Ventilators have gotten a lot of attention in the ongoing fight against COVID-19. But hundreds of hospitals around the world have another, less-publicized weapon that might help some of the most desperately ill patients survive when ventilators aren’t enough.

Right now, hundreds of COVID-19 patients in intensive care worldwide are being kept alive using ECMO life-support technology and the skills of specially trained teams of nurses, respiratory therapists, technicians, and physicians. Meanwhile, experts are tracking in real time how well ECMO works in treating COVID-19. But early indications are that it could offer a last chance at life for a subset of the sickest COVID-19 patients: Those who were relatively young and healthy before becoming infected with the novel coronavirus.

Early evidence, based on a rapidly evolving international registry, shows that more than a third of critically ill COVID-19 patients who have completed ECMO treatment survived and left the hospital alive. Without ECMO, most would probably have died.

With more time and data, it will be possible to see if ECMO saves as many people as it did during the H1N1 flu pandemic of 2009, when 60% of the patients critically ill enough to need ECMO were able to survive the viral infection.

Replacement for Heart and Lungs

Short for extracorporeal membrane oxygenation, ECMO involves a complex circuit of pumps, tubes, filters, and monitors that must be operated by an expert team, to take over for both the heart and lungs. It channels the patient’s blood outside their body in order to add oxygen and remove waste before propelling it back to into the circulation system.

Major medical centers, including the University of Michigan’s Michigan Medicine, have used ECMO for decades as a last-chance treatment for patients ranging from infants with heart malformations to adults with lung failure. Robert Bartlett, MD, now an active emeritus professor of surgery at U-M, led the development of modern ECMO starting in the early 1980s, and has become known worldwide as the “grandfather of ECMO.” 

Now, ECMO is being used in certain COVID-19 patients. But experts caution that patients must get evaluated by an ECMO center and transferred before their condition worsens too much. They should not have been on a ventilator more than seven days before starting ECMO, which means that they should be considered for ECMO soon after the decision to intubate them is made.

Seven of the eight patients on ECMO at Michigan Medicine as of mid-April were COVID-19 patients, and most had transferred from hospitals in Detroit and its suburbs.

“Despite the substantial resources required to care for patients on ECMO, we believe this is an appropriate strategy for selected patients that are otherwise at imminent risk of death,” says Jonathan Haft, MD, medical director of U-M’s ECMO program. He adds that so far, the outcomes for ECMO patients treated by U-M’s team appear to be similar to outcomes from treating patients with other causes of acute respiratory failure.  

International Cooperation

Through a massive and rapid effort by staff, ELSO has built a real-time dashboard of data on patients placed on ECMO for COVID-19 since March. As of April 21, it shows that more than 470 patients with suspected or confirmed cases of COVID-19 have been treated at the ECMO centers that are sharing their data. Most were men in their 40s and early 50s. Nearly half had obesity and one-fifth had diabetes.

In March, Bartlett and his colleagues created guidance for the use of the treatment in COVID-19, to help centers with existing ECMO capability understand when to devote resources to providing this level of care, and which patients to prioritize. They do not recommend that hospitals set up a new ECMO program in the middle of a pandemic. “If a patient is on a ventilator, and failing to respond, and they are relatively young with few comorbidities, that’s the time to think about ECMO,” says Bartlett.

Sharing real-time data from ECMO centers around the world has been brought emerging data to frontline providers searching for information on ECMO and COVID-19, says Ryan Barbaro, MD, MS, the U-M pediatric intensivist who leads the ELSO Registry program.

“We don’t know yet what the survival rate will be for ECMO-supported patients with this virus, but,” he says. “Sharing what we do know as the information is accumulated has been a valued resource for those considering ECMO support in patients with COVID-19.”