A study on bacterial isolates and their antibacterial susceptibility pattern of tracheal aspirates from tracheostomized patients attending a tertiary care hospital

Aim of the study- To isolate the aerobic bacterial pathogen and to determine the antibacterial susceptibility pattern of the aerobic bacterial isolates from tracheal aspirates of tracheostomized patients. Materials and Methods - This cross sectional study was conducted over a period of 8 months in a tertiary care hospital, Chennai .Tracheal aspirates of 100 tracheostomized patients having fever more than 38 deg C ,after 48 hrs of tracheostomy procedure were collected from Neurosurgery department and processed in the Microbiology laboratory as per standard operating procedure. Antibacterial susceptibility of the bacterial isolates were performed by Kirby- Bauer Disc Diffusion method. Results - Out of 100 samples, 89(89 percentage) were culture positive with a total of 129 isolates in which 40(44.94 percentage) were polymicrobial and 49(55.06 percentage) were monomicrobial with a predominance of Gram Negative Bacilli (GNB). Klebsiella pneumoniae (28.68 percentage) and Pseudomonas aeruginosa (23.25 percentage) were the commonly isolated organisms. Gram negative bacilli were showed highest sensitivity to Cefoperazone-sulbactum(97.3 percentage) and Amikacin(83.24 percentage). All the isolated GNB were 100 percenage sensitive to Imipenem and Piperacillin-Tazobactam. Staphylococcus aureus isolates 12 (9.35 percentage) showed highest sensitivity to Vancomycin(100 percentage) followed by Amikacin(75 percentage). Among the isolated GNB,31.58 percentage of Escherichia coli isolates were found to be Extended Spectrum Beta Lactamase(ESBL) producers, followed by Klebsiella pneumoniae(24.32 percentage), Pseudomonas aeruginosa (23.33percentage). Among the Staphylococcus aureus 33.33 percentage were found to be methicillin resistant (MRSA). Conclusion- This study highlighted polymicrobial growth with majority of isolates being Gram negative bacilli. Klebsiella pneumoniae was the commonest pathogen isolated followed by Pseudomonas aeruginosa. ESBL production was found in 31.58 percentage of Escherichia coli isolates and 24.32 percentage of Klebsiella pneumoniae isolates. Among the isolated Staphylococcus aureus 33.33 percentage of isolates were found to be methicillin resistant. Combination of Amikacin and Cefoperazone Sulbactum was found to be effective against both Gram negative bacilli and Among Staphylococcus aureus isolates all were sensitive to Vancomycin and showed high sensitivity to Amikacin.