Chest Signs by Pathology

Expansion

Percussion note, breath sounds and vocal resonance identify the pathology

Mnemonic

Combine the four findings and each pathology has a unique signature:

Pathology	Expansion	Percussion	Breath sounds	Vocal resonance
Consolidation	Reduced	Dull	Bronchial	Increased
Effusion	Reduced	Stony dull	Reduced or absent	Reduced
Pneumothorax	Reduced	Hyperresonant	Reduced or absent	Reduced
Collapse	Reduced	Dull	Reduced	Reduced
Fibrosis	Reduced	Normal or dull	Bronchial, fine crackles	Increased

“Only consolidation and fibrosis increase vocal resonance”, because only solid lung conducts sound better; air and fluid both conduct it worse.

The trachea then separates the whole hemithorax causes: pushed away by a tension pneumothorax or large effusion, pulled towards by collapse or fibrosis.

“Stony dullness is essentially specific to an effusion”, whereas ordinary dullness has many causes.

Expansion

Condition	Trachea	Expansion	Percussion	Breath sounds	Vocal resonance
Consolidation	Central	Reduced	Dull	Bronchial	Increased
Pleural effusion	Away if large	Reduced	Stony dull	Reduced or absent	Reduced
Pneumothorax	Away if tension	Reduced	Hyperresonant	Reduced	Reduced
Collapse	Towards	Reduced	Dull	Reduced	Reduced
Fibrosis	Towards if localised	Reduced	Normal or dull	Bronchial, fine crackles	Increased
COPD	Central	Reduced, symmetrical	Hyperresonant	Quiet, wheeze	Normal

Two discriminations do most of the work:

Dull with increased vocal resonance means consolidation; stony dull with reduced resonance means effusion
Trachea towards the lesion means volume loss (collapse, fibrosis); away means volume gain (large effusion, tension pneumothorax)

Added sounds: coarse crackles that change with coughing suggest secretions; fine end-inspiratory crackles that do not suggest fibrosis or oedema; wheeze indicates airway narrowing; a pleural rub indicates pleural inflammation.

Bronchial breathing is heard when consolidated lung conducts sound from the large airways to the chest wall.