Abstract
BACKGROUND: The use of ondansetron (OND) has proven to be beneficial in the prognosis of critically ill patients. However, whether early OND use has a benefit in acute respiratory distress syndrome (ARDS) patients on mechanical ventilation (MV) is unknown. This study aimed to investigate the association of the early use of OND with the risk of 30-day mortality in ARDS patients who received MV support. METHODS: This cohort study retrospectively extracted patients with ARDS from the Medical Information Mart for Intensive Care (MIMIC)-IV database from 2008 to 2019. All potential covariates were incorporated in the univariate and multivariable Cox proportional hazard models with a two-way stepwise regression analysis. Univariate and multivariable Cox proportional hazard models were used to evaluate the association of early OND use with 30-day mortality before or after the propensity score matching (PSM), with hazard ratios (HRs) and 95% confidence intervals (CIs). Subgroup analysis was performed stratified by age, gender, ARDS grades, ventilator-associated pneumonia (VAP), acute kidney injury (AKI), ventilation time, and vasopressor. RESULTS: Of the total 6,457 ARDS patients, 1,125 died within 30 days. After PSM, patients who received early OND use had lower odds of 30-day mortality compared with those who did not (HR =0.77, 95% CI: 0.63-0.94). The low dose of early OND use was associated with a decreased risk of 30-day mortality (HR =0.67, 95% CI: 0.54-0.83). Early OND use was related to lower odds of 30-day mortality of ARDS patients aged ≥65 years (HR =0.54, 95% CI: 0.43-0.67), with females (HR =0.77, 95% CI: 0.61-0.97) or males (HR =0.58, 95% CI: 0.47-0.72), with ARDS grades of mild (HR =0.57, 95% CI: 0.44-0.74), moderate (HR =0.76, 95% CI: 0.60-0.97) or severe (HR =0.69, 95% CI: 0.49-0.98), without VAP (HR =0.64, 95% CI: 0.55-0.76), with AKI (HR =0.62, 95% CI: 0.52-0.74), with short (<43.87 h, HR =0.65, 95% CI: 0.50-0.83) or long (≥43.87 h, HR =0.71, 95% CI: 0.58-0.87) ventilation time, and those who received vasopressor (HR =0.67, 95% CI: 0.56-0.80) or not (HR =0.65, 95% CI: 0.46-0.90). CONCLUSIONS: Early OND use and daily low-dose OND use before MV support were associated with a decreased risk of 30-day mortality, which may be beneficial for the rational use of OND in ARDS patients.