[Quantitative evaluation of dyspnea and the effects of M-receptor antagonist on dyspnea in patients with chronic obstructive pulmonary disease].
OBJECTIVE
To study the method of quantitative evaluation of dyspnea and to investigate the effects of M-receptor antagonist inhalation on dyspnea in patients with chronic obstructive pulmonary disease (COPD) during exercise.


METHODS
Cycle exercise test was used in 27 patients with COPD and the effects of ipratropium bromide, a M-receptor antagonist, by inhalation on dyspnea and exercise capacity in the patients were observed.


RESULTS
(1) Dyspnea index as Borg scale was closely correlated with oxygen uptake (V(O2)) during exercise in all the patients. Three variables for quantitative evaluation of dyspnea could be derived from the linear regression line. They were Borg scale slope (BSS), threshold load of dyspnea (TLD), and breakpoint load of dyspnea(BLD). (2) BSS was negatively correlated with forced expiratory volume in one second to forced vital capacity ratio (r = -0.519, P < 0.01) and diffusing capacity of the lungs for carbon monoxide (r = -0.497, P < 0.01) but positively correlated with residual volume/total lung capacity (r = 0.396, P < 0.05). (3) Inhalation of ipratropium bromide could significantly improve BSS [from (12.09 +/- 3.41) BS x L(-1) x min(-1) to (8.57 +/- 2.79) BS x L(-1) x min(-1), P < 0.01] and BLD [from (0.77 +/- 0.19) L/min to (0.81 +/- 0.14) L/min, P < 0.05] during exercise.


CONCLUSIONS
(1) BSS, TLD and BLD could be used as reliable and convenient variables in quantitative evaluation of dyspnea in patients with COPD. BSS and BLD could to some extent reflect the severity of the disease. (2) M-receptor antagonists could alleviate dyspnea and increase exercise capacity in patients with COPD.
Liu
G
G
Institute of Respiratory Diseases, China Medical University, Shenyang 110001, China.
Liu
Z
Z
Song
Y
Y
Yu
R
R
D000328:Adult; D000368:Aged; D004417:Dyspnea / Q000188:drug therapy*; D005260:Female; D006801:Humans; D009241:Ipratropium / Q000627:therapeutic use*; D008168:Lung / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D018727:Muscarinic Antagonists / Q000627:therapeutic use*; D029424:Pulmonary Disease, Chronic Obstructive / Q000150:complications* / Q000503:physiopathology
D018727:Muscarinic Antagonists; D009241:Ipratropium