Pilot Study of Magnesium Infusions in Pediatric Asthma

Inclusion Criteria: * Age 2 years 0 days up to 20 years 364 days * Clinical diagnosis of asthma including both of the following: * Attending physician's primary working diagnosis is status asthmaticus * Results of a modified International Study of Asthma and Allergies in Children (ISAAC) diagnostic questionnaire consistent with an asthma diagnosis * Planned PICU admission for moderate-to-severe asthma exacerbation persisting despite standard first-tier therapy (systemic corticosteroids and at least a one-hour treatment with nebulized albuterol/ipratroprium or equivalent) as evidenced by an asthma score of 7 or greater * IV access or equivalent * Ability to understand and give informed consent/assent in English Exclusion Criteria: * Prior enrollment in this study * Prior adverse reactions to magnesium * Use of systemic corticosteroids or magnesium in preceding 2 weeks, or administered at a transferring facility more than 3 hours prior to enrollment * Admission for inpatient asthma care in preceding 2 weeks * Hemodynamic instability, impending respiratory failure or intubation * Inability in children age 7 years or older to give assent due to a developmental delay or altered mental status * Significant renal or cardiac disease * Sickle cell anemia * Significant, active non-asthma pulmonary disease