Semirecumbency Prevents Nosocomial Pneumonia in Mechanically Ventilated Patients

Abstract

Nosocomial pneumonia is the most common infection in the intensive care unit (ICU) [1]. Nosocomial pneumonia (NP) in mechanically ventilated (MV) or ventilator-associated pneumonia (VAP) typically refers to pneumonia developing after 48 hours following endotracheal intubation and MV [2]. Infections restricted to a series of MV patients within the ICU revealed that VAP accounts for approximately 90% of the infections in patients requiring assisted ventilation [3]. The European [4] and Spanish [5] multicenter studies have associated MV in ICU patients with almost 3-fold and 23-fold increased risk of NP, respectively, compared with non ventilated subjects. Furthermore, National Nosocomial Infections Surveillance (NNIS) system [6] reported approximately 9.3 times higher incidence density rates of VAP than nonventilator-associated pneumonia within the ICU, ranging from 2.6 times higher in the respiratory ICU to 19 times higher in the burn ICU. Nosocomial pneumonia is also a leading cause of death in ICUs [7], resulting in a significant 2 to 10-fold increase in the mortality rate [8, 9, 10] and the occurrence is shown to be an independent determinant of hospital mortality [11]. Recent inferences have been made, indicating that VAP markedly increases morbidity by affecting the ICU length of stay [12, 13] and the duration of MV [14, 15]. Two investigations reported that VAP caused a significant excess of the ICU length of stay in one clinical trial [12] and prolongation of the ICU hospitalization for 4 days in another clinical trial [13]. In addition, VAP increased almost 3-fold more than MV in a multicenter prospective study [14] or 9 days in a matched cohort investigation [15]. Finally, there is no doubt that VAP substantially increased the hospital costs for the survivors [16]. Papazian et al. estimated that each episode of VAP costs the hospital an additional $ 7 752 [15].