URG-L: Encore le Mg !!

[J Levasseur]

Une de plus…   Jean L   IV Magnesium Sulfate in the Treatment of Acute Severe Asthma* A Multicenter Randomized Controlled Trial Robert A. Silverman, MD; Harold Osborn, MD; Jeffrey Runge, MD; E. John Gallagher, MD; William Chiang, MD; James Feldman, MD; Theodore Gaeta, DO; Katherine Freeman, DrPH; Bruce Levin, PhD; Noel Mancherje, MD and Steven Scharf, MD, PhD for the Acute Asthma/Magnesium Study Group * From the Department of Emergency Medicine (Drs. Silverman and Mancherje), Long Island Jewish Medical Center, New Hyde Park, NY; the Department of Emergency Medicine (Dr. Osborn), Bronx Lebanon Medical Center, Bronx, NY; the National Highway Traffic Safety Administration (Dr. Runge), US Department of Transportation, Washington, DC; Montefiore Medical Center (Dr. Gallagher), Bronx, NY; the Department of Emergency Medicine (Dr. Chiang), Bellevue Hospital Medical Center, New York, NY; the Department of Emergency Medicine (Dr. Feldman), Boston City Medical Center, Boston, MA; the Department of Emergency Medicine (Dr. Gaeta), the New York Methodist Hospital, Brooklyn, NY; the Department of Biostatistics (Dr. Freeman), Montefiore Medical Center, Bronx, NY; the Department of Biostatistics and Epidemiology (Dr. Levin), Columbia University School of Public Health, New York, NY; and the Division of Pulmonary and Critical Care Medicine (Dr. Scharf), Department of Medicine, Long Island Jewish Medical Center, New Hyde Park, NY. Dr. Osborn is currently with the Department of Emergency Medicine, Bronx Lebanon Medical Center, Bronx, NY. Dr. Runge is currently with the National Highway Traffic Safety Administration, United States Department of Transportation, Washington, DC. Dr. Gallagher is currently with the Department of Emergency Medicine, Albert Einstein College of Medicine, Bronx, NY. Dr. Gaeta is currently with the Department of Emergency Medicine, New York Methodist Hospital, Brooklyn, NY. A list of investigators can be found in the Appendix. Correspondence to: Robert Silverman, MD, Department of Emergency Medicine, Long Island Jewish Medical Center, New Hyde Park, NY 11042; e-mail: [EMAIL PROTECTED] Background: Studies of IV magnesium sulfate as a treatment for acute asthma have had mixed results, with some data suggesting a benefit for acute severe asthma, but not for mild-to-moderate asthma. In a multicenter cohort, this study tests the hypothesis that administration of magnesium sulfate improves pulmonary function in patients with acute severe asthma. Design: Placebo-controlled, double-blind, randomized clinical trial. Setting: Emergency departments (EDs) of eight hospitals. Patients: Patients aged 18 to 60 years presenting with acute asthma and FEV1 30% predicted on arrival to the ED. Intervention: All patients received nebulized albuterol at regular intervals and IV methylprednisolone. Two grams of IV magnesium sulfate or placebo were administered 30 min after ED arrival. The primary efficacy end point was FEV1 at 240 min, and the data analysis was intent to treat. Results: Two hundred forty-eight patients were included, and the mean FEV1 on ED arrival was 22.9% predicted. At 240 min, patients receiving magnesium had a mean FEV1 of 48.2% predicted, compared to 43.5% predicted in the placebo-treated group (mean difference, 4.7%; 95% confidence interval [CI], 0.29 to 9.3%; p = 0.045). A regression model confirmed the effect of magnesium compared to placebo was greater in patients with a lower initial FEV1 (p < 0.05). If the initial FEV1 was < 25% predicted, the final FEV1 was 45.3% predicted in the magnesium-treated group and 35.6% predicted in the placebo-treated group (mean difference, 9.7%; 95% CI, 4.0 to 15.3%; p = 0.001). If the initial FEV was 25% predicted, magnesium administration was not beneficial; the final FEV1 was 51.1% predicted in the magnesium-treated group and 53.9% predicted in the placebo-treated group (mean difference, - 2.9%, 95% CI, - 9.4 to 3.7; p = not significant). Overall, the use of magnesium sulfate did not improve hospital admission rates. Conclusion: Administration of 2 g of IV magnesium sulfate improves pulmonary function when used as an adjunct to standard therapy in patients with very severe, acute asthma.