Ventilator-associated pneumonia in extremely preterm neonates in a neonatal intensive care unit: characteristics, risk factors, and outcomes

Abstract

Objective: To determine the rates, characteristics, risk factors, and outcomes of ventilator-associated pneumonia (VAP) in extremely preterm neonates in a neonatal intensive care unit (NICU).

Methods: A prospective cohort study was conducted at the St Louis Children's Hospital on all patients who had birth weight <or=2000 g and were admitted to the NICU for >or=48 hours from October 2000 to July 2001. Extremely preterm neonates were defined as neonates with estimated gestational age (EGA) <28 weeks. The primary outcome was the development of VAP. Secondary outcomes were death and NICU length of stay (LOS). Multiple logistic regression was performed to determine independent predictors for VAP and mortality.

Results: A total of 229 patients were enrolled. Sixty-seven (29%) had EGA <28 weeks. Nineteen episodes of VAP occurred in 19 (28.3%) of 67 mechanically ventilated patients. VAP rates were 6.5 per 1000 ventilator days for patients with EGA <28 weeks and 4 per 1000 ventilator days for EGA >or=28 weeks. By multivariate analysis, bloodstream infection before VAP (adjusted odds ratio: 3.5; 95% confidence interval [CI]: 1.2-10.8) was an independent risk factor for VAP after adjustment for the duration of endotracheal intubation. Ventilator-associated pneumonia (adjusted odds ratio: 3.4; 95% CI: 1.2-12.3) was an independent predictor of mortality. A strong association between VAP and mortality was observed in neonates who stayed in the NICU >30 days (relative risk: 8.0; 95% CI: 1.9-35.0). Patients with VAP also had prolonged NICU LOS (median: 138 vs 82 days).

Conclusions: VAP occurred at high rates in extremely preterm neonates and was associated with increased mortality. Additional studies are needed to develop interventions to prevent VAP in NICU patients.