Measurement of Residual Volume Flashcards
1
Q
What is RV and how is it calculated?
A
Residual Volume = (Concentration 1/ Concentrated 2) X the volume of the spirometer
2
Q
Describe the helium method dilutio
A
When patient is asked to inhale they are connected to a spirometer of a specific volume which contains a known concentration of helium. As the air by the patient is breathed out, it dilutes the helium giving you a second concentration.
3
Q
What is the FRC, how is it measured and calculated?
A
Functional residual capacity. It is measured via the same process but instead of forced exhalation they patient is asked to breath out normally. The same calculation is then carried out.
