2.10 - Vessels Of The Systemic Vasculature

Question 1

What are the determinants of aortic pressures?

Answer 1

systolic and diastolic pressure, compliance and ventricular contractility

Question 2

What are the five pulse qualitites?

Answer 2

Frequency, rhythm, amplitude, steepness and tension

Question 3

What is the Mean Arterial Pressure?

Answer 3

MAP is the mean between systolic and diastolic pressure and is the mean driving force for blood flow.

Question 4

Is the formula for MAP different for certain arteries? If yes, why?

Answer 4

The formula for MAP is different in the aorta than for peripheral arteries as the pulse wave shape is different

Question 5

Describe pulse wave velocity

Answer 5

It is the distance traveled by the pulse wave divided by the time for the wave to travel that distance and represents the impulse travelling along a vessel. It is dependent on vessel compliance.

Question 6

How does vessel compliance effect vessel compliance?

Answer 6

A stiffer vessel or more muscular artery results in a faster PWV

Question 7

Describe the changes in the pulse wave as it moves towards the periphery

Answer 7

Increased systolic pressure, decreased MAP and delayed velocity.

The dicrotic notch is lost but a second hump appears

Question 8

Describe the mechanism for the increase in systolic pressure in the pulse wave in distal arteries and what does it result in?

Answer 8

The reflection of the pulse wave as resistive elements (arterioles) adds to local pressure. This results in the 1st hump being sharpened and the appearance of the second hump

Question 9

Compare the pulse wave velocity in the aorta, radial artery and a small artery

Answer 9

Aorta: 4-6m/s < Radial artery: 8-12m/s < Small artery: 15-35m/s

Question 10

Compare the compliance of the venous sytem to the arterial side

Answer 10

Compliance greatly increased. Large volume changes possible with small changes in pressure

Question 11

What effect does aging have on pressure on blood vessels

Answer 11

Pressure changes in aging are due to compliance changes in the aorta

Question 12

The largest amount of arterial pressure generated during systole is dissipated at which of the following locations in the vascular bed?

A: Aortic arch

B: Aorta-large arterial juncture

C: Arterial-arteriolar juncture

D: Arteriolar-capillary juncture

E: Capillary-venular juncture

Answer 12

D: Arteriolar-capillary juncture

Question 13

In which part of the vascular bed is the pulse velocity largest?

A. Aorta

B: Large arteries

C: Arterioles

D: Precapillary beds

E: Capillary

Answer 13

D: Precapillary beds