(1367) Mortality in Patients Admitted With COVID-19 vs Pneumonia Who Underwent ECMO Using NIS, 2016-2020

Introduction: Extracorporeal Membrane Oxygenation (ECMO) is an established treatment modality for severe Acute Respiratory Distress Syndrome (ARDS), and was quickly adopted during the pandemic for support of patients with severe COVID-19 who developed ARDS. The aim of this study is to compare mortality rates between patients requiring ECMO prior to COVID-19 and during the first year of the COVID-19 pandemic.

Methods: This is a retrospective study using the National Inpatient Sample (NIS) Database from the years 2016 to 2020. We included patients aged 18 years or older who were admitted with COVID-19 or Pneumonia and underwent ECMO. The cohort was categorized into patients with COVID-19 and ECMO vs patients with Pneumonia and ECMO. The baseline characteristics were compared between the two groups. The primary outcome of the study was inpatient mortality. Multivariate logistic regression analysis was performed to analyze predictors and risks of mortality in patients with and without COVID-19 who underwent ECMO.

Results: A total of 4 429 217 cases were analyzed, of which 3875 underwent ECMO. Among the non-COVID group, ECMO was used in 1835 patients, of whom 35% died (CI 30.2%-40.3%, p=0.025), and among COVID patients, ECMO was used in 2040 patients, of whom 49.3% died (CI 44.1-54.4%, p=0.026).
Among patients admitted with pneumonia, and after adjusting for covariates, use of ECMO was associated with significant higher odds of mortality (OR 17.1, CI 12.0 to 24.5, p< 0.001), as well as cardiogenic shock (OR 16.6, CI 15.1 to 18.2, p< 0.001) and hypovolemic shock (OR 7.54, CI 6.24 to 9.12, p< 0.001). History of Heart Failure was also associated with higher odds of mortality (OR 1.21, CI 1.17-1.25, p< 0.001) and asthma with a lower risk of mortality (OR 0.51, CI 0.48-0.54, p< 0.001).
Among patients admitted with COVID-19, after adjusting for covariates, use of ECMO was associated with a higher risk of mortality (OR 15.4, CI 12.0-19.8, p< 0.001), as well as Cardiogenic and Hypovolemic Shock, but in contrast with non-COVID patients, Obesity (OR 1.22, CI 1.18-1.27, p< 0.001) and ESRD (OR 1.29, CI 1.20 to 1.39, p< 0.001) were associated with a higher risk of mortality.

Conclusions: Use of ECMO has a higher mortality rate in patients admitted with COVID (49.3%) vs patients admitted with Pneumonia (35%).