title: Testing of nebulizers for delivering magnesium sulfate to pediatric asthma patients in the emergency department.
abstract: BACKGROUND
  As the use of intravenous magnesium sulfate (MgSO(4)) for the treatment of refractory asthma is becoming more common, the incidence of MgSO(4)-related systemic hypotension is also rising. One option is to deliver MgSO(4) via aerosol, but compared to most inhaled medications, which are active in the microgram dose range, the MgSO(4) dose requirement is in the milligram range. This, along with inefficient aerosol delivery systems, may be the reason that some studies have found lack of efficacy with aerosol MgSO(4). In preparation for a multicenter study of inhaled MgSO(4) in asthmatic children 2-17 years old, we conducted an in vitro study to choose the best MgSO(4) nebulizer system that would be effective over the entire age range.
  
  
  METHODS
  We tested the Pari LC Star jet nebulizer, Omron MicroAir vibrating-mesh nebulizer, and the Aeroneb Go vibrating-mesh nebulizer with the Idehaler valve-less holding chamber. Aerosol delivery was via face mask.
  
  
  RESULTS
  The Pari LC Star had an appropriate particle size distribution but a very slow aerosol output rate. The Omron MicroAir had an even slower output rate and a larger particle size distribution, which would be inappropriate for smaller children. In vitro lung deposition with the Aeroneb Go with Idehaler was 16.0 ± 0.4 mg/min in older children and approximately a fifth of that in toddlers.
  
  
  CONCLUSIONS
  The Aeroneb Go with Idehaler was chosen for the multicenter clinical study.
authors.affiliation: Department of Physiology and Experimental Medicine, University of Toronto, Toronto, Ontario, Canada. allan.coates@sickkids.ca
authors.forename: Allan L
authors.initials: AL
authors.lastname: Coates
authors.forename: Kitty
authors.initials: K
authors.lastname: Leung
authors.forename: Laurent
authors.initials: L
authors.lastname: Vecellio
authors.forename: Suzanne
authors.initials: S
authors.lastname: Schuh
mesh_terms: D000280:Administration, Inhalation; D000293:Adolescent; D000336:Aerosols; D001249:Asthma / Q000188:drug therapy*; D001993:Bronchodilator Agents / Q000008:administration & dosage*; D002648:Child; D002675:Child, Preschool; D004636:Emergency Service, Hospital; D006801:Humans; D008278:Magnesium Sulfate / Q000008:administration & dosage*; D008954:Models, Biological; D009330:Nebulizers and Vaporizers
chemical_list: D000336:Aerosols; D001993:Bronchodilator Agents; D008278:Magnesium Sulfate