Magnesium Sulphate in Acute Asthma
Date First Published:
July 23, 2005
Last Updated:
July 23, 2005
Report by:
Nicholas Arnold, Senior House Officer, Accident & Emergency (Norfolk & Norwich University Hospital)
Three-Part Question:
In [patients with acute severe asthma] does [a single dose if IV magnesium sulphate] help [improve bronchodilation]?
Clinical Scenario:
A young healthy adult with known asthma presents to the emergency department with an acute severe asthma attack. Following the BTS guidlines, you use salbutamol and ipratropium nebulisers and IV hydrocortisone, and wonder if a single dose if IV magnesium sulphate would be beneficial.
Search Strategy:
MEDLINE -
Search Details:
1996 to date (MEDL) using the Dialog Datastar interface. (ASTHMA.TI. AND INTRAVENOUS.TI. AND MAGNESIUM.TI. AND ADULT# AND LG=EN)
Outcome:
5 papers found of which 2 were irrelevant or of insufficient quality.
Relevant Paper(s):
| Study Title | Patient Group | Study type (level of evidence) | Outcomes | Key results | Study Weaknesses |
|---|---|---|---|---|---|
| Intravenous magnesium is ineffective in adult asthma, a randomized trial. Porter RS, Nester, Braitman LE, Geary U, Dalsey WC Mar-01 USA | Adult asthmatics between the ages of 18 and 55 presenting to the emergency department with a peak expiratory flow (PEF) of < 100 l/min or < 25% of predicted flow. | RCT | Improvement of PEFR | No improvement | Small Study |
| Reduction of admission rates to hospital | No improvement | ||||
| Intravenous magnesium sulfate in acute severe asthma. Boonyavorakul C, Thakkinstian A, Charoenpan P Sep-00 Thailand | Patients, aged 15-65 years with acute severe asthma attack, whose severity scores were greater than 4 | RCT | Improvement in severity score (in which PEFR was included) | No improvement | Very small trial |
| Reduction of admission rates to hospital | No improvement | ||||
| Intravenous magnesium sulfate treatment for acute asthma in the emergency department: a systematic review of the literature. Rowe BH, Bretzlaff JA, Bourdon C, Bota GW, Camargo CA Jr Sep-00 USA | Patients presenting with acute asthma and were treated with intravenous magnesium sulfate versus placebo | Systemic Review | Improvement of PEFR overall | No Improvement | |
| Improvement of PEFR in patients with severe asthma | Improved by 52 L/min (95% CI 27 to 78 | ||||
| Reduction of admission rates to hospital overall | No improvement | ||||
| Reduction of admission rates to hospital in aptients with severe asthma | Reduced, with odds ratio 0.10, 95% CI 0.04 to 0.27 |
Author Commentary:
The smaller studies do not demonstrate a signifiant improvement in either PEFR or reduction of hospital admission rates in moderate to severe asthmatics. However, if a distinction is made, it is demonstrated that intravenous magnesium sulphate does improve both PEFR and reduce hospital admission rates in the severe subgroup.
Bottom Line:
Intravenous magnesium sulfate appears to be improve PEFR compared to placebo in patients who present with acute severe asthma.
References:
- Porter RS, Nester, Braitman LE, Geary U, Dalsey WC. Intravenous magnesium is ineffective in adult asthma, a randomized trial.
- Boonyavorakul C, Thakkinstian A, Charoenpan P. Intravenous magnesium sulfate in acute severe asthma.
- Rowe BH, Bretzlaff JA, Bourdon C, Bota GW, Camargo CA Jr. Intravenous magnesium sulfate treatment for acute asthma in the emergency department: a systematic review of the literature.