3.1.4 spirometer Flashcards
breathing rate def
number of breaths per minute
oxygen uptake
the volume of oxygen absorbed b7 the lungs in one minute
tidal volume
the volume of air inhaled or exhaled in one breath , measured at rest
vital capacity
max volume of air inhaled/exhaled in one breath
spirometer precautions (5)
- subject healthy and free from asthma
- soda lime fresh and functioning
- no air leaks in the apparatus , as this would give invalid or inaccurate results
- mouthpiece should be DISINFECTED
- water chamber use not be overfilled (or water may enter the air tubes)
- ENOUGH OXYGEN
how to measure vital capacity
- take a deep breath and expire all air possible from the lungs
what does vital capacity depend on
- size of person(particularly height)
- their age and gender
- level of regular exercise
usual vital capacity
2.5-5 dm3
residual volume
volume of air left in lungs after forced expiration
- remains in airways and alveoli - approx 1.5dm3
tidal volume
- volume of air moved in and out with each breath
- measured at rest
- typical is 0.5dm3
-usually sufficient to supply all the oxygen required in the body at rest
purpose of breathing
- supplies oxygen for respiration and removes carbon dioxide produced in respiration
purpose of soda lime
- absorbs carbon dioxide
- so that the volume of air in the chamber decreases
- measure of oxygen consumption
how to measure breathing rate
count number of peaks per minute
increased oxygen uptake will result from
- increased breathing rate
- deeper breaths
air in the chamber inspiration
- lid moves down, reocrded on a data logger
- air drawn from the chamber
assumption w soda lime
- vol co2 released and absorbed by soda lime = vol o2 absorbed by blood
spirometer controls
- all same fitness
- all same respiratory health
- same mass
describe how to measure tidal volume
- nose clip
- healthy volunteer
- mouth on disinfected mouthpiece
- breathe regularly over a minute
- vol chamber decreases as breathe in, data logged on trace
- measure from peak to trough