Risk factors and outcome of Acinetobacter baumanii infection in severe trauma patients

To investigate incidence, risk factors and outcome of Acinetobacter baumanii infection in trauma patients. A retrospective analysis of prospectively collected data of all trauma patients admitted to a general intensive care unit (ICU) of a 1,500-bed university hospital over 3 years. Three hundred thirty trauma patients were included in the study. Thirty-six (10.9%) cases of A. baumanii infection were observed; 29 of them were late onset pneumonia. Patients with A. baumanii infection had a significantly higher Injury Severity Score (ISS) (p = 0.02), a lower Glasgow Coma Scale (GCS) on ICU admission (p = 0.03), stayed longer in the ICU (p = 0.00001), were mechanically ventilated for a longer period of time (p = 0.00001), were more frequently admitted to the emergency department with hypotension (p = 0.02), and had trans-skeletal traction for more than 3 days (p = 0.003) in comparison to the 294 patients who did not develop A. baumanii infection. At multivariate analysis the time spent on mechanical ventilation (p = 0.02) and the presence of long-term trans-skeletal traction (p = 0.04) were the only independent risk factors for A. baumanii infection. Patients with A. baumanii infection had a high mortality rate (9 out of 36; 25.0%). ISS (p = 0.003), GCS (p = 0.001) and older age (p = 0.00001), but not A. baumanii infection (p = 0.15), were independently correlated with mortality. In trauma patients prolonged mechanical ventilation and delayed fracture fixation with the persistence of trans-skeletal traction were major risk factors for A. baumanii infection. The presence of this infection was not correlated with mortality.