COVID-19 patients treated with extracorporeal membrane oxygenation (ECMO) appear to have a much lower mortality rate than initial early reports suggested.

ECMO has been utilized in COVID-19 patients with acute respiratory distress syndrome (ARDS) and hypoxemia that fails to respond to standard treatment. But early case series suggested a high mortality rate—topping 90 percent.

In Annals of Surgery, researchers report the largest U.S. study to date evaluating outcomes of 1,182 COVID-19 patients with ARDS who received ECMO therapy at 155 U.S. academic medical centers and their affiliates between April and September 2020.

Most patients were age 50 or younger (58 percent), 37 percent were 51 to 64 years-old, and about 5 percent were 65 years or older; 71 percent were male and race/ethnicity was mixed, including 32 percent Caucasian, 22 percent Black, 5 percent Asian, 38 percent Hispanic and 41 percent unknown/other.

The in-hospital mortality rate was 45.9 percent, far lower than initial early reports and refuting previous reports of futility for ECMO in COVID-19 patients with ARDS, report Dr. Ninh T. Nguyen of the University of California, Irvine Medical Center and colleagues.

The in-hospital mortality rate increased with age, from 25.2 percent for those in the youngest age group (1 to 30 years), to 42.2 percent for those 31 to 50 years; 53.2 percent for the 51- to 64-year-olds; and 73.7 percent for those aged 65 and older.

Analysis of a subset of COVID-19 patients with ARDS managed with versus without ECMO showed relatively high in-hospital mortality for both groups (44.6 percent with ECMO and 37.9 percent without ECMO, P<0.01).

“This likely represents the efficacy of ECMO as a salvage therapy which is applied to patients who have failed conventional ventilatory support,” the authors say.

Overall, they say their data showing greater than 50 percent survival “supports the provision in the use of ECMO for COVID-19-related ARDS.”

Their comparative analysis also demonstrated that the use of ECMO therapy significantly increased the length of stay as well as hospitalization cost “and therefore selection for ECMO therapy should be taken within the context of available institutional resources,” they advise.

They call for further research to determine which subsets of patients with COVID-19 would benefit the most from ECMO therapy.

The study had no specific funding. Dr. Nguyen has served as a speaker for Olympus and Endogastric Solutions.