Background: The use of extracorporeal membrane oxygenation (ECMO) in the trauma population has been reported to have a mortality benefit in patients with severe refractory hypoxic respiratory failure. This study compares the early initiation of ECMO for the management of severe adult respiratory distress syndrome (ARDS) versus a historical control immediately preceding the use of ECMO for trauma patients.
Methods: A retrospective study was conducted at a single verified Level I trauma center. The study population was limited to trauma patients diagnosed with severe ARDS using the Berlin definition (PaO2/FIO2 ratio < 100). Patients managed with ECMO versus conventional ventilation (CONV) were compared. The primary outcome of interest was mortality; secondary outcomes included hospital length of stay, intensive care unit-free days, and ventilator-free days.
Results: Fifteen ECMO patients managed from March 2013 to November 2014 were identified, as were 14 CONV patients managed from March 2012 to February 2013 who met the Berlin definition of severe ARDS. Data related to age, Injury Severity Scores (ISSs), admission lactic acid levels, base deficit, the number of transfused red blood cell units within the first 24 hours, and presence of severe traumatic brain injury were collected and were not statistically different between the groups. Likewise, Murray Lung Injury (MLI), Sequential Organ Failure Assessment (SOFA), and Acute Physiology and Chronic Health Evaluation II (APACHE II) scores determined at the onset of severe ARDS were not statistically different between the groups. Median hospital stay (CONV, 28.0 days [14.0-47.0]; ECMO, 43.5 days [30.0-93.0]; p = 0.15), intensive care unit-free days (CONV, 0.0 days [0.0-5.0]; ECMO, 5.0 days [0.0-7.0]; p = 0.26), and ventilator-free days (CONV, 0.0 days [0.0-10.0]; ECMO, 8.0 days [0.0-19.0]; p = 0.13) were not statistically different between the groups. Mortality in the ECMO group was significantly reduced compared with the CONV group (ECMO, 13.3%; CONV, 64%; p = 0.01). Timing from the onset of severe ARDS to ECMO intervention occurred at a mean 1.9 ± 1.4 days.
Conclusion: Patients who were treated with ECMO for severe ARDS had an improved mortality compared with historical controls. ECMO should be considered at the early onset of severe ARDS to improve survival.
Level of evidence: Therapeutic study, level IV.