CV&R

Question 1

What is true of Korotkoff sounds?

Answer 1

1. Cuff pressure approximates systolic pressure when Korotkoff sound are first heard.
2. Cuff pressure approximates diastolic pressure when Korotkoff sounds become muffled and disappear.
3. Korotkoff sounds are only present when the artery is partially occluded.

Question 2

How can volume flow rate be calculated?

Answer 2

Q = change in pressure / resistance

Question 3

How does the velocity of blood flow relate to the total cross-sectional area of a group of blood vessels?

Answer 3

As total cross sectional area increases, velocity decreases

Question 4

What is the main determinant of total peripheral resistance?

Answer 4

Vessel diameter

Question 5

What is true in regards to auto regulation?

Answer 5

1. Results in local changes in the rate of blood flow
2. Involves the vasodilation factor, nitric oxide
3. Stimulated by hypoxia
4. Occurs without neural or hormonal input

Question 6

What properties of a vessel make it easy to stretch?

Answer 6

Small elastance and large compliance

Question 7

What is the most important force in venous flow?

Answer 7

The pressure gradient generated by the heart

Question 8

What does Starling’s law state?

Answer 8

That within physiological limits the strength of ventricular contraction will adjust to match venous return

Question 9

How does venoconstriction affect cardiac output?

Answer 9

Helps to push blood back to heart so increases venous return, stroke volume and cardiac output.