Flow controlled expiration does not impair pedal power during physical exercise on a bicycle ergometer

Stefan Schumann; Nina Berger; Sara Lozano-Zahonero; Steffen Wirth

doi:10.1016/j.resp.2019.103303

Flow controlled expiration does not impair pedal power during physical exercise on a bicycle ergometer

Respir Physiol Neurobiol. 2020 Jan:271:103303. doi: 10.1016/j.resp.2019.103303. Epub 2019 Sep 20.

Authors

Stefan Schumann¹, Nina Berger², Sara Lozano-Zahonero³, Steffen Wirth⁴

Affiliations

¹ Department of Anesthesiology and Critical Care, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany; Laboratory of origin: Workgroup Clinical Respiration Physiology, Hugstetter Straße 55, D-79106 Freiburg, Germany. Electronic address: stefan.schumann@uniklinik-freiburg.de.
² Department of Anesthesiology and Critical Care, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany; Laboratory of origin: Workgroup Clinical Respiration Physiology, Hugstetter Straße 55, D-79106 Freiburg, Germany. Electronic address: nina.berger@uniklinik-freiburg.de.
³ Department of Anesthesiology and Critical Care, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany; Laboratory of origin: Workgroup Clinical Respiration Physiology, Hugstetter Straße 55, D-79106 Freiburg, Germany. Electronic address: sara.lozano@uniklinik-freiburg.de.
⁴ Department of Anesthesiology and Critical Care, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany; Laboratory of origin: Workgroup Clinical Respiration Physiology, Hugstetter Straße 55, D-79106 Freiburg, Germany. Electronic address: steffen.wirth@uniklinik-freiburg.de.

PMID: 31546026
DOI: 10.1016/j.resp.2019.103303

Abstract

Flow Controlled Expiration (FLEX) has been demonstrated to be lungprotective in models of ARDS during controlled mechanical ventilation. However, modern ventilation strategies in critical care include spontaneous breathing. Therefore, we investigated breathing discomfort and potential performance constraints of FLEX in 24 healthy test persons under increased ventilation demand. The subjects generated 20, 50 or 100 W pedal power on a bicycle ergometer while breathing with and without FLEX and rated breathing discomfort on a scale ranging from 0 (comfortable) to 10 (not tolerable). Then the subjects were asked to indicate the power they could maintain for 30 min with and without FLEX. With FLEX, tidal volume was higher and respiratory rate lower than without. Breathing discomfort was slightly increased by FLEX (on average from 2.2 to 3.2, p = 0.002). The estimated maintainable power was similar with and without FLEX (p = 0.986). We conclude that FLEX does not intolerably increase breathing discomfort and does not impair physical performance.

Keywords: Breathing discomfort; Breathing support; Expiration; Lung stabilization; Perception; Ventilation therapy.

MeSH terms

Adult
Bicycling / physiology*
Exercise / physiology*
Exercise Test / methods*
Exhalation / physiology*
Female
Forced Expiratory Flow Rates / physiology*
Humans
Male
Middle Aged
Tidal Volume / physiology*
Young Adult