Differences in Early- and Late-Onset Ventilator-Associated Pneumonia Between Surgical and Trauma Patients in a Combined Surgical or Trauma Intensive Care Unit

Abstract
Ventilator-associated pneumonia (VAP) is a leading cause of morbidity in the perioperative period. Based on differences in causes, VAP has been divided into early (≤96 hours of admission) and late (>96 hours of admission) onset. We sought to compare differences in patient characteristics and outcome between early- and late-onset VAP in trauma and nontrauma surgical patients. A retrospective analysis of prospectively collected data were performed for all surgical and trauma patients admitted to the surgical or trauma intensive care unit of an academic medical center from December 1996 to March 2005 who developed VAP. Patients with early- and late-onset VAP were compared with regard to patient characteristics, cause, and outcome using bivariate and multivariate analyses. Three hundred thirty VAPs were identified in 233 trauma (71%) and 97 nontrauma surgery patients (29%). There was no statistically significant difference in recurrence, mortality, or length of stay between early- and late-onset VAP in trauma patients. Mortality for late- onset VAPs in nontrauma patients was 44% versus 23% for early-onset VAPs (p = 0.09). On a per case basis, trauma patients had significantly better mortality (11% vs. 41%) and length of stay (33.1 ± 1.4 vs. 55.8 ± 4.1 days) than nontrauma surgical patients with VAP (p < 0.0001), although the rate of VAP-related death favored the nontrauma patients (1.8 deaths of 100 intensive care unit trauma admissions vs. 1.1 deaths of 100 intensive care unit nontrauma admissions, p = 0.05). Although there is a trend toward worse outcome in nontrauma patients with late-onset VAP, trauma patients with late- and early-onset VAP behave similarly. On a per case basis, trauma patients have significantly better outcomes than nontrauma surgical patients with VAP when cared for within the same surgical or trauma intensive care unit.