Modest benefit of inhaled magnesium sulfate for acute asthma in the emergency department

SOURCE
Knightly R, Milan SJ, Hughes R, et al.(2017). Inhaled magnesium sulfate in the treatmentof acute asthma. Cochrane Database SystRev 11:CD003898

CONTEXT
Acute asthma is a reason for frequent use of Emergency Department (ED). Despite effective therapies, some crises remain difficult to control. Magnesium sulfate (MgSO4) works by increasing the response of beta-receptors to beta-2-mimetics as well as by a direct bronchodilator effect. Its efficacywhen administered intravenously has been demonstrated, however its efficiency by nebulization needs to be evaluated.

CLINICAL QUESTION
Is MgSO4 administered by inhalation, combined or not with beta-2-mimetics or ipratropium, effective and safe in the ED for acute asthma?

BOTTOM LINE

MgSO4+ beta-2-mimetic + ipratropium versus beta-2-mimetic + ipratropium

The addition of MgSO4 by inhalation to a combined treatment of beta-2-mimetic and ipratropium improves pulmonary function. The decrease in the number of hospitalizations is not significant. There is no difference between the two groups in terms of clinical severity score evolution, functional physiological signs or adverse events. Only one study showed the efficacy of inhaled MgSO4 in children with severe or rapidly progressive asthma.

Beta-2-mimetic + MgSO4 versus beta-2-mimetic + placebo.

The combination of MgSO4 and beta-2-mimetic by inhalation compared to beta-2-mimetic does not show any significant difference in pulmonary function and hospitalization rates in either adults or children. The physiological functional signs are unchanged and the adverse reactions appear similar.

MgSO4 versus beta-2-mimetic

The data are not sufficient to perform a meta-analysis.

CAVEAT
Pulmonary function test analysis as a primary endpoint is not usual, as it is not always correlated to symptoms, quality of life or asthma control. Co-treatments with corticosteroids/ipratropium vary according to the studies, before or after nebulization of MgSO4, without precision on timing and doses. There is significant heterogeneity which makes the different comparisons difficult. Recent studies are rather of good quality with a low risk of bias. These do not show any significant benefits from the addition of nebulized MgSO4 in asthma.

AUTHOR INFORMATION

Julie DUMOUCHEL
Centre Hospitalo-Universitaire de TOURS
Tours, France
dumouchel.julie76@yahoo.fr

Daniel MEYRAN
Bataillon de Marins Pompiers de Marseille, groupement santé,
Marseille, France
daniel.meyran@me.com

Tanveer Ahmed YADGIR
Fatima College of Health Sciences
Al Ain, United Arab Emirates
drtanveer2008@gmail.com