Intravenous magnesium therapy for moderate to severe pediatric asthma: results of a randomized, placebo-controlled trial. Intravenous magnesium for acute asthma: failure to decrease emergency treatment duration or need for hospitalization. Intravenous magnesium sulfate for the treatment of acute asthma in the emergency department. Intravenous magnesium sulfate in acute severe asthma not responding to conventional therapy. Intravenous magnesium sulfate as an adjunct in the treatment of acute asthma. Magnesium bolus or infusion fails to improve expiratory flow in acute asthma exacerbations.
To evaluate the efficacy of intravenous magnesium (IVMg) therapy for moderate to severe asthma exacerbations in pediatric patients.
                Randomized, double-blind, placebo-controlled, clinical trial.
                Urban pediatric emergency department.
                Thirty-one patients aged 6 to 18 years who were being treated for an acute asthma exacerbation with peak expiratory flow rate (PEFR) less than 60% of the predicted value after receiving three beta 2-adrenergic nebulizer treatments. Interventions: Magnesium sulfate infusion, 25 mg/kg (maximum, 2 gm), or equivolume saline solution for 20 minutes.
                Vital signs, O2 saturation by pulse oximetry, PEFR, forced vital capacity, forced expiratory volume at 1 second, and physical examination were serially recorded for 110 minutes, with serum magnesium concentrations measured before and after the 20-minute infusion. At 50 minutes the magnesium group had a significantly greater percentage of improvement from baseline in forced expiratory volume at 1 second (34% vs -1%; p = 0.05); this improvement was sustained and even greater at 110 minutes (75% vs 5%; p = 0.01). Results were similar for PEFR at 80 through 110 minutes (59% vs 20% at 110 minutes; p = 0.05) and for forced vital capacity (55% vs 8% at 80 minutes; p = 0.05). There were no significant intergroup differences in blood pressure at any point. Patients who received intravenous magnesium infusions were more likely to be discharged home from the emergency department than those who received placebo (4/15 vs 0/16; p = 0.03).
                Children treated with intravenous magnesium infusions for moderate to severe asthma had significantly greater improvement in short-term pulmonary function without any significant alteration in blood pressure, suggesting a role for this agent as an adjunct in the treatment of such patients. To evaluate the efficacy of routine early administration of i.v. magnesium to patients with acute asthma.
                Prospective, randomized clinical trial.
                Urban teaching hospital emergency department.
                One hundred twenty consecutive patients aged 18 to 65 years with acute asthma unresponsive to a single albuterol treatment.
                All patients received oxygen, 125 mg i.v. methylprednisolone, and hourly albuterol inhalation therapy. The study group also received 2 g i.v. magnesium sulfate infused over 20 minutes.
                Demographic and clinical characteristics were similar in both groups. Hospitalization was necessary in 13 of 58 patients who received magnesium (22%; 95% confidence intervals [CI], 13% to 32%) and 11 of 62 control patients (17%; 95% CI 10% to 26%; P = .523). Duration of ED treatment in discharged patients was 224 +/- 75 minutes in the magnesium group (95% CI, 208 to 240 minutes) and 228 +/- 90 minutes in the control group (95% CI, 209 to 247 minutes, P = .832). In addition, changes in peak expiratory flow were not statistically different.
                Routine early administration of IV magnesium in acute asthma does not alter treatment outcome. Conventional nebulized beta-agonist therapy has met with disappointing results in an increasing number of moderate to severe asthmatics who may be characterized as "poor responders." Thirty-eight patients suffering from acute exacerbations of moderate to severe asthma were treated in an emergency department with an intravenous infusion of saline placebo or 1.2 g of magnesium sulfate after conventional beta-agonist therapy failed to produce significant improvement in peak expiratory flow rate. Nineteen patients were randomized into each of two groups in a placebo-controlled, double-blind clinical trial. The treatment group demonstrated an increase in peak expiratory flow rate from 225 to 297 L/min as compared with 208 to 216 L/min seen in the placebo group. In addition, the number admitted vs discharged was significantly better for the treatment group (7 vs 12) than the placebo group (15 vs 4). Intravenous magnesium sulfate may represent a beneficial adjunct therapy in patients with moderate to severe asthma who show little improvement with beta-agonists. To evaluate the effectiveness of early administration of intravenous Magnesium sulfate (i.v. MgSO4) in children with acute severe asthma not responding to conventional therapy.
                Randomized double-blind, placebo-controlled trial.
                Pediatric emergency service of a large teaching hospital.
                47 children aged between 1-12 years with acute severe asthma showing inadequate or poor response to 3 doses of nebulized salbutamol given at an interval of 20 min each.
                The MgSO4 group received 0.2 ml/kg of 50% MgSO4 as intravenous (i.v.) infusion over 35 minutes and the placebo group received normal saline infusion in the same dose and at the same rate. MgSO4 solution and normal saline were coded and dispensed in identical containers. Decoding was done at the completion of the study. All the patients received oxygen, nebulized salbutamol, i.v. aminophylline and corticosteroids.
                MgSO4 group showed early and significant improvement as compared to placebo group in PEFR and SaO2 at 30 min and 1, 2, 3 and 7 hours after stopping the infusion (p ranging from < 0.05 to < 0.01). The clinical asthma score also showed significant improvement in the MgSO4 group 1, 2, 3 and 11 hours after stopping the infusion (p < 0.01).
                Addition of MgSO4 to conventional therapy helps in achieving earlier improvement in clinical signs and symptoms of asthma and PEFR in patients not responding to conventional therapy alone. This study was conducted to determine whether intravenous magnesium sulfate (MgSO4), when used as part of a standardized treatment protocol, can improve pulmonary function and decrease admission rate in patients presenting to the emergency department with exacerbations of asthma.
                In this randomized double-blind placebo-controlled study, patients with acute asthma were treated with inhaled beta-agonists at regular intervals and intravenous (IV) steroids. At 30 min after entry, patients received either 2 g IV MgSO4 or IV placebo. Patients were monitored for up to 4 h with regular measurements of pulmonary function. Patients who were discharged from the emergency department were contacted at 1 day and 7 days for follow-up.
                Emergency departments of a university-affiliated, voluntary hospital and municipal hospital.
                Asthmatics aged 18 to 65 years during acute exacerbation with FEV1 less than 75% predicted both before and after a single albuterol treatment.
                Patients were given 2 g of MgSO4 or placebo as an adjunct to standardized emergency department procedure for acute asthma.
                One hundred thirty-five patients were studied. Hospital admission rates were 35.3% for placebo-treated group and 25.4% for the magnesium-treated group (p = 0.21). FEV1 measured at 120 min was 56% predicted for the placebo-treated group and 55% predicted for the magnesium-treated group. (p = 0.92) For subgroup analysis, patients were divided into "severe" (baseline FEV1 < 25% predicted on presentation) or "moderate" (baseline FEV1, 25 to 75% predicted on presentation). For the severe group, admission rates were 78.6% (11/14) for the placebo-treated group and 33.3% (7/21) for the magnesium-treated group (p = 0.009). For the moderate patients, admission rates were 22.4% (11/49) for the placebo-treated group and 22.2% (10/25) for the magnesium-treated group (p = 0.98). There was no significant improvement in FEV1 in the moderate group for magnesium-treated patients. However, in the severe group, there was a significant improvement in FEV1 at 120 min and 240 min (p = 0.014 and 0.026, respectively).
                Intravenous MgSO4 decreased admission rate and improved FEV1 in patients with acute severe asthma but did not cause significant improvement in patients with moderate asthma. Intravenous magnesium sulfate improves objective measures of expiratory flow in patients with acute severe exacerbations of asthma.
                Randomized, double-blind, placebo-controlled trial.
                Urban emergency department.
                Forty-eight asthmatic patients aged 18 to 60 years with initial peak expiratory flow rate (PEFR) < 200 L/min who failed to double their initial PEFR after two standardized albuterol treatments.
                Subjects were randomized to three groups: a loading dose of magnesium sulfate, 2 g IV over 20 min followed by 2 g/h over 4 h (infusion), magnesium sulfate, 2 g over 20 min followed by placebo infusion (bolus), or placebo loading dose and infusion (placebo). All subjects received standardized aminophylline and steroid therapy.
                The PEFR and FEV1 were measured at the start of the loading dose, and 20, 50, 80, 140, 200, and 260 min later using a water-displacement spirometer. Changes from baseline were compared by one-way analysis of variance for repeated measures.
                Magnesium sulfate administration did not at any time significantly improve either FEV1 (F = 0.036, p = 0.96) or PEFR (F = 0.51, p = 0.61). This study had the power to detect a PEFR difference of 26 L/min and a FEV1 difference of 0.19 L between groups (beta = 0.20, alpha = 0.05 two-tailed significance).
                Use of IV magnesium sulfate in addition to standard therapy does not provide clinically meaningful improvement of objective measures of expiratory flow in patients with moderate to severe asthma exacerbations.