Spirometers Flashcards
how many ways are there to measure breathing
4
Vital capacity
The maximum volume of air that can be breathed in or out in one breath
Tidal volume
The volume of air breathed in and out at rest
Breathing rate
this is the number of breaths taken in one minute
Oxygen uptake
this is the volume of oxygen used up by someone in a given time
How do we measure breathing?
a spirometer
What absorbs the waste CO2
soda-lime
Why does the CO2 need to be absorbed?
to stop the concentration of carbon dioxide in the re-breathed air from getting too high, as this can cause respiratory distress
What happens as the subject breathes through the spirometer
a trace is drawn on a rotating drum of paper or a graph is formed digitally, which can be viewed on a computer
what can be calculated from the spirometer trace?
vital capacity, tidal volume and breathing rate
how is oxygen uptake measured from the spirometer?
Carbon dioxide is removed from the exhaled air, meaning that the total volume of air available in the spirometer gradually decreases, as oxygen is extracted from it by the subject’s breathing. This change in volume is used as a measure of oxygen uptake
residual volume
The volume of air left in lungs after maximum expiration.
