Ventilator associated pneumonia in a medical intensive care unit: Microbial aetiology, susceptibility patterns of isolated microorganisms and outcome

Abstract

Background:Ventilator-associated pneumonia (VAP) is a common complication of ventilatory support for patients with acute respiratory failure and is associated with increased morbidity and mortality.Aim of the Study:The present study was undertaken to do quantitative cultures of aerobic bacteria, perform the antibiotic susceptibility testing from the endotracheal aspirates and clinical outcome of the clinically suspected patients of VAP.Methods:A prospective study was performed over a period of one year in a tertiary care hospital, enrolling patients on mechanical ventilation (MV) for ≥48 hr. Endotracheal aspirates (ETA) were collected from patients with suspected VAP, and direct gram's stain criteria was used to accept the sample. Quantitative cultures of ETA were performed with the threshold for microbiological diagnosis of VAP was taken as ≥105 colony forming units (cfu)/ml.Results:Out of 53 cases, 2 (3.77%) were polymicrobial. Multidrug resistant bacteria, mainly Acinetobacter baumannii 49.09% (27/55) and Pseudomonas aeruginosa 30.91% (17/55) were the most common pathogens isolated. Metallo-beta lactamases (MBLs) was produced by 47.06% (8/17) of Pseudomonas aeruginosa and 62.96% (17/27) of Acinetobacter baumannii.Conclusion:The bacteriological approach for the management of VAP helps the clinicians in choosing the appropriate antibiotics. This study showed that quantitative cultures of endotracheal aspirate at a cutoff point of 105 cfu/ml is one of the alternative to bronchoscopy in the diagnosis of clinically suspected ventilator associated pneumonia.

Superbugs causing ventilator associated pneumonia in a tertiary care hospital and the return of pre-antibiotic era!

“…All the isolates were Presently there is concern about the acquisition of plasmid mediated, metallo beta-lactamases active against carbapenems, penicillins and cephalosporins. [12,13] In the present study, 28.57% % isolates of Acinetobacter spp., and 37.5% of Pseudomonas aeruginosa were MBL producing strains. A total of 75% of the isolates were ESBL producers in the present study.…”

“…[11,12] Early onset VAP was observed in 47.37% patients whereas 52.63% patients had late onset pneumonia. NFGNB such as Acinetobacter and Pseudomonas spp.…”

“…But the resistance of the NFGNB to the other antibiotics was almost the same in both early and late onset VAP comparable to other studies. [12,13] Many of the early onset VAP cases had the risk factors such as prior antibiotic therapy and current hospitalisation for 5 days or more or referrals from nursing homes, for infection with MDR pathogens. That could be the reason for the almost similar patterns of antibiotic susceptibility of isolates from early and late onset VAP.…”

“…The overall mortality rate in the VAP patients was 48.57% in our ICU setting which was in accordance with previous studies like Goel et al, 45.28%. [12] However it was difficult to comment on the attributable mortality due to VAP. The present study also demonstrated a statistically significant (P < 0.05) mortality rate in late onset type associated with the grotesque battle against the deadly superbugs.…”

Distribution of New Delhi metallo-beta-lactamase producing Acinetobacter baumannii in patients with ventilator associated respiratory tract infection

“…The exudates were collected into a sterile 50 ml Falcon tube and transported immediately to the laboratory for further processing. Only one ETA sample was collected from each patient [15,16].…”