Which of the following techniques are used to measure residual volume?
I.helium dilution
II.body plethysmography
III.nitrogen washout
IV.flow-volume loops

Question

Quizplus · Accepted Answer

Residual volume, which is the volume of air remaining in the lungs after a maximal exhalation, cannot be measured directly by spirometry. Techniques like helium dilution, body plethysmography, and nitrogen washout are used to measure lung volumes that cannot be directly measured, including the residual volume. Flow-volume loops are used to assess the pattern of air movement in and out of the lungs during forced breathing maneuvers but do not measure lung volumes such as the residual volume directly.

Which of the Following Techniques Are Used to Measure Residual