NU 503 Circulation MASTERY GUIDE
(2024): 200+ Q&A, Diagrams &
Mnemonics – A+ Guaranteed.
oxygenated blood to left atrium via pulmonary veins
oxygenate blood and remove carbon dioxide
pulmonary circulation origination
right ventricle via pulmonary artery
Systemic Circulation
starts with aorta receiving output from LV
Systemic circulation output with exercise
varies greatly to skin and skeletal muscles
Systemic vs pulmonary pressure
systemic 5-10x higher than pulmonary
Blood flow with heavy exercise
Significantly increase blood flow from 5 L/min to 25L/min
Decreases blood flow to all other organs but the heart (heart blood flow increases with exercise)
Blood vessel structure layers
1. tunica intima
2. tunica media
3. tunica externa
Tunica intima
vital to vascular health, single innermost layer of vessel and creates vessel lining, basement
membrane, and elastic fibers
Tunica media
middle vessel layer, concentric layers of vascular smooth muscle cells. Surrounding smooth muscle is
another layer of elastic fibers
Tunica externa
outermost layer: strong connective tissue that keeps vessels intact
Artery walls
much thicker for higher pressures, highest in aorta
Artery branching
Branch into smaller vessels (arterioles 80% SVR) extending from heart
Decrease in lumen diameter
, Decrease in elastic fibers
Increase in relative amount of smooth muscle
Capillaries function
Exchange between blood and tissues
capillaries vasculature
thin walls of endothelial cells and basement membrane
capillary blood flow
collected into venules and larger veins
Law of LaPlace
biophysics of vascular wall tension
hydrostatic pressure: aorta
created by blood pumped into aorta
wall tension created by
hydrostatic pressure- push on vessel wall
Wall tension
contributor to rupturing of weakened vessel
what increases vascular wall tension?
blood pressure
radius of vessel
What decreases vascular wall tension?
increased wall thickness
Vascular Aneurysm: Law of LaPlace
weakened vessel is dilates and radius increases and increased wall tension, creates vessel
enlargement over time, increasing risk of catastrophic rupture
Aneurysm risk factors
congenital, atherosclerosis, hypertension, diabetes, tobacco, age >65, men
Law of laplace formula
T = (P x r) / h
T = (P x r) / h
T = tension of wall
P = pressure in vessel wall
r = radius of vessel
h = thickness of vessel
(2024): 200+ Q&A, Diagrams &
Mnemonics – A+ Guaranteed.
oxygenated blood to left atrium via pulmonary veins
oxygenate blood and remove carbon dioxide
pulmonary circulation origination
right ventricle via pulmonary artery
Systemic Circulation
starts with aorta receiving output from LV
Systemic circulation output with exercise
varies greatly to skin and skeletal muscles
Systemic vs pulmonary pressure
systemic 5-10x higher than pulmonary
Blood flow with heavy exercise
Significantly increase blood flow from 5 L/min to 25L/min
Decreases blood flow to all other organs but the heart (heart blood flow increases with exercise)
Blood vessel structure layers
1. tunica intima
2. tunica media
3. tunica externa
Tunica intima
vital to vascular health, single innermost layer of vessel and creates vessel lining, basement
membrane, and elastic fibers
Tunica media
middle vessel layer, concentric layers of vascular smooth muscle cells. Surrounding smooth muscle is
another layer of elastic fibers
Tunica externa
outermost layer: strong connective tissue that keeps vessels intact
Artery walls
much thicker for higher pressures, highest in aorta
Artery branching
Branch into smaller vessels (arterioles 80% SVR) extending from heart
Decrease in lumen diameter
, Decrease in elastic fibers
Increase in relative amount of smooth muscle
Capillaries function
Exchange between blood and tissues
capillaries vasculature
thin walls of endothelial cells and basement membrane
capillary blood flow
collected into venules and larger veins
Law of LaPlace
biophysics of vascular wall tension
hydrostatic pressure: aorta
created by blood pumped into aorta
wall tension created by
hydrostatic pressure- push on vessel wall
Wall tension
contributor to rupturing of weakened vessel
what increases vascular wall tension?
blood pressure
radius of vessel
What decreases vascular wall tension?
increased wall thickness
Vascular Aneurysm: Law of LaPlace
weakened vessel is dilates and radius increases and increased wall tension, creates vessel
enlargement over time, increasing risk of catastrophic rupture
Aneurysm risk factors
congenital, atherosclerosis, hypertension, diabetes, tobacco, age >65, men
Law of laplace formula
T = (P x r) / h
T = (P x r) / h
T = tension of wall
P = pressure in vessel wall
r = radius of vessel
h = thickness of vessel
