Comparison of Microbial Profile, Antibiotic Susceptibility, and Mortality in Early- and Late-Onset...

To determine the microbial profile, antibiotic susceptibility patterns, and mortality rates of early- vs. late-onset ventilator-associated pneumonia (VAP).

A retrospective cross-sectional study. Place and Duration of the Study: Surgical Intensive Care Unit, Doctors Hospital and Medical Centre, Lahore, Pakistan, from January 2023 to June 2024.

Data were collected using a non-probability consecutive sampling method. Data were analysed using IBM SPSS 29.0 Software, and an Excel Sheet was used to make a table of isolates and their sensitivity to antibiotics.

A total of 46 VAP cases were recorded during the study period. Of which, 13 (28.2%) were early-onset, and 33 (71.7%) were late-onset VAP cases. Males were 31 (67.3%), while females were 15 (32.6%). Among the early-onset VAP cases, the most common isolates were Pseudomonas aeruginosa (4, 30.7%), Candida albicans (4, 30.7%), and Klebsiella pneumonia (2, 15.38%), followed by single isolates of Acinetobacter, Burkholderia, and E. coli. In the late-onset VAP, the isolates were Acinetobacter (8, 24.2%), Klebsiella (8, 24.2%), Pseudomonas (7, 21.2%), Staphylococcus aureus (3, 9.09%), Burkholderia (2, 6.06%), Candida (2, 6.02%), Proteus mirabilis (1, 3.03%), E. coli (1, 3.03%), and Enterobacter cloacae (1, 3.03%). Almost all Gram-negative organisms were sensitive to colistin except E. coli. All Pseudomonas and Acinetobacter isolates were resistant to carbapenems (100% resistance), while Klebsiella was 40% sensitive (4 out of 10), E. coli 50% (1 out of 2), Burkholderia 66.6% (2 out of 3), and Proteus mirabilis 100%. Klebsiella was 70% sensitive to chloramphenicol. Minocycline had 100% susceptibility for Acinetobacter, Enterobacter, and Staphylococcus aureus, 60% susceptibility for Klebsiella, and 33.3% for Burkholderia.

VAP is mainly caused by multidrug-resistant (MDR) bacteria, especially Pseudomonas aeruginosa, Klebsiella pneumoniae, and Acinetobacter baumannii, irrespective of the onset duration. It is suggested that empirical therapy should include broad-spectrum coverage for MDR, including colistin, along with Gram-positive coverage, such as vancomycin, linezolid, or teicoplanin, to prevent the onset of early or late VAP.

Ventilator-associated pneumonia, Intensive care unit, Mechanical ventilation, Early onset VAP, Late onset VAP, Antimicrobial resistance.