Abnormal breath sounds

Breath sounds are an important part of respiratory assessment and are usually assessed by the respiratory team.

Sound Characteristic Signs of
Wheezing Whistling sound, generally heard on expiration Asthma and airway obstruction
Stridor Snoring sound heard on inspiration Typical of obstruction, sputum plug or foreign body, anaphylactic reaction
Crackles A crackling or popping sound Collapsed alveoli popping open on inspiration
Rhonchi Snoring or rattling sounds Fluid partly blocking the bronchi; generally heard on expiration
Pleural friction A grating or rubbing sound heard on inspiration and expiration Indicative of pleural inflammation