Acinetobacter baumannii ventilator-associated pneumonia: epidemiology, clinical characteristics, and prognosis factors

Abstract

The aim of this study was to describe the epidemiological characteristics of Acinetobacter baumannii ventilator-associated pneumonia (VAP) and to identify factors predictive of a poor outcome. A retrospective study was conducted over 16 months in a Tunisian intensive care unit (ICU). All adult patients with A. baumannii VAP were included. Ninety-two patients were included in they study; 41 (44.6%) were admitted because of multiple trauma. The mean age of the patients was 44.5±19.5 years. All patients needed mechanical ventilation on admission. The mean SAPS II score was 39±15. The mean delay before VAP onset was 8.1±4.7 days. On VAP onset, 57 patients (62%) developed septic shock. Only 14.2% of isolated strains were susceptible to imipenem; none were resistant to colistin. The mean duration of mechanical ventilation was 20±11 days. The mean duration of ICU stay was 24.3±18.7 days. ICU mortality was 60.9%. In the multivariate analysis, factors predictive of a poor outcome were previously known hypertension (odds ratio 5.8, 95% confidence interval 1.4-24.9; p=0.018) and VAP-related septic shock (odds ratio 8.5, 95% confidence interval 3-23.7; p<0.001). A. baumannii VAP is associated with a high mortality. Hemodynamic impairment is predictive of a poor outcome.