Session 5

Question 1

What is Haemostasis?

Answer 1

The bodys response to stop bleeding and loss of blood

Question 2

What does successful Haemostasis depend on?

Answer 2

Vessel wall
Platelets
Coagulation system
Fibrinolytic system

Question 3

How do blood vessels aid Haemostasis?

Answer 3

They construct to limit blood loss

Question 4

How do platelets aid Haemostasis?

Answer 4

They adhere to the damaged vessel wall and to each other

Form a platelet plug

Question 5

How can the coagulation system be regulated?

Answer 5

Thrombin is positive feedback for factor V, VIII and XI

Anti thrombin III and alpha 1 anti trypsin are inhibitors

Question 6

What can cause thrombosis?

Answer 6

An inherited deficiency in antithrombin III

Question 7

What is fibrinolysis?

Answer 7

The breakdown of fibrin by plasmin

Question 8

When is fibrinolytic therapy used?

Answer 8

Used as clot busters eg coronary artery occlusion

Question 9

What is thrombosis?

Answer 9

The formation of a solid mass of blood within the circulatory system during life.

Question 10

What is Virchow’s Triad?

Answer 10

Changes in blood flow
Changes in vessel wall
Changes in blood components
All can lead to a thrombsis.

Question 11

What are the features of an Arterial thrombi?

Answer 11

Pale
Granular
Lines of Zahn
Low cell content

Question 12

What are the features of a Venous thrombi?

Answer 12

Deep red
Soft
Gelatinous
High cell content

Question 13

What are some of the effects of an arterial thrombi?

Answer 13

Ischaemia
Infarction
Dependent on site and collateral circulation

Question 14

What are some of the effects of a Venous thrombi?

Answer 14

Congestion
Oedema
Ischaemia (If the tissue pressure due to an oedema becomes higher than the arterial pressure)
Infarction

Question 15

What are the outcome of thrombosis?

Answer 15

Lysis
Propagation
Organisation
Recanalisation
Embolism

Question 16

What happens in Lysis of a thrombus?

Answer 16

Complete dissolution, blood flow is reestablished

Most likely with small thrombi

Question 17

What happens in Propagation of a thrombus?

Answer 17

There is progressive spread of thrombosis, distally in arteries and proximally in veins

Question 18

What happens in organisation of a thrombus?

Answer 18

A reparative process with ingrowth of fibroblasts and capillaries
The lumen is still obstructed

Question 19

What happens in recanalisation of a thrombus?

Answer 19

Incomplete blood flow is established through channels in the organising thrombus

Question 20

What happens in an Embolism of a thrombus?

Answer 20

Part of the thrombus breaks off and travels in the blood stream to lodge at a distant site.

Question 21

What is an embolism?

Answer 21

The blockage of a blood vessel by solid, liquid or gas at a site distant from its origin.

Question 22

What are some of the types of emboli?

Answer 22

Thrombo emboli
Air
Amniotic fluid
Nitrogen

Question 23

What organ is effected by thromboembolisms from systemic veins?

Answer 23

The lungs.

Question 24

How can thromboembolisms happen in the legs?

Answer 24

There is a thrombus in the Atheromatous Abdominal Aorta

Question 25

What are the 3 categories of Pulmonary Embolism?

Answer 25

Massive Major Minor Recurrent

Question 26

What are the effects of a massive PE?

Answer 26

60% reduction in blood flow. | Rapidly fatal

Question 27

What are the effects of a major PE?

Answer 27

Medium sized vessel blocked. Shortness of breath Cough Blood stained sputum

Question 28

What are the effects of a minor PE?

Answer 28

Small peripheral artery blocked | Asymptomatic or minor shortness of breath

Question 29

What are the effects of recurrent PEs?

Answer 29

Pulmonary hypertension

Question 30

What are the risk factors for deep vein thrombosis?

Answer 30

``` Immobility Post op Pregnancy Oral contraceptives Severe burns Cardiac failure ```

Question 31

What is the treatment for DVT?

Answer 31

Intravenous Herparin - fast acting anticoagulant as co factor for anti thrombin III Oral Warfarin long term interferes with synthesis of vitamin K dependent clotting factors

Question 32

What are the signs of a fat embolism?

Answer 32

Rash Shortness of breath Confusion

Question 33

How can a cerebral embolism occur?

Answer 33

Atrial fibrillation can cause stasis and a thrombus in the left heart so passes to the brain.

Question 34

What is an Iatrogenic embolism?

Answer 34

One due to medial treatment eg air from an injection

Question 35

What is a Nitrogen embolism?

Answer 35

Nitrogen bubbles form in the blood with rapid decompression - the bends

Question 36

What is Disseminated Intravascular Coagulation?

Answer 36

A pathological actiation of coagulation mechanisms, occurs in response to some diseases. Small clots form in body and use all clotting factors so have abnormal bleeding.

Question 37

What can trigger Disseminated Intravascular Coagulation?

Answer 37

Infection Trauma Liver disease Obstretric complication

Question 38

What type of disease is Haemophilia?

Answer 38

X linked recessive

Question 39

What factor is missing in type A Haemophilia?

Answer 39

Factor VIII

Question 40

What factor is missing in type B Haemophilia?

Answer 40

Factor IX

Question 41

What type of mutation causes Haemophilia?

Answer 41

A nonsense point mutation

Question 42

What are the effects of Haemophilia?

Answer 42

``` Haemorrhage into major joints Muscle bleeds Necrosis of nerves Haemorrhage into urinary tract All cause pain ```

Question 43

How can Haemophilia be managed?

Answer 43

Self administered factor replacement therapy

Question 44

What is Thrombocytopenia?

Answer 44

The platelet count is way below the reference range

Question 45

What causes Thrombocytopenia?

Answer 45

Failure of platelet production Increased platelet destruction Sequestering of platelets

Question 46

What diseases usually accompany Thrombocytopenia?

Answer 46

Bone marrow dysfunctions