Antibiotic prescription for community-acquired pneumonia in the intensive care unit: impact of adherence to Infectious Diseases Society of America guidelines on survival.

BACKGROUND: The purpose of our study was to analyze prognostic factors associated with mortality for patients with severe community-acquired pneumonia (CAP). METHODS: We conducted a prospective multicenter study including all patients with CAP admitted to the intensive care unit during a 15-month period in 33 Spanish hospitals. Admission data and data on the evolution of the disease were recorded. Multivariate analysis was performed using the SPSS statistical package (SPSS). RESULTS: A total of 529 patients with severe CAP were enrolled; the mean age (+/-SD) was 59.9+/-16.1 years, and the mean Acute Physiology and Chronic Health Evaluation (APACHE) II score (+/-SD) was 18.9+/-7.4. Overall mortality among patients in the intensive case unit was 27.9% (148 patients). The rate of adherence to Infectious Diseases Society of America (IDSA) guidelines was 57.8%. Significantly higher mortality was documented among patients with nonadherence to treatment (33.2% vs. 24.2%). Multivariate analysis identified age (odds ratio [OR], 1.7), APACHE II score (OR, 4.1), nonadherence to IDSA guidelines (OR, 1.6), and immunocompromise (OR, 1.9) as the variables present at admission to the intensive care unit that were independently associated with death in the intensive care unit. In 15 (75%) of 20 cases of Pseudomonas aeruginosa infection, the antimicrobial treatment at admission was inadequate (including 8 of 15 cases involving patients with adherence to IDSA guidelines). Chronic obstructive pulmonary disease (OR, 17.9), malignancy (OR, 11.0), previous antibiotic exposure (OR, 6.2), and radiographic findings demonstrating rapid spread of disease (OR, 3.9) were associated with P. aeruginosa pneumonia. CONCLUSIONS: Better adherence to IDSA guidelines would help to improve survival among patients with severe CAP. Pseudomonas coverage should be considered for patients with chronic obstructive pulmonary disease, malignancy, or recent antibiotic exposure.