What characterizes a resonant percussion note?

A resonant percussion note is characterized by a hollow sound that is considered normal in healthy lung tissue. This quality reflects the presence of air in the thoracic cavity and indicates that the underlying lung is well-aerated. When percussing the chest, a resonant note indicates that the lung tissue beneath is healthy and functioning properly, as it allows for the sound waves to resonate rather than being muffled or dampened.

In contrast, the other options illustrate different pathological conditions. A dull thudding sound suggests fluid or solid masses, indicating potential issues like pleural effusion or consolidation. A flat sound over atelectasis signifies that the lung has collapsed or is filled with fluid, which disrupts normal air-filled lung resonance. A booming sound over emphysema may suggest hyperinflation of the lungs, which can also affect the normal resonance of the percussion note.

Thus, the descriptor of a hollow sound aligns well with the characteristics of normal lung tissue, reinforcing that choice as the accurate representation of a resonant percussion note.