Ventilator Associated Pneumonia (VAP) and its Correlation with Mortality in Indian Population

Pneumonia is the most commonly reported nosocomial infection among ICU patients, occurring predominantly in individuals requiring mechanical ventilation, at a rate of 1 to 3% per day of mechanical ventilation. The estimated prevalence of nosocomial pneumonia within the ICU setting ranges from 10 to 65%, with case fatality rates > 20% in most reported studies. Early-onset nosocomial pneumonia is most often reported to be due to antibiotic-sensitive pathogens including Haemophilus influenza, oxacillin-sensitive Staphylococcus aureus (OSSA), and Streptococcus pneumonia, while late-onset nosocomial pneumonia is frequently attributed to antibiotic-resistant pathogens such as oxacillin-resistant S aureus (ORSA), Pseudomonas aeruginosa, Acinetobacter species, and Enterobacter species The frequency of VAP caused by multidrug-resistant bacteria has increased in recent years, and these pathogens cause most of the deaths attributable to pneumonia.

Nosocomial infections were defined according to criteria outlined by the Centers for Disease Control [CDC] According to these criteria Pneumonia was defined as the presence of purulent sputum, fever above 38°C, a Gram stain with over 25 polymorphonuclear leukocytes and less than ten squamous epithelial cells per low power field, and a persistent infiltrate on chest roentgenograms, consistent with pneumonia.

In our study, out of the 112 patients studied, 69 patients belonged to the medical group (61.6%) and 43 patients (38.4%) to the surgical group. Most patients were admitted for ventilatory support (90.2%). The incidence of VAP was found to be 42% in our ICU during the period of study. Acinetobacter was the most common organism isolated followed by Staphylococcus aureus, Pseudomonas aeruginosa and Ecoli were found to be associated with tracheal aspirates in VAP. Carbepenems and 4^th generation cephalosporins were found to be most effective in the treatment of the nosocomial infection. Diabetes melitus was found to be significantly associated with VAP (p value 0.034). Morality in VAP patients was found to be 19.1%. We found that VAP was not significantly associated with mortality.

In this study we found that the more frequent indication for ICU admission was Ventilatory support and VAP was found in 42% of the cases. Acinetobacter was the most frequently isolated organism. 4^th generation cephalosporins and carbepenems were found to be effective in the treatment of the nosocomial infection. The association of age, gender, SOFA score and predisposing factors other than Diabetes mellitus with VAP were statistically not significant.