Mortality and Predictors of In-Hospital Death Among Mechanically Ventilated Adults With Gram-Negative Pneumonia

Background Critically ill adults with gram-negative pneumonia who require invasive mechanical ventilation have a high risk of adverse outcomes and in-hospital mortality. Objective The objective of this study is to determine the in-hospital mortality rate and identify predictors of mortality among intubated and mechanically ventilated adult patients with gram-negative pneumonia. Methods This retrospective cohort study included 178 adult patients with microbiologically confirmed gram-negative pneumonia requiring endotracheal intubation and invasive mechanical ventilation. Demographic characteristics, comorbidities, severity scores, microbiological profile, antimicrobial resistance patterns, laboratory parameters, and clinical outcomes were reviewed. A total of 178 gram-negative isolates were identified. Results The overall in-hospital mortality rate was 76/178 (42.7%). The most frequently isolated pathogens were Acinetobacter baumannii in 58/178 isolates (32.6%), Klebsiella pneumoniae in 47/178 isolates (26.4%), and Pseudomonas aeruginosa in 35/178 isolates (19.7%). Multidrug-resistant organisms were identified in 93/178 patients (52.2%), while carbapenem resistance was observed in 67/178 isolates (37.6%). Non-survivors were significantly older than survivors and had higher APACHE II and Sequential Organ Failure Assessment (SOFA) scores. Septic shock was present in 48/76 non-survivors (63.2%) versus 24/102 survivors (23.5%), multidrug-resistant infection in 51/76 non-survivors (67.1%) versus 42/102 survivors (41.2%), and inappropriate empirical antibiotic therapy in 36/76 non-survivors (47.4%) versus 23/102 survivors (22.5%). Conclusion In-hospital mortality among mechanically ventilated patients with gram-negative pneumonia was high. Advanced age, greater illness severity, septic shock, multidrug-resistant infection, inappropriate empirical antibiotic therapy, hypoalbuminemia, and elevated lactate levels were significant predictors of mortality.