[Analysis of transmission of continuous adventitious lung sounds in asthmatic patients--a comparison with continuous sounds due to bronchial stenosis].

We studied the acoustic features of continuous adventitious lung sounds in asthmatic patients, and analyzed the characteristics of transmission by comparing the continuous sounds in asthmatic patients with those due to bronchial stenosis. The results were as follows. 1) Continuous adventitious lung sounds in patients with bronchial stenosis confirmed by bronchoscopy were well transmitted to the neck over the trachea. Therefore, it was demonstrated that continuous adventitious lung sounds generated in the lung are able to be transmitted to the tracheal region. 2) Continuous adventitious lung sounds in asthmatic patients were divided into monophonic tones and polyphonic tones, according to sound spectrographic findings. From the results of the coherence analysis, the monophonic tones were considered to be generated in the right or left lung, and were well transmitted to the neck over the trachea. The origin of the polyphonic tones was unknown, but they were also relatively well transmitted to the neck over the trachea. It was confirmed that the tracheal region is a very important location for auscultating and monitoring asthmatic patients.