C55-33 Association of Hypernatremia With Mortality and Resource Utilization Among Mechanically Ventilated Patients: A Nationwide Analysis (2016-2021)

Rationale Hypernatremia is a common electrolyte abnormality among critically ill patients and often reflects suboptimal fluid management. Mechanically ventilated patients are particularly vulnerable due to increased insensible water loss, inability to consume free water orally, and the physiologic consequences of the underlying disease. Although hypernatremia has been linked to adverse outcomes in critical illness, data regarding its impact on mechanically ventilated patients remain limited. This study aims to evaluate the association of hypernatremia with in-hospital mortality, healthcare resource utilization, and length of stay among mechanically ventilated patients. Methods A retrospective cohort study was conducted using the Nationwide Inpatient Sample from 2016 to 2021. The study population included patients who received mechanical ventilation during hospitalization. The primary outcome was in-hospital mortality, while secondary outcomes were total hospital charges and length of stay (LOS). Multivariable logistic regression was performed to assess the independent association between hypernatremia and in-hospital mortality, expressed as odds ratio (OR) with 95% confidence interval (CI). Linear regression was used to analyze variations in total hospital charges and LOS. All models were adjusted for patient demographics (age, gender, race, residence, median household income), the Charlson Comorbidity Index, and hospital characteristics (region, teaching status, bed size). Results In mechanically ventilated patients, hypernatremia was significantly associated with increased in-hospital mortality (adjusted OR 1.45; CI 1.44-1.47, P<.01), higher total hospital charges (adjusted coefficient $73,240.24; CI $70,494.03-75,986.45, P<.01), and prolonged hospital stays (adjusted coefficient 3.7 days; CI 3.6-3.8, P<.01). Conclusion Hypernatremia independently predicts higher in-hospital mortality, greater healthcare resource utilization, and prolonged hospitalization among mechanically ventilated patients. These findings highlight the importance of close electrolyte monitoring and proactive fluid management to improve outcomes in this high-risk group. Additional prospective studies are needed to evaluate the impact of hypernatremia on mechanically ventilated patients.