title: Nebulizer delivery of tobramycin to the lower respiratory tract.
abstract: We characterized a tobramycin aerosol generated by five nebulizers: Micron One, Pulmosonic, Pulmo-Aide, DeVilbiss Model 65, and UltraNeb 100 by particle size and drug concentration. The Micron One nebulizer did not produce a recoverable aerosol, while the Pulmosonic had a minimal output; therefore three machines were examined for their ability to deliver tobramycin to the lower respiratory tract of patients with cystic fibrosis (CF). The DeVilbiss 65 had the greatest output: with air as the carrier gas it produced an aerosol with > 60% of the particles having a mean mass aerodynamic diameter (MMAD) of > 5.5 microns. Using helox shifted the MMAD so that > 65% of the particles were < 5.5 microns. Increasing the power in the DeVilbiss 65 increased the output of particles > 9.2 microns, without a change in the particles < 3.3 microns. With air as the carrier gas the Pulmo-Aide and the UltraNeb 100 produced an aerosol with > 60% particles, < 3.3 microns MMAD. Using helox the UltraNeb 100 increased the amount of aerosol with a < 3.3 microns MMAD to 98%. Tobramycin delivery to the lower respiratory tract with the Pulmo-Aide and UltraNeb 100 was compared using air or helox by measuring sputum drug concentration. Pulmo-Aide failed to produce detectable tobramycin in sputum in 2 out of 9 patients with CF. With the UltraNeb 100, all patients had measurable sputum tobramycin immediately after administration (range, 16.2-3385 micrograms/g), but no statistically significant difference was found when using either compressed air, helox, or ambient air.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Cystic Fibrosis Research Cener, Children's Hospital and Medical Center, Seattle, WA 98105.
authors.forename: A
authors.initials: A
authors.lastname: Weber
authors.forename: A
authors.initials: A
authors.lastname: Smith
authors.forename: J
authors.initials: J
authors.lastname: Williams-Warren
authors.forename: B
authors.initials: B
authors.lastname: Ramsey
authors.forename: D S
authors.initials: DS
authors.lastname: Covert
mesh_terms: D000293:Adolescent; D000328:Adult; D000336:Aerosols; D002648:Child; D003550:Cystic Fibrosis / Q000378:metabolism; D004337:Drug Carriers; D005260:Female; D005740:Gases; D006801:Humans; D008297:Male; D009330:Nebulizers and Vaporizers; D010316:Particle Size; D012137:Respiratory System / Q000378:metabolism*; D013183:Sputum / Q000378:metabolism; D014031:Tobramycin / Q000008:administration & dosage* / Q000493:pharmacokinetics
chemical_list: D000336:Aerosols; D004337:Drug Carriers; D005740:Gases; D014031:Tobramycin