How ECMO Is Redefining Death

🌈 Abstract

The article discusses the use of extracorporeal membrane oxygenation (ECMO) technology, which can perform the work of the heart and lungs outside the body. It explores the ethical dilemmas and complexities that arise as ECMO becomes more widely used, particularly in end-of-life situations where patients are kept alive indefinitely on the machine with no hope of recovery. The article also examines how ECMO is transforming medical care, saving lives in new ways, and how researchers are working to make the technology more portable and accessible.

🙋 Q&A

[01] The Beginnings of ECMO

1. What inspired the initial development of ECMO technology?

• The idea for ECMO was first conceived by John Gibbon in 1931 when he cared for a woman with a pulmonary embolism and realized that if he could remove and oxygenate her blood outside her body, he might have been able to save her life.
• Gibbon went on to develop the first machine that could support the circulation of a cat for 30 minutes, and in 1952 used it to replace the heart and lungs of a college student during an operation, marking the advent of modern open-heart surgery.

2. How did Robert Bartlett's work improve upon Gibbon's initial ECMO design?

• In 1965, Bartlett built a "membrane oxygenator" out of silicone, which allowed oxygen to diffuse slowly into the blood across a semipermeable membrane, mitigating the toxic effects of the direct mixing of oxygen and blood in Gibbon's original design.
• Bartlett's devices were able to keep animals alive through "extracorporeal circulation" for up to 4 days, and in 1971 his colleagues used a similar setup to support the first human survivor of ECMO.

3. How did the use of ECMO evolve over time?

• In the 1970s, ECMO became standard in the largest pediatric centers, with a survival rate of 80% for newborns with respiratory failure.
• However, a trial with adult patients in 1979 found a mortality rate of 90%, and the adoption of ECMO for adults largely stalled until the H1N1 influenza epidemic in 2008, when ECMO was found to improve outcomes.
• The number of hospitals offering ECMO increased threefold within 10 years, and then the COVID-19 pandemic further drove the widespread adoption of the technology.

[02] ECMO and the COVID-19 Pandemic

1. How did ECMO help improve outcomes for COVID-19 patients compared to ventilators?

• Early in the pandemic, physicians at NYU treated 30 ventilated COVID patients with ECMO, and 90% survived, compared to a mortality rate as high as 60% for ventilated COVID patients.
• A 2020 study found a 60% survival rate among over 1,000 COVID patients treated with ECMO.
• At Vanderbilt University, 35 ventilated COVID patients were approved for ECMO, and 20 survived, while the survival rate among the rest was only 10%.

2. What advantages did using ECMO without a ventilator first provide?

• Intensivist Jeffrey DellaVolpe found that the survival rate was 75% among COVID patients treated with ECMO first, without going on a ventilator, compared to around 50% for ventilated patients on ECMO.
• One reason was that ECMO-first patients could remain awake and work with physical therapists, as ECMO does not require sedation like ventilators.

3. How did ECMO transform the care of COVID-19 patients in the ICU?

• ECMO allowed some COVID patients to be awake, walking, and engaging in activities while their lungs healed, rather than being sedated and on a ventilator.
• This transformed the typically hushed and sepulchral ICU environment, with the potential for ICUs to become "full of walking, talking patients" on ECMO.

[03] Expanding the Use of ECMO

1. How is ECMO being used to treat cardiac arrest patients?

• Emergency physician Jon Marinaro is using ECMO to treat cardiac arrest patients, as it can take over the work of the heart until it is restarted.
• In a randomized study, 43% of cardiac arrest patients treated with ECMO and CPR survived, compared to only 6% with CPR alone.
• Marinaro has been able to save patients who received over an hour of CPR with no improvement, which would normally be considered unsurvivable.

2. What challenges does the expanded use of ECMO present?

• ECMO can keep patients alive indefinitely, even when there is no hope of recovery, leading to ethical dilemmas about when to discontinue treatment.
• There are concerns that ECMO may become an expected default treatment, like CPR, even in cases where the chances of survival are low.
• The high cost of ECMO, with median charges of $870,000 for COVID patients, raises questions about resource allocation.

[04] Ethical Dilemmas Surrounding ECMO

1. What ethical issues arise when ECMO keeps patients alive with no hope of recovery?

• ECMO can keep patients alive and conscious in a "precarious form of existence" with no prospect of long-term survival, raising questions about traditional definitions of life and death.
• Decisions about when to discontinue ECMO treatment involve delivering a "death sentence" and can create profound ethical dilemmas for medical teams.

2. How do patient expectations and legal considerations complicate ECMO decisions?

• There is a concern that patients may come to expect ECMO as a default treatment, leading to its overuse even in cases where recovery is unlikely.
• Lawsuits, such as a $10 million award against doctors for not offering ECMO, can pressure medical teams to provide the technology even when the prognosis is poor.

3. How are researchers working to address the ethical challenges of ECMO?

• Bartlett's lab is exploring ways to get ECMO patients out of the ICU and even home, to avoid indefinite confinement.
• Innovations like a wearable "mini-ECMO" and ECMO devices that secrete nitric oxide to prevent clotting could make the technology more portable and accessible.
• Applying ECMO to organ transplantation could also transform the field, potentially eliminating wait lists and allowing more organs to be utilized.