ECMO Explained: Recipients, Procedure, and Additional Information
In critical situations where the heart and lungs are failing, a procedure known as ECMO (Extracorporeal Membrane Oxygenation) can offer a lifeline. This extracorporeal system temporarily performs the work of the heart and lungs, giving them a chance to rest and recover.
ECMO supports both the heart and lungs (veno-arterial, or VA ECMO) or just the lungs (veno-venous, or VV ECMO). A surgeon inserts tubes, or cannulas, into the veins and arteries that lead directly to the heart. The blood drains through the tube into the artificial lung, which adds oxygen and removes carbon dioxide, and then pumps the oxygen-rich blood back into the body through the tube.
However, the use of ECMO is not without its risks. For instance, the veins may not work as effectively during ECMO, leading to clotting of the blood, which can occur in the veins, heart, and brain. Bleeding is another common risk, which can occur at the site of the cannula insertion and in areas such as the lungs, digestive tract, mouth and nose, brain, and abdomen.
ECMO can also impair the immune system, leaving a person more vulnerable to infections, such as pneumonia. The longer a person requires ECMO, the greater the risks of complications become, such as ventilation issues, acute kidney injury, neurological complications, skin ulcers, and malnutrition.
Despite these risks, ECMO can be a valuable tool in certain situations. For example, when a person is waiting for a lung or heart transplant and requires temporary support, ECMO can be beneficial. It can also be used during a lung or heart transplant.
The outlook for a person who requires ECMO may depend on the severity of their underlying health condition and any complications that arise during ECMO treatment. Long-term survival rates after ECMO vary widely, but data indicate that approximately 36-37% survive to hospital discharge after VA ECMO in adults. Some studies show 5-year survival around 17% after ECMO, though this is variable and depends on underlying conditions and ECMO duration.
In pediatric hematologic oncology patients, ECMO survival ranges from 34-52%, showing improvement over time and specific population success stories. For ECMO use during CPR (ECPR), in-hospital survival rates can be roughly 28.8%, significantly better than conventional CPR. Overall, adult ECMO survival rates for severe respiratory failure (including COVID-19) have been somewhat above 50% in specialized centers.
In summary, survival beyond hospital discharge ranges from about one-third to over half depending on patient selection, timing, and indication, with long-term survival (several years) less commonly reported but existent in some cohorts. Younger age, absence of cardiac arrest, and specialized center care improve prognosis. Neurologic and functional outcomes are key considerations in long-term survival data.
References:
[1] Brodie, D. L., et al. (2015). Extracorporeal membrane oxygenation for cardiogenic shock: a systematic review and meta-analysis of outcomes. Critical Care, 19(1), 624.
[2] Gattinoni, L., et al. (2020). Extracorporeal membrane oxygenation in acute respiratory distress syndrome: a systematic review and meta-analysis. Critical Care, 24(1), 1-17.
[3] Kuchera, M. (2018). Extracorporeal membrane oxygenation: a review of the indications, techniques, and outcomes. Journal of Intensive Care, 6(1), 1-11.
[4] Patterson, J. C., et al. (2018). Extracorporeal membrane oxygenation for paediatric hematologic oncology patients: a systematic review. Paediatric Anaesthesia, 28(10), 1087-1098.
[5] Rello, J., et al. (2020). Extracorporeal membrane oxygenation in acute respiratory distress syndrome: a systematic review and meta-analysis of the outcomes in COVID-19 patients. Critical Care, 24(1), 172.
- Various medical conditions, particularly those affecting the cardiovascular system and lungs, may necessitate life-saving heart procedures like ECMO.
- In emergencies, ECMO, a temporary system, takes over the functions of the heart and lungs, allowing these vital organs to rest and recover.
- This medical-health intervention, when beneficial, can support both the heart and lungs or merely the lungs, depending on the patient's condition.
- The science of medicine recognizes several risks associated with ECMO, such as blood clotting, bleeding, immune system impairment, and various complications.
- Despite these risks, the value of ECMO in certain situations, such as during transplants and emergency situations, cannot be overlooked, contributing significantly to health-and-wellness outcomes.
