Phys 6 Respiratory mechanics Flashcards
What happens in a test where lungs are in a container and we have negative pressure in the container?
explain how the plotting of the volume change in relationship to negative pressure would look like in a pressure/volume relationship
At low volumes do you need higher or lower change in pressure to increase volume?
At middle ranges do we need more or less pressure difference to change the volume of the lungs?
At high volumes do you need higher or lower pressure change to change the volume?
What is the stretchability of the lungs measured as?
what is the equation?
what happens to the volume/pressure relationship when we exhale?
What different between air inflation and saline infation?
Difference in inspiratory and expiratory lines due to what?
what is this difference called?
what accounts for hysteresis in saline-filled curve?
Volume vs Airway pressure graph
how would the lungs look on this graph?
without the rib cage what would the resting point be?
Airway pressure/volume graph
how would the rib cage alone look like?
Airway pressure/volume graph
what about the line for lungs and rib cage when combined?
Airway pressure/volume graph
at what point do the lungs and rib cage exactly balance each other out?
Functional residual capacity
Airway pressure/volume graph
Lungs want to be where?
why cant they get there?
Airway pressure/volume graph
balance point for the rib cage
(also side note about pneumothoraxs)
What is FEV?
What is the amount of air that can be exhaled in the first second?
what ratio is important in testing pulmonary functions?
FVC- forced vital capacity (how much you can get out)
what is reduced in emphysema or asthma?
what type of diseases are these?
what happens to FEV1/FVC?
what is happening to either value?
what is reduced in interstitial lung disease?
what type of disease is this?
what happens to the FEV1/FVC ratio?
What does the elastic recoil of the lung want to happen?
why doesn’t this happen?
Elastic recoil would normally create collapse of the small airways and alveoli.
when opposing each other and not collapsing this is called interdependence
What happens if we lose some of the walls in the lung? (interdependence)
COPD
what happens if we increase airway resistance?
what does the blue represent?
What is the checkered part?
what does increasing resistance do to inspiratory loop? expiratory?
increase airway resistance can make the inpiratory loop bigger so inspiratory work is harder
at what point does expiration have to be active?
