title: Diurnal expiratory flow after inhalation of Freons and fenoterol in childhood asthma.
abstract: Eighteen children aged 8 to 14 years with bronchial asthma were studied with respect to the diurnal variation in pulmonary expiratory flow and the influence on it of inhalation of Freons and of a beta 2-receptor stimulator, fenoterol. A double-blind technique and randomized order of the different conditions were used. Dynamic spirometric tests were performed every hour from 8 A.M. to 4 P.M. The low expiratory flow in the morning increased during the day and influenced the estimated duration of the beta 2-receptor stimulator. This must be taken into consideration when evaluating the long-term effect of bronchodilator drugs. The Freons acted as irritants and lowered the expiratory flow during the first 2 hr after inhalation. However, this impairment of lung function does not seem to be of any clinical importance when freons are used as propellants for potent beta 2-receptor stimulators such as fenoterol.
mesh_terms: D000293:Adolescent; D000336:Aerosols; D001249:Asthma / Q000188:drug therapy* / Q000503:physiopathology; D002648:Child; D005617:Chlorofluorocarbons, Methane / Q000008:administration & dosage / Q000009:adverse effects*; D002940:Circadian Rhythm; D004311:Double-Blind Method; D004983:Ethanolamines / Q000008:administration & dosage*; D005260:Female; D005280:Fenoterol / Q000008:administration & dosage*; D005540:Forced Expiratory Flow Rates; D006801:Humans; D008168:Lung / Q000187:drug effects* / Q000503:physiopathology; D008297:Male
chemical_list: D000336:Aerosols; D005617:Chlorofluorocarbons, Methane; D004983:Ethanolamines; D005280:Fenoterol