Invasive devices in the pathogenesis of nosocomial pneumonia

Abstract

Nosocomial pneumonia remains a common complication in patients who require mechanical ventilation. On various occasions endotracheal intubation has been identified as a risk factor for nosocomial pneumonia. Levine and Niederman [1] described four different device/host interactions that may be responsible. First, an endotracheal tube can have direct effects on the airway, resulting in an impairment of local host defense mechanisms. Mucosal injury can reduce mucociliary function, while upper airway defenses are bypassed and the effectiveness of cough is reduced. Second, intubation can result in an enhanced capacity of tracheobronchial cells to bind Gram-negative bacteria, an effect that favors airway colonization and, thus, pneumonia. Third, the airway injury can create binding sites for bacteria in the basement membrane of the bronchial tree. Fourth and most important in relation to bacterial biofilm, endotracheal tubes may serve as a reservoir for bacteria [1]. © 2007 Springer-Verlag Berlin Heidelberg.