title: Differences in inhaled fluticasone bioavailability between holding chambers in children with asthma.
abstract: OBJECTIVE
  To determine if differences between holding chambers in previous in vitro aerosol studies would agree with the bioavailability of inhaled fluticasone propionate between the same holding chambers in children with asthma.
  
  
  METHODS
  Double-blind, randomized, crossover study
  
  
  METHODS
  University of Florida Clinical Research Center.
  
  
  METHODS
  Eight children (aged 5-9 yrs) with stable asthma.
  
  
  METHODS
  Under observation, the children inhaled two 110-microg puffs of fluticasone twice/day through the InspirEase or E-Z Spacer holding chamber.
  
  
  RESULTS
  Blood samples were collected at baseline and then at 0.5, 1, 1.5, 2, 4, and 6 hours after the last dose of fluticasone. Primary outcome measures were peak fluticasone steady-state plasma concentration (Cmax) and area under the fluticasone plasma concentration-time curve from 0-6 hours (AUC0-6). The fluticasone plasma concentrations were determined by high-performance liquid chromatography-mass spectrometric assay. Mean +/- SD Cmax from InspirEase (245 +/- 77 pg/ml) was 18% higher than that after E-Z Spacer (199 +/- 58 pg/ml, p < 0.05). Mean +/- SD AUC0-6 from InspirEase (1103 +/- 305 pg x hr(-1) x ml(-1) was 22% higher than that delivered from E-Z Spacer (863 +/- 258 pg x hr(-1) x ml(-1), p = 0.06).
  
  
  CONCLUSIONS
  Differences in inhaled fluticasone bioavailability between these holding chambers in children with asthma corroborate differences reported in earlier in vitro aerosol studies.
authors.affiliation: Department of Pharmacy Practice, College of Pharmacy, University of Florida, Gainesville 32610-0486, USA.
authors.forename: Judy
authors.initials: J
authors.lastname: Liang
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Asmus
authors.forename: Günther
authors.initials: G
authors.lastname: Hochhaus
authors.forename: Sarah
authors.initials: S
authors.lastname: Chesrown
authors.forename: Leslie
authors.initials: L
authors.lastname: Hendeles
mesh_terms: D000280:Administration, Inhalation; D000336:Aerosols; D000730:Androstadienes / Q000008:administration & dosage / Q000097:blood*; D019540:Area Under Curve; D001249:Asthma / Q000097:blood*; D001682:Biological Availability; D001993:Bronchodilator Agents / Q000008:administration & dosage / Q000097:blood*; D002648:Child; D002675:Child, Preschool; D018592:Cross-Over Studies; D004311:Double-Blind Method; D000068298:Fluticasone; D006801:Humans; D008297:Male; D009330:Nebulizers and Vaporizers
chemical_list: D000336:Aerosols; D000730:Androstadienes; D001993:Bronchodilator Agents; D000068298:Fluticasone