Document Detail

Combined physiological effects of bronchodilators and hyperoxia on exertional dyspnoea in normoxic COPD.
MedLine Citation:
PMID:  16467067     Owner:  NLM     Status:  MEDLINE    
BACKGROUND: Studies examining the physiological interactions of oxygen (O(2)) and bronchodilators (BD) during exercise in chronic obstructive pulmonary disease (COPD) should provide new insights into mechanisms of exercise intolerance. We examined the effects of O(2) and BD, alone and in combination, on dyspnoea, ventilation (e), breathing pattern, operating lung volumes, and exercise endurance.
METHODS: In a randomised, double blind, crossover study, 16 patients with COPD (mean (SE) FEV(1) 43(3)% predicted) performed pulmonary function tests and an incremental exercise test, then completed four visits in which they received either nebulised BD (ipratropium 0.5 mg + salbutamol 2.5 mg) or placebo (PL) with either 50% O(2) or room air (RA). After 90-105 minutes the patients performed pulmonary function tests, then breathed RA or O(2) during symptom limited constant load exercise at 75% peak work rate.
RESULTS: With BD the mean (SE) increase in inspiratory capacity (IC) was 0.3 (0.1) l (p<0.05) at rest and during exercise, permitting greater tidal volume (Vt) expansion during exercise and a greater peak e. With O(2), e decreased during exercise as a result of decreased breathing frequency (F), with no significant change in IC. During exercise with BD+O(2), IC and Vt increased, F decreased, and e did not change. Dyspnoea decreased with all interventions at a standardised time during exercise compared with PL+RA (p<0.05). Endurance time was significantly (p<0.05) greater with BD+O(2) (10.4 (1.6) min) than with O(2) (8.5 (1.4) min), BD (7.1 (1.3) min) and PL+RA (5.4 (0.9) min).
CONCLUSION: By combining the benefits of BD (reduced hyperinflation) and O(2) (reduced ventilatory drive), additive effects on exercise endurance were observed in patients with normoxic COPD.
M M Peters; K A Webb; D E O'Donnell
Related Documents :
20463947 - Impact of bronchodilator therapy on exercise tolerance in copd.
9727787 - Emotional status does not alter exercise tolerance in patients with chronic obstructive...
12093627 - Effect of chest wall vibration on dyspnea during exercise in chronic obstructive pulmon...
24453527 - Inspiratory muscle fatigue following moderate-intensity exercise in the heat.
3030607 - Dynamic exercise-induced increase in lymphocyte beta-2-adrenoceptors: abnormality in es...
8759567 - Benign paroxysmal positional vertigo.
Publication Detail:
Type:  Journal Article; Randomized Controlled Trial; Research Support, Non-U.S. Gov't     Date:  2006-02-07
Journal Detail:
Title:  Thorax     Volume:  61     ISSN:  0040-6376     ISO Abbreviation:  Thorax     Publication Date:  2006 Jul 
Date Detail:
Created Date:  2006-06-29     Completed Date:  2006-07-28     Revised Date:  2013-06-07    
Medline Journal Info:
Nlm Unique ID:  0417353     Medline TA:  Thorax     Country:  England    
Other Details:
Languages:  eng     Pagination:  559-67     Citation Subset:  IM    
Department of Medicine, Respiratory Investigation Unit, Queen's University, Kingston, Ontario, Canada.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Bronchodilator Agents / therapeutic use*
Combined Modality Therapy / methods
Cross-Over Studies
Double-Blind Method
Dyspnea / physiopathology,  therapy*
Exercise Therapy / methods
Exercise Tolerance / physiology*
Middle Aged
Oxygen / therapeutic use*
Pulmonary Disease, Chronic Obstructive / physiopathology,  therapy*
Respiratory Function Tests
Treatment Outcome
Reg. No./Substance:
0/Bronchodilator Agents; 7782-44-7/Oxygen
Comment In:
Thorax. 2006 Jul;61(7):551-2   [PMID:  16807386 ]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Multiple left ventricular myxomas arising from the interventricular septum and ventricular trabecula...
Next Document:  Performance of mechanical ventilators at the patient's home: a multicentre quality control study.