Antimicrobial Resistance Pattern of Bacterial Isolates from Endotracheal Aspirate of Ventilated Patients at a Tertiary Care Hospital

Abstract

Background: Respiratory infections among critically ill Patient are associated with high morbidity and mortality. Mechanically ventilated patients are at a high risk of acquiring respiratory infections due to complex interplay between the endotracheal tube, host immunity and virulence of invading bacteria. Irrational use of antibiotics increases the emergence of drug – resistant bacteria. Objectives: The aim of study was to investigate the bacterial isolates in the endotracheal aspirates of mechanically ventilated patients in ICU and see the antimicrobial resistance pattern of bacterial isolates. Methods: Analysis of E.T aspirates of 459 patients over a period of 1 year (Aug 14 to Aug 15) was done. Aspirates were cultured on Blood and MacConkey agar isolation and identification was done using conventional techniques and biochemical reactions. Antibiotic sensitivity testing was done by Kirby-Bauer disc diffusion method as per CLSI guidelines. Results: Out of 459 Samples 365 was found to be positive. Acinetobacter sp (44.65%) was the most common isolate followed by Klebsiella sp (18.63%), Pseudomonas sp (11.23%), Candida (10.46%), Escherichia Coli (7.94%), COPS (3.28%), CONS (2.46%), Enterococci (0.82%), and Citrobacter (0.54%). The gram-negative bacilli were mostly sensitive to Tigecycline, Colistin, Imipenem, Meropenem, Amikacin and Piperacillin/Tazobactam. Gram positive Cocci were mostly sensitive to Vancomycin, Linezolid and Gentamicin. Conclusion: The isolation and antimicrobial resistance pattern of the microorganisms is necessary for their effective management. Endotracheal intubation is one of the major risk factors in causing iatrogenic infections to patients. A local antibiogram for each hospital, based on bacteriological patterns and susceptibility is essential to initiate empirical therapy.