Introduction to Haemodynamics

Question 1

What is Hydraulic resistance inversely proportional to?

Answer 1

1/r^4

Question 2

What vessel has the greatest cross sectional area

Answer 2

capillaries

Question 3

Where does pressure stay high all the time

Answer 3

The large arteries

Question 4

What is the effect of arterial distensibility?

Answer 4

It reduces cardiac O2 consumption

Question 5

What are WindKessels?

Answer 5

Any feature that can dampen out oscillations in pressure

Question 6

Describe laminar flow.

Answer 6

Fluid flows in layers, silent flow, flow is proportional to pressure difference

Question 7

Describe Turbulent flow.

Answer 7

non-uniform vessel surface, generates audible vibrations, flow is proportional to square root of pressure difference

Question 8

Whar is Reynolds number equal to?

Answer 8

(v.D.p)/n
re greater than 2000 = turbulance

Question 9

What is compliance?

Answer 9

The measure of rigidity of a vessel

Question 10

What is the equation for compliance?

Answer 10

C = change in volume/change in pressure (ml/mmHg)

Question 11

Does Ca contribute to MAP determination or PP

Answer 11

PP - change in pressure associated with each cardiac ejection

Question 12

What is pulse pressure increased by?

Answer 12

Decreased Ca and increased stroke volume

Question 13

What is pulse pressure decreased by?

Answer 13

Reduced stroke volume