title: Assessing the effects of racemic and single-enantiomer albuterol on airway secretions in long-term intubated patients.
abstract: OBJECTIVE
  In vitro data suggest that the S-enantiomer of albuterol can induce mucociliary dysfunction. This clinical study assesses the clinical significance of standard doses of the S-enantiomer on airway secretions in long-term intubated patients by comparing a racemic formulation of albuterol, an R-enantiomer formulation, and normal saline solution.
  
  
  METHODS
  A placebo-controlled crossover study.
  
  
  METHODS
  Fourteen stable intubated patients with a median duration of intubation of 21 months and a median age of 72 years.
  
  
  METHODS
  Long-term ventilator unit in skilled nursing facility.
  
  
  METHODS
  Following a 2-week washout period during which regularly scheduled beta2-agonists were discontinued, tracheal aspirates were collected for 4 h/d for a 5-day period to establish baseline values, and the patients were then randomized in crossover manner to each of three nebulized treatments: normal saline solution, racemic albuterol, and R-albuterol. Each treatment was administered three times daily for 5 days, followed by a 2-day washout.
  
  
  METHODS
  Tracheal aspirates were analyzed for volume, sodium, chloride, bicarbonate, interleukin (IL)-8, IL-1beta, soluble intercellular adhesion molecule, and tumor necrosis factor-alpha.
  
  
  RESULTS
  There were no consistent significant differences among the three treatment periods either in terms of volume of secretions or in the concentrations of the electrolytes or the inflammatory indexes. However, all three treatments, including saline solution, were associated with increased secretion volume after the first dose, but this effect was not apparent on subsequent doses.
  
  
  CONCLUSIONS
  There were no significant differences between racemic albuterol and R-albuterol observed in this study for any of the parameters studied, suggesting that the S-enantiomer does not adversely affect airway secretions at recommended doses. In addition, the routine administration of nebulized beta(2)-sympathomimetic agonists to stable patients undergoing prolonged intubation, for the sole purpose of changing the volume and composition of secretions of airway secretions, is not supported by the results of this study.
authors.affiliation: Division of Pulmonary/Critical Care Medicine, Department of Medicine, HSC 17-040, Stony Brook University, Stony Brook, NY 11794-8172, USA. toriordan@notes.cc.sunysb.edu
authors.forename: Thomas G
authors.initials: TG
authors.lastname: O'Riordan
authors.forename: Wenyang
authors.initials: W
authors.lastname: Mao
authors.forename: Lucy B
authors.initials: LB
authors.lastname: Palmer
authors.forename: John J
authors.initials: JJ
authors.lastname: Chen
mesh_terms: D000280:Administration, Inhalation; D000318:Adrenergic beta-Agonists / Q000008:administration & dosage / Q000627:therapeutic use*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000420:Albuterol / Q000008:administration & dosage / Q000627:therapeutic use*; D001991:Bronchitis / Q000188:drug therapy* / Q000209:etiology / Q000378:metabolism; D018592:Cross-Over Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007442:Intubation, Intratracheal / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D009079:Mucociliary Clearance / Q000187:drug effects*; D009093:Mucus / Q000187:drug effects / Q000378:metabolism; D012121:Respiration, Artificial / Q000009:adverse effects; D013997:Time Factors; D014136:Tracheitis / Q000188:drug therapy* / Q000209:etiology / Q000378:metabolism; D016896:Treatment Outcome
chemical_list: D000318:Adrenergic beta-Agonists; D000420:Albuterol