Back to Journals » International Journal of Chronic Obstructive Pulmonary Disease » Volume 15

Evaluation of Exertional Ventilatory Parameters Using Oscillometry in COPD

Authors Yamamoto Y, Miki K, Matsuki T, Fukushima K, Oshitani Y, Kagawa H, Tsujino K, Yoshimura K, Miki M, Kida H

Received 30 April 2020

Accepted for publication 2 July 2020

Published 13 July 2020 Volume 2020:15 Pages 1697—1711

DOI https://doi.org/10.2147/COPD.S260735

Checked for plagiarism Yes

Review by Single-blind

Peer reviewer comments 3

Editor who approved publication: Dr Richard Russell


Yuji Yamamoto, Keisuke Miki, Takanori Matsuki, Kiyoharu Fukushima, Yohei Oshitani, Hiroyuki Kagawa, Kazuyuki Tsujino, Kenji Yoshimura, Mari Miki, Hiroshi Kida

Department of Respiratory Medicine, National Hospital Organization Osaka Toneyama Medical Center, Osaka, Japan

Correspondence: Keisuke Miki
Department of Respiratory Medicine, National Hospital Organization Osaka Toneyama Medical Center, 5-1-1 Toneyama, Toyonaka, Osaka 560-8552, Japan
Tel +81-6-6853-2001
Fax +81-6-6853-3127
Email miki.keisuke.pu@mail.hosp.go.jp

Background: Oscillometry is a tool to measure respiratory impedance that requires minimal patients’ effort. In patients with chronic obstructive pulmonary disease (COPD), the correlation of respiratory impedance at rest with exertional ventilatory parameters, including exercise tolerance, has scarcely been reported. In addition, the utility of oscillometric parameters might differ between the inspiratory and expiratory phases due to airflow obstruction during expiration, but the hypothesis had not been validated. The aim of the present study was to investigate whether oscillometric parameters are associated with exertional ventilatory parameters in patients with COPD.
Methods: Fifty-five subjects with COPD who attended clinics at the National Hospital Organization Osaka Toneyama Medical Center performed spirometry, oscillometry, and cardiopulmonary exercise testing (CPET) within 2 weeks. The correlations between parameters of spirometry, oscillometry, and CPET were analyzed using Spearman’s rank correlation coefficient, univariate, and multivariate analyses.
Results: Respiratory reactance had better correlations with the CPET parameters than respiratory resistance. Moreover, inspiratory reactance at rest correlated with the CPET parameters stronger than expiratory reactance. In particular, inspiratory resonant frequency (Fres-ins) correlated with peak oxygen uptake (rS=− 0.549, p< 0.01) and dead space to tidal volume ratio at peak exercise (rS=0.677, p< 0.01) and the best predicted expiratory tidal volume (VT ex) at peak exercise of all the oscillometric parameters (rS=− 0.679, p< 0.01). However, the correlation between Fres-ins and VT ex at peak exercise became weak in subjects with severe and very severe COPD during exercise.
Conclusion: Measurement of respiratory reactance is useful for the effortless evaluation of not only exertional ventilatory parameters but exercise tolerance in patients with COPD. The correlation of respiratory impedance with exertional ventilatory parameters can become weak in patients with advanced COPD; thus, the measurement of oscillometry might not be appropriate for evaluating exertional ventilatory parameters of patients with advanced COPD.

Keywords: dyspnea, dynamic hyperinflation, airflow obstruction, resonant frequency, tidal volume

Creative Commons License This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at https://www.dovepress.com/terms.php and incorporate the Creative Commons Attribution - Non Commercial (unported, v3.0) License. By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms.

Download Article [PDF]  View Full Text [HTML][Machine readable]