Alveolar Gas Exchange Flashcards
What is the principle function of the lungs and thorax?
respiration
What does gas exchange depend on?
ventilation, profusion, barriers (air-liquid interface)
The lung gas exchange begins at the level of (blank)
respiratory bronchiole
What does fick’s law tells us?
diffusion is proportional to surface area and inversely proportional to thickness of surface
In normal lungs is greater at the (Blank) and becomes progressively less towards the (blank).
In supine position this effect is (blank(
base
apex
less
Intrapleural pressure is more negative at the (blank) or compared to the bottom
top
The change in ventiliation per unit volume is greater at the (blank) than the (blank).
base
apex
Blood flow decreases from the (blank) as compared to ventilation which is less step but still decreases from (blank) of lung
bottom to the top
bottom to top
In the upright position there is a linear decrease of blood flow from the base to the apex, and (blank) from hilum to outer peripheral lung near pleura.
decreases
It is the alteration and abnormalities of the V/q rations that causes what?
hypoxia and disease states (ideal is v=q or a v/q=1)
What is the normal range of PaO2 (arterial)
70-100
Is PAO2 equal to PaO2?
no
decreased PaO2= (blank)
hypoxemia
What are basic causes of hypoxemia?
decreased PAO2 hypoventilation reduced FiO2 or low atmospheric pressure venitlation-perfusion mismatch diffusion defects right to left shunt
The higher the altitude the lower the (blank)
barometric pressure and PIO2