Impact of adverse events on outcomes in intensive care unit patients*

OBJECTIVE: To examine the association between predefined adverse events (AE) (including nosocomial infections) and intensive care unit (ICU) mortality, controlling for multiple adverse events in the same patient and confounding variables. DESIGN: Prospective observational cohort study of the French OUTCOMEREA multicenter database. SETTING: Twelve medical or surgical ICUs. PATIENTS: Unselected patients hospitalized for > or = 48 hrs enrolled between 1997 and 2003. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Of the 3,611 patients included, 1415 (39.2%) experienced one or more AEs and 821 (22.7%) had two or more AEs. Mean number of AEs per patient was 2.8 (range, 1-26). Six AEs were associated with death: primary or catheter-related bloodstream infection (BSI) (odds ratio OR, 2.92; 95% confidence interval CI, 1.6-5.32), BSI from other sources (OR, 5.7; 95% CI, 2.66-12.05), nonbacteremic pneumonia (OR, 1.69; 95% CI, 1.17-2.44), deep and organ/space surgical site infection without BSI (OR, 3; 95% CI, 1.3-6.8), pneumothorax (OR, 3.1; 95% CI, 1.5-6.3), and gastrointestinal bleeding (OR, 2.6; 95% CI, 1.4-4.9). The results were not changed when the analysis was confined to patients with mechanical ventilation on day 1, intermediate severity of illness (Simplified Acute Physiology Score II between 35 and 55), no treatment-limitation decisions, or no cardiac arrest in the ICU. CONCLUSIONS: AEs were common and often occurred in combination in individual patients. Several AEs independently contributed to death. Creating a safe ICU environment is a challenging task that deserves careful attention from ICU physicians.