Reference

Sound atlas

14 basic and adventitious respiratory sounds. On each card you can listen to the sound, see its waveform and spectrogram, and read about its mechanism and clinical meaning.

Basic breath sounds

The background of the examination. Always read adventitious sounds against this background.

Vesicular breath soundNormal breath sound

The soft, non-musical, broadband background sound over the peripheral lung fields.

InspiratoryNormal peripheral sound

Bronchovesicular breath soundBronchovesicular breathing

Between vesicular and bronchial. Inspiration and expiration are similar in length and intensity.

Both phasesNormal: central areas

Bronchial breathingTubular breathing (older term)

A loud, high-pitched sound. Expiration is at least as long as inspiration. It is normal over the manubrium (bronchial breath sound). Heard over the lung periphery, it is called bronchial breathing and is abnormal.

ExpiratoryConsolidation (over the periphery)

Tracheal breath soundTracheal breathing

A harsh, loud, broadband sound heard over the neck, with a prominent expiratory component.

Both phasesNormal: neck

Diminished / absent breath soundsReduced or absent air entry

A sound of normal character that is weak or not heard at all. One of the most important findings is the absence of a sound.

InspiratoryEffusion, pneumothorax, low flow

Continuous adventitious sounds

Musical or partly musical sounds that last longer than about 100 ms in the CORSA definition.

Monophonic wheezeSibilant rhonchus (older term)

A continuous, musical sound made up of one dominant tone.

ExpiratoryLocal narrowing (if fixed)

Polyphonic wheezeSibilant rhonchi (older term)

A musical sound in which several tones are heard at once. It occurs in widespread obstruction.

ExpiratoryAsthma, COPD

Random monophonic wheezesScattered short wheezes

Short single-tone wheezes at different pitches in each expiration; common in asthma.

ExpiratoryAsthma

RhonchusLow-pitched wheeze (CORSA) · sonorous rhonchus

A low-pitched continuous sound. In the CORSA definition it is below 300 Hz and longer than 100 ms. It is associated with secretions or narrowing in large airways.

ExpiratorySecretions

StridorLaryngeal or tracheal stridor

A continuous sound that arises from the larynx or a central airway and is loudest over the neck.

InspiratoryUpper airway narrowing

Discontinuous adventitious sounds

Brief, explosive, non-musical transients that last milliseconds.

Fine cracklesFine rales · crepitations (older terms)

Brief, high-pitched, explosive transient sounds, typically in mid-to-late inspiration. "Velcro" crackles.

InspiratoryFibrotic ILD, congestion

Coarse cracklesCoarse rales · crepitations (older terms)

Longer, lower-pitched and louder discontinuous sounds. They occur mostly in early-to-mid inspiration and may also be heard in expiration.

Both phasesBronchiectasis, secretions, pneumonia

Other sounds

Sounds that do not fit neatly into the continuous/discontinuous division.

SquawkSqueak · short wheeze

A brief, inspiratory, musical sound. A crackle-like burst often comes before it.

InspiratoryHypersensitivity pneumonitis, ILD

Pleural friction rubPleural rub · friction rub

A superficial, local, non-musical sound. It creaks, or resembles "creaking leather".

Both phasesPleurisy, infarction