Ipratropium bromide is a quaternary
anticholinergic bronchodilator that is commonly used to treat
obstructive lung disease. Although
ipratropium is not usually employed as a first-line
bronchodilator to treat chronic
asthma, it has been used extensively in hospital emergency departments as adjunctive
therapy for the
emergency treatment of acute
asthma exacerbation. This review will summarize the physiological actions of
ipratropium and the rationale for its use as an
anticholinergic bronchodilator. Evidence available from randomized trials and from two meta-analyses is summarized to determine whether the addition of inhaled
ipratropium to inhaled beta2-agonist
therapy is effective in the treatment of acute
asthma exacerbation in children and adults. Published reports of randomized, controlled trials assessing the use of
ipratropium and concurrent beta2-agonists in adult acute
asthma exacerbation were identified by a search of electronic databases, as well as by hand searching. Data from 10 studies of adult asthmatics, reporting on a total of 1377 patients, were pooled in a meta-analysis using a weighted-average method. Use of nebulized
ipratropium/beta2-agonist combination
therapy was associated with a pooled 7.3% improvement in forced expiratory volume in 1 sec [95% confidence interval (CI), 3.8-10.9%] and a 22.1% improvement in peak expiratory flow (95% CI, 11.0-33.2%) compared with patients who received beta2-agonist without
ipratropium. For the three trials in adults reporting hospital admission data (n = 1064), adult patients receiving
ipratropium had a relative risk of hospitalization of 0.80 (95% CI, 0.61-1.06). Similarly, randomized controlled studies of pediatric
asthma exacerbation and a meta-analysis of pediatric
asthma patients suggest that
ipratropium added to beta2-agonists improves lung function and also decreases hospitalization rates, especially among children with severe exacerbations of
asthma. The adult and pediatric studies did not report any severe adverse effects attributable to
ipratropium when it was used in conjunction with beta2-agonists. In conclusion, there is a modest statistical improvement in airflow obstruction when
ipratropium is used as an adjunctive to beta2-agonists for the treatment of acute
asthma exacerbation. In pediatric
asthma exacerbation, use of
ipratropium also appears to improve clinical outcomes; however, this has not been definitively established in adults. It would seem reasonable to recommend the use of combination
ipratropium/beta2-agonist
therapy in acute asthmatic exacerbation, since the addition of
ipratropium seems to provide physiological evidence of benefit without risk of adverse effects.