2. Haemodynamics

Question 1

What does heparin do?

Answer 1

Blood thinner

Stops blood clotting

Question 2

What is plasma?

Answer 2

Colourless Fluid collected from unclothed blood

Contains clotting factors within it

Question 3

What is serum ?

Answer 3

The colourless fluid collected from clotted blood

Plasma - clotting factors (fibrinogen)

Question 4

What is fibrinogen?

Answer 4

Glycoprotein clotting factor

Helps in formation of blood clots

Question 5

What is peripheral resistance?

Answer 5

Total resistance of arterioles to blood flow

Question 6

What determines peripheral resistance?

Answer 6

Whether arterioles are open or contracted (dilated or constricted)

Question 7

Which areas of the body does hyper plasma viscosity impact and why ?

Answer 7

Periphery because viscosity increases where its colder.

Question 8

What are the components of blood?

Answer 8

Red blood cells, white blood cells, platelets, plasma

Question 9

What is the most commonest cause of increased blood plasma viscosity?

Answer 9

Multiple myeloma - causes increased globulin proteins in the blood

Question 10

What does increased plasma viscosity cause peripheral blood to do?

Answer 10

Get sludging of blood in the periphery

Question 11

What is the name for increased RBCs ?

Answer 11

Polycythaemia

Question 12

What is polycythemia?

Answer 12

Increased red blood cells

Question 13

What is thrombocythaemia?

Answer 13

Increased platelets

Question 14

What is leukaemia?

Answer 14

Increased white blood cells

Question 15

What is the name for increased platelets?

Answer 15

Thrombocythaemia

Question 16

What is the name for increased white blood cells?

Answer 16

Leukaemia

Question 17

When can plasma viscosity be increased In a major and minor way ?

Answer 17

Major increase - multiple myeloma

Minor increase - inflammation (increase in acute phase proteins)

Question 18

Can plasma viscosity be used to measure inflammation ?

Answer 18

Yes as a minor increase in plasma viscosity can be caused by an increase in acute phase proteins which is an indication of inflammation.

Question 19

What are acute phase plasma proteins? Name some examples.

Answer 19

Group of proteins that increase in response to inflammation.

Fibrinogen
Complement factors
C-reactive proteins (CRP)

Question 20

What is the most common measure of inflammation?

Answer 20

C-reactive proteins

CRP

Question 21

How does blood flow when laminar?

Answer 21

In streamlines

Question 22

In laminar blood flow where is the velocity of blood flow the greatest ?

Answer 22

In the centre of the vessel

Question 23

In laminar blood flow where is the velocity the lowest and why?

Answer 23

In the periphery of the vessel due to increased resistance from the vessel wall.

Question 24

How does blood flow when turbulent?

Answer 24

In all directions

Question 25

When does turbulent blood flow occur (5 points)?

Answer 25

- when blood flow increases too great - increased resistance to blood flow - sharp turn - when blood travels over rough surface - when blood passes by an obstruction in a vessel

Question 26

Name a condition when the rate of blood flow becomes too great. What happens to the direction of blood flow ? What can be noticed clinically?

Answer 26

- anaemia - turbulent - murmur

Question 27

What is pulse pressure ? | What is the common value?

Answer 27

Peak systolic pressure - end diastolic pressure | 120mmHg - 80mmHg = 40mmHg

Question 28

What is the mean arterial pressure ? | And what is a normal value for it?

Answer 28

``` MAP = - area under curve of one beat Or Diastolic pressure + 1/3rd of pulse pressure 80mmHg + (40mmHg/3) = 93mmHg ```

Question 29

Below what mean arterial pressure is organ perfusion impaired?

Answer 29

70mmHg

Question 30

Is mean arterial pressure is below 70mmHg, what does this mean?

Answer 30

Organ perfusion is impaired

Question 31

What are the units of pressure ?

Answer 31

Psi | POUNDS PER SQUARE INCH

Question 32

What happens patients arteries as they get older?

Answer 32

Calcify Loose compliance Cant feel a pulse in them

Question 33

What sound on a stethoscope does stenosis of a vessel make make?

Answer 33

BRUIT

Question 34

What can you feel at a stenosed artery?

Answer 34

Thrill (vibration)

Question 35

What are you feeling at a pulse?

Answer 35

Shockwave arriving before blood itself

Question 36

What determines strength of pulse?

Answer 36

- force of left ventricle contraction/ejection of blood | - pulse pressure - greater the pulse pressure, stronger the pulse

Question 37

How is a weak pulse described?

Answer 37

Thready

Question 38

How is an abnormally strong pulse described

Answer 38

Bounding

Question 39

What causes a weak pulse?

Answer 39

- left ventricular failure - aortic valve stenosis - hypovolaemia (severe dehydration/bleeding)

Question 40

What can cause hypovolaemia ?

Answer 40

Severe dehydration | Severe bleeding

Question 41

What causes an abnormally strong pulse?

Answer 41

Bradycardia - widens pulse pressure | Low peripheral resistance (vasodilation) - hot bath, exercise, pregnancy (widens pulse pressure)

Question 42

What does vasodilation do peripheral resistance ?

Answer 42

Decrease it

Question 43

When the pulse is bounding, what happens to the pulse pressure ?

Answer 43

Widens (so bigger number)

Question 44

When the pulse is bounding what happens to the diastolic pressure?

Answer 44

LOWERS

Question 45

When does retrograde flow in the arterial system occur?

Answer 45

When peripheral resistance is high and blood bounces back

Question 46

Where in the body is arterial pressure lower than the heart?

Answer 46

Above the heart

Question 47

Where in the body is arterial pressure and venous pressure greater than the heart?

Answer 47

Below the heart