ventilation graphs Flashcards
5 points of spirometer safety
-subject in could health
-medical grade equipment
-mouthpiece disinfected before and after use
-fresh soda lime so CO2 is removed quickly
-water level isn’t too high so it doesn’t enter breathing tubes
Describe apparatus of spirometer
-subject wears nose clip so air doesn’t escape or enter this way
-tube into subject’s mouth which enters chamber
-lid suspended in water to make chamber airtight
-pen and kymograph attached to lid
How does a spirometer work?
-subject breathes in and out until oxygen is used up
-CO2 removed when they exhale by soda lime
-lid moves up and down as subject breathes in/ out
-pen on kymograph draws a trace as the lid on the chamber moves
what is used to remove resistance for breathing?
counterbalance
What is tidal volume?
volume of air in each normal breath
How do you calculate tidal volume?
measure peak to trough on 3 waves and find mean
What is vital capacity?
biggest volume of breath in and out
How do you measure vital capacity?
peak to trough of biggest inhale/exhale
What is breathing rate?
How many breaths are take in 60 seconds
How do you measure breathing rate?
count number of peaks/troughs in 60 secs
What is total lung capacity?
volume of air in lungs following maximum inhalation
How do you calculate TLC?
vital capacity+residual volume
What is residual volume?
volume of air remaining in lungs after maximum forceful expiration
What is oxygen consumption?
rate at which oxygen is used up (dm3/min)
How do you calculate oxygen consumption?
decrease of oxygen (on y axis) in 1 minute6
