resp-2 volumes and capacities Flashcards
what is spirometry
pulmonary function test to determine the amount and the rate of inspired and expired air
what is tidal volume
TV
volume of air moved in or out of the resp. tract during each ventilatory cycle
what is inspiratory reserve volume (IRV)
additional volume of air that can be forcibly inhaled following a normal inspiration, max inspiration
expiratory reserve volume (ERV)
additional volume of air that can be forcibly exhaled following a normal expiration, max voluntary expiration
residual volume (RV)
volume of air remaining in the lungs after a max expiration
can residual volume be measured with spirometry test
nooooo
how to measure residual volume (formula)
RV=FRC-ERV
=functional residual capacity-expiratory reserve volume
how to measure capacities? aka, what do they correspond to?
the sum of 2 or more lung volumes
vital capacity definition
the max volume that can be forcibly exhaled after a max inspiration
vital capacity formula
tidal volume+inspiratory reserve volume+expiratory reserve volume
inspiratory capacity definition
max volume of air that can be forcibly inhaled
Inspiratory capacity formula
tidal volume+ inspiratory reserve volume
functional residual capacity definition
volume of air remaining in the lungs at the endo f a normal expiration
functional residual capacity formula
residual volume+ expiratory reserve volume
total lung capacity definition
the volume of air in the lungs after a max inspiration
what is the anatomic dead space
the air that doesn’t get refreshed or used, breathed in but not available for gas exchange and moves out
minute total ventilation formula
tidal volume x resp. frequency
what is alveolar ventilation
amount of air moved into the alveoli per minute
it depends on the anatomical dead space!
is alveolar ventical or minute ventilation biiger
minute ventilation
is anatomical dead space constant
yes, constant regardless of breath size
alveolar ventilation volume
(tidal volume-anatomical dead space)x frequency
is increasing rate or depth better for increasing alveolar ventilation
increase depth
what is FEV1
forced expiratory volume in one second
what is FVC
forced vital capacity
total amount of air blown out in one breath after max inspiration as fast as possible
what does FVC equal
vital capacity
TV + IRV + ERV
what is FEV1/FVC
proportion of the amount of air that is blown out in 1 second
where is the difficulty in the obstructive pattern of breathing
difficulty in exhaling all of the air from the lungs, slower exhale, lots of air may remain in the lungs
what kind of diseases have obstructive pattern
CF, asthma
is FEV1 or FVC reduced in obstructive patterns
FEV1 significantly, FVC normal or reduced
what happens to FEV1/FCV in obstructive patter
reduced, <0.7
where is the difficulty in the restrictive pattern of breathing
they cannot fully fill their lungs with air
why does restrictive pattern happened
stuff lungs
what kind of diseases show restrictive pattern
lung fibrosis, scarring of lung tissue, muscular dystrophy
is FEV1 or FVC reduced in restrictive patterns
both
reduced vital capacity
what happens to FEV1/FCV in restrictive patter
almost normal!
they can breathe out fine, just not much air to begin with
what do they measure using helium
functional residual capacity (rv+ erv) bu measuring dilution concentrations
v2=v1(c1-c2)/c2
