C55-05 Predictors of In-Hospital Mortality Among Mechanically Ventilated Patients With Acute Respiratory Failure: A Nationwide Analysis

Abstract Introduction Acute respiratory failure (ARF) requiring invasive mechanical ventilation (IMV) represents a major cause of intensive care utilization and mortality. While ventilatory strategies have evolved, national outcome data and predictors of mortality among this high-risk population remain incompletely defined. This study aimed to evaluate in-hospital outcomes and identify demographic and clinical predictors of mortality among mechanically ventilated ARF patients using the 2021 National Inpatient Sample (NIS). Methods A retrospective cross-sectional analysis was conducted using adult hospitalizations (≥18 years) from the 2021 NIS with ARF (ICD-10 J96*) undergoing IMV (ICD-10-PCS 5A19*). Discharge weights (DISCWT) were applied to generate national estimates. The primary outcome was in-hospital mortality; secondary outcomes included length of stay (LOS) and total charges. Multivariable logistic regression identified independent mortality predictors, adjusting for age, sex, race, payer, income quartile, sepsis, and ARDS. Statistical significance was set at p 0. 05. Results A total of 940, 229 unweighted ARF hospitalizations with IMV were identified. The mean age was 59. 7 ± 19. 2 years; 42% had sepsis and 0. 6% had ARDS. Overall, in-hospital mortality was 37. 1%. Median LOS was 9 IQR 4-18 days, and median total charges were 151, 231 74, 965-302, 343. On multivariable analysis, increasing age (aOR 1. 03 per year, 95% CI 1. 03-1. 03; p 0. 001), Black race (aOR 1. 19, 95% CI 1. 18-1. 21; p 0. 001), Hispanic race (aOR 1. 16, 95% CI 1. 14-1. 18; p 0. 001), Medicaid coverage (aOR 1. 19, 95% CI 1. 18-1. 21; p 0. 001), sepsis (aOR 1. 88, 95% CI 1. 87-1. 90; p 0. 001), and ARDS (aOR 2. 48, 95% CI 2. 35-2. 62; p 0. 001) were independently associated with higher mortality. Female sex (aOR 0. 93, 95% CI 0. 92-0. 93; p 0. 001) and higher income quartile (aOR range 0. 93-0. 97; p 0. 001) predicted improved survival. The model demonstrated good fit (Omnibus p 0. 001; Nagelkerke R² = 0. 10). Discussion More than one-third of ARF patients requiring IMV died during hospitalization. Mortality was disproportionately higher among older, minority, and low-income groups, indicating persistent disparities in critical care outcomes. The strong association of sepsis and ARDS with mortality underscores the importance of early recognition and aggressive management of these conditions. Despite advances in ventilatory support, overall outcomes remain poor, highlighting the need for targeted quality improvement and equity-focused interventions. Conclusion Invasive mechanical ventilation for acute respiratory failure carries substantial mortality, driven by age, race, socioeconomic status, and comorbid critical illness. Efforts to reduce disparities and optimize sepsis and ARDS management may improve survival among mechanically ventilated patients nationwide. This abstract is funded by: None