The ICU Burden: How Drug-resistant Pneumonia Shapes Shock And Mortality: A Retrospective Analysis

INTRODUCTION: Hospital-acquired pneumonia (HAP) and ventilator-associated pneumonia (VAP) are significant causes of morbidity and mortality in critically ill patients, particularly in the pulmonary medicine ICU.(1,2) The emergence of drug-resistant organisms further complicates management, increasing mortality risk and the likelihood of complications such as septic shock.(3) OBJECTIVE: This study aimed to analyze the prevalence of HAP and VAP, identify the common drug-resistant organisms, and examine their correlation with patient outcomes, specifically the occurrence of shock and mortality. METHODS: A retrospective observational study was conducted on patients admitted to the pulmonary medicine ICU from 1st January 2024 till 30th November 2024. Clinical and microbiological data were reviewed to identify cases of HAP and VAP, isolated causative organisms, and assess antimicrobial resistance patterns. Patient outcomes, including mortality and shock incidence, were analyzed in relation to the isolated organisms and co-morbidities. Statistical tools were used to determine correlations and significance. RESULTS: A total of 182 patients were analysed. The majority of patients were male (68.1%) and the mean age of the population studied was 56.9±14.2 years. The median duration of hospital stay was 6.5 days. The most common comorbidity in population studied was COPD (57.7%) followed by systemic hypertension (24.2%). The prevalence of HAP and VAP was found to be 13.2% and 16.5%, respectively. The most frequently isolated organisms were Carbapenem resistant Acinetobacter baumannii (CRAB) (41.2%), Carbapenem resistant Klebsiella pneumoniae (18.75%), Difficult to treat Pseudomonas aeruginosa (13.75%), Carbapenem resistant Escherichia coli (8.75%), Candida (12.5%) and 1.25% showed growth for Serratia, Methicillin resistant Staphylococcus aures, and Stenotrophomonas maltophilia. Only 2 patients showed growth of drug sensitive Pseudomonas aeruginosa. The cumulative mortality in HAP and VAP noted to be 70.3%. Notably, patients infected with CRAB and Candida showed a higher risk of developing septic shock (P<0.05). Also, patients having underlying COPD and cor pulmonale had higher incidence of septic shock (P < 0.05). The mortality rate for patients with HAP was significantly higher compared to those with VAP (P<0.05). The factors associated with increased mortality included isolation of Candida and underlying COPD and cor pulmonale(P<0.05). CONCLUSION: HAP and VAP remain prevalent in the pulmonary ICU setting, with drug-resistant organisms contributing substantially to adverse outcomes. The strong correlation between MDR pathogens and increased shock and mortality underscores the need for stringent infection control measures and the development of targeted antibiotic stewardship programs. Further prospective studies are warranted to refine management strategies and improve patient outcomes.