Blitz M, Blitz S, Beasely R, Diner B M, Hughes R, Knopp J A, Rowe B H
University of Alberta, Division of General Surgery, W.C. Mackenzie Centre, 8440-112 Street, Edmonton, Alberta, Canada T6G 2B7.
Cochrane Database Syst Rev. 2005 Oct 19(4):CD003898. doi: 10.1002/14651858.CD003898.pub4.
Asthma exacerbations can be frequent and range in severity from relatively mild to status asthmaticus. The use of magnesium sulfate (MgSO4) is one of numerous treatment options available during acute exacerbations. While the efficacy of intravenous MgSO4 has been demonstrated, little is known about inhaled MgSO4.
To examine the efficacy of inhaled MgSO4 in the treatment asthma exacerbations.
Randomised controlled trials were identified from the Cochrane Airways Group "Asthma and Wheez*" register. These trials were supplemented with trials found in the reference list of published studies, studies found using extensive electronic search techniques, as well as a review of the gray literature and conference proceedings.
Randomised (or pseudo-randomised) controlled trials were eligible for inclusion. Studies were included if patients were treated with nebulised MgSO4 alone or in combination with beta2-agonist and where compared to beta2-agonist alone or inactive control.
Trial selection, data extraction and methodological quality were assessed by two independent reviewers. Efforts were made to collect missing data from authors. Results from fixed effects models are presented as standardized mean differences (SMD) for pulmonary functions and relative risks (RR) for hospital admission; both are displayed with their 95% confidence intervals (95% CI).
Six trials involving 296 patients were included. Four studies compared nebulised MgSO4 with beta2-agonist to beta2-agonist and two studies compared MgSO4 to beta2-agonist alone. Three studies enrolled only adults and 2 enrolled exclusively pediatric patients; three of the studies enrolled severe asthmatics. Overall, there was a non significant improvement in pulmonary function between patients whose treatments included nebulised MgSO4 in addition to beta2-agonist (SMD: 0.23; 95% CI: -0.03 to 0.50; 4 studies). Hospitalizations were similar between the groups (RR: 0.69; 95% CI: 0.42 to 1.12; 3 studies). Subgroup analyses did not demonstrate significant differences in lung function improvement between adults and children, but in severe asthmatics the lung function difference was significant (SMD: 0.55; 95% CI: 0.12 to 0.98). Conclusions regarding treatment with nebulised MgSO4 alone are difficult to draw due to lack of studies in this area.
AUTHORS' CONCLUSIONS: Nebulised inhaled magnesium sulfate in addition to beta2-agonist in the treatment of an acute asthma exacerbation, appears to have benefits with respect to improved pulmonary function in patients with severe asthma and there is a trend towards benefit in hospital admission. Heterogeneity between trials included in this review precludes a more definitive conclusion.
哮喘急性发作可能频繁发生，严重程度从相对轻微到哮喘持续状态不等。硫酸镁（MgSO4）的使用是急性发作期间众多可用治疗选择之一。虽然静脉注射MgSO4的疗效已得到证实，但关于吸入MgSO4的了解却很少。
探讨吸入MgSO4治疗哮喘急性发作的疗效。
从Cochrane Airways Group的“Asthma and Wheez*”登记册中识别随机对照试验。这些试验通过已发表研究的参考文献列表中找到的试验、使用广泛电子搜索技术找到的研究以及灰色文献和会议记录的综述进行补充。
随机（或准随机）对照试验符合纳入条件。如果患者单独接受雾化MgSO4治疗或与β2激动剂联合治疗，并与单独使用β2激动剂或无活性对照进行比较，则纳入研究。
由两名独立评审员评估试验选择、数据提取和方法学质量。努力从作者处收集缺失数据。固定效应模型的结果以肺功能的标准化平均差（SMD）和住院的相对风险（RR）表示；两者均显示其95%置信区间（95%CI）。
纳入了6项涉及296名患者的试验。4项研究比较了雾化MgSO4与β2激动剂联合使用与单独使用β2激动剂，2项研究比较了MgSO4与单独使用β2激动剂。3项研究仅纳入成人，2项研究仅纳入儿科患者；其中3项研究纳入了重度哮喘患者。总体而言，除β2激动剂外还接受雾化MgSO4治疗的患者的肺功能有非显著性改善（SMD：0.23；95%CI：-0.03至0.50；4项研究）。两组之间的住院率相似（RR：0.69；95%CI：0.42至1.12；3项研究）。亚组分析未显示成人和儿童在肺功能改善方面有显著差异，但在重度哮喘患者中肺功能差异显著（SMD：0.55；95%CI：0.12至0.98）。由于该领域缺乏研究，难以得出关于单独使用雾化MgSO4治疗的结论。
在治疗急性哮喘发作时，除β2激动剂外雾化吸入硫酸镁似乎对改善重度哮喘患者的肺功能有益，并且在住院方面有获益趋势。本综述中纳入的试验之间的异质性妨碍了得出更明确的结论。
