Respiratory Physiology Lecture 2 part 8: Lung Volumes and Capacities Flashcards
What is spirometry apparatus used for?
The spirometer is an apparatus used for measuring the volume of air inspired and expired by the lungs
- It records the amount and the rate of air that you breathe in and out over a period of time
Spirometry
Pulmonary function test to determine the amount and the rate of inspired and expired air
What are the lung volumes?
- tidal volume
- inspiratory reserve volume
- expiratory reserve volume
- residual volume
What are the lung capacities?
- vital capacity
- inspiratory capacity
- function residual capacity
- total lung capacity
Atelectasis
complete or partial collapse of a lung or lobe of a lung; develops when alveoli become deflated/collapse
TV
Tidal volume
tidal volume
TV
the volume of air moved IN OR OUT of the respiratory tract (Breathed) during each ventilatory cycle.
IRV
Inspiratory Reserve Volume
Inspiratory Reserve Volume
IRV
the additional volume of air that can be forcibly inhaled following a normal inspiration. It can be accessed simply by inspiring maximally, to the Maximum Possible Inspiration.
ERV
Expiratory Reserve Volume
Expiratory Reserve Volume
ERV
the additional volume of air that can be forcibly exhaled following a normal expiration. It can be accessed simply by expiring maximally to the Maximum Voluntary Expiration.
RV
Residual Volume
Residual Volume
the volume of air remaining in the lungs after a Maximal Expiration. It cannot be expired no matter how vigorous or long the effort.
What lung volume cannot be measured by spiometry?
RV cannot be measured with a spirometry test.
RV = FRC - ERV.
Lung capacity
correspond to the SUM of 2 or more lung volumes
What are the lung capacities?
- vital capacity
- inspiratory capacity
- functional residual capacity
- total lung capacity
VC
Vital Capacity
Vital Capacity
VC
the maximal volume of air that can be forcibly exhaled after a Maximal Inspiration.
What volumes equal VC?
VC = TV + IRV + ERV
IC
Inspiratory capacity
Inspiratory capacity
IC
the maximal volume of air that can be forcibly inhaled.
What volumes equal IC?
IC = TV + IRV
FRC
Functional Residual Capacity
Functional Residual Capacity
the volume of air remaining in the lungs at the end of a normal expiration
What volumes equal FRC?
FRC = RV + ERV
TLC
Total Lung Capacity
Total Lung Capacity
the volume of air in the lungs at the end of a Maximal Inspiration.
What volumes equal TLC?
TLC = FRC + TV + IRV = VC + RV
What cannot be measured by spirometry test?
Residual volume (And consequently FRC and TLC) cannot be measured by means of simple spirometry test
