During deep inspiration and expiration with the mouth open, we can assess the breath sounds using auscultation. These sounds are caused by resonance in the bronchial system during breathing and are audible during both inspiration and expiration.
During auscultation the following has to be assessed:
- The breath sounds, in terms of:
- Character (frequency and sharpness).
- Intensity of inspiration and expiration.
- Ratio of inspiration time and expiration time.
- The presence of adventitious sounds, always indicative of pathology.
- And, if indicated, bronchophony.