Background: To determine risk and prognostic factors in patients admitted to the intensive care unit (ICU) in which an episode of bacteremia caused by Pseudomonas aeruginosa has been diagnosed.
Patients and method: Cohort, observational, prospective, multicenter study. Patients admitted to 30 ICUs in Spain in whom one or more pathogens were isolated from blood cultures were included.
Results: In a total of 16,216 patients admitted to the participating ICUs during the study period, 949 episodes of bacteremia were diagnosed In 77 cases (8.11%), P. aeruginosa was the causative pathogen, with an infection rate of 4.7 episodes per 1000 patients. Independent risk factors associated with P. aeruginosa bacteremia were as follows: respiratory infection focus (OR 3.92; 95% IC 2.33-6.59; p </= 0.0001), previous use of antibiotics (OR 2.13; 95% IC 1.18-3.81; p </= 0.0078), arterial catheter (OR 4.09; 95% IC 2.26-7.38; p </= 0.0001), and previous longer ICU stay (days) (OR 1.02; 95% IC 1.003-1.033; p = 0.0274). Crude mortality rate in patients with bacteremia caused by P. aeruginosa was 50.6% (39/77), whereas mortality rate of bacteremia caused by other pathogens was 38.6% (337/872) (p = 0.039). This difference was also found for attributed mortality (31.2% [24/77] vs. 20.4% [178/872], (p = 0.027). In the multivariate analysis adjusted by respiratory infection focus, previous ICU stay, and age, crude mortality (OR 1.55; 95% CI 0.96-2.51; p = 0.071) and attributed mortality (OR 1.63; 95% CI 0.96-2.78; p = 0.0709) of P. aeruginosa bacteremia were higher than in bacteremia caused by other pathogens. In the multivariate analysis, risk factors significantly associated with crude mortality were respiratory infection focus (OR 4.13; 95% IC 1.15-14.76; p = 0.0293) and severe sepsis or septic shock (OR 4.96; 95% IC 1.23-20.09; p = 0.0248).
Conclusions: Bacteremia caused by P. aeruginosa admitted to the ICU have a higher crude and attributed mortality than bacteremias caused by other pathogens. Prognosis is associated with the presence of severe sepsis or septic shock and respiratory infection focus.