What is minimal volume?

What is minimal volume?

• A. Largest amount of air that can be forcibly exhaled.
• B. The amount of air that can be forcibly inhaled after normal inspiration.
• C. The amount of air that cannot be forcibly exhaled.
• D. Air remaining after residual volume.

Answer: (D)

Minimal volume is the smallest amount of air the lungs can contain, achieved when the lungs are collapsed to their smallest size with zero transpulmonary pressure. This corresponds to the air remaining after residual volume has been reached and the lungs are further compressed, such as when the chest is opened and the lungs collapse. That’s why the description “air remaining after residual volume” best fits minimal volume. The other terms refer to larger, distinct lung volumes: expiratory reserve is the extra air you can exhale after a normal breath, inspiratory reserve is the extra air you can inhale after a normal breath, and residual volume is the air left after a maximal exhale with the chest intact.

Minimal volume is the smallest amount of air the lungs can contain, achieved when the lungs are collapsed to their smallest size with zero transpulmonary pressure. This corresponds to the air remaining after residual volume has been reached and the lungs are further compressed, such as when the chest is opened and the lungs collapse. That’s why the description “air remaining after residual volume” best fits minimal volume. The other terms refer to larger, distinct lung volumes: expiratory reserve is the extra air you can exhale after a normal breath, inspiratory reserve is the extra air you can inhale after a normal breath, and residual volume is the air left after a maximal exhale with the chest intact.