Cardiovascular System: Peripheral Circulation And Regulation

Front 1

What are the 5 functions of the peripheral circulation?

Back 1

1. Carries Blood

2. Exchange nutrients, waste, gas exchange

3. Transports substances : hormones, immune sys., enzymes

4. Helps regulate blood pressure

5. Direct blood flow to tissues

Front 2

What are large elastic arteries like?

Back 2

lots of elastic

small amounts of smooth muscle

Front 3

What are small elastic arteries like?

Back 3

less elastic

more smooth muscles

Front 4

What type of arteries have the thinnest walls?

Back 4

capillaries

Front 5

What are the 3 types of arteries?

Back 5

1. elastic

2. muscular

3. arterioles (then capillaries)

Front 6

What are the differences between arteries and veins?

Back 6

veins are:

thinner

less elastic

less smooth muscle

have valves

Front 7

Describe smallest to largest veins

Back 7

venules

small veins

medium or large veins

Front 8

What is the endothelium lining of capillaries continuous with?

Back 8

The endocardium of the heart

Front 9

what are pericapillary cells?

Back 9

cells that are intersperced and between endothelial cells and basement membranes

(fibroblasts, macrophages, undifferentiated smooth muscle)

Front 10

What are the 3 types of capillaries?

Back 10

1. Continuous

2. Fenestrated

3. Sinusoidal

Front 11

Describe continuous capillaries

Back 11

no gaps

less permeable to large molecules

found in muscles, nervous and many other

Front 12

Describe fenestrated capillaries

Back 12

means 'windows'

highly permeable

may or may not have diaphragm

found in intestinal villi, cilliary processes of the eye, choiroid plexuses of CNS, glomeruli (kidneys)

Front 13

Describe sinusoidal capillaries

Back 13

largest in diameter

have a lot of gaps

little or no basement membrane

permeable to large molecules

found in the endocrine glands

Front 14

What are sinusoids?

Back 14

large diameter sinusoidal capillaries

found in liver and bone marrow

Front 15

How do substances diffuse through capillaries?

Back 15

1. between endothelial cells

2. through fenestrae

3. through the plasma membrane

Front 16

What are venous sinuses?

Back 16

like sinusoidal capillaries but biggerj

found in spleen primarily

Front 17

What type of molecules readily diffuse across the plasma membrane?

Back 17

Lipid soluable

small H2O soluable

Front 18

What types of substances do NOT go out of the capillaries?

Back 18

RBC's,

lg H2O soluable (proteins)

Front 19

Describe how blood flows from arteriole through a capillary network

Back 19

1. arteriole

2. metarterioles

3. thoroughfare channel

4. precapillary sphincters

5. venous capillaries

6. venules

Front 20

What are the three layers that make up the structure of arteries and veins?

Back 20

1. Tunica intima

2. tunica media

3. tunica adventitia

Front 21

Describe the tunica intima

Back 21

endothelium

basement membrane

lamina propia (thin conn. tissue)

fenestrated elastic fibers (internal elastic membrane)

Front 22

Describe the tunica media

Back 22

smooth muscle cells arranged circularly around vessel
(controls blood flow with vasodilation or vasoconstriction)

elastic / collagen fibers

external elastic membrane

Front 23

Describe the tunica advertitia

Back 23

connective tissue that varies from dense to loose and is continuous with connective tissue around the vessels

Front 24

describe large elastic arteries
what do they do best and what's the tunica media like?

Back 24

have large diameters so they are good conducting arteries

have thin walls

they accomodate high pressure

tunic media is more elastic with less smooth muscle

Front 25

Describe muscular arteries and what they do best and what the tunica media is like?

Back 25

have small diameter

thick walls

tunica media is a little elastic but has lots of smooth muscle

Front 26

What are arterioles like and what is their tunica media like?

Back 26

smallest

tunica media has smooth muscle and just a few elastic fibers

Front 27

Where are valves in the vessels?

Back 27

in large diameter veins
(medium veins and lower extremities)

Front 28

Vaso Vasorum

Back 28

small blood vessels supplying nutrition to blood vessel tunica advertitia and tunica media

Front 29

What are arteriovenous anastomoses?

Back 29

they allow the blood to flow directly from arterioles to small veins (no capillaries)

Front 30

What are portal veins?

Back 30

They start in primary capillary network, extend and end in a secondary capillary network

hepatic portal

hypothalamohypophysial portal

Front 31

What does the hepatic portal veins do?

Back 31

carries blood from the capillaries in the gastrointestinal tract / spleen to sinusoids in the liver

Front 32

Discuss innervation of blood vessels

Back 32

unmyelinated sympathetic nerves

have plexuses in the tunica advertitia

have neurotransmitters in tunica media

Front 33

Sympathetic nerve stimulation in blood vessels causes_____________?

Parasympathetic nerve stimulation in blood vessels causes________?

Back 33

vasoconstriction

vasodilation

Front 34

Arteriosclerosis

Back 34

hardening of the arteries with age

arteries (especially the large ones) become less elastic and the resistance increases.

heart has to work harder as there is hypertrophy of the tunica intima and media

Front 35

Atherosclerosis

Back 35

deposition of material in the walls of arteries to form distinct plaques

Front 36

Describe the pathway of pulmonary circulation starting at right ventricle

Back 36

right ventricle>>

pulmonary trunk>>j

right and left pulmonary arteries>>

left atrium

Front 37

What are the 3 main parts to the aorta?

Back 37

1. ascending aorta

2. aortic arch

3. descending aorta

Front 38

what branches off the ascending aorta?

Back 38

right and left coronary arteries

Front 39

what branches off the aortic arch?

Back 39

brachiocephalic artery

left common carotid

left subclavian

Front 40

What branches off the descending aorta?

Back 40

thoracic aorta

abdominal aorta

2 common illiac aortas

Front 41

What are the main arteries for the head and neck?

Back 41

Right side:

brachiocephalic>>common carotid>>subclavian

common carotid>>internal and external carotid

subclavian>>vertebral>>basilar

Front 42

What arteris supplies the brain with blood and helps form the circle of willis?

Back 42

internal carotid and vertebral

Front 43

describe the arteries from the heart to the fingers

Back 43

aorta>>aortic arch>>brachiocephalic>>subclavian>>axillary>>brachial>>ulnar and radial>>superficial and deep palmar arch>>digits have medial and lateral arteries

Front 44

What does the thoracic aorta supply blood flow for?

Back 44

visceral --thoracic organs, bronchi / bronchioles in lungs, pericardium, esophogus

parietal--thoracic wall, diaphragm

Front 45

What are the branches from the thoracic aorta?

Back 45

anterior and posterior intercostal arteries

superior phrenic artery

Front 46

What does the abdominal aorta supply blood to ?

Back 46

visceral--kidneys, adrenals, gonads
celiac, (superior mesenteric, inferior mesenteric)

parietal--diaphragm and ab wall

Front 47

Describe the arteries of the pelvis

Back 47

abdominal aorta divides into:
R & L common iliac
>>external (lower limbs)
>>internal (pelvic area
visceral: bladder, vag, rectum uterus
parietal: pelvis walls/floor, lumbar, gluteal, proximal thigh muscles, external genitalia

Front 48

Describe the arteries of the lower limb

Back 48

external common iliac>>
femoral>>
popliteal>>anterior tibial / dorsalis pedis / digital branches
>>posterior tibial / fibular (peroneal) / medial /lateral plantar / digital branches

Front 49

What are the 3 major veins returning blood to the heart?

Back 49

Superior vena cava

Inferior vena cava

Coronary sinus

Front 50

What are the 3 major types of veins?

Back 50

1. Superficial (larger, generally in limbs)

2. Deep (larger, generally in head and trunk)

3. Sinuses (cranial cavity and heart)

Front 51

What are the veins of the head and neck?

Back 51

external jugular (posterior head and neck)

internal jugular (cranial cavity, anterior face and neck)

internal jugular is a continuation of cranial sinuses that proceeds to subclavian>>brachiocephalic...

Front 52

what are the veins of theupper limb?

Back 52

cephalic>>median cubital (elbow)

basilic

brachial>>radial /ulnar

they all go through axillary vein and subclavian

Front 53

What are the veins of the thorax?

Back 53

R & L brachiocephalic
>>internal thoracic
>>anterior intercostal

azygos (unpaired) vein
>>posterior intercostal (right side)
>>hemiazygos (left side

Front 54

What are the veins of the abdomen and pelvis?

Back 54

posterior ab wall >> ascending lumbar>> either hemiazygos (left side) or azygos (right side)

rest of ab wall, pelvis, lower limbs, gonads, kidneys and adrenal glands >>inferior vena cava

pelvis >> internal iliac veins >> external iliac veins >> common iliac veins >> inferior vena cava

Front 55

What is the hepatic portal system?

Back 55

carries blood through veins from abdominal viscera (stomach, intestines, spleen) to liver sinusoids

delivers nutrients from intestines to liver

Front 56

What veins unite to make hepatic portal system?

Back 56

superior / inferior mesenteric

splenic

pancreatic

gastric

Front 57

What is the longest vein in the body?

Back 57

Great saphenous vein (in leg)

Front 58

Describe the veins of the lower limb

Back 58

superficial:

great saphenous and small saphenous
>>popliteal

Deep:
distal (paired with arteries
proximal (unpaired)
anterior / posterior tibial >> popliteal >> femoral >> external iliac

anterior / posterior tibial also >> fibular (peroneal)

Front 59

What is laminar flow?

Back 59

flows in a streamlined fashion

outer layer moves slower
inner layer moves more quickly

Front 60

What is turbulent flow?

Back 60

when the rate of flow exceeds a critical velocity, passes a constriction, a sharp turn or a rough surface.

occurs mostly in heart of where the arteries are branching

Front 61

Describe the process of taking blood pressure in a clinical setting

Back 61

1. place cuff on arm and inflate

2. place stethoscope just above elbow on the inside part

3. gradually lower the pressure until you hear the first sounds of turbulent blood flow = systolic value

4. Continue lowering the pressure until laminar flow has been reached and there is no sound and you have = diastolic value.

Front 62

What is the kortkoff sound?

Back 62

systolic pressure
sound of first turbulent blood flow while taking blood pressure

Front 63

What is Poiseville's Law?

Back 63

states that a small change in radius of a vessel makes a very BIG change in flow

explains how small changes in vaso dilation and constriction make a big impact on blood pressure.

Front 64

What is the value of the viscosity of blood compared to H20 if H2O is a 1?

What largely influences the viscosity of blood?

Back 64

3.0-4.5

hematocrit (% of total blood volume composed of RBC's)
dehydration and excess production of erythrocytes

Front 65

What is the critical closing pressure?

Back 65

the pressure below which a vessel collapses. Blood flow stops

Front 66

What is Laplace's Law state?

Back 66

As the diameter increases it also increases the force on a vessel, even in the pressure remains the same

i.e. if you have a bulge the vessels diameter is going to grow therefore more force is applied to vessels wall. And then it's thinner. Recipe for aneurysms!

Front 67

What is vascular compliance?

Are arteries or veins more compliant?

Back 67

Tendency for blood vessels volume to increase as pressure increases

stretchy = more compliant

stiffer = less compliant

VEINS are more compliant

Front 68

In the systemic circulation at any given time where is the blood distributed?

Back 68

veins 64%

arteries 16%

capillaries 5%

Front 69

What is the pulse pressure and what two factors influence this?

Back 69

systolic (@120) minus diastolic (@ 80)

1. SV

2. Vascular compliance

Front 70

Describe capillary exchange

Back 70

movement of substances into and out of capillaries

fluids move from areas of higher concentration to areas of lower concentration

fluid that remains in interstitial space eventually enters the lymphatic system

Front 71

What is NFP?

Back 71

Net Filtration Pressure

force responsible for moving fluid across capillary walls

Front 72

What is the formula for NFP?

Back 72

Net Hydrostatic Pressure - Net Osmotic pressure

Front 73

What is Net Hydrostatic Pressure?

Back 73

BP - Pressure in interstitial fluid

Front 74

What is Net Osmotic Pressure?

Back 74

Blood Colloid Osmotic Pressure (BCOP)
minus
Interstitial Colloid Osmotic Pressure (ICOP)

BCOP - ICOP

Front 75

Describe fluid exchange across the capillary walls

Back 75

1. artery
fluid moves out of capillary because of a positive net filtration pressure

2. 9/10 of fluid goes back into venous end and 1/10 remains in interstitial fluid

3. fluid goes into venous end because the net filtration pressure is negative

Front 76

What is the result of an imbalance in the amount of interstitial fluid?

Back 76

swelling / edema

Front 77

Where are the 10 major points where a pulse can be monitored?

Back 77

1. Facial artery

2. Superficial temporal artery

3. Common Carotid artery

4. axillary artery

5. Brachial artery

6. Radial artery

7. Femoral Artery

8. Popliteal artery

9. Dorsal Pedis artery

10. Posterior tibial artery

Front 78

What is venous tone?

Back 78

continual state of partial contraction of the veins by sympathetic stimulation

constriction of the veins causes larger venous return to heart which causes a bigger prelod which produces a bigger CO

vice versa

Front 79

What effect does gravity have on vessels?

Back 79

Pressure at aorta is 100 mm Hg and at right atrium is 0 mm Hg.

Everything else is at the mercy of gravity.

Standing for long periods of time causes edema because more fluid remains in the interstitial space

Front 80

What are the two ways blood is controlled in the tissues?

Back 80

Local Control

Nervous / Hormonal Control

Front 81

What substances do local control mechanisms respond to when detected in the blood?

Back 81

When increased levels of metabolic substances (CO2, lactic acid, adenosine, adenosine monoposphate /diphosphate, EDRF, K+ and H+) are detected, local tissues release vasodialators

Front 82

What is vasomotion?

Back 82

cyclical and periodic contractions as local tissues respond to tissue blood needs

Front 83

Describe how Nervous / Hormonal Regulation of tissue blood works

Back 83

1-30 secs and is sympathetic stimulation

constant waves of ap's are being sent to the vasomotor center from the vessels and creates a vasomotor tone

Also, the pons, midbrain and diencephalon all send msgs to the vasomotor center

release of epi or norepi in response to these messages causes vasoconstriction

Front 84

Describe how baroreceptors regulate MAP.

Is it short term or long term?

Back 84

ap's from the aortic arch reflex go to vagus nerve (X) and ap's from the carotid sinus reflex go to the glossopharangeal nerve (IX) where they end up in the cardio regulatory and vasomotor centers respectively

centers respond accordingly with para or sympathetic stimulation

Short term, adaptable

Front 85

Explain how the adrenal medullary mechanism regulates MAP

Is it short term or long term?

Back 85

sympathetic nerve fibers stimulate the adrenal medulla (like during exercise)
to release epi and norepi

Its like a boost to the sympathetic stimulation

Very short term

Front 86

Explain how the Chemoreceptor Reflex regulates MAP

Is it short term or long term?

Back 86

carotid bodies >> glosso

aortic bodies >> vagus

lack of O2 (like in altitude) increases ap's to vasomotor center and Vasomotor tone increases

Short term
Chemoreceptors also react to increased levels of CO2 and H+

It's like an emergency detector to protect the heart and brain

Front 87

Explain how the CNS Ischemic Response regulates MAP

Is it short term or long term?

Back 87

responds to low blood flow to medulla oblongota.

Super emergency vasoconstriction

Short term

Front 88

Explain how the Renin-Angiotensin-Aldosterone mechanism regulates MAP

Is it short term or long term?

Back 88

affects kidney function

When the blood volume / arterial pressure is high, urine output increases

the kidney's release renin which makes angiotensi I and angiotensin II

Angiotensin II causes:
--vasoconstriction in arterioles and veins to increase BP

--adrenal cortex to release aldosterone

--makes you thirsty, crave salt and release ADH

Long term

Front 89

What effect does aldosterone have on the kidneys?

Back 89

Makes them take in more Na+ and Cl- ions and water and therefore decreases urine output (saves the water for more blood volume)

Front 90

Explain how the ADH (vasopresin) mechanism regulates MAP

Is it short term or long term?

Back 90

sort of like partners with the renin-angiotensin-aldosterone mechanism.

baroreceptors detect decreased BP and causes vasopresin ADH to be secreted from posterior pituitary

causes vasoconstriction
decreases urine output

this mechanism is sensitive to ion concentration in the plasma

Long term

Front 91

Explain how the atrial natriuretic mechanism regulates MAP

Is it short term or long term?

Back 91

atrial natriuretic is a polypeptide hormone released by cells in the atria of the heart.

It is released when there is a large increase in the volume of venous return

effects levels of urine output in kidneys

Long term

Front 92

Explain how the fluid shift mechanism regulates MAP

Is it short term or long term?

Back 92

plays a role in dehydration.

when BP goes up fluid goes out of the capillaries into interstitial space

when BP drops fluid goes into the capillaries from the interstitial spacej

Long term

Front 93

Explain how the stress relaxation response regulates MAP

Is it short term or long term?

Back 93

more contraction by smooth muscle cells in response to decreased BP

more relaxation when BP is increased (like in a transfusion)

Long term