Ventilator-associated pneumonia: clinical considerations.

Nosocomial (i.e., originating or taking place in a hospital) pneumonia is the leading cause of death from acquired nosocomial infections. The estimated prevalence of nosocomial pneumonia in intensive care units ranges from 10% to 65%, with fatality rates of 13-55%. Ventilator-associated pneumonia (VAP) specifically refers to nosocomial pneumonia in a mechanically ventilated patient that was neither present nor already developing at the time of intubation (i.e., clinical evidence of VAP occurring > 48 hr after intubation). During the past decade, some studies have suggested that VAP can be an important determinant of out-come for critically ill patients requiring mechanical ventilation. Recent investigations have provided new insights into the pathogenesis of VAP, and improved techniques have been developed for its diagnosis. Most important, emerging clinical data now suggest that new management strategies for VAP, including more specific indications for antimicrobial use, may significantly improve patients' outcomes.