Impact of clinical severity index, infective pathogens, and initial empiric antibiotic use on hospital mortality in patients with ventilator-associated pneumonia

Background The prompt initial use of appropriate antibiotics should improve mortality rates in adults with ventilator-associated pneumonia (VAP). However, the incidence of multidrug-resistant (MDR) pathogen infections is on the rise, and the choice of the initial empiric antibiotic may be challenging. We investigated whether appropriate initial antibiotic therapy, infective pathogens, and the clinical severity index influence hospital mortality in patients with VAP and determined independent risk factors for the same. Methods This study evaluated 163 adult patients (aged ≥ 18 years) at Chang Gung Memorial Hospital, Kaohsiung, Taiwan, from January 1, 2007, to January 31, 2008. Eligibility was evaluated based on criteria for VAP. Sequential Organ Failure Assessment (SOFA) scores, Acute Physiological Assessment and Chronic Health Evaluation II (APACHE II) scores, oxygenation index, underlying comorbidities, septic shock status, previous tracheostomy status, and factors related to pneumonia were collected for analysis. Results Ninety-two patients survived from a total 163 patients with VAP during the course of their confinement in the intensive care unit. Multivariable logistic regression analysis identified that a pre-existing Charlson Comorbidity Index score ( P = .011), initial oxygenation index ( P = .025), SOFA score ( P = .043), VAP caused by Acinetobacter baumanii ( P = .030), and infection with MDR pathogens ( P = .003) were independent risk factors for hospital mortality in patients with VAP. Conclusion High Charlson Comorbidity Index score, high initial oxygenation index, high SOFA score, and infection with Acinetobacter baumannii or MDR pathogens significantly affect hospital mortality in patients with VAP.