TY - JOUR T1 - Comparison of the Bacterial Etiology of Early-Onset Ventilator Associated Pneumonia and Late-Onset Ventilator Associated Pneumonia in Subjects Enrolled in 2 Large Clinical Studies JF - Respiratory Care DO - 10.4187/respcare.02173 SP - respcare.02173 AU - Marcos I. Restrepo AU - Janet Peterson AU - Juan F. Fernandez AU - Zhihai Qin AU - Alan C. Fisher AU - Susan C. Nicholson Y1 - 2013/01/08 UR - http://rc.rcjournal.com/content/early/2013/01/08/respcare.02173.abstract N2 - Purpose: To assess potential differences in bacterial etiology of subjects with early-onset vs. late-onset ventilator associated pneumonia (VAP). Methods: Subjects enrolled in 2004-2006 in 2 clinical studies of doripenem vs. imipenem or piperacillin/tazobactam with a diagnosis of VAP (N=500) were included in the analysis. Subjects were classified by ventilator status [early-onset VAP (<5 days of ventilation) or late-onset VAP (≥5 days of ventilation)]. Baseline demographics and bacterial etiology were analyzed by VAP status. Results: Late-onset VAP subjects had higher APACHE II scores [mean 16.6 vs. 15.5 (p=0.008)]. There were no significant differences in CPIS, gender, age, or presence of bacteremia between groups. A total of 496 subjects had a baseline pathogen and 50% of subjects in each group had ≥2 pathogens. With the exception of Staphylococcus aureus, which was common in early-onset VAP, pathogens, including potentially MDR, isolated from early vs. late-onset VAP was not significantly different between groups. Acinetobacter baumannii or Pseudomonas aeruginosa with decreased susceptibility to any study drug was observed in early and late onset VAP subjects. Conclusion: There were no significant differences in the prevalence of potential MDR pathogens associated with early or late-onset VAP, even in subjects with prior antibiotics. Clinical Implications: VAP is classified as early-onset or late-onset, in part, to identify subjects at risk for infection with resistant pathogens. Empiric therapy for early-onset VAP should also include agents likely to be effective for potential MDR pathogens. Further prospective studies should evaluate microbiology trends in subjects with VAP. ER -