Circulation

Question 1

How does the inside of a normal artery look like?

Answer 1

Endothelial cells on the basal lamina which are smooth muscle cells
Surrounded by interstitial collagen fibres around it.

Question 2

What is serum?

Answer 2

Blood plasma without clotting factors

Question 3

Where are clotting factors made?

Answer 3

Mainly produced by the liver
Also produced by endothelial cells

Question 4

What is an amplification system?

Answer 4

It causes fibrin to increase and TF to reduce

Question 5

What is an overview of an amplification system?

Answer 5

Prothrombin into thrombin
Which causes fibrinogen into fibrin

Question 6

What triggers the clotting cascade?

Answer 6

Exposure of interstitial collagen and exposure of TF (tissue factors)

Question 7

What are the 2 mechanisms of clotting?

Answer 7

Thrombosis
Clotting

Question 8

What does plasma consist of?

Answer 8

Water and numerous proteins

Question 9

What is serum?

Answer 9

Plasma without clotting factors

Question 10

How are clotting factors named?

Answer 10

Roman numerals
I.e clotting factor VIII

Question 11

What does thrombin do?

Answer 11

Covert soluble firbrinogen into insoluble fibrin

Question 12

What happens in the clotting cascade?

Answer 12

Damage causes the release of tissue factors from smooth muscle
This promotes change of prothothrombin to thrombin which causes fibrinogen to become fibrin

Question 13

What triggers the release of tissue factors?

Answer 13

Exposure of interstitial collagen to the serum due to trauma

Question 14

How does the clotting cascade keep going?

Answer 14

Most clotting factors are serine proteases
An activated serine molecule acts as a precursor for the next clotting factor

Question 15

Where are platelets made?

Answer 15

Bone marrow from megakaryocytes

Question 16

Why is division in megakaryocytes?

Answer 16

Nuclear division of the cell therefore its a huge cell with many nuclei
Platelets bud off the cytoplasm

Question 17

How do platelets cause clotting?

Answer 17

Platelets adhere together to bridge close the gap in vessels by becoming sticky when activated

Question 18

What are the types of coagulation?

Answer 18

Thrombus formation
Clot formation

Question 19

What is thrombus formation?

Answer 19

Occurs when blood is flowing
Platelets and fibrin combine to form a platelet thrombus on the blood vessel wall

Question 20

What is a clot formation?

Answer 20

Network of fibrin and red blood cells formed. By exposure to collagen and stagnant blood

Question 21

What is haemostasis?

Answer 21

Stopping bleeding

Question 22

Why does vasoconstriction happen in injury?

Answer 22

It decrease the size of vessels consequently decreases amount of blood loss

Question 23

Why do clots form?

Answer 23

Prevent excessive bleeding
Allows for formation of a thrombus

Question 24

What is granulation tissue?

Answer 24

When new vessels grow into the wound/clot to keep it oxygenated
The new vesssel is called granulation tissue

Question 25

How is a thrombus removed?

Answer 25

Plasminogen in the blood gets converted to plasmin This cuts fibrin into small fragments

Question 26

What is thrombolysis?

Answer 26

Removing of a thrombus by removing fibrin

Question 27

What is the fibrinolytic system?

Answer 27

A system which removes fibrin and stops thrombin from propagating which is in balance with the clotting system

Question 28

When is thrombosis and clotting normal?

Answer 28

Stop bleeding during metabolism Wound healing

Question 29

What are the 3 main causes of thrombosis?

Answer 29

Changes of the internal surface of a vessel Change in blood flow pattern Change in blood constituents

Question 30

What is Virchows triad?

Answer 30

1. Changes in the intimal surface of a vessel 2. Changes in the pattern of blood flow 3. Changes in the blood constituents

Question 31

What is an amplification system?

Answer 31

Clotting factors activates other clotting factors to enhance the clotting system

Question 32

When is thrombosis normal?

Answer 32

Cut

Question 33

When is thrombosis abnormal

Answer 33

No cut or injury

Question 34

How does smoking affect thrombosis?

Answer 34

It makes platelets more sticky Hence a thrombosis is likely to occur

Question 35

What is atheroma?

Answer 35

Disease of coronary artery which results in build up of lipid under intimal surface. (In between outermost layers of artery)

Question 36

How does atheroma cause problems with thrombosis?

Answer 36

Causes slowed blood flow hence increase chances of clotting Or the lipid ruptures the artery which exposes the collagen to platelets and fibrin causing thrombosis This also causes blood to stop flowing and develop a clot

Question 37

What are the lines of Zahn?

Question 38

What is ischaemia?

Answer 38

Poor blood flow

Question 39

How does ischaemia cause hypoxia?

Answer 39

Poor blood flow means less oxygen in tissues

Question 40

What is an infarct?

Answer 40

Localised area of dead tissue due to hypoxia killing cells Ischaemic necrosis

Question 41

What is an embolism?

Answer 41

Mass of material in blood vessels which can block lumens Typically clots or thrombi

Question 42

What is a thromboembolism?

Answer 42

Thrombi or clot which embolises

Question 43

How can a pulmonary embolism arise?

Answer 43

Slow flow in leg vein causes clot to form. Clot travels through the vein through the heart and into the lungs

Question 44

Why must you check your syringe for air bubbles.

Answer 44

Can cause an air embolism

Question 45

What is circulatory shock?

Answer 45

Bad circulatory failure as organs can’t get sufficient diffused blood.

Question 46

What is normal bp?

Answer 46

120/80 Much lower venous pressure

Question 47

When is it shock?

Answer 47

Low bp Fast pulse

Question 48

Explain what happens in shock?

Question 49

How does septicaemia chase septic shock?

Answer 49

Infection in blood causes vasodilation so blood begins to pool and doesn’t spread around the body

Question 50

What are the main complications of shock?

Answer 50

Decreased perfusion to organs like kidneys or brain.

Question 51

What are the 3 main causes of circulatory shock?

Answer 51

Hypovolaemic Septic Cardiogenic

Question 52

What surrounds the basal lamina of vessels?

Answer 52

Elastic tissue

Question 53

How is blood pressure maintained?

Answer 53

Enough blood in the system Smooth muscles gave enough tone Heart pumping blood

Question 54

What is hypovolaemic shock?

Answer 54

Haemorrhage Less systemic blood Hence decrease pressure Vessels collapse Blood can’t enter heart Now blood can’t go around body Systemic blood pressure drops

Question 55

What do cartoid sinuses do?

Answer 55

Sense lower systemic pressure Upregulates sympathetic system Rapid breathing and fast pulse to try and increase bp

Question 56

What happens in Cardiogenic shock?

Answer 56

Heart can’t pump blood as heart is failing Blood pressure drops Pulse increases

Question 57

What happens in septic shock?

Answer 57

Too much Vasodilation occurs as there’s an infection in blood Too much dilation not enough blood in circulation

Question 58

What happens in severe septic shock?

Answer 58

Muscles in heart lose their tone as they don’t get enough oxygen and nutrients and leads to wastage or acidosis Heart rate is slowed hence bradycardia

Question 59

What pressure drops in septic shock?

Answer 59

Arterial as vasodilation causes it

Question 60

What pressure drops in hypovalemic ?

Answer 60

Venous

Question 61

What are complications of shock?

Answer 61

Brain injury as decreased perfusion to brain (MOST IMP AND HAPPENS FISRT ISH) Decreased perfusion of kidney