Pneumonia in ventilated and non-ventilated patients admitted to intensive care unit in a tertiary care hospital.

BACKGROUND AND OBJECTIVE: Ventilator-associated pneumonia (VAP) remains a significant problem in intensive care units (ICU) and patients on mechanical ventilation (MV). Early and accurate diagnosis is essential to initiate appropriate antimicrobial therapy and prevent disease progression. The emergence of multidrug-resistant (MDR) pathogens further complicates treatment, necessitating continuous surveillance of microbial aetiology and antimicrobial susceptibility patterns. This study aimed to compare the clinical characteristics, ICU stay, mortality outcomes, and antimicrobial resistance profiles between ventilated and non-ventilated pneumonia patients. METHODS: A prospective, observational, and comparative study was conducted on 60 patients at the Medical ICU at tertiary care hospital from May 2022 to May 2023. Demographic data, comorbidities, microbial isolates, antimicrobial susceptibility patterns, ICU length of stay, and mortality rates were analysed. Statistical significance was determined using appropriate tests. Statistical analysis was carried out using SPSS version 16.0 (Chicago, Inc., USA). Continuous variables were compared using the unpaired t-test, while categorical variables were analysed using the Chi-square test. A P value of ≤0.05 was considered statistically significant. RESULTS: A total of 60 pneumonia patients were included, categorized into ventilated (n = 30) and non-ventilated (n = 30) groups. Male predominance was observed in both groups (73.3% ventilated, 83.3% non-ventilated), with a male-to-female ratio of 3.61:1. The mean age of ventilated patients was 60.70 ± 15.99 years, while non-ventilated patients had a mean age of 58.93 ± 14.58 years (P = 0.65). Klebsiella spp. was the most frequently isolated organism in both ventilated (40.0%) and non-ventilated (33.3%) patients, followed by Acinetobacter spp. (26.7%) and Escherichia coli (20.0%), respectively. Among ventilated patients, high resistance was observed against beta-lactam antibiotics, with colistin (87.5% for Acinetobacter spp. and 75% for Klebsiella spp.) and tigecycline showing the highest susceptibility. In non-ventilated patients, colistin was effective against all isolates of Klebsiella spp. (100%) and E. coli (100%). The mean ICU stay was significantly longer in ventilated patients (13.74 ± 4.93 days) than in non-ventilated patients (6.10 ± 1.97 days, P = 0.0001). Mortality was significantly higher in ventilated patients (50.0%) compared to non-ventilated patients (13.3%, P = 0.002). CONCLUSION: Ventilated pneumonia patients experienced significantly prolonged ICU stays and higher mortality, primarily due to MDR infections. Klebsiella spp. and Acinetobacter spp. were the dominant pathogens, with colistin and tigecycline demonstrating the highest efficacy. These findings emphasize the need for stringent infection control measures, early identification of high-risk patients, optimized ventilator management, and judicious antimicrobial use to improve outcomes in critically ill pneumonia patients.