Document Detail

Qualitative aspects of exertional dyspnea in patients with interstitial lung disease.
MedLine Citation:
PMID:  9609795     Owner:  NLM     Status:  MEDLINE    
We compared qualitative and quantitative aspects of perceived exertional dyspnea in patients with interstitial lung disease (ILD) and normal subjects and sought a physiological rationale for their differences. Twelve patients with ILD [forced vital capacity = 64 +/- 4 (SE) %predicted] and 12 age-matched normal subjects performed symptom-limited incremental cycle exercise tests with measurements of dyspnea intensity (Borg scale), ventilation, breathing pattern, operational lung volumes, and esophageal pressures (Pes). Qualitative descriptors of dyspnea were selected at exercise cessation. Both groups described increased "work and/or effort" and "heaviness" of breathing; only patients with ILD described "unsatisfied inspiratory effort" (75%), "increased inspiratory difficulty" (67%), and "rapid breathing" (58%) (P < 0.05 patients with ILD vs. normal subjects). Borg-O2 uptake (VO2) and Borg-ventilation slopes were significantly greater during exercise in patients with ILD (P < 0.01). At peak exercise, when dyspnea intensity and inspiratory effort (Pes-to-maximal inspiratory pressure ratio) were similar, the distinct qualitative perceptions of dyspnea in patients with ILD were attributed to differences in dynamic ventilatory mechancis, i.e., reduced inspiratory capacity, heightened Pes-to-tidal volume ratio, and tachypnea. Factors contributing to dyspnea intensity in both groups were also different: the best correlate of the Borg-VO2 slope in patients with ILD was the resting tidal volume-to-inspiratory capacity ratio (r = 0.58, P < 0.05) and in normal subjects was the slope of Pes-to-maximal inspiratory pressure ratio over VO2 (r = 0.60, P < 0. 05).
D E O'Donnell; L K Chau; K A Webb
Related Documents :
6313755 - Central nervous system site of action for the respiratory depressant effect of diacetyl...
3970455 - Inspiratory muscle training in patients with chronic obstructive pulmonary disease.
8769505 - Ventilatory response to continuous incremental changes in respiratory resistance in pat...
7380705 - Diaphragmatic function in healthy subjects during partial curarization.
18460985 - Predictors of supervised exercise adherence during breast cancer chemotherapy.
17505155 - Corticotroph axis sensitivity after exercise: comparison between elite athletes and sed...
Publication Detail:
Type:  Clinical Trial; Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Journal of applied physiology (Bethesda, Md. : 1985)     Volume:  84     ISSN:  8750-7587     ISO Abbreviation:  J. Appl. Physiol.     Publication Date:  1998 Jun 
Date Detail:
Created Date:  1998-07-07     Completed Date:  1998-07-07     Revised Date:  2013-09-26    
Medline Journal Info:
Nlm Unique ID:  8502536     Medline TA:  J Appl Physiol (1985)     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  2000-9     Citation Subset:  IM    
Division of Respiratory and Critical Care Medicine, Department of Medicine, Queen's University, Kingston, Ontario, Canada K7L 2V7.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Dyspnea / physiopathology*
Exercise / physiology*
Exercise Test
Lung Diseases, Interstitial / physiopathology*
Lung Volume Measurements
Middle Aged
Oxygen Consumption / physiology
Regression Analysis
Respiratory Function Tests
Respiratory Mechanics / physiology

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

Previous Document:  Pyridoxalated hemoglobin polyoxyethylene conjugate reverses hyperdynamic circulation in septic sheep...
Next Document:  Redistribution of pulmonary blood flow during unilateral hypoxia in prone and supine dogs.