Acute respiratory distress syndrome among trauma patients: trends in ICU mortality, risk factors, complications and resource utilization

To evaluate trends in mortality and related factors among trauma patients who developed acute respiratory distress syndrome (ARDS). Observational study based on data prospectively gathered in computerized trauma registry. Trauma intensive care unit (ICU) of 48 beds in level I trauma center. All trauma patients with ARDS admitted during 1985-87 (486, group 1 [G1]) and 1993-95 (552, group 2[G2]). ARDS was defined by American-European Consensus Conference criteria and the need for 48 h or more on mechanical ventilation with FIO2 greater than 0.50 and PEEP of more than 5 cmH2O. Demographics, severity score, injury-admission delay time, first 24-h transfusion and septic and organ system failure complications were independent variables. ICU mortality was the dependent variable. ICU length of stay (LOS) and life support techniques were considered. Respiratory and renal support strategies were different in the two time periods. Mortality decreased over the period (G1: 29.2% vs G2: 21.4%, p < 0.04), in patients aged both over and under 65 years. Multivariate analysis showed mortality was related to age, severity and time period (G1 1.68-fold that in G2) and that the greater G1 mortality was related to more renal failure and hematologic failure/dysfunction. ICU LOS decreased from 31.7+/-26.7 days (G1) to 27.3+/-22 days (G2) (p < 0.003). Mortality among trauma patients with ARDS declined over the 8 years studied and was associated with less organ failure. This reduction was probably the result of new approaches to mechanical ventilation, renal failure replacement and vasoactive drug therapy.