Comparison of the Methacholine PC20 Between the Trudell Aeroeclipse* II Ban Nebulizer and the Wright Nebulizer
Condition: Asthma
Study type: Interventional

Summary: 
      This study will compare the methacholine PC20 of two different modern-delivery aerosol
      systems to determine if one may replace the other for use in clinical settings.
    

Detailed description: 
      Thirty three asthmatic subjects (>18 years, both sexes) who have stable asthma will be
      recruited to undergo methacholine challenges for a randomized, crossover, observational
      study. The objective of this study is to compare the methacholine PC20 of a modern delivery
      aerosol system, the Trudell AeroEclipse*II BAN nebulizer, to that of the current "gold
      standard", the English-Wright nebulizer. Subjects will inhale methacholine using both
      nebulizing systems on separate visits and the PC20 values will be compared. The results from
      these experiments will give us a better indication of whether the modern AeroEclipse* II BAN
      nebulizer might be sufficient to replace the current "gold standard" Wright nebulizer in
      clinical settings.

      Baseline Spirometry

      Baseline FEV1 and VC will be registered using an electronic spirometer meeting ATS
      requirements.

      Screening

      A medical history will be conducted by interview and asthma medications will be reviewed on
      this V1. Subjects will also undergo a Methacholine Challenge to determine their PC20 and
      therefore their eligibility into the study.

      Methacholine Challenge

      Challenges will be carried out after a minimum 8-hour washout of short-acting ß2-agonist.
      Subjects will perform methacholine challenges on 2 separate days at the same time of day, at
      least 24-hours apart and all within a 2-week period. At V2, subjects will be randomly
      assigned to use either the Wright nebulizer or the AeroEclipse*II BAN nebulizer. Methacholine
      inhalation from the Wright nebulizer will be performed as follows. Subjects are instructed to
      wear noseclips and to breathe normally from the mouthpiece during the 2-minute inhalation
      period. Subjects inhale normal saline, then doubling concentrations of methacholine for 2
      minutes each always starting at a dose of 0.03 mg/ml. Spirometry is measured with an
      electronic spirometer meeting ATS requirements. FEV1 is measured at 30 and 90 seconds after
      each inhalation and the highest FEV1 will be used to calculate the % fall from baseline.
      There is a 3 minute interval between the end of one inhalation dose and start of the next
      inhalation dose. The test is terminated when a fall in FEV1 of 20% of the baseline value
      occurs and the methacholine PC20 is calculated. The same protocol will be applied to
      methacholine inhalation using the AeroEclipse*II BAN nebulizer with the exception that the
      2-minute tidal breathing will be reduced to 20 seconds and the interval between the end of
      one inhalation dose and start of the next inhalation dose is 3 minutes and 40 seconds.
      Subjects will return to the lab on V3 to complete a methacholine challenge using the
      alternate nebulizer from the one used on V2.

      DATA ANALYSIS

      The methacholine PC20 values will be log-transformed before performing summary statistics.
      The PC20 values will be compared by paired t-test.
    

Intervention name(s): Methacholine Chloride; Trudell AeroEclipse*II BAN nebulizer; The English-Wright nebulizer
Intervention type(s): Drug; Device; Device
Intervention description(s): Choline ester that acts as a non-selective muscarinic receptor agonist in the parasympathetic nervous system
Low risk - commonly used to diagnose asthma; Generates aerosol after a certain inspiratory flow has been reached and then stops nebulization the moment the inspiratory flow falls below this value; Continuous-mode nebuilzer, designed to operate continuously with tidal breathing
Roxon Medi-Tech, Montreal, PQ, Canada
Intervention MeSH terms: Methacholine Chloride
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: None (Open Label)
Primary purpose: Treatment