Peak frequency of tracheal forced expiratory wheezes during bronhodilatation test
Safronova, M.A.; Pochekutova, I.A.; Korenbaum, V.I.
Fiziologiia Cheloveka 40(6): 123-128
2014
ISSN/ISBN: 0131-1646 PMID: 25711115 Document Number: 673351
The response of peak frequencies of the most powerful tracheal forced expiratory wheezes (FEWs) and volumetric flow rates was experimentally evaluated under influence of bronhodilatation test in representative samples of 71 healthy volunteers and 69 patients with reversible bronchial obstruction. Lack of response of FEWs peak frequency in the middle of forced expiratory maneuver was found in patients, while significant reduction of FEWs peak frequency was characteristic for healthy volunteers. The response of peak value of mid-frequency (400-600 Hz) and early high-frequency (>600 Hz) FEWs observed in the middle of forced expiratory maneuver can be interpreted in favor of forced flow mechanism production of these respiratory sounds. The behaviour is consistent with the predictions of the vortex shedding model. Response of peak frequency of late high-frequency (>600 Hz) FEWs indicates the possibility of auto-oscillatory mechanism (independent on flow) involvement in formation of these respiratory sounds.