Predictors of mortality in trauma patients with acute respiratory distress syndrome receiving extracorporeal membrane oxygenation.

Objective: Trauma-related Acute Respiratory Distress Syndrome (TR-ARDS) mortality ranges from 30 to 80%. Extracorporeal membrane oxygenation (ECMO) has demonstrated a survival benefit in select cases of TR-ARDS. In order to provide improved patient selection, we evaluated predictors of mortality in TR-ARDS patients receiving ECMO, hypothesizing age and severe thoracic trauma as risk factors for mortality.

Methods: The Trauma Quality Improvement Program (2010-2016) was queried for patients ≥ 18-years-old with TR-ARDS receiving ECMO. Survivors were compared to those who died. A multivariable logistic regression model was used for analysis and included covariates known to increase risk of mortality in trauma patients.

Results: From 362 TR-ARDS patients on ECMO, 226 (62.4%) survived and 136 (37.6%) died. Those who died were older (median, 28 vs. 24-years-old,  = 0.036) and had a higher injury severity score (29 vs. 26,  = 0.040) than survivors. After adjusting for covariates, independent predictors of mortality included a severe head (OR=2.66, CI=1.29-5.49,  = 0.008) and thorax (OR =3.52, CI=1.96-6.33,  < 0.001) injury. Age ≥ 65-years-old was not a predictor of mortality ( = 0.432).

Discussion: Age ≥ 65 years did not appear to increase the risk of mortality in patients with TR-ARDS receiving ECMO. However, those with severe head or thorax injury had more than a two-fold and three-fold increased risk of death, respectively. TR-ARDS patients differ from medical ARDS patients in terms of etiology, age and injuries. Thus, prior pre-ECMO mortality prediction models may lack predictive capability for trauma patients. Future prospective studies are needed to confirm our findings and develop guidelines for utilization of ECMO for trauma patients.