title: The impact of inspiratory effort on inspiratory flow through Turbuhaler in asthmatic patients.
abstract: To investigate the impact of the inhalation effort on the peak inspiratory flow through Turbuhaler, 100 asthmatics having a wide range of asthma severity (baseline forced expiratory volume in one second 28-127% of predicted normal) were studied. Each patient inhaled through four modifications of empty Turbuhaler inhalers, using first a "deep" inhalation and then a "forceful and deep" inhalation manoeuvre. Peak inspiratory flow increased by an average of 20% using a "forceful and deep" as compared to a "deep" inhalation, with a markedly higher increase for the patients who had a low peak inspiratory flow using the deep inhalation. Virtually all patients (97-100%) attained a peak inspiratory flow > or = 40 L x min(-1) after a "forceful and deep" inhalation. This study demonstrates that instructing the patient to take a "forceful and deep" inhalation optimizes the use of Turbuhaler. Irrespective of asthma severity, the vast majority of patients could attain a sufficiently high peak inspiratory flow with a "forceful and deep" inhalation.
authors.affiliation: Dept of Medicine, University Hospital of Lund, Sweden.
authors.forename: G
authors.initials: G
authors.lastname: Persson
authors.forename: B
authors.initials: B
authors.lastname: Olsson
authors.forename: S
authors.initials: S
authors.lastname: Soliman
mesh_terms: D000280:Administration, Inhalation; D000328:Adult; D001249:Asthma / Q000188:drug therapy / Q000503:physiopathology*; D005260:Female; D006801:Humans; D001239:Inhalation / Q000502:physiology*; D008297:Male; D009330:Nebulizers and Vaporizers; D016037:Single-Blind Method