Question

What would you need to know or measure in order to determine the residual volume of the patient described ?

Please give a short answer.

Answer 1

Residual volume (RV) is the amount of air that remains in the lungs after maximum exhalation.It is normal to have some amount of air present to avoid lung from collapsing. On average, patient RV is about a liter. Doctors use some test to measure the residual air to check how the lungs are functioning. There are two different test:

1. Plethysmography: This test measure the total amount of air present in the lung. The patient sits inside the airtight booth called plethysmography and breathe through a mouthpiece while the air flow and pressure are collected.

2. Gas dilution test: This test measure how the concentration of gases in the container changes. The patient breathe from a comntainer having gas (100% oxygen or certain amount ofhelium in air).