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06:11
Employing the Forced Oscillation Technique for the Assessment of Respiratory Mechanics in Adults
Published on: February 9, 2022
Force oscillations simulating breathing maneuvers do not prevent force adaptation.
Chris Pascoe1, Yuekan Jiao, Chun Y Seow
1University of British Columbia, James Hogg Research Center, St. Paul’s Hospital Vancouver, Canada.
American Journal of Respiratory Cell and Molecular Biology
|February 11, 2012
Summary
Simulated breathing maneuvers did not prevent airway smooth muscle (ASM) force adaptation, even with induced tone. This suggests that force gain in ASM may occur in vivo, potentially contributing to airway hyperresponsiveness in asthma.
Area of Science:
- Physiology
- Respiratory Medicine
- Smooth Muscle Biology
Background:
- Asthma involves airway inflammation, leading to airway smooth muscle (ASM) exposure to spasmogens.
- Spasmogens increase ASM tone, potentially causing force adaptation.
- Breathing maneuvers can influence ASM force adaptation, but simulated conditions may be unphysiologic.
Purpose of the Study:
- To investigate if force adaptation occurs in ASM under simulated breathing conditions.
- To assess the impact of simulated tidal breathing and deep inspirations on ASM tone and force.
Main Methods:
- Applied force oscillations simulating breathing maneuvers to ASM.
- Induced ASM tone using carbachol.
- Assessed ASM force-generating capacity using electrical field stimulations (EFS).
Main Results:
- Force oscillations before tone induction had minimal effect on EFS-induced force.
- Carbachol-induced tone transiently decreased after deep inspiration and significantly declined with tidal oscillations.
- Simulated breathing maneuvers did not prevent ASM force adaptation.
Conclusions:
- Force adaptation in ASM may occur in vivo during breathing.
- This force gain could contribute to the development of airway hyperresponsiveness in asthma.
- Simulated breathing maneuvers do not inhibit ASM force adaptation.
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