Synopsis of tracheal sounds

A review is presented of the latest progress in studies of tracheal sounds. In particular, characterization of respiratory and heart-valve sounds to explore and develop automated methods for analysis and diagnosis of pulmonary insufficiency, cardiac, and neurological information is presented. Results from these studies indicate that automated analysis of pulmonary pathology is possible but not without impediments. The mean frequency of respiratory sound spectra is linearly related to respiratory flow rates less than 1 l/s. Respiratory sound spectral estimates are affected by heart-valve sounds, which could adversely affect results of discriminant analysis for patient classification. Static lung volume affects heart-valve sound spectra.<>