TY - JOUR
T1 - High-intensity exercise impairs extradiaphragmatic respiratory muscle perfusion in patients with COPD
AU - Louvaris, Zafeiris
AU - Rodrigues, Antenor
AU - Dacha, Sauwaluk
AU - Gojevic, Tin
AU - Janssens, Wim
AU - Vogiatzis, Ioannis
AU - Gosselink, Rik
AU - Langer, Daniel
N1 - Funding Information:
This research project was supported by Research Foundation Flanders (FWO): G0A4516N -ZKC9570 - C22/15/035. Dr. Z. Louvaris was recipient of an ERS fellowship (LTRF 2016–6686) and a postdoctoral fellow of Research Foundation Flanders (FWO - 12U5618N). A. Rodrigues was supported by the Coordination for the Improvement of Higher Education Personnel (CAPES), Brazil (88881.188754/2018-01). Prof. S. Dacha was supported by Chiang Mai University’s scholarship, Chiang Mai, Thailand (Ref. No. 6392 (7)/0807).
Publisher Copyright:
Copyright © 2021 the American Physiological Society 325
PY - 2021/2/1
Y1 - 2021/2/1
N2 - The study investigated whether high-intensity exercise impairs inspiratory and expiratory muscle perfusion in patients with COPD. We compared respiratory local muscle perfusion between constant-load cycling (sustained at 80% WRpeak) and voluntary normocapnic hyperpnoea reproducing similar work of breathing (WoB) in 18 patients (FEV1:58±24% predicted). Local muscle blood flow index (BFI), using indocyanine green dye and fractional oxygen saturation (%StiO2)were simultaneously assessed by near-infrared spectroscopy (NIRS) over the intercostal, scalene, rectus abdominis and vastus lateralis muscles. Cardiac output (impedance cardiography), WoB (oesophageal/gastric balloon catheter), and diaphragmatic and extradiaphragmatic respiratory muscle electromyographic activity (EMG) were also assessed throughout cycling and hyperpnoea. Minute ventilation, breathing pattern, WoB and respiratory muscle EMG were comparable between cycling and hyperpnoea. During cycling, cardiac output and vastus lateralis BFI were significantly greater compared to hyperpnoea [by +4.2(2.6-5.9) L/min and +4.9(2.2-7.8) nmol/s], respectively, (p<0.01). Muscle BFI and %StiO2 were respectively lower during cycling compared to hyperpnoea in scalene [by -3.8(-6.4- -1.2) nmol/s and -6.6(-8.2- -5.1)%], intercostal [by -1.4(-2.4- -0.4) nmol/s and -6.0(-8.6- -3.3)%] and abdominal muscles [by -1.9(-2.9- -0.8) nmol/s and -6.3(-9.1- -3.4)%] (p<0.001). The difference in respiratory (scalene and intercostal) muscle BFI between cycling and hyperpnoea was associated with greater dyspnoea (Borg CR10) scores (r= -0.54 and r= -0.49, respectively, p<0.05). These results suggest that in patients with COPD 1) locomotor muscle work during high-intensity exercise impairs extradiaphragmatic respiratory muscle perfusion and that 2) insufficient adjustment in extradiaphragmatic respiratory muscle perfusion during high-intensity exercise may partly explain the increased sensations of dyspnoea.
AB - The study investigated whether high-intensity exercise impairs inspiratory and expiratory muscle perfusion in patients with COPD. We compared respiratory local muscle perfusion between constant-load cycling (sustained at 80% WRpeak) and voluntary normocapnic hyperpnoea reproducing similar work of breathing (WoB) in 18 patients (FEV1:58±24% predicted). Local muscle blood flow index (BFI), using indocyanine green dye and fractional oxygen saturation (%StiO2)were simultaneously assessed by near-infrared spectroscopy (NIRS) over the intercostal, scalene, rectus abdominis and vastus lateralis muscles. Cardiac output (impedance cardiography), WoB (oesophageal/gastric balloon catheter), and diaphragmatic and extradiaphragmatic respiratory muscle electromyographic activity (EMG) were also assessed throughout cycling and hyperpnoea. Minute ventilation, breathing pattern, WoB and respiratory muscle EMG were comparable between cycling and hyperpnoea. During cycling, cardiac output and vastus lateralis BFI were significantly greater compared to hyperpnoea [by +4.2(2.6-5.9) L/min and +4.9(2.2-7.8) nmol/s], respectively, (p<0.01). Muscle BFI and %StiO2 were respectively lower during cycling compared to hyperpnoea in scalene [by -3.8(-6.4- -1.2) nmol/s and -6.6(-8.2- -5.1)%], intercostal [by -1.4(-2.4- -0.4) nmol/s and -6.0(-8.6- -3.3)%] and abdominal muscles [by -1.9(-2.9- -0.8) nmol/s and -6.3(-9.1- -3.4)%] (p<0.001). The difference in respiratory (scalene and intercostal) muscle BFI between cycling and hyperpnoea was associated with greater dyspnoea (Borg CR10) scores (r= -0.54 and r= -0.49, respectively, p<0.05). These results suggest that in patients with COPD 1) locomotor muscle work during high-intensity exercise impairs extradiaphragmatic respiratory muscle perfusion and that 2) insufficient adjustment in extradiaphragmatic respiratory muscle perfusion during high-intensity exercise may partly explain the increased sensations of dyspnoea.
KW - COPD
KW - Exercise
KW - NIRS
KW - Perfusion
KW - Respiratory muscles
UR - http://www.scopus.com/inward/record.url?scp=85102052742&partnerID=8YFLogxK
U2 - 10.1152/japplphysiol.00659.2020
DO - 10.1152/japplphysiol.00659.2020
M3 - Article
SN - 8750-7587
VL - 130
SP - 325
EP - 341
JO - Journal of Applied Physiology
JF - Journal of Applied Physiology
IS - 2
ER -