Magnesium in acute pediatric asthma in the emergency department (MAGICIAN)-A multicentre randomized controlled clinical trial protocol.

BACKGROUND

While guidelines recommend intravenous magnesium (IVMg) for refractory pediatric acute asthma, evidence for benefit is scant and disparate. IVMg therapy is resource-intensive and can cause hypotension. To determine if IVMg alters the exacerbation course, it must be given early, and the clinical effect measured at the peak effect of routine co-interventions.

PRIMARY AIM: In children with acute asthma remaining in moderate-severe respiratory distress after initial ED therapy, to determine if early IVMg therapy is associated with a significantly greater improvement in respiratory distress at 2 hours after starting IVMg, compared to placebo.

HYPOTHESIS: IVMg will yield significantly greater Pediatric Respiratory Assessment Measure (PRAM) improvement of ≥1.0 point than placebo.

STUDY

DESIGN

A randomized double-blind placebo-controlled trial in 6 Canadian pediatric EDs of otherwise healthy children 2-17 years old with acute asthma and PRAM ≥5 after initial 1 hour therapy with systemic corticosteroids and 3 inhaled salbutamol ± ipratropium treatments.

INTERVENTION: IVMg sulfate (75 mg/kg, max 2.5 g) or normal saline placebo over 30 minutes.

PRIMARY OUTCOME: PRAM 2 hours post-intervention start. Secondary: PRAM ≤3 at 2 hours; change in PRAM and vital signs over 3 hours; hospitalization; asthma re-visits by 72 hours.

SAMPLE SIZE: With 192 patients, a two-sided test and alpha 0.05 have 80% power to achieve statistical significance if IVMg yields a difference in PRAM changes ≥1.0 point between groups.

PRIMARY ANALYSIS: Student's t test comparing a difference in PRAM changes between groups.

EXPECTED OUTCOMES: This trial will clarify if there is an incremental clinical benefit of IVMg in pediatric refractory asthma. A positive result will establish a proven routine standard of care for this indication; a negative result will lead to de-implementation of IVMg which may also lead to cost savings.

STATUS: Enrolling at SickKids and McMaster, start of other sites pending. No results generated yet.

STUDY TITLE: Magnesium Trial in Acute Asthma in Emergency Department.