Article type
Year
Abstract
Objectives: Acute asthma in the emergency department (ED) is initially treated with systemic corticosteroids and inhaled beta-agonists (B2). Inhaled anticholinergics e.g. ipratropium bromide (IB) may offer additional bronchodilation. This systematic review was conducted to determine the effect (s) of adding inhaled IB and to compare to other published systematic reviews (SRs).
Methods: Comprehensive systematic searches were conducted of EMBASE, MEDLINE, CINAHL, and 20 leading respiratory care journals for individual studies and previously published SRs. Primary studies were included if ED patients with acute asthma were randomized to receive inhaled IB+B2 versus B2 alone. Two reviewers independently performed selection, methodological quality, and data extraction. For dichotomous variables we calculated relative risk (RR) with 95% confidence intervals (CI); for continuous variables we calculated weighted (WMD) or standardized mean differences (SMD) with 95% CI.
Results: 263 articles were reviewed. Fifteen of 31 potentially relevant citations met inclusion criteria. Results are based on 1992 adults (63% female), age 40.5 yr. SD 8.0) in trials between 1987-2000. Overall, inhaled IB+B2 significantly reduced admission to hospital (RR = 0.68; 95% CI: 0.55 to 0.84). The effect size for single or multiple dose protocols showed significant change in pulmonary function at < 1 hour when compared with B2 alone (SMD single = 0.32; 95% CI: 0.18 to 0.46; SMD multiple = 0.78; 95% CI: 0.53 to 1.03).This effect continued 2 hrs and beyond. There was a trend to greater response in the more severe sub-group on multple dose IB regimens (FEV1 < 1L or PEFR < 140 L/min) SMD severe = 0.47; 95% CI: 0.10 to 0.85; SMD moderate = 0.30; 95% CI: 0.18 to 0.41. There were no differences in other clinical responses and no serious adverse events were reported. Three similar published SRs were identified, using different methoids and included studies; they arrived at somewhat more positive outcomes.
Conclusions: Adding inhaled IB to a beta-agonist early in ED treatment of acute asthma appears to provide moderate benefits to the patient in improved lung function but significantly reduces risk of hospital admission by 32%. The Cochrane review suggests more modest effect than other published reports.
Methods: Comprehensive systematic searches were conducted of EMBASE, MEDLINE, CINAHL, and 20 leading respiratory care journals for individual studies and previously published SRs. Primary studies were included if ED patients with acute asthma were randomized to receive inhaled IB+B2 versus B2 alone. Two reviewers independently performed selection, methodological quality, and data extraction. For dichotomous variables we calculated relative risk (RR) with 95% confidence intervals (CI); for continuous variables we calculated weighted (WMD) or standardized mean differences (SMD) with 95% CI.
Results: 263 articles were reviewed. Fifteen of 31 potentially relevant citations met inclusion criteria. Results are based on 1992 adults (63% female), age 40.5 yr. SD 8.0) in trials between 1987-2000. Overall, inhaled IB+B2 significantly reduced admission to hospital (RR = 0.68; 95% CI: 0.55 to 0.84). The effect size for single or multiple dose protocols showed significant change in pulmonary function at < 1 hour when compared with B2 alone (SMD single = 0.32; 95% CI: 0.18 to 0.46; SMD multiple = 0.78; 95% CI: 0.53 to 1.03).This effect continued 2 hrs and beyond. There was a trend to greater response in the more severe sub-group on multple dose IB regimens (FEV1 < 1L or PEFR < 140 L/min) SMD severe = 0.47; 95% CI: 0.10 to 0.85; SMD moderate = 0.30; 95% CI: 0.18 to 0.41. There were no differences in other clinical responses and no serious adverse events were reported. Three similar published SRs were identified, using different methoids and included studies; they arrived at somewhat more positive outcomes.
Conclusions: Adding inhaled IB to a beta-agonist early in ED treatment of acute asthma appears to provide moderate benefits to the patient in improved lung function but significantly reduces risk of hospital admission by 32%. The Cochrane review suggests more modest effect than other published reports.