Effects of inhaled short-acting bronchodilators on diaphragm function and neural respiratory drive during maximal isocapnic ventilation in patients with chronic obstructive pulmonary disease.
- Author:
Yun LI
1
;
Yin-Huan LI
;
Yu-Wen LUO
;
Rui XIAO
;
Jin-Lun HUANG
;
Kai WANG
;
Xin CHEN
Author Information
- Publication Type:Journal Article
- MeSH: Administration, Inhalation; Albuterol; therapeutic use; Bronchodilator Agents; therapeutic use; Diaphragm; drug effects; Humans; Ipratropium; therapeutic use; Pulmonary Disease, Chronic Obstructive; drug therapy; Respiration
- From: Journal of Southern Medical University 2016;36(2):232-237
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVETo investigate the effects of inhaled short-acting bronchodilators on diaphragm function and neural respiratory drive in patients with chronic obstructive pulmonary disease (COPD) during maximal isocapnic ventilation (MIV).
METHODSForty-seven patient with moderate to severe COPD were randomized into 4 groups: placebo group (n=12), salbutamol group (n=13), ipratropium group (n=10), and combined group (salbutamol and ipratropium, n=12). Each subject received an initial MIV for 3 min at baseline and inhaled placebo (400 µg), salbutamol (400 µg), ipratropium (80 µg), or both salbutamol and ipratropium, followed 30 min later by another 3 min of MIV. The parameters of diaphragm function and neural respiratory drive were monitored continuously and calculated during MIV.
RESULTSDuring the initial MIV, all the patients experienced a linear increase in root mean square (RMS) of diaphragm electromyogram with a gradual decrease in transdiaphragmatic pressure (Pdi), minute ventilation (VE), and VE/RMS, and these parameters all improved significantly after inhalation of the bronchodilators. Compared with the placebo group at the same time point, the 3 bronchodilator-treated groups showed significantly decreased RMS and Borg score and increased Pdi, VE and VE/RMS; VE/RMS was the highest in the combined treatment group (P<0.05). The Delta Borg was significantly correlated with Delta Pdi, Delta VE, Delta RMS, and Delta VE/RMS (P<0.05).
CONCLUSIONSIn COPD patients, inhaled short-acting bronchodilators can alleviate diaphragm fatigue during MIV, increase lung ventilation, reduce neural respiratory drive, and improve neuro-ventilatory coupling to relieve dyspnoea, and the combination of β-2 agonists and anti-muscarinic antagonists produces a stronger efficacy.