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Rigid external resistances cause effort dependent maximal expiratory and inspiratory flows

C F Melissant1, J W Lammers, M Demedts

  • 1Department of Pneumology, University Hospital Gasthuisberg, Leuven, Belgium.

American Journal of Respiratory and Critical Care Medicine
|November 1, 1995
PubMed
Summary

External resistances increase the ratio of maximal expiratory flow to maximal inspiratory flow (MEF50/MIF50) in healthy individuals. This finding challenges the classic concept of fixed upper airway obstruction, highlighting effort-dependency in flow limitation.

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