Acute asthma
BMJ 2001; 323 doi: https://doi.org/10.1136/bmj.323.7317.841 (Published 13 October 2001) Cite this as: BMJ 2001;323:841
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EDITOR. In the Clinical review on interventions acute asthma "Extract
from Clinical Evidence”, Mark FitzGerald claims, that the effectiveness of
intravenous versus nebulised delivery of short acting beta2-agonists for
acute asthma remains unknown on basis of conflicting results from three
minor trials including a total number of 139 patients. (1)
In their recent Cochrane Library review "Intravenous beta2-agonists for
acute asthma in the emergency department" Travers et al. (2) states on
basis of results from 15 controlled trials including 584 patients that
"There is no evidence to support the use of IV beta2-agonists in patients
with severe acute asthma. These drugs should be given by inhalation. No
subgroups were identified in which the IV route should be considered."
I find it problematic that the paper published in BMJ (1) claiming
"Clinical Evidence" fail to mention the paper by Travers et al (2)
especially because these so called evidence based reviews are believed to
gain increasing impact on the future treatment of this common disease in
emergency departments.
And by the way its is thought-provoking that a paper examining the quality
of evidence based reviews suggests that reviews should be interpreted with
caution is published in the same issue of BMJ (3)
1. FitzGerald M. Acute asthma. Extracts from “Clinical evidence.”
Clinical review. BMJ 2001;323:841-5.
2. Travers A, Jones AP, Kelly K Camargo CA, Rowe BH. Intravenous beta2-
agonists for acute asthma in the emergency department (Cochrane review).
In: The Cochrane Library Issue 2, 2001. Oxford: Update Software.
3. Olsen O, Middleton P, Ezzo J, Gøtzsche P Hadhazy V, Herxheimer A,
Kleijnen J McIntosh H. Quality of Cochrane reviews: assessment of sample
from 1998. BMJ 2001;323:829-32.
Competing interests: No competing interests
Role of Magnesium sulfate in acute severe bronchial asthma
Intravenous magnesium sulfate has been reported to be a useful
adjunctive therapy in patients with acute asthma refractory to treatment
with inhaled beta-2-agonists.Benefits to IV magnesium sulfate have been
described in patients with normal serum magnesium levels, although
hypomagnesemia has been reported on up to 50% of patients with acute
asthma. Magnesium inhibits calcium channels of airway smooth muscle, thus
interfering in calcium-mediated smooth muscle contraction.
In general, magnesium sulfate is a safe and inexpensive drug,
particularly in the usual clinical dose of 2 g IV over 20 minutes, a dose
which increases serum levels to about twice the original level. However,
care should be taken to avoid magnesium intoxication, particularly in
patients with impaired renal function. Further data are needed to
establish the role of magnesium in severe asthma.
Competing interests: No competing interests