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PubMed · 2780524

[Optimizing monofrequent oscillometry].

H J Smith·J Vogel·U Smidt·I Issa·A Barleben·E Pleger
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Abstract

Against the background of the working hypothesis of the 1-parametric Siregnost FD 5 forced oscillation technique-phase angle psi may be invariant in a clinical reference population-the hypothetical straight Ros-P line is in good agreement with the crowd of extremely nonlinear Rre-P-lines only within narrow limits. Neglecting phase angle measurements it might be useful to insert a known linear resistor into the airway to determine the pertaining Rre-P relation. In spite of selective tuning to the oscillation frequency of 10 Hz there is full sensitivity to stationary flow; alinear stationary flow characteristics of resistors can be readily determined by forced oscillation. There is a marked improvement in the P-psi/Rre-phi-evaluating system with respect both to the symmetry of phase angle and unequivocality of pressure when the reference phase angle alpha is shifted from 81 degrees to 0 degrees. Using digital data acquisition and processing, a flexible evaluation technique with monitor-oriented test management, automatical calculation of secondary values and multidimensional presentation of results on a graphical display is provided, which has proved its worth in experimental and clinical-physiological studies.

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Airway ResistanceHumansLung Diseases, ObstructiveMicrocomputersModels, BiologicalOscillometrySignal Processing, Computer-AssistedEnglish AbstractJournal Article

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H J Smith, J Vogel, U Smidt, I Issa, A Barleben, E Pleger. 1989. [Optimizing monofrequent oscillometry].. https://pubmed.ncbi.nlm.nih.gov/2780524/

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