1210: Effectiveness of Magnesium Sulfate for Critical Asthma in the Pediatric Intensive Care Unit

Introduction: Magnesium sulfate (MgSO4) is an adjunctive therapy used in children with critical asthma refractory to conventional treatment. The primary aim of this study is to evaluate the efficacy of MgSO4 administration in pediatric patients admitted to the pediatric intensive care unit (PICU) with critical asthma. We hypothesized that MgSO4 administration would decrease both time on continuous albuterol and hospital length of stay, regardless of severity of illness. Methods: We conducted a retrospective cohort analysis of pediatric patients admitted to two PICUs: St. Christopher’s Hospital (Center-1) and UW Health American Family Children’s Hospital (Center-2), between 2015 and 2022. Patients were categorized into two groups: MgSO₄-treated and untreated. Continuous variables were compared between groups using the Wilcoxon rank-sum test and categorical variables compared using chi-square or Fisher’s exact tests. Outcomes involving duration length of stay (LOS), duration of oxygen support, and duration of continuous albuterol, were further explored using multivariable regression after log-transformation of time. Results: A total of 369 patients were included in the study. Median IQR age was 7 4–11 years. Patients at Center-2 were 38% more likely to receive MgSO4 compared to those at Center 1 (36.1% vs 26.2%; RR=1.38, 95% CI: 1.01–1.88, p=0.04) during their hospitalization. PRISM-3 scores were significantly higher in the MgSO4 group (p=0.008), with each additional point in PRISM-3 associated with an 8% higher likelihood of receiving MgSO4 (RR=1.08; 95% CI = 1.03–1.12). Children treated with MgSO₄ received longer courses of corticosteroids (p=0.014). Median PICU (2.5 vs. 1.5 days; 95% CI=1.5–1.9) and hospital LOS (3.8 vs. 2.4 days; 95% CI=1.4–1.8) were both significantly greater in the MgSO4 group (p< 0.001). After regression analysis adjustment for differences between groups, we found that the duration and overall dose of continuous albuterol were also significantly higher in MgSO4-treated patients (p< 0.001). Conclusions: This multicenter cohort study of critically ill children with critical asthma found MgSO₄ was more often administered to patients with greater illness severity. Its use was associated with longer durations of continuous albuterol and LOS.