Rates and Pathogens Causing Hospital-Associated Respiratory Infections in a Regional Burn Center, 2008-2012
Background: Burn injuries are a common source of morbidity and mortality in the United States, but limited data exist on burn infections. Although the National Burn Repository reports pneumonia as the most frequent clinically related complication among acute burn admissions, no standard definition for pneumonia has been used. Inhalation injury and prolonged mechanical ventilation place burn patients at extremely high risk for hospital-associated respiratory infections (HARI). This study measured rates and pathogens causing HARI in a large regional burn center.
Methods: The University of North Carolina Hospitals is an 806-bed tertiary care facility that includes a 21-bed ICU for severely ill patients with burns and extensive exfoliating skin conditions. Comprehensive hospital-wide surveillance for HARI was collected over a 5 year period (2008-2012) in accordance with CDC/NHSN criteria. Incidence of ventilator-associated pneumonia (VAP) was calculated as infections per 1000 ventilator-days. Incidence of tracheobronchitis was calculated as infections per 1000 patient-days. Methicillin-resistant S. aureus and Gram-negative bacilli susceptible to ≤1 class of clinically relevant antibiotics were considered multidrug-resistant (MDR).
Results: The burn ICU VAP rates ranged from 2.78 to 5.55 per 1000 ventilator-days compared to 1.57 to 4.53 in all other ICUs. While a trend towards decreased VAP rates was noted in both populations over time, the burn ICU had higher VAP rates than all other ICUs (Figure 1). Burn ICU tracheobronchitis rates ranged from 0.95 to 2.14 infections per 1000 patient-days with little difference in rates over time or between the burn ICU and all other ICUs (Figure 2). In the burn ICU, 146 organisms were isolated from 119 HARI (1.23 pathogens/infection), with 30% classified as MDR. The most common pathogens were P. aeruginosa, enteric Gram-negative bacilli, S. aureus, S. maltophilia, and Acinetobacter spp. (Figure 3). A MDR Acinetobacter outbreak occurred in 2008 in the burn ICU.
Conclusion: HARI remains a major problem in the burn ICU with a high prevalence of MDR organisms. Continued surveillance and research is necessary to optimize prevention and treatment of these infections in burn patients.
D. Van Duin, None
S. Jones, None
B. Cairns, None
W. Rutala, None
D. J. Weber, None