Geographic variation in susceptibility to ventilator-associated pneumonia after traumatic injury.

Abstract

Emphasis on prevention of health care-associated infections including ventilator-associated pneumonia (VAP) has increased as hospitals are beginning to be held financially accountable for such infections. Health care-associated infections are often represented as being avoidable; however, the literature indicates that complete preventability may not be possible. The vast majority of research on risk factors for VAP concerns individual-level factors. No studies have investigated the role of the patient's environment before admission. In this study, we aimed to investigate the potential role prehospital environment plays in VAP etiology. In a retrospective cohort study, a sample of 5,031 trauma patients treated with mechanical ventilation between 1996 and 2010 was analyzed to determine the effect of neighborhood on the probability of developing VAP. We evaluated the effect of zip code using multilevel logistic regression analysis adjusting for individual-level factors associated with VAP. We identified three zip codes with rates of VAP that differed significantly from the mean. Logistic regression indicated that zip code, age, sex, race, injury severity, paralysis, head injury, and number of days on the ventilator were significantly associated with VAP. However, median zip code income was not. Spatial factors that are independent of health care quality may potentiate the likelihood of a patient developing VAP and possibly other types of health care-acquired infections. Unmodifiable environmental patient characteristics may predispose certain populations to developing infections in the setting of trauma.