Magnesium sulfate for treating exacerbations of acute asthma

1. In this review, parenteral magnesium sulfate was provided as 2 gm IV over 20 minutes to adults and 25-100 mg/kg IV to children.
2. Many patients who present for assessment and treatment to the emergency department with an asthmatic exacerbation may not benefit from early treatment with magnesium sulfate.
3. Patients with severe acute asthma appear to benefit in terms of pulmonary function improvements and reduced admissions. In this context, severe asthma is defined as peak expiratory flow rates of less than 25-30% predicted after initial beta2-agonist therapy in adults and/or non-response to treatment (adults and children), or peak expiratory flow rates of less 60% predicted (children).
4. A clinical approach may be to identify candidates for magnesium sulfate therapy among those patients who do not respond to initial beta2-agonists treatment.
5. Two studies examined the use of magnesium in children. Given the similarity of the findings in children, it should have the same indications in the adult population. Only one study examined its use in children aged less than six, but the numbers were small.
6. In addition to any magnesium intervention, standard acute asthma therapy must be administered to these patients early in the emergency department treatment.

 Intravenous beta2-agonists for acute asthma

The only recommendations for IV beta2-agonists use should be for those patients in whom inhaled therapy cannot be used, however there have been no tests of its efficacy in such situations.