Ref: Chest Sounds

1. Property checklist
2. Fine crackles
3. Coarse crackles
4. Inspiratory stridor
5. Wheeze
6. Rhonchus
7. Bronchial breathing
8. Pleural rub

Property checklist

• Intensity
• Pitch
• Symmetrical vs. asymmetrical
• Localized vs. diffuse
• Inspiratory vs. expiratory
• Early vs. late
• Changes to each property during breathing cycle

Fine crackles

• Sound: fingernails over the teeth side of Velcro.
• Where: base of lung.
• Why: distal airway collapse on expiration.
• DDx:
  • Pulmonary fibrosis

Coarse crackles

• Sound: quickly popping bubblewrap bubbles.
• Where: R lower lobe.
• Why: distal airway collapse on expiration.
• DDx:
  • Resolving pneumonia
  • Pulmonary edema

Inspiratory stridor

• Sound: increasing pitch Darth Vader, during inspiration only.
• Where: trachea, during inspiration.
• Why: blocked airway.
• DDx:
  • Narrowed upper airway 2° to foreign body, laryngeal CA. 

 Wheeze

• Sound: cartoon snore, louder on expiration.
• Where: L lower lobe.
• Why: air passing through narrowed bronchi.
• DDx [pitch: bronchi size obstructed]:
  • Bronchial asthma [high pitch]
  • LVF

Rhonchus

• Sound: baritone, musical strumming sound.
• Where: R lower lobe, usually during breathing out.
• Why: air passing through narrowed bronchi.
• DDx:
  • Chronic bronchitis

Bronchial breathing

• Sound: similar to sound heard if listen to larynx.
• Where: L lower lobe [not the larynx!].
• Why: fibrosis, consolidation.
• DDx:
  • Pneumonia 

Pleural rub

• Sound: slow grating, then a thump.
• Where: R middle lobe.
• Why: inflamed pleura [visceral, parietal] moving over each other.
• DDx:
  • Pleurisy, 2° to pulmonary infarction, localized pneumonia
  • Spontaneous pneumothorax