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. 2020 Dec 21;6(4):00589-2020.
doi: 10.1183/23120541.00589-2020. eCollection 2020 Oct.

Diaphragmatic excursion correlates with exercise capacity and dynamic hyperinflation in COPD patients

Masashi Shiraishi  1   2 , Yuji Higashimoto  1 , Ryuji Sugiya  1 , Hiroki Mizusawa  1 , Yu Takeda  1 , Shuhei Fujita  1 , Osamu Nishiyama  2 , Shintarou Kudo  3 , Tamotsu Kimura  1 , Yasutaka Chiba  4 , Kanji Fukuda  1 , Yuji Tohda  2
Affiliations

Diaphragmatic excursion correlates with exercise capacity and dynamic hyperinflation in COPD patients

Masashi Shiraishi et al. ERJ Open Res. .

Abstract

Background: Although the pathophysiological mechanisms involved in the development of dyspnoea and poor exercise tolerance in patients with COPD are complex, dynamic lung hyperinflation (DLH) plays a central role. Diaphragmatic excursions can be measured by ultrasonography (US) with high intra- and interobserver reliability. The objective of this study was to evaluate the effect of diaphragmatic excursions as assessed by US on exercise tolerance and DLH in patients with COPD.

Methods: Patients with COPD (n=20) and age-matched control subjects (n=20) underwent US, which was used to determine the maximum level of diaphragmatic excursion (DEmax). Ventilation parameters, including the change in inspiratory capacity (ΔIC), were measured in the subjects during cardiopulmonary exercise testing (CPET). We examined the correlations between DEmax and the ventilation parameters.

Results: The DEmax of patients with COPD was significantly lower than that of the controls (45.0±12.8 mm versus 64.6±6.3 mm, respectively; p<0.01). The perception of peak dyspnoea (Borg scale) was significantly negatively correlated with DEmax in patients with COPD. During CPET, oxygen uptake/weight (V'O2 /W) and minute ventilation (V'E) were significantly positively correlated with DEmax, while V'E/V'O2 and V'E/carbon dioxide output (V'CO2 ) were significantly negatively correlated with DEmax in patients with COPD. DEmax was also significantly positively correlated with ΔIC, reflecting DLH, and with V'O2 /W, reflecting exercise capacity.

Conclusion: Reduced mobility of the diaphragm was related to decreased exercise capacity and increased dyspnoea due to dynamic lung hyperinflation in COPD patients.

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Conflict of interest statement

Conflict of interest: M. Shiraishi has nothing to disclose. Conflict of interest: Y. Higashimoto has nothing to disclose. Conflict of interest: R. Sugiya has nothing to disclose. Conflict of interest: H. Mizusawa has nothing to disclose. Conflict of interest: Y. Takeda has nothing to disclose. Conflict of interest: S. Fujita has nothing to disclose. Conflict of interest: O. Nishiyama has nothing to disclose. Conflict of interest: S. Kudo has nothing to disclose. Conflict of interest: T. Kimura has nothing to disclose. Conflict of interest: Y. Chiba has nothing to disclose. Conflict of interest: K. Fukuda has nothing to disclose. Conflict of interest: Y. Tohda reports grants from Kyorin Pharmaceutical, MeijiSeika Pharma, Boehringer Ingelheim, Teijin Pharma, DaiichiSankyo, Astellas andPearl outside the submitted work.

Figures

FIGURE 1
FIGURE 1
Representative image of right diaphragm. The probe was positioned below the right costal margin between the midclavicular and anterior axillary lines. a) Two-dimensional ultrasonographic image of the right hemidiaphragm (B-mode). Diaphragmatic movements were recorded in b) M-mode during quiet breathing and c) during deep breathing (DEmax). DEmax: maximum diaphragmatic excursion.
FIGURE 2
FIGURE 2
Maximum diaphragmatic exertion during deep breathing (DEmax) in COPD patients (n=20) and control participants (n=20). DEmax in COPD patients was significantly smaller than that in control participants. **: p<0.01.
FIGURE 3
FIGURE 3
Correlation between maximum diaphragmatic excursion (DEmax) and peak change in inspiratory capacity (ΔIC) in a) patients with COPD (n=20) and b) healthy participants (n=20). ΔIC, which reflects dynamic lung hyperinflation, was significantly positively correlated with DEmax in patients with COPD, while ΔIC was not correlated with DEmax in control participants.
FIGURE 4
FIGURE 4
Correlation between maximum diaphragmatic excursion (DEmax) and peak oxygen uptake (V′O2)/weight (W) in a) patients with COPD (n=20) and b) healthy participants (n=20). DEmax was significantly positively correlated with V′O2/W in both patients with COPD and healthy participants.
See this image and copyright information in PMC

References

    1. Gagnon P, Guenette JA, Langer D, et al. . Pathogenesis of hyperinflation in chronic obstructive pulmonary disease. Int J COPD 2014; 9: 187–201. - PMC - PubMed
    1. Calverley PMA, Koulouris NG. Flow limitation and dynamic hyperinflation: key concepts in modern respiratory physiology. Eur Respir J 2005; 25: 186–199. doi:10.1183/09031936.04.00113204 - DOI - PubMed
    1. Khirani S, Polese G, Aliverti A, et al. . On-line monitoring of lung mechanics during spontaneous breathing: a physiological study. Respir Med 2010; 104: 463–471. doi:10.1016/j.rmed.2009.09.014 - DOI - PubMed
    1. Cooper CB. The connection between chronic obstructive pulmonary disease symptoms and hyperinflation and its impact on exercise and function. Am J Med 2006; 119: 21–31. doi:10.1016/j.amjmed.2006.08.004 - DOI - PubMed
    1. Laveneziana P, Albuquerque A, Aliverti A, et al. . ERS statement on respiratory muscle testing at rest and during exercise. Eur Respir J 2019; 53: 1801214. doi:10.1183/13993003.01214-2018 - DOI - PubMed

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