Determining Extracorporeal Membrane Oxygenation Outcomes in Obese Patients with ARDS

Abstract

Extracorporeal membrane oxygenation (ECMO) is crucial for managing acute respiratory distress syndrome (ARDS) refractory to conventional therapy, but its impact on obese ARDS patients remains inadequately understood due to relative contraindications per the Extracorporeal Life Support Organization (ELSO) guidelines. This study aimed to analyze the association between obesity and ECMO outcomes in ARDS patients. Using five years of National Inpatient Sample data (2016–2020), we identified ARDS patients through ICD-10 codes, classifying those with a BMI > 30 as obese. Univariate and multivariate analyses were performed to assess mortality, rates of left ventricular assist devices, and tracheostomy differences between obese and non-obese patients, with secondary outcomes examining the impact of obesity on length of stay (LOS) and total hospitalization charges (TOTCHG). Among 3,219 ARDS patients requiring ECMO, 8.2% were obese. While initial univariate analysis showed a non-significant 43% lower mortality odd in obese patients, adjusting for confounders revealed a statistically significant 46% lower odd of mortality compared to non-obese patients (adjusted odds ratio 0.54, 95% confidence interval 0.3-0.94, p 0.032). LOS and TOTCHG did not significantly differ between the two groups, nor did the rates of LVAD or tracheostomy. These findings suggest that obesity may confer a survival advantage in ARDS patients undergoing ECMO, potentially due to factors such as nutritional reserves and the obesity paradox observed in critical illnesses. Therefore, BMI alone should not preclude obese patients from ECMO treatment, emphasizing the need for further research to inform clinical decision-making in this population.