Facial mask noninvasive mechanical ventilation reduces the incidence of nosocomial pneumonia - A prospective epidemiological survey from a single ICU

Objective: To evaluate the impact of noninvasive positive pressure mechanical ventilation (NPPV) on ventilator-associated pneumonia (VAP). Design: Prospective observational study, Setting: Medical intensive care unit (ICU) of a university teaching hospital. Patients: Cohort of 320 consecutive patients staying in the ICU more than 2 days and mechanically ventilated for greater than or equal to 1 day, Measurements and results: VAP was diagnosed when, satisfying classical clinical and radiological criteria, fiberoptic bronchoalveolar lavage and/or protected specimen brush grew greater than or equal to 10(4) and greater than or equal to 10(3) CFU/ml, respectively, of at least one microorganism. Patients were classified into four subgroups according to the way in which mechanical ventilation was delivered: NPPV then tracheal intubation (TI) (n = 38), TI then NPPV (N = 23), TI only (n = 199), and NPPV only (n = 60), Occurrence of VAP was estimated by incidence rate and density of incidence, Risk factors for VAP were assessed by logistic regression analysis, Twenty-seven patients had 25 episodes of VAP. The incidence rates for patients with VAP were 18 % In NPPV-TI, 22 % in TI-NPPV, 8 % in TI, and 0 % in NPPV (p < 0.0001), The density of incidence: of VAP was 0.85 per 100 days of TI and 0.16 per 100 days of NPPV (p = 0.04). Logistic regression showed that length of ICU stay and ventilatory support were associated with VAP, Conclusions: There is a significantly lower incidence of VAP associated with NPPV compared ro tracheal intubation, This is mainly explained by differences in patient severity and risk exposure.