Lung Physiology Flashcards
1
Q
Why does pulmonary pressure not increase linearly with increases in CO?
A
Lung circulation has high compliance and additional capillaries are recruited as CO increases.
2
Q
Pulmonary Pressure Equation
A
dP=CO*SVR
3
Q
Determinants of Pulmonary Blood Flow (3)
A
Gravity: higher at bases
Hypoxia: low PO2 causes constriction to reduce flow to poorly ventilated areas.
Endogenous chemicals
4
Q
West Zones of Lung
A
Zone 1: PA>Pa>Pv; no perfusion
Zone 2: Pa>PA>Pv; perfusion fluctuates
Zone 3: Pa>Pv>PA; constant flow
5
Q
Starling’s Law of Flow
A
Flow=Kf[(Pmv-Pi)-o(Pimv-Pii)]
Where P is hydrostatic pressure and Pi is oncotic pressure. O is permeability coefficient (1 is complete?)
