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PubMed · 2779183

Parametric evaluation of forced expiration using a numerical model.

D Elad·R D Kamm
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Abstract

Numerical calculations were performed to study the influence of several physiologic parameters on a forced expiration. It was found that the axial distribution of airway compliance produced profound changes in the detailed flow pattern, as characterized by the axial distributions of speed index and area ratio, but had little effect on the flow-volume curve. Similar results were obtained when the expression for frictional losses was changed to reflect new experimental results. In contrast, changes in airway size and geometry altered both the detailed flow pattern and the mean expiratory flow rate. The shape of the flow-volume curve remained unchanged.

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Forced Expiratory Flow RatesForced Expiratory VolumeLung ComplianceMathematicsModels, BiologicalPulmonary VentilationJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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D Elad, R D Kamm. 1989. Parametric evaluation of forced expiration using a numerical model.. https://doi.org/10.1115/1.3168365

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Expiratory flow limitation detected by forced oscillation and negative expiratory pressure.

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