Physiology: lung volumes & capacities Flashcards
what is the tidal volume(TV)
the volume of air leaving or entering the lungs with each breath
what is the inspiratory reserve volume(IRV)
extra volume of air that can be inspired over and above the typical resting tidal volume
what is the expiratory reserve volume(ERV)
extra volume of air that can be actively expired by maximal contraction beyond normal volume of air after resting tidal volume
what is the residual volume(RV)
minimum volume of air remaining in lungs even after maximal expiration
what is the inspiratory capacity(IC)
maximum volume of air that can be inspired at end of normal quiet expiration
how does inspiratory capacity relate to lung volumes
IC = TV + IRV
what is the functional residual capacity(FRC)
volume of air in lungs after normal passive expiration
how does the functional residual capacity relate to lung volumes
FRC = ERV + RV
what is the vital capacity
maximum volume of air that can be moved out during a single breath following a maximal inspiration
how does vital capacity relate to lung volumes
VC = IRV + TV + ERV
what is the total lung capacity
total volume of air the lungs can hold
what can total lung capacity be broken up into
TLC = VC + RV
why cant total lung capacity be measured by spirometry
because the residual volume cant be measured by spirometry
what can cause the residual volume to increase
when elastic recoil of lungs is lost(e.g. emphysema)
