Which percussion finding is associated with hemothorax?

• A. Hyperresonance
• B. Dullness
• C. Hyperresonance/dullness
• D. Normal resonance

Answer: (C)

Percussion tones in the chest reflect what’s in the pleural space: air produces a hyperresonant sound, while fluid yields dullness. A hemothorax involves blood in the pleural space, so dullness would be expected. However, trauma can also cause air to be present in the chest (a pneumothorax) alongside blood, creating a hemopneumothorax. In that mixed situation, you can encounter dullness in areas where fluid sits and hyperresonance where air accumulates. That combination—hyperresonance with dullness—best accounts for the possible findings in a hemothorax, especially when a concurrent pneumothorax is present. Hyperresonance alone would point to air without fluid, dullness alone fits fluid without air, and normal resonance would not explain a pleural space problem.