| Autor: |
Audrey Herpeux, Inge Muylle, Vincent Ninane, Anneleen Peeters, Maria Gabrovska |
| Rok vydání: |
2016 |
| Předmět: |
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| Zdroj: |
4.1 Clinical Physiology, Exercise and Functional Imaging. |
| DOI: |
10.1183/13993003.congress-2016.oa2014 |
| Popis: |
Introduction: maximal voluntary ventilation (MVV) correlates well with maximal exercise capacity and is used to assess the ventilatory function during exercise in COPD patients. Dynamic hyperinflation (DH) often occurs during MVV in COPD and is believed to be due to expiratory flow limitation. The present study has assessed whether DH can also occur during MVV in normal subjects without expiratory flow limitation. Methods: 43 subjects (25 men) with normal lung function performed MVV at increasing breathing frequencies and maximal tidal volume, from 10 to 100 cycles per minute. Inspiratory capacity (IC) was measured at rest and after each 12 seconds of MVV in order to detect DH. From the moment DH appeared at a given frequency, only one additional MVV at a higher breathing frequency was conducted to confirm DH. Results: DH appeared at or before 100 cycles per minute in 86% of the subjects (37/43), mainly between 40 and 70 cycles per minute. No correlation was found between the cycle associated with DH occurrence and age, body mass index or lung volume and flows. Conclusion: DH quickly occurs during increasing breathing frequency at maximal tidal volume in normal subjects suggesting that DH during MVV in COPD patients is not only due to expiratory flow limitation. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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