Term
| what is the mean pulmonary arterial pressure? |
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Definition
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Term
| characteristics of pulmonary circulatory system |
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Definition
low pressure
thin walls
highly compliant
very little smooth muscle
functions as a blood reservoir |
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Term
| characteristics of systemic circulation |
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Definition
high pressure (100mmHg)
regulated blood flow to organs
thick walls
non-compliant
lots of smooth muscle |
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Term
| Outflow pressure of pulmonary vs. systemic system |
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Definition
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Term
| Inflow pressures of pulmonary vs. systemic circulations |
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Definition
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Term
| Resistance in the pulmonary vasculature |
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Definition
very little change in resistance in response to large changes in vol. or flow
high compliance, low resistance system |
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Term
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Definition
usually atmospheric
if it's greater than capillary pressure, then you get capillary collapse |
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Term
| Transmural Pressure equation |
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Definition
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Term
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Definition
pulmonary capillaries
corner vessels |
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Term
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Definition
arteries & veins in parenchyma
radial traction pulls arteries & veins open |
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Term
| how is pulmonary vascular resistance affected by increases in pressure or flow? |
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Definition
| PVR actually decreases as pressure or flow increases |
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Term
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Definition
| clowed capillaries open as pressure decreases in the pulmonary circuit |
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Term
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Definition
| already open capillaries distend at higher pressures |
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Term
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Definition
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Term
| Distribution of blood flow in the pulmonary system |
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Definition
favors gravity, so blood flow increases linearly as you move from apex to base of the lung
dependent on posture |
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Term
| Alveoli surrounding the capillaries act as... |
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Definition
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Term
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Definition
Zone 1= Apex (PA>Pa>Pv)
Zone 2= middle region (Pa>PA>Pv)
Zone 3=Base (Pa>Pv>PA) |
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Term
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Definition
hypoxic pulmonary vasoconstriction
during hypoxic exposure, pulm. arterioles constrict to direct blood flow to better ventilated areas |
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Term
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Definition
15% of blood flow goes to lungs
HPV of whole lung so blood is shunted to the aorta vial ductus arteriosis |
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Term
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Definition
most potent endogenous vasodilator
produced in endothelial cell membrane
short half-life (<0.5 seconds) |
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Term
| Rapid flow through pulmonary vessel's effect on NO |
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Definition
| increases stress and stimulates NO synthase |
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Term
| Direction & amount of material filtered through capillary wall governed by: |
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Definition
chemical nature of material
size of particle
balance of forces on either side of capillary wall |
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