METHOD FOR DIAGNOSING BRONCHIAL PATENCY DISORDERS Russian patent published in 2003 - IPC

FIELD: medicine. SUBSTANCE: method involves recording respiration noise in trachea when carrying out forced expiration exercise. The noise process is plotted as spectrum time dependence. Forced expiration whistle is determined within frequency bandwidth of 400-600 Hz and high frequency whistles during the whole exercise and at its end. Forced expiration whistle duration is determined in frequency bandwidth of 400-600 Hz and compared to a threshold value. General duration of noise process is additionally determined. Bronchial patency disorder is diagnosed from general duration of noise process overcoming individual threshold value of 2.4* dFLVC /dPVR or force expiration whistle duration in frequency bandwidth of 400-600 Hz overcoming individual threshold value of 1.0* dFLVC /dMVC50. High frequency whistle during the whole exercise or at its end being detected in bandwidth higher than 600 Hz, bronchial patency disorder is diagnosed from general duration of noise process overcoming individual threshold value of 2.1* dFLVC /dPVR or force expiration whistle duration in frequency bandwidth of 400-600 Hz overcoming individual threshold value of 0.9*dFLVC /dMVC50, where dFLVC /dPVR is the due values of Forced Lung Vital Capacity, Peak Voluminous Rate of forced expiration and Voluminous Rate of forced expiration at 50% of FLVC after R. F. Clement. EFFECT: enhanced effectiveness in detecting bronchial patency disorders before clinical manifestations become detectable. 8 dwg