Part 1: The Systemic Circulation Flashcards

1
Q

What happens to pulse pressure as you move further from the heart?

A

It widens (increases - larger difference between systolic and diastolic in vessels further from the body)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Do capillaries and veins have a pulse pressure?

A

No

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Where is the greatest decrease in arterial pressure?

A

across the arterioles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What plays a larger role in sculpting the mean arterial pressure?

A

diastolic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What happens to the mean arterial pressure as you move throughout the circulatory system?

A

it decreases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Which pressure increases further from the heart, systolic or diastolic?

A

Systolic

DIastolic DEcreases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the three components of the vascular wall (both artery and vein)?

A

1) Tunica Intima
2) Tunica Media
3) Tunica Adventitia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What cells line blood vessels and lymphatics?

A

endothelial cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How does arterial tunica intima differ from venous tunica intima?

A

It has an internal elastic lamina (IEL)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the tunica intima?

A

subendothelial connective tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How does venous tunica media differ from arterial?

A

It has fewer smooth muscle cells and NO external elastic lamina

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the tunica adventitia?

A

mostly connective tissue with some smooth muscle cells and vasa vasorum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What do arteries have that veins do not?

A

1) elastic lamina
2) more smooth muscle
3) less connective tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What layer of the vascular wall is more pronounced in veins?

A

tunica adventitia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Rank these in order of increasing compliance:

elastic lamina, smooth muscle, collagen

A

collagen < smooth muscle < elastic lamina (highest compliance)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Name the 3 types of capillaries

A

1) Continuous (tight junctions between cells; no holes)
2) Fenestrated (holes)
3) Discontinuous (sinusoidal) (endothelial cells are separated by wide spaces)

17
Q

Where are continuous capillaries found?

A

muscle, connective tissue

18
Q

Where are fenestrated capillaries found?

A

kidney, intestine

19
Q

Where are discontinuous capillaries found?

A

liver, bone marrow, spleen

20
Q

According to the LaPlace relationship, what ratio should be high to achieve the greatest control of vessel diameter and blood flow?

A

Wall thickness/lumen diameter

thick walls with thin diameter aka arteries

21
Q

What has the highest wall thickness/lumen diameter ratio?

A

pre-capillary sphincters

22
Q

Why do veins regulate volume more than flow or pressure?

A

because they have relatively small wall thickness/lumen diameter ratio

23
Q

Do lower or higher compliant aortas generate larger pulse pressures (greater difference between systolic and diastolic?)

A

lower compliant aortas do!

Why? stiffer walls create a higher afterload generating a larger systolic pressure. Diastolic pressure decreases creating larger pulse pressure

24
Q

How do highly compliant vessels generate pressure?

A

recoil (stiffer, low compliant vessels have less recoil)

25
Q

What is an increase in pulse pressure bad?

A

it changes afterload in the heart (usually causing more oxygen utilization)

26
Q

What is more dangerous, low or high compliant aorta?

A

low! creates larger afterload causing the heart to consume more O2

27
Q

What happens to compliance of a blood vessel as blood volume increases?

A

it decreases because load on the vascular wall is first borne by elastin and smooth muscle (high compliance) at lower volumes and lastly by collagen (low compliance) at huger volumes.

28
Q

What clinical danger do you need to look out for with blood volume expansion?

A

hypertension

29
Q

What is the importance of an highly compliant aorta?

A

the recoil that occurs after the aortic valve closes acts as a sort of second pump after systole that maintains constant flow during diastole.

NEED TO HAVE HIGH COMPLIANCE

30
Q

What happens to aortic compliance as we age?

A

it decreases (less elastin (highly compliant) and more collagen (low compliance)

31
Q

What does a decrease in compliance of the aorta result in?

A

more cardiac work and a larger pulse pressure

afterload likely went up too causing an increase in O2 consumption

32
Q

Younger people get _________ (systolic or diastolic) hypertension

A

diastolic (D is earlier than S in the alphabet)

33
Q

Older people get __________ (systolic or diastolic) hypertension

A

systolic because aortic compliance has likely decreased

34
Q

What can an increased pulse pressure lead to?

A

1) congestive heart failure

2) can contribute to systolic hypertension, cardiac hypertrophy, aortic distention, low exercise tolerance

35
Q

Because arteries maintain relatively low compliance, they are known as __________ vessels

A

resistance

36
Q

Conversely, because veins feature high compliance, they are known as __________ vessels

A

capacitance (meaning they can hold a lot of blood)

37
Q

What happens to the compliance of veins as arterial pressure dramatically increases?

A

venous compliance decreases

why saphenous vein can be used for coronary artery grafts even though they are morphologically different

38
Q

Where is the pressure pulse going to be the highest?

A

furthest from the heart (ex: femoral)

39
Q

As compliance decreases, what happens to the pressure pulse?

A

It INCREASES because it is easier for the energy wave to run quickly down a stiff tube