In trauma, hyperresonance to percussion is most consistent with which diagnosis?

• A. Hyperresonance
• B. Dullness on percussion
• C. Increased fremitus
• D. Crackles

Answer: (A)

Hyperresonance on percussion means there is more air than normal in the chest. In the setting of trauma, that increased air in the pleural space points to a pneumothorax, where air has leaked into and between the lung and chest wall causing the lung to collapse. The extra air makes the percussion note louder and longer—a hyperresonant sound—on the affected side. Dullness on percussion would suggest fluid or solid tissue in the chest (like a pleural effusion or consolidation). Increased fremitus occurs with dense or fluid-filled lungs, not a pneumothorax, and crackles are abnormal lung sounds from fluid in the airways or alveoli, not a percussion finding. So the hyperresonant finding best fits pneumothorax in the trauma setting.