Use of intravenous magnesium sulfate in addition to standard first-line treatment with inhaled/nebulised short-acting beta 2 agonist and systemic steroids in the management of acute asthma exacerbations in children: a systematic review and meta-analyses of randomised controlled trials

Background The role of intravenous magnesium sulfate in asthma exacerbation is unclear. Aims To determine the efficacy and safety of intravenous magnesium sulfate in managing asthma exacerbation in children. Methods We searched MEDLINE, EMBASE, CINAHL, the Cochrane Central Register of Controlled Trials and the Web of Science up to May 2024. We included randomised controlled trials and followed the international guidelines for conducting systematic reviews. Outcomes included morbidity, escalation of care, length of hospital stay, lung functions, adverse events, and mortality. Results Nine studies (total participants=473) were included. Hospitalisation rate and the need for non-invasive ventilation were less among the intravenous magnesium sulfate group (mean difference (MD)=0.70, 95% CI 0.54 to 0.90, I 2 7%, n=115) and (risk ratio (RR)=0.17, 95% CI 0.15 to 0.54, p=0.003, n=143), respectively. Asthma severity scores (MD=−0.18, 95% CI −1.35 to 0.98, I 2 2%, n=115), length of hospital stay (MD=−78.86, 95% CI −200.37 to 42.66, I 2 99%, n=284) and the need for invasive ventilation (RR=0.35, 95% CI 0.11 to 1.17, I 2 0%, n=237) were similar. There was no difference in the Paediatric Intensive Care Unit (PICU) admission rate (p=0.43 n=61). Peak expiratory flow improved in the intravenous magnesium group (p<0.001, n=20). No serious adverse events were reported. Conclusion We found low-certainty evidence that intravenous magnesium sulfate results in a lower hospitalisation rate and less need for non-invasive ventilation. Asthma scores, PICU admission, invasive ventilation and length of hospital stay were similar. While the evidence base is weak, the favourable safety profile suggests that intravenous magnesium sulfate can be considered a treatment for asthma exacerbations. PROSPERO registration number CRD42023405261.