What percussion note is expected in patients with emphysema?

In patients with emphysema, a hyper-resonant percussion note is expected due to the presence of increased air within the lungs. Emphysema is characterized by the destruction of alveolar walls and the loss of elastic recoil, which leads to air trapping and over-inflation of the lungs. As a result, there is an increased amount of air in the thoracic cavity, which causes a more resonant sound when the chest is percussed.

This hyper-resonance is distinct from other percussion notes you might encounter in clinical practice. A dull note would suggest denser tissue or fluid, which is typically associated with conditions such as pneumonia or pleural effusion. A normal note indicates healthy lung tissue, while a flat note is usually heard over areas of increased density like muscle or bone. Therefore, the presence of a hyper-resonant percussion note in a patient with emphysema aligns with the pathophysiological changes associated with the disease.