Lecture 10 Arterial and Venous Systems and Lymphatics Flashcards Preview

Human Physiology 1 -- Zach H. > Lecture 10 Arterial and Venous Systems and Lymphatics > Flashcards

Flashcards in Lecture 10 Arterial and Venous Systems and Lymphatics Deck (71)
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1

What are some of the factors that increase lymph flow, and also interstitial fluid pressure?

Elevated capillary hydrostatic pressure

Decreased plasma colloid osmotic pressure

Increased interstitial fluid colloid osmotic pressure

Increased permeability of capillaries

2

How do you calculate the rate of lymph flow?

Rate of Lymph Flow =
interstitial fluid pressure x activity of lymphatic pump

3

True or False:

Lymph vessels posses 1-way valves similar to veins.

True

4

At what condition does lymph flow reach its maximum?

When interstitial pressure rises slightly above atmospheric pressure.

5

The least amount of damping of the pressure pulses would occur in which of the following components of the circulatory system?

a) femoral artery
b) arterioles
c) capillaries
d) venules

a) femoral artery

6

Which of the following factors affect pulse pressure?

a) vascular elastance
b) arterial compliance
c) stroke volume
d) all the above
e) B and C only

e) B and C only

7

Which of the following is the most important means for the exchange of substances between the blood and the interstitial fluid?

a) blood hydrostatic pressure
b) capillary oncotic pressure
c) diffusion
d) interstitial fluid hydrostatic pressure
e) osmosis

c) diffusion

8

What is the definition of vascular distensibility?

Vascular distensibility -> (increase in volume) /(increase in pressure) X (original volume)

9

What affect does increasing the pressure in a vessel have on the vascular distensibility?

Increasing pressure would decrease vascular distensibility.

10

Does vascular distensibility increase or decrease when volume increases?

The vascular distensibility will increase.

11

True or False:

Pulmonary artery distensibility are about 6 times that of systemic arteries.

True

12

Fill in the Blank:

Pulmonary vein distensibilities are about the _________ as for systemic veins.

same

**Thus, pulmonary and systemic veins have about the same distensibility.

13

How much more distensible are veins than arteries?

8 times more distensible

14

What does capacitance describe?

Capacitance describes the distensibility of blood vessels.

15

The formula for vascular compliance = increase in volume / increase in pressure. What does vascular compliance tell us?

That the total quantity of blood (ml) that can be stored in a given portion of the circulation for each mmHg rise in pressure.

16

Fill in the Blank:

Capacitance (ml/mmHg) is __________ proportional to elastance.

Inversely

17

What is compliance equal to?

compliance is equal to distensibility X volume

18

True or False:

Capacitance is inversely proportional to volume and directly proportional to pressure.

FALSE - capacitance is directly proportional to volume and inversely proportional to pressure.

19

Fill in the Blank:

_________describes how volume changes in response to a change in pressure.

Capacitance

20

Is capacitance much greater for veins or arteries?

Capacitance is much greater in veins.

21

True or False:

Capacitance of arteries decreases with age.

TRUE

22

What is the relationship between elastic tissue, elastance, and compliance?

The greater the amount of elastic tissue in a blood vessel, the higher the elastance and the lower the compliance.

23

What does compliance measure?

Compliance is a measure of the ease with which a hollow viscus may be distended.

*example: volume change resulting from the application of a unit pressure differential between the inside and outside of the viscus; the reciprocal of elastance.

24

What does vascular compliance tell you?

Total quantity of blood that can be stored in a given portion of the circulatory system.

25

What is elastance a measure of?

The tendency of a hollow viscus to recoil toward its original dimensions upon removal of a distending or collapsing force.

26

A systemic vein is about eight times as distensible as its corresponding artery and has a volume about three times as great. How would the systemic vein's compliance compare to that of a corresponding artery?

Compliance = (8) x (3) = 24

27

Study figure 15-1 from the book.

Guyton and Hall

28

How do you calculate pulse pressure?

pulse pressure = stroke volume / arterial compliance

29

Given that pulse pressure = stroke volume / arterial compliance, comment on the factors that would negatively affect pulse pressure? Thus, what would increase pulse pressure and what is the most important determinant of pulse pressure?

Stroke Volume Output of the Heart:
-most important determinant of pulse pressure
-diastolic pressure remains unchanged during ventricular systole
-pulse pressure increases to the same extent as the systolic pressure

Compliance of the Arterial Tree:
-Decreases in compliance (capacitance)
>e.g., aging, result in an increase in pulse pressure

30

What are 2 of the 4 conditions that cause abnormal contours of the pressure pulse wave?

Aortic Valve Stenosis
-diameter of aortic valve opening is reduced
-aortic pressure pulse is decreased significantly

Atherosclerosis

Patent Ductus Arteriosus
-half or more of cardiac output flows back into pulmonary artery and lung blood vessels
-diastolic pressure falls very low before next heartbeat
>because blood is being shunted away from the aorta

Aortic Regurgitation
-aortic valve is absent or will not close completely
-aortic pressure may fall to 0 between heartbeats