Circulation and Hemodynamics

Question 1

Rank the following vessels from highest pressure to lowest: Arteries, Veins, Arterioles

Answer 1

1) Arteries
2) Arterioles
3) Veins

Question 2

What feature of arterioles can control blood flow by changing resistance?

Answer 2

Contraction of smooth muscle walls

Question 3

What is a large cross-sectional area of vessels with a single endothelial lining?
What goes on at this location?

Answer 3

1) Capillaries

2) Nutrient, waste, and gas exchange

Question 4

Veins can contract to move blood to?

Why?

Answer 4

Arterial side in order to increase BP

Question 5

What is the equation for blood flow?

Answer 5

Q (flow) = ΔP (pressure gradient) / R (resistance)

Question 6

What is the important variable in poiseuille’s law?

Answer 6

Vessel radius (r)

R= (8ηl) / (πr^4)

Question 7

Adding resistance beds in series?

Answer 7

Increases resistance

Question 8

Adding resistance beds in parallel?

Answer 8

Decreases total resistance

Question 9

What is the equation for reynolds number?

Answer 9

=pdv/η

density, diameter, velocity, viscosity

Question 10

What would reynolds number be to transition from laminar to turbulent flow?

Answer 10

Greater than 2000

Question 11

Turbulent blood flow can lead to?

Answer 11

Bruits and arteriosclerosis

Question 12

What does compliance of blood vessels describe?

Answer 12

How much the vessel expands due to change in lumen hydrostatic pressure

Question 13

What has more compliance, veins or arteries?

Answer 13

Vein

Question 14

What happens to compliance of arteries as we age?

Answer 14

Decrease

Question 15

Smooth muscle contraction causes a shift in compliance by?

Answer 15

Moving blood to arterial side and increasing pressure

Question 16

The pulsatile nature at aortic end due to compliance and distention during ejection and recoil during diastole is lost by?

Answer 16

Arterioles

Question 17

What is the greatest pressure reached in large arteries?

What is the lowest?

Answer 17

1) Systolic pressure

2) Diastolic pressure

Question 18

What does the pulse pressure equal numerically?

Answer 18

Systolic - diastolic = 40

Question 19

What does the mean pressure equal numerically?

Answer 19

diastolic pressure + 1/3 pulse pressure = 80 + (40/3) = 93.3

Question 20

When there is a decrease in arterial compliance such as from arteriosclerosis, what happens to:
Pulse pressure?
Systolic pressure?
Mean arterial pressure
Diastolic pressure?

Answer 20

1) Increases
2) Increases
3) Increases
4) Stay same or decrease

Question 21

What are the features of pressure, compliance, and volume in veins?

Answer 21

Low pressure, high compliance, large volume

Question 22

What vessel type is primarily responsible for controlling distribution of blood?

Answer 22

Arterioles

Question 23

Where is laminar flow in a vessel?

Answer 23

Center

Question 24

What would the blood viscosity be in an anemic patient?

Answer 24

Low

Question 25

What is the flow rate of blood in the GI system if the arterial pressure is 50 at the beginning the venous pressure is 5 at the end, and the resistance throughout the GI system is 4.5?

Answer 25

10 (50-5)/4.5 Q = ΔP / R

Question 26

Small changes in radius can cause large changes in?

Answer 26

Resistance

Question 27

What does hydrostatic pressure do to fluid? | Osmotic pressure?

Answer 27

1) Pushes out | 2) Pulls in

Question 28

Capillary hydrostatic pressure is what type of force? | What does it do?

Answer 28

1) Positive | 2) Pushes fluid out of capillary

Question 29

Interstitial hydrostatic pressure is what type of force? | What does it do?

Answer 29

1) Negative | 2) Pushes fluid into capillary

Question 30

Capillary osmotic pressure is what type of force? | What does it do?

Answer 30

1) Negative | 2) Pulls fluid into capillary

Question 31

Interstitial osmotic pressure is what type of force? | What does it do?

Answer 31

1) Positive | 2) Pulls fluid into interstitium

Question 32

What startling force is affected in heart failure and DVT? | What does this lead to?

Answer 32

1) Increase of hydrostatic capillary pressure | 2) Movement out of capillary

Question 33

What startling force is affected in malnutrition? | What does this lead to?

Answer 33

1) Decrease of capillary osmotic pressure | 2) Movement out of capillary

Question 34

What startling force is affected in lymphatic obstruction? | What does this lead to?

Answer 34

1) Increase of hydrostatic interstitial pressure | 2) Movement into capillary

Question 35

When does active hyperemia occur?

Answer 35

During exercise when tissue needs more blood flow

Question 36

When does reactive hyperemia occur?

Answer 36

Increase in blood flow in response to a period of ischemia

Question 37

The blood flow to the brain, heart, and active skeletal muscle are controlled by?

Answer 37

Metabolic control

Question 38

The blood flow to the GI and skin are controlled by?

Answer 38

Sympathetic tone (central control)

Question 39

The blood flow to the lungs is controlled by?

Answer 39

Hypoxic vasoconstriction

Question 40

The blood flow to resting skeletal muscle is controlled by?

Answer 40

Central control

Question 41

What is the distribution of blood from the aorta to the various areas: 1) Cerebral 2) Coronary 3) Renal 4) GI 5) Skeletal muscle 6) Skin

Answer 41

1) 15% 2) 5% 3) 25% 4) 25% 5) 25% 6) 5%

Question 42

What effect does aortic stenosis have on BP?

Answer 42

Decreases