CHARACTERIZATION OF PATHOGENS CAUSING VENTILATOR ASSOCIATED PNEUMONIA IN INTENSIVE CARE UNITS OF A TERTIARY CARE HOSPITAL – A PROSPECTIVE STUDY

*Dr. Roshni Agarwal, Dr. Anjali Tiwari, Dr. Parvati Upadhayay, Dr. Vaibhav Agarwal, Dr. Devendra Kumar Niranjan and Dr. Niti Bhai

ABSTRACT

Introduction: Ventilator-associated pneumonia (VAP) is the most common healthcare associated infection diagnosed in intensive care units (ICUs). It is caused mostly by potentially drug-resistant bacteria. Aims and objectives: The current study aimed at determining the bacteriological etiology of VAP and antimicrobial susceptibility pattern of the isolates causing VAP in the ICUs of our hospital. Material and Methods: A prospective study was carried out from January 2017 to December 2017 from ICUs of Regency hospital, Kanpur. A total of 135 lower respiratory tract samples (Endotracheal aspirate (ETA) and Transtracheal aspirate (TTA)) of patients on Mechanical ventilator (MV) suspicious of having VAP were received in Microbiology Department and processed. Organisms were isolated by standard microbiological techniques. The isolates were then subjected to identification and antimicrobial susceptibility testing using VITEK 2 – compact. RESULTS: The majority of bacterial isolates causing VAP were found to be Gram negative bacilli (95%). Acinetobacter baumanii accounted for 60.0% followed by Klebsiella pneumoniae 22.2%, Pseudomonas aeruginosa 8.9%. Other isolates were Escherichia coli, Enterobacter cloacae & S. aureus. Out of the 39 VAP cases, 17(43.6%) were categorized under early onset VAP (<96 hrs. on MV) and 22 (56.4%) under late onset VAP (>96 hrs. on MV). Polymicrobial growth was seen in 15.4% of VAP cases. Thirty-seven (82.2%) of the 45 VAP pathogens in our study were multi-drug resistant (MDR). Conclusions: Most of the pathogens causing VAP in our institute were multidrug resistant. Colistin and Tigecycline were found to be highly effective against multidrug resistant Acinetobacter baumanii and Klebsiella pneumoniae. The bacteriological approach for the management of VAP helps the clinicians in choosing the appropriate antibiotics.

Keywords: Ventilator-associated pneumonia, Intensive care unit, Multi Drug resistant.