C105-12 The Synergistic Effect of Driving Pressure and Respiratory Rate on the Mortality of Acute Respiratory Distress Syndrome Patients

Abstract Rationale Acute respiratory distress syndrome (ARDS) remains a major challenge in intensive care units (ICUs) and is associated with high mortality despite advances in critical care. Lung-protective ventilation, characterized by using low tidal volume and limitation of airway pressure, is the cornerstone of ARDS management and has been shown to improve survival. However, the influence of ventilator rate on patient outcomes has not been well addressed and remains an underexplored aspect of mechanical ventilation strategy. Therefore, this study aims to investigate the impact of ventilator parameters—including respiratory rate—on mortality in patients with ARDS, to further refine lung-protective strategies and improve clinical outcomes. Method This retrospective study was conducted in the intensive care units of Taichung Veterans General Hospital (TCVGH) between 2018 and 2020. The analysis included patients who required invasive mechanical ventilation and met the 2012 Berlin definition criteria for ARDS. Those managed with pressure support ventilation were excluded. Demographic characteristics, laboratory data, comorbidities, ventilator parameters, and fluid balance records were collected and analyzed. Result A total of 665 patients were included in the study, with a mean age of 66.2 ± 16.2 years. Among them, 400 patients (60.2%) survived, while 265 (39.8%) died during hospitalization. Survivors tended to have lower driving pressures (DP) than non-survivors, and mortality increased with higher driving pressures (DP ≤ 14: 37.5%; DP 14: 46.2%; p = 0.03). In addition, patients with a respiratory rate (RR) 23 breaths per minute had higher mortality compared with those with lower rates (46.1% vs. 33.2%; p = 0.03). After adjustment for multiple confounders, both elevated RR (adjusted OR: 1.037; 95% CI: 1.000-1.075; p = 0.005) and higher DP (adjusted OR: 1.061; 95% CI: 1.015-1.109; p = 0.008) were independently associated with increased hospital mortality. Conclusion In critically ill patients with ARDS, respiratory rate, along with driving pressure, independently predicts mortality risk. This study also demonstrates a synergistic effect of these two factors on mortality. Our result emphasizes the value of implementing personalized ventilator strategies to prevent excessively high respiratory rates, especially in patients with higher driving pressure. This abstract is funded by: None