Incidence of acute respiratory distress syndrome and associated mortality in a polytrauma population

Abstract

BackgroundThe incidence of acute respiratory distress syndrome (ARDS) has decreased in the last decade by improvement in trauma and critical care. However, it still remains a major cause of morbidity and mortality. This study investigated the current incidence and mortality of ARDS in polytrauma patients.MethodsA 4.5-year prospective study included consecutive trauma patients admitted to a level 1 trauma center intensive care unit (ICU). Isolated head injuries, drowning, asphyxiation, burns, and deaths <48 hours were excluded. Demographics, Injury Severity Score (ISS), physiologic parameters, resuscitation parameters, Denver Multiple Organ Failure scores, and ARDS data according to Berlin criteria were prospectively collected. Data are presented as median (IQR), and p<0.05 was considered significant.Results241 patients were included. The median age was 45 (27–59) years, 178 (74%) were male, the ISS was 29 (22–36), and 232 (96%) patients had blunt injuries. Thirty-one patients (13%) died. Fifteen patients (6%) developed ARDS. The median time to ARDS onset was 3 (2–5) days after injury. The median duration of ARDS was 2.5 (1–3.5) days. All patients with ARDS were male compared with 61% of non-ARDS patients (p=0.003). Patients who developed ARDS had higher ISS (30 vs. 25, p=0.01), lower Partial Pressure of Oxygen in arterial blood (PaO2) both in the emergency department and ICU, and higher Partial Pressure of Carbon Dioxide in arterial blood (PaCo2) in the ICU. Patients with ARDS needed more crystalloids <24 hours (8.7 vs. 6.8 L, p=0.03), received more fresh frozen plasma <24 hours (3 vs. 0 U, p=0.04), and more platelet <8 hours and <24 hours. Further, they stayed longer on the ventilator (11 vs. 2 days, p<0.001), longer in the ICU (12 vs. 3 days, p<0.001), and in the hospital (33 vs. 15 days, p=0.004). Patients with ARDS developed more often multiple organ dysfunction syndrome (40% vs. 3%, p<0.001) and died more often (20% vs. 3%, p=0.01). Only one patient with ARDS (7%) died of ARDS.DiscussionIn this polytrauma population mortality was predominantly caused by brain injury. The incidence of ARDS was low; its presentation was only early onset, during a short time period, and accompanied by low mortality.Level of evidenceLevel III.