Effect of inhaled bronchodilators on inspiratory capacity and dyspnoea at rest in COPD

• Published in: The European respiratory journal Vol. 21; no. 1; pp. 86 - 94
• Main Authors: Di Marco, F, Milic-Emili, J, Boveri, B, Carlucci, P, Santus, P, Casanova, F, Cazzola, M, Centanni, S
• Format: Journal Article
• Language: English
• Published: Leeds Eur Respiratory Soc 01.01.2003; Maney
• Subjects: Administration, Inhalation; Adrenergic beta-Agonists - therapeutic use; Aged; Albuterol - analogs & derivatives; Albuterol - therapeutic use; Biological and medical sciences; Bronchodilator Agents - therapeutic use; Chronic obstructive pulmonary disease, asthma; Cross-Over Studies; Double-Blind Method; Dyspnea - drug therapy; Ethanolamines - therapeutic use; Female; Forced Expiratory Volume - drug effects; Formoterol Fumarate; Humans; Male; Medical sciences; Pneumology; Pulmonary Disease, Chronic Obstructive - drug therapy; Salmeterol Xinafoate; Scopolamine Derivatives - therapeutic use; Time Factors; Vital Capacity - drug effects; Human; Lung disease; Prognosis; Respiratory disease; Bronchodilator; Dynamic hyperinflation expiratory flow limitation formoterol oxitropium salbutamol salmeterol; Maximal expiratory volume per second; Inspiratory reserve volume; Inhalation; Chronic; Dyspnea; Bronchus disease; Obstructive pulmonary disease
• ISSN: 0903-1936; 1399-3003
• DOI: 10.1183/09031936.03.00020102

It has been shown that patients with chronic obstructive pulmonary disease (COPD) develop dynamic hyperinflation (DH), which contributes to dyspnoea and exercise intolerance. Formoterol, salmeterol and oxitropium have been recommended for maintenance therapy in COPD patients, but their effect on DH has only been assessed for salmeterol. The aim of the present study was to compare the acute effect of four inhaled bronchodilators (salbutamol, formoterol, salmeterol and oxitropium) and placebo on forced expiratory volume in one second, inspiratory capacity, forced vital capacity and dyspnoea in COPD patients. A cross-over, randomised, double-blind, placebo-controlled study was carried out on 20 COPD patients. Patients underwent pulmonary function testing and dyspnoea evaluation, in basal condition and 5, 15, 30, 60 and 120 min after bronchodilator or placebo administration. The results indicate that in chronic obstructive pulmonary disease patients with decreased baseline inspiratory capacity, there was a much greater increase of inspiratory capacity after bronchodilator administration, which correlated closely with the improvement of dyspnoea sensation at rest. For all bronchodilators used, inspiratory capacity reversibility should be tested at 30 min following the bronchodilator. On average, formoterol elicited the greatest increase in inspiratory capacity than the other bronchodilators used, though the difference was significant only with salmeterol and oxitropium. The potential advantage of formoterol needs to be tested in a larger patient population.