12/8/2014 Medical Physiology Vascular Control II Amit S. Dhamoon Flashcards Preview

Unit 5 > 12/8/2014 Medical Physiology Vascular Control II Amit S. Dhamoon > Flashcards

Flashcards in 12/8/2014 Medical Physiology Vascular Control II Amit S. Dhamoon Deck (24)
Loading flashcards...
1
Q

At low preload, SV and CO are?

A

Low

2
Q

At high preload, SV and CO are?

A

High

3
Q

As cardiac function goes up, is CO or venous return, central venous pressure does what?

A

Goes up and then levels off (see notes page 340).

4
Q

Give an example of a pathologic negative inotropic effect, where the CO vs CVP graph shifts downward from normal?

A

Heart attack, see page 341 in notes.

5
Q

Tachycardia is an example of the body trying to increase CO when it has a decreased ______.

A

preload.

6
Q

What is the effect of venous vasoconstriction?

A

The blood normally pooling is mobilized –> venous return increases –> SV increases

7
Q

Preload is the same as:

A

left ventricular end diastolic volume

8
Q

What is the effect of digitalis?

A

Increase contractility

9
Q

At steady state, CO = what quantity?

A

Venous return

10
Q

What three elements of cardiac and vascular function are interdependent?

A

Cardiac Output
Right Atrial Pressure (same as Central Venous Pressure)
Venous Return
Changes in these quantities are quickly resolved.

11
Q

A transient increase in the right atrial pressure would lead to?

A

Increase in CO
Decrease in VR
However, since CO > VR, RAP would fall until they were equal again.

12
Q

If VR > CO, what will change to rebalance them?

A

RAP will increase so CO = VR

13
Q

The cardiovascular system only operates stable when:

A

CO = VR

14
Q

What is the one parameter that can change both the Starling curve and the VR curve?

A

TPR (affecting the arterioles)

15
Q

Pulse pressure is determined by:

A

SV

16
Q

Pulse pressure is proportional to:

A

SV/C

17
Q

Digitalis is what kind of drug?

A

Cardiac glycoside

18
Q

What things could elevate the cardiac function curve?

A

Increase in HR
Increase in SV (increase in CO)
Digitalis

19
Q

Give an example of how sympathetic stimulation could be inhibited.

A

Anesthesia

20
Q

Give an example of where CO and VR can both increase substantially, but leave RAP (CVP) unchanged.

A

Exercise. Heart is beating faster, but no change in pressure in right atrium (see page 347 in notes).

21
Q

During exercise, sympathetic ____ increases the mean systemic filling pressure because the blood volume is now contained in a smaller cardiovascular system.

A

venoconstriction

22
Q

Why does venoconstriction increase mean systemic filling pressure, but not arteriolar constriction?

A

Because the veins can hold a much larger amount of blood.

23
Q

Spinal anesthesia results in:

A

inhibited sympathetic drive –> venodilation, lower CVP, lower VR, lower CO.

24
Q

What does spinal anesthesia do to the mean systemic filling pressure?

A

Lowers it (venodilation)

Decks in Unit 5 Class (36):