Asthma: exacerbation: magnesium sulfate improves pulmonary function

Clinical bottom line (level 1a)

  1. Patients with an acute asthma exacerbation attending an emergency department who receive magnesium sulfate compared with placebo have an improvement in PEFR.
Alter et al: Annals of Emergency Medicine 2000; 36 : 191-197
Expires October 2003

The study

Systematic review of all randomised controlled trials of
  • Patients: acute bronchospasm in an emergency setting
  • Intervention: bolus iv magnesium sulfate (1.2 to 2 g) compared with placebo
  • Outcome: pulmonary function

    Articles found in all languages using Medline, Embase, 1966 to 1998 (search terms: detailed in text ) and searching bibliographies of retrieved articles. Abstracts of respiratory conferences were hand-searched for the previous 5 years and trialists and content experts were contacted to retrieve eligible articles.

    Selection criteria: by 1 reviewer: see above and below
    Appraisal criteria: by 2 reviewers: using Jadad criteria
    Articles excluded if:
    • magnesium not given intravenuously
    • case reports or case series


    9 studies found involving 859 patients
    Studies were not found to be heterogenious.

    The evidence

    • improvement in PEFR: summary effect size: 0.162 (95% CI: 0.028 to 0.297)

    Comments

    1. No severe adverse effects were reported.
    2. The systematic review failed to report any clinical endpoints.

    Citation

    1. Alter HJ, Koepsell TD, Hilty WM, et al: intravenous magnesium sulfate as an adjuvant in acute bronchospasm: a meta-analysis. Annals of Emergency Medicine 2000; 36 : 191-197
    Search Terms: from ACP Journal Club other articles noted
    Contributor: Chris Ball, October 2001
    Reviewer:

    Clinical Question.
    Patient acute asthma attending emergency department
    Intervention or Exposure iv magnesium sulfate
    Outcome PEFR