What causes Hyperresonance in lungs?

Hyperresonant sounds may also be heard when percussing lungs hyperinflated with air, such as may occur in patients with COPD, or patients having an acute asthmatic attack. An area of hyperresonance on one side of the chest may indicate a pneumothorax. Tympanic sounds are hollow, high, drumlike sounds.

What does Hyperresonance percussion mean?

hy·per·res·o·nance

(hī'pĕr-rez'ō-nans), 1. An extreme degree of resonance. 2. Resonance increased above the normal, and often of lower pitch, on percussion of an area of the body; occurs in the chest as a result of overinflation of the lung as in emphysema or pneumothorax and in the abdomen over distended bowel.