Measurement of Dynamic Hyperinflation After a 6-Minute Walk Test in Patients With COPD

doi:10.1378/chest.09-0410

Chest

Volume 136, Issue 6, December 2009, Pages 1466-1472

https://doi.org/10.1378/chest.09-0410 Get rights and content

Background

Dynamic hyperinflation (DH) develops in patients with COPD during incremental exercise with a cycle ergometer. The aims of this study were to determine whether DH can be evidenced after walking with a handheld spirometer and to determine its functional consequences.

Methods

Fifty patients with COPD (39 men; median age, 60 years [interquartile range (IQR), 54 to 69 years]; FEV₁, 45% predicted [IQR, 31 to 67% predicted]) underwent pulmonary function tests and a 6-min walk test (6MWT). Inspiratory capacity (IC) was measured with the patient in the standing position at rest and immediately after the 6MWT with a portable spirometer. Dyspnea was evaluated directly (change in Borg score during 6MWT) and indirectly (Medical Research Council scale). The first 20 patients performed an incremental exercise test with cycle ergometer that allowed for the measurement of IC at peak exercise and repeatedly during the first 3 min of recovery.

Results

The median change in IC during the 6MWT was −210 mL (IQR, 55 to −440; n = 50), whereas the median change in IC during the exercise test was −295 mL (IQR, −145 to −515; n = 20). Both the IC and IC changes after 6MWT correlated to values after the exercise test. DH decreased rapidly after the end of the exercise test but was nonsignificantly different from the baseline value after 75 s of recovery. The percentage of decrease in IC during the 6MWT correlated with dyspnea (change in Borg score during 6MWT: r² = 0.21; p = 0.0006).

Conclusions

DH can be measured during a 6MWT with a handheld spirometer to allow for its evaluation in daily practice and its contribution to dyspnea while walking.

Section snippets

Design

The first 20 patients underwent both a 6MWT and an exercise test with cycle ergometer to allow for the comparison of ICs obtained from both tests (part of their checkup before rehabilitation). Thirty additional patients, who had performed a 6MWT and had undergone additional indirect measures of dyspnea (ie, measurement of the baseline dyspnea index [BDI] and the number of flights of stairs walked), were included in the study (Fig 1).

Patients

Patients with COPD were enrolled consecutively and were

Results

The clinical and functional characteristics of the 50 patients with COPD are described in Table 1. Their median age was 60 years (range, 54 to 69 years), and the median FEV₁ was 45% predicted (range, 31% to 67% predicted).

The IC measured with the patient in the standing position (before the 6MWT) tended to be higher than that with the patient in the sitting position for all patients (p = 0.064). The median change in IC during the 6MWT for all patients was −210 mL (range, 55 to −440 mL), whereas

Discussion

The main results of this study are the demonstration that DH can be easily assessed after a 6MWT, correlated to that measured during an incremental exercise test, and correlated to both direct and indirect measures of dyspnea, whereas performance during the 6MWT was mainly related to hyperinflation at rest. Our methodological measurement of IC was different from that adopted by Marin et al.² In their study, IC was determined using pneumotachography by having the patients inhale while seated.

Acknowledgments

Author contributions: Drs. Callens, Graba, Gillet-Juvin, and Essalhi carried out the measurements of IC at walk, participated in the design of the study, and drafted the manuscript. Dr. Bidaud-Chevalier participated in data collection and helped to draft the manuscript. Drs. Peiffer and Mahut participated in the design, performed the statistical analysis, and helped to draft the manuscript. Dr. Delclaux conceived of the study, performed exercise tests, participated in its design and

References (0)

Cited by (52)

Dynamic hyperinflation is a risk factor for mortality and severe exacerbations in COPD patients
2024, Respiratory Medicine
To assess if dynamic hyperinflation is an independent risk factor for mortality and severe exacerbations in COPD patients.
A cohort of 141 patients with stable COPD and moderate to very severe airflow limitation, treated according to conventional guidelines, was followed for a median of 9 years. Clinical characteristics were recorded and arterial blood gases, pulmonary function tests, 6-min walk and incremental exercise test with measurement of respiratory pattern and operative lung volumes were performed. Endpoints were all-cause mortality and hospitalization for COPD exacerbation.
58 patients died during the follow-up period (1228 patients x year). The mortality rate was higher in patients with dynamic hyperinflation (n = 106) than in those without it (n = 35) (14.6; 95% CI, 14.5–14.8 vs. 7.2; 95% CI, 7.1–7.4 per 1000 patients-year). After adjusting for sex, age, body mass index, pack-years and treatment with inhaled corticosteroids, dynamic hyperinflation was associated with a higher mortality risk (adjusted hazard ratio [aHR], 2.725; 95% CI, 1.010–8.161), and in a multivariate model, comorbidity, peak oxygen uptake and dynamic hyperinflation were retained as independent predictors of mortality. The time until first severe exacerbation was shorter for patients with dynamic hyperinflation (aHR, 3.961; 95% CI, 1.385–11.328), and dynamic hyperinflation, FEV₁ and diffusing capacity were retained as independent risk factors for severe exacerbation. Moreover, patients with dynamic hyperinflation had a higher hospitalization risk than those without it (adjusted incidence rate ratio, 1.574; 95% CI, 1.087–2.581).
In stable COPD patients, dynamic hyperinflation is an independent prognostic factor for mortality and severe exacerbations.
Is there an optimal level of positive expiratory pressure (PEP) to improve walking tolerance in patients with severe COPD?
2016, Archivos de Bronconeumologia
Citation Excerpt :
Nevertheless, in our “ad hoc” analysis, we found that the application of low level PEP produces a greater improvement in the distance covered in the group of patients with no dynamic hyperinflation, compared to the group of patients who presented dynamic hyperinflation. This was in line with the findings of Callens et al., who observed that change in IC after walking does not correlate with 6MWD.25 In conclusion, it is difficult to compare the effects of PEP on exercise tolerance in patients with COPD, because the published studies are too heterogeneous, and use a variety of exercise protocols, types and levels of PEP and outcome measures.
The application of positive expiratory pressure (PEP) devices during exercise had been proposed in order to counteract the pulmonary hyperinflation, reduce the dyspnea and thus increase the exercise tolerance in patients with severe chronic obstructive pulmonary disease (COPD). This randomized controlled crossover trial investigated the effect of two different levels of PEP (1 cmH₂O and 10 cmH₂O) on distance covered at 6 min walk test (6MWT) in patients with severe COPD. Secondary outcomes were the evaluation of PEP effects on physiological and pulmonary function variables.
Seventy-two severe COPD patients, referred to our hospitals as in and out patients, were recruited. A basal 6MWT without devices was performed on the first day, and then repeated with PEP 1 cmH₂O (PEP1) and 10 cmH₂O (PEP10), with a randomized crossover design. Slow and forced spirometries, including the inspiratory capacity measure, were repeated before and after each 6MWT.
50 patients (average age 69.92 year, mean FEV₁ 41.42% of predicted) concluded the trial. The 6MWT improved significantly among both PEP levels and baseline (323.8 mt at baseline vs 337.8 PEP1 and 341.8 PEP10; P<.002 and P<.018, respectively). The difference between PEP10 and PEP1 did not reach the significance. No improvements were found in pulmonary function, symptoms and physiological variables after the 6MWT.
In patients with severe COPD, the application of 1 cmH₂O of PEP seems to improve the exercise tolerance as 10 cmH₂O, with similar dyspnea. Further studies should investigate the effects of low levels of PEP on aerobic training programs.
La aplicación de dispositivos de presión espiratoria positiva (PEP) durante el ejercicio se había propuesto con el objetivo de contrarrestar la hiperinflación pulmonar, reducir la disnea y mejorar así la tolerancia al ejercicio de los pacientes con enfermedad pulmonar obstructiva crónica (EPOC) grave. En este ensayo controlado, aleatorizado y cruzado se investigó el efecto de dos niveles de PEP (1 cm de H₂O y 10 cm de H₂O) sobre la distancia recorrida por pacientes con EPOC grave durante la prueba de marcha de 6 min (PM6 M). Los criterios de valoración secundarios fueron los efectos de la PEP sobre variables fisiológicas y de la función pulmonar.
Se reclutaron setenta y dos pacientes con EPOC grave, hospitalizados o ambulatorios, derivados a nuestros hospitales. El primer día de este estudio aleatorizado y cruzado se efectuó la PM6 M sin ningún dispositivo, y posteriormente se repitió con una PEP de 1 cm de H₂O (PEP1) y de 10 cm de H₂O (PEP10). Antes y después de cada PM6 M se practicaron espirometrías lentas y forzadas, que incluyeron la medición de la capacidad inspiratoria.
Cincuenta pacientes (edad media 69,92 años, FEV₁ medio 41,42% del previsto) finalizaron el ensayo. La PM6 M mejoró significativamente con los dos niveles de PEP, en comparación con la situación inicial (323,8 m al inicio vs 337,8 con la PEP1 y 341,8 con la PEP10; p < 0,002 y p < 0,018, respectivamente). La diferencia entre la PEP10 y la PEP1 no fue significativa. No se observaron mejorías en la función pulmonar, los síntomas ni las variables fisiológicas posteriores a la prueba PM6 M.
En pacientes con EPOC grave, la aplicación de una PEP de 1 cm de H₂O parece mejorar la tolerancia al ejercicio, al igual que lo hace la aplicación de 10 cm H₂O y con un grado similar de disnea. Deben realizarse otros estudios para investigar los efectos de los niveles bajos de PEP en los programas de entrenamiento aeróbico.
Assessment of dyspnea and dynamic hyperinflation in male patients with chronic obstructive pulmonary disease during a six minute walk test and an incremental treadmill cardiorespiratory exercise test
2017, Revista Portuguesa de Pneumologia (English Edition)
Citation Excerpt :
This can be justified by the complexity of achieving reliable manoeuvers with acceptable reproducibility. Interbedded manoeuvers raise the possibility of changing DH levels and alter the perception of symptoms during the test, which could be impaired with respect to their usual performance.30,31 The degree of DH during the 6MWT may also have been underestimated because of the time taken by the patient upon completing the test to approach the spirometer to perform the IC maneuver, which in our case was avoided by keeping the same walking pace of the test for approaching the spirometer.
The six minute walk test (6MWT) is a standardized test that provides information on exercise capacity in patients with COPD. It is considered a submaximal test in opposition to incremental cardiopulmonary exercise tests (CPET) that provide valuable information on all the systems involved in exercise.
1. To compare the perceptive, physiological responses and degree of dynamic hyperinflation during two exercise tests: the 6MWT and the incremental CPET on a treadmill. 2. To evaluate how dyspnea is related to dynamic hyperinflation (DH) and other functional parameters in both tests.
29 stable COPD male patients, age 68 ± 5.8 years, mean post-bronchodilator FEV1 57 ± 11%, were recruited. To evaluate dynamic hyperinflation, inspiratory capacity (IC) was measured at rest and upon completing each one of the tests. At the same time, perceived dyspnea and leg discomfort were rated on specific modified Borg scales.
The mean walk distance in 6MWT was 494 ± 88 m. The Borg scale rating for shortness of breath upon completing the test was 4.7 ± 2, whilst 2.9 ± 2 for leg discomfort. IC changed from 2.53 ± 0.63 l before to 2.34 ± 0.60 l after completion of the test.
In the treadmill CPET, maximal oxygen consumption ( $\dot{V} O_{2} \max$ ) was 21.8 ± 5 mL/kg/min with 6.6 ± 2 dyspnea and 4.3 ± 2 leg discomfort on Borg scales. IC changed from 2.17 ± 0.53 l to 1.20 ± 0.43 l.
Dynamic hyperinflation occurs in male COPD patients during submaximal exercise such as the 6MWT. This phenomenon is more pronounced after incremental CPET on a treadmill. Despite being dyspnea the dominant limiting symptom for both tests, we observed different physiological responses.
Effects of cardiorespiratory rehabilitation program on submaximal exercise in patients with long-COVID-19 conditions: a systematic review of randomized controlled trials and recommendations for future studies
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Maximal Voluntary Ventilation Should Not Be Estimated From the Forced Expiratory Volume in the First Second in Healthy People and COPD Patients
2020, Frontiers in Physiology
Effects of weight loss on dynamic hyperinflation in obese women asthmatics
2019, Journal of Applied Physiology

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Original ResearchCOPDMeasurement of Dynamic Hyperinflation After a 6-Minute Walk Test in Patients With COPD

Background

Methods

Results

Conclusions

Section snippets

Design

Patients

Results

Discussion

Acknowledgments

Original Research
COPD
Measurement of Dynamic Hyperinflation After a 6-Minute Walk Test in Patients With COPD