Ventilator-associated pneumonia in adults in developing countries: a systematic review

Abstract

Ventilator-associated pneumonia (VAP) is a leading cause of death in hospitalized patients, but there has been no systematic analysis of the incidence, microbiology, and outcome of VAP in developing countries or of the interventions most applicable in that setting. We reviewed MEDLINE (January 1966-April 2007) and bibliographies of the retrieved articles for all observational or interventional studies that examined the incidence, microbiology, outcome, and prevention of VAP in ventilated adults in developing countries. We evaluated the rates of VAP using the National Healthcare Safety Network (NHSN) definitions and the impact of VAP on the intensive care unit (ICU) length of stay (LOS) and mortality, and the impact of interventions used to reduce VAP rates. The rates of VAP varied from 10 to 41.7 per 1000 ventilator-days and were generally higher than NHSN benchmark rates. Gram-negative bacilli were the most common pathogens (41-92%), followed by Gram-positive cocci (6-58%). VAP was associated with a crude mortality that ranged from 16% to 94% and with increased ICU LOS. Only a small number of VAP intervention studies were performed; these found that staff education programs, implementation of hand hygiene, and VAP prevention practice guidelines, and/or implementation of sedation protocol were associated with a significant reduction in VAP rates. Only one interventional study was a randomized controlled trial comparing two technologies, the rest were sequential observational. This study compared a heat and moisture exchanger (HME) to a heated humidifying system (HHS) and found no difference in VAP rates. Based on the existing literature, the rate of VAP in developing countries is higher than NHSN benchmark rates and is associated with a significant impact on patient outcome. Only a few studies reported successful interventions to reduce VAP. There is a clear need for additional epidemiologic studies to better understand the scope of the problem. Additionally, more work needs to be done on strategies to prevent VAP, probably with emphasis on practical, low-cost, low technology, easily implemented measures.