Vascular Control I Flashcards Preview

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Flashcards in Vascular Control I Deck (27):
0

The heart is a _____________ that acts upon an _____________ in order to produce an __________________.

Dynamic system

Input

Output

1

Input=

Venous return

2

Output=

Cardiac output

3

If there are changes in a hearts input, are changes in output required?

Yes, the body does everything it can to keep these equal to one another

4

What is preload?

End diastolic volume

5

What is afterload?

End systolic pressure

6

What happens when preload increases?

Stroke volume and cardiac output also increase

7

Is preload or after load a reflection of volume status?

Preload

8

Where does the majority of the volume reside in the circulatory system?

In the peripheral venous compartment

9

Which vascular compartment is associated with preload?

Central venous compartment

10

What vascular compartment is associated with after load?

Arterioles

11

Blood leaves the central ventouse compartment (right atrium) by entering the right ventricle at a rate that is equal to.....

Cardiac output

12

What is the definition of venous return?

The rate at which blood returns to the thorax from the peripheral vascular beds (the rate it enters the central venous compartment)

13

What anatomical structures comprise the central venous compartment?

Great veins in thorax and right atrium

14

Which pressure is larger, peripheral venous pressure, or central venous pressure?

Peripheral venous pressure

15

What happens when peripheral venous pressure is EQUAL to central venous pressure?

There is no flow

16

When blood volume or venous return increases, what happens to the venous function curve?

It shifts to the right

17

What happens to the RAP at any constant CVP with an increase in pump flow?

It decreases

18

at increase pump rates, the amount of blood in the arterial system _______________ while the amount of blood in the venous system _______________. What is the effect on the pressure for each?

Increases

Decreases

The arterial pressure increases and the venous pressure decreases

19

What is MSFP?

Mean systemic filling pressure. It is the bold pressure at zero flow.

20

Does MSFP increase or decrease with greater blood volume?

It increases

21

At any given RAP, an increase in CVP with increased blood volume drives greater venous return. What is the effect on the vascular function curve?

A shift upwards

22

Do vasoconstriction and vasodilation effect MSFP?

No, because blood volume has not changed (you are just shifting where it is)

23

When arterioles vasodilate, what is the effect on stroke volumes and cardiac output?

Stroke volume increases, cardiac output increases

24

A transient increase in RAP, there would be an _____________ in CO and a _____________ in VR (venous return).

Increase

Decrease

25

What are the effects of a transfusion on MAP and CO?

There is an increase in both

26

What is the way to produce a different steady state match between venous return and CO?

Change BOTH the cardiac function curve and the vascular function curve