Lung Volumes, flow and ventilation: Lecture 7 Flashcards
(55 cards)
What is restrictive disease?
- they have a stiff or scarred lung
- they have smaller/restrictive lung capacity
- THIS LIMITS THE LUNGS VOLUME
What are the 2 causes of a restrictive disease?
- pulmonary fibrosis (thickening of elastic tissue)
- neuromuscular disorder
how do we measure lung volume and capacities?
we look at the change in air volume that is displaced by inspiration and expiration
- via spirometer
True or False
The change in volume is a function of time, in reference to flow
True
What is Tidal Volume? (Vt)
the volume of air entering or leaving the lungs during one breath
- average value under resting conditions
What is Inspiratory reserve volume? (IRV)
EXTRA volume that can be maximally inspired over the above typical resting tidal volume
What is Inspiratory capacity? (IC)
Max volume that can be inspired
- starting from the end of a normal expiration
(IC = IRV + VT)
What is Expiratory reserve volume? (ERV)
Max volume that can be actively expired starting from the end of a typical resting tidal volume
How do we measure ventilation?
via a spirometer
True or False
Do taller people have bigger lungs?
True
Will we always have a residual volume?
yes, if we have healthy lungs
What is the functional capacity that we have control over? aka doing a big breath in or out
Vital capacity
What are examples of neuromuscular disorders?
- polio
- amyotrophic lateral sclerosis (ALS)
- muscular dystrophy
What does a spirogram do?
tracks the change in volume
True or False
There is 21% oxygen
True
What is Residual Volume?
the volume of air remaining in the lungs after a maximal expiration
True or False
Residual lung volume is about 1/4 of your total lung capacity give or take
True
What is Function residual capacity? (FRC)
the volume of air in the lungs at the end of a normal passive expiration
(FRC = ERV +RV)
What is Vital capacity? (VC)
max volume of air that can be moved out during a one-breath after a maximum inspiration
(VC = IRV + VT + ERV)
What is Total lung capacity?
max volume of air that the lungs can hold
(TLC= VC +RV)
True or False
The TLC, VC and RV are typically fixed numbers
True
From a respiratory mechanics point of view, what does the FRC represent?
natural relaxation volume of the respiratory system
- volume where there is a balance between the outwards chest wall forces and the inwards elastic recoil forces of the lung
The FRC is what two volumes put together?
Expiratory reserve volume ERV + Residual volume RV
What will the FRC plus the total lung capacity be?
Inspiratory capacity IC