Incidence and risk factors associated with development of ventilator-associated pneumonia from a tertiary care center of northern India -

Background: The incidence of VAP varies among different studies, depending on the definition, the type of hospital or ICU, the population studied, and the level of antibiotic exposure. This study was planned to ascertain and analyse the incidence and risk factors associated with development of ventilator-associated pneumonia from a tertiary care center. Methods: In this retrospective study, all the adult patients on mechanical ventilation (MV) for more than 48 hours in the Medicine Intensive Care Unit (MICU) and the Critical Care Unit (CCU) during September 2015 to February 2016 were included in the current study. Patients diagnosed with pneumonia prior to MV or within 48 hours of MV were excluded from the study. Patients’ records served as study tools. Medical records department (MRD) was approached and data was collected on all patients who received mechanical ventilation during the study period. The relevant data were recorded from medical records, bedside flow sheets, radiographic reports, and reports of microbiological studies of the patients. The chi-square (χ²) test or Fisher’s exact test was used to compare different groups. Univariate and multivariate logistic regression analysis was performed to identify risk factors associated with development of ventilator-associated pneumonia. Results: Overall incidence of VAP was 23.54 per 1,000 ventilator days. The incidence of VAP in MICU and CCU were 31.77 and 16.47 per 1,000 ventilator days respectively. 60% of the cases were late-onset VAP, while 40% were early-onset VAP. The most common organism isolated was Pseudomonas aeruginosa followed by Methicillin-resistant Staphylococcus aureus (MRSA). Impaired consciousness, tracheostomy, re-intubation, emergency intubation, and nasogastric tube were significantly associated with VAP. On multivariate analysis, impaired consciousness, emergency intubation and tracheostomy were independent risk factor for VAP among study subjects. Conclusions: Data thus generated can be used to plan and modulate the potential intervention measures while managing VAP. Knowledge of the important risk factors predisposing to VAP may prove to be useful in implementing effective preventive measures.