title: Longitudinal evaluation of compressor/nebulizer performance.
abstract: BACKGROUND
  Inhaled medications are the mainstay of treatment for maintenance of lung health in patients with cystic fibrosis (CF). Compressor/nebulizer units are used an average of 100-120 min/d by patients with CF. Each compressor/nebulizer has unique flow/pressure characteristics that affect particle size distribution and drug output rate. Few data are available regarding longitudinal performance of compressor/nebulizers. We hypothesized that their use over a 24-wk period under conditions similar to those of patients with CF would affect their performance.
  
  
  METHODS
  Four new units of compressor/reusable nebulizers from 3 brands (Pari Vios/Pari LC Plus, Pulmo-Aide 5650D/Viox, and Inspiration Elite/SideStream Plus) commonly used by patients with CF were tested. Compressor/nebulizers were operated for 1 h twice daily 5 d/wk for 24 wk. Compressor flow/pressure characteristics were measured every 6 wk. Maximal flow was recorded without and with the nebulizer (MF and MF/NEB, respectively). Pressure was recorded at zero flow (MP) and at MF/NEB (P/NEB). Particle size distribution, inhaled mass (IM), and IM in respirable range were evaluated at baseline and every 12 wk.
  
  
  RESULTS
  Vios had statistically significant declines in MP and P/NEB at each measurement compared with baseline (45.8 and 32.6 psi for MP and 16.7 and 14.3 psi for P/NEB at wk 0 and 24, respectively, P < .05), but other compressors did not. MF and MF/NEB were stable over time but significantly varied among brands. Vios had the greatest slope of flow/pressure relationship (Vios > Pulmo-Aide > Inspiration Elite). Two Vios units stopped working at wk 11 and 24, respectively. All compressors maintained baseline IM, IM in respirable range, and aerosol characteristics.
  
  
  CONCLUSIONS
  Long-term use of compressor/nebulizers in a regimen similar to that of patients with CF affected their performance. Pari Vios was the most affected brand, with declines in MP and P/NEB and 2 units that stopped working. Measurement of MF and MF/NEB could help identify compressors that are likely to fail.
authors.affiliation: Pulmonology Section, Department of Pediatrics, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, Arkansas.Department of Pediatrics. College of Medicine, Jordan University of Science and Technology, Irbid, Jordan.
authors.forename: Samah
authors.initials: S
authors.lastname: Awad
authors.affiliation: Department of Biostatistics, College of Public Health, University of Arkansas for Medical Sciences.
authors.forename: David K
authors.initials: DK
authors.lastname: Williams
authors.affiliation: Pediatric Aerosol Research Laboratory, Arkansas Children's Hospital Research Institute and the Pulmonology Section, Department of Pediatrics, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, Arkansas. BerlinskiAriel@uams.edu.
authors.forename: Ariel
authors.initials: A
authors.lastname: Berlinski
mesh_terms: D000280:Administration, Inhalation; D000336:Aerosols / Q000008:administration & dosage; D000420:Albuterol / Q000008:administration & dosage*; D001993:Bronchodilator Agents / Q000008:administration & dosage*; D003550:Cystic Fibrosis / Q000188:drug therapy; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006801:Humans; D008954:Models, Biological; D009330:Nebulizers and Vaporizers; D010316:Particle Size; D013997:Time Factors
chemical_list: D000336:Aerosols; D001993:Bronchodilator Agents; D000420:Albuterol
keywords: Compressor; aerosol; breathing simulation; cystic fibrosis; flow; nebulizer; particle size; pressure