-venous (V-V) ECMO provides support only for your lungs, helping with oxygenation and carbon dioxide removal. Veno-arterial (V-A) ECMO supports both your heart and lungs, assisting with blood circulation, oxygenation, and carbon dioxide removal.

Can I talk or eat while on ECMO?

Most people on ECMO are deeply sedated and may have a breathing tube, which prevents talking. Eating is also not possible due to sedation and the critical nature of the illness; nutrition is typically provided intravenously or through a feeding tube.

What happens if ECMO doesn't work?

If ECMO does not lead to recovery of your heart or lungs, your medical team will discuss the situation with your family. In such cases, ECMO may be discontinued, and comfort care would be provided. This difficult decision is made with careful consideration of your prognosis and wishes.

Will I have scars from ECMO?

Yes, you will likely have small scars where the cannulas (tubes) were inserted into your blood vessels, typically in your neck or groin. These incisions are usually closed with stitches after the cannulas are removed.

Sources

• MedlinePlus — ECMO
• Mayo Clinic — ECMO
• Cochrane Library — ECMO