Stethacoustic nomenclature of lung sounds: towards a worldwide consensus.

In order to found the stethacoustic nomenclature on objective facts, we suggest to express lung sounds in a way taking first into account acoustical physics. Indeed the physicoacoustical definition of lung sounds has to take place before its psychoacoustical definition. Acoustical physics identifies only Sour kinds of vibrations: simple and complex periodical vibrations, transient and continuous non periodical vibrations. Lung sounds are bound to fall into one of those falls categories. Phonopneumograms in time and frequency domain allow an objective classification of breath and adventitious lung sounds and introduce a simplification into the nomenclature which recognizes only four sorts of lung sounds, all of them included in these two categories: 1 degrees breath sounds include normal and bronchial breath sounds, 2 degrees adventitious sounds include crackles (for every discontinuous sound) and wheezes (for every continuous sound). Objective parameters add their specific characteristics in terms of pitch, complexity, Hz-frequency, timing in the respiratory cycle and duration. The proposal of a new nomenclature is justified because it is supported by measurable physical phenomena. The solution of semantic problems should enable clinicians to progress toward a worldwide consensus.