Acute respiratory distress syndrome after bacteremic sepsis does not increase mortality

To determine whether acute respiratory distress syndrome (ARDS) complicating bacteremic sepsis independently affects mortality in critically ill patients, we conducted a 3-year retrospective cohort study in a surgical intensive care unit. We included all consecutive patients with blood culture-positive sepsis and measured organ dysfunctions and mortality. Among 4,530 admissions, 196 cases of bacteremic sepsis were recorded. ARDS occurred in 31 (16%) of these patients. The case fatality rate was 58% in patients with ARDS compared with 31% in patients without ARDS. Using Cox proportional hazards regression with time-dependent variables, the unadjusted hazard ratio for death was 1.8 (95% confidence interval [CI], 1.0-3.2). After adjusting for comorbid factors that were present before the onset of sepsis, the hazard ratio was 2.2 (95% CI, 1.2-3.9). After further adjustment was made for nonpulmonary organ dysfunctions and microbiologic factors that were independently associated with mortality, the adjusted hazard ratio for ARDS was 0.6 (95% CI, 0.3-1.2). Among critically ill surgical patients, ARDS complicating bacteremic sepsis remains common, but it is not independently associated with short-term mortality, after adjusting for severity of illness and nonpulmonary organ dysfunctions evolving after the onset of sepsis.