A study on incidence, risk factors and microbiological profile of ventilator associated pneumonia in a tertiary care Referral centre : Kerala, South India

Background: Ventilator-associated pneumonia (VAP) is the most common nosocomial infection diagnosed in the intensive care unit (ICU) and in spite of advances in diagnostic techniques and management it remains a common cause of hospital morbidity and mortality. Aims/objective: The aim of the study was to determine the incidence, the bacterial pathogens causing VAP in our setup, along with the susceptibility pattern for antibiotics and detect the multi-drug resistant pathogens among them. Materials and Methods: This prospective study was conducted in department of Critical Care Medicine, Lakeshore hospital & research centre over a period of 2 years from November 2014 to October 2016, enrolling patients undergoing mechanical ventilation for >48h in MICU’s. Exclusion criteria- age <12 years, patients with COPD, Tuberculosis, ARDS, Bronchial asthma on admission & patients with Pneumonia prior to or within 48 hours of mechanical ventilation are excluded from the study .Endotracheal aspirates were collected from patients with suspected VAP and semi-quantitative cultures were performed on all samples. VAP was diagnosed using Clinical Pulmonary Infection Score (CPIS). Results: Out of 100 cases studied, 19 (19%) patients were diagnosed to have VAP, out of which 42.11% had early-onset (< 96 hours of mechanical ventilation) VAP and 57.89% had late-onset (>96 hours of mechanical ventilation) VAP. Ventilator associated pneumonia was more preponderant in males (63.15), the commonest age group being >60 years followed by age group 41 to 50 years (26.3%). Reintubation of more than one times, infection at other sites and prolonged ventilation are the risk factors for VAP. Acinetobacter species followed by Pseudomonas aeruginosa were the most commonly isolated pathogens in both types of VAP. Antibiotic sensitivity pattern revealed most of the pathogens to be multi-drug resistant. There is significant difference in VAP and Non-VAP groups in terms of outcome variables like death, and discharge from the hospital. Motality rate in our study was 26%, which was significantly higher in late onset VAP due to MDR pathogens. VAP prolongs the duration of mechanical ventilation, length of intensive care and the duration of hospital stay compared to the Non VAP cases. Conclusions: This study provides a baseline data of current scenario of VAP in our set up, which can be utilized to formulate infection control strategies. The present study also shows that VAP is increasingly associated with MDR pathogens which lead to increased mortality, morbidity and indirectly the health care costs.