Epidemiological and microbiological analysis of ventilator-associated pneumonia patients in a public teaching hospital

ABSTRACT

Ventilator-associated pneumonia (VAP) is the most commonly-acquired infection in patients in intensive care units. We analyzed epidemiological and microbiological characteristics and the outcome, in a cohort of critically-ill patients with confirmed diagnosis of VAP. All patients who had been on mechanical ventilation (MV) for more than 48 hours were included in our study; material collection for microbiological analysis was done within the first 24 hours after beginning treatment or after changing antibiotics. There were 55/265 (20.7 percent) VAP cases diagnosed, at a rate of 21.6 episodes per 1,000 days of mechanical ventilation. Mean age of the patients was 66 years, with a mean APACHE II score of 26.7 + 7.0; male patients were more prevalent. The mortality rates in the intensive care unit (ICU) and during the hospital stay were 71 percent and 80 percent, respectively. MV duration in patients with VAP was 17 (range 3-43) days and among patients who had not developed VAP, 6 (2-32) days (p < 0.0001). 98.2 percent of the samples were positive, with a high prevalence of Gram-negative bacteria, mainly Acinetobacter calcoaceticus. Risk factors for death included age, MV duration and surgery. VAP incidence in this sample of critically-ill patients was high, with a high mortality rate. Control and prevention strategies based on continuing education of healthcare workers, developed by a multidisciplinary team, should be encouraged to minimize morbimortality of this infection.