Pathophysiology of Coagulation + Haemostasis

Question 1

What is thrombosis?

Answer 1

Pathological formation of a intravascular blood clot

Question 2

What are the 3 things that cause thrombosis?

Answer 2

Disruption of blood flow (stasis)
Endothelial cell damage
Hypercoagulable states

Question 3

What may cause disruption to blood flow?

Answer 3

Immobilisation (flight, bedrest)
Cardiac wall dysfunction
Aneurysm
AF

Question 4

What may cause endothelial cell damage?

Answer 4

Inflammation
Cigarette smoke
Cytokines
Atherosclerotic plaque

Question 5

What may cause hypercoagulable states?

Answer 5

Any disease process that leads to an increased blood clot formation

Question 6

What are hypercoagulable states because of?

Answer 6

Excessive procoagulant factors or defective anticoagulant

Question 7

What are hypercoagulable states?

Answer 7

Inherited or acquired disease

Question 8

What is the classic presentation of hypercoagulable states?

Answer 8

Recurrent DVT or DVTs at young age

Question 9

What does Alteplase do?

Answer 9

Break down clots

Question 10

When should Alteplase be used after an ischaemic stroke?

Answer 10

Only if it can be within 4.5hrs of symptom onset

Question 11

What is the 1st choice for the treatment of a venous thrombus?

Answer 11

Rivaroxaban
Apixaban

Question 12

What are venous clots the most common cause of?

Answer 12

Stasis of blood

Question 13

Where is the most common site for venous thrombus?

Answer 13

Deep veins on lower limb

Question 14

What are venous thrombus mostly made of?

Answer 14

Fibrin

Question 15

What are arteriole thrombus mostly made of?

Answer 15

Platelets

Question 16

What are arteriole thrombus mostly due to?

Answer 16

Endothelial damage

Question 17

Why is aspirin used for arteriole thrombus?

Answer 17

As it is an inhibitor of platelet aggregation

Question 18

What is an embolism?

Answer 18

Blockage caused by anything that breaks off = emboli

Question 19

What is a pulmonary embolism?

Answer 19

Intravascular mass that travels + occludes pulmonary blood vessels

Question 20

What are the functions of thrombin?

Answer 20

Acts on fibrinogen to produce fibrin monomers
Activates 13a
Strengthens blood clot

Question 21

What are the functions of plasmin?

Answer 21

Breaks down clot

Question 22

How does plasmin break down the clot?

Answer 22

Cleaves fibrin + fibrinogen into FDPs
= form fragments = D-dimers

Question 23

What is thrombin switched off by?

Answer 23

Natural anticoagulant antithrombin3
= limits clot formation

Question 24

What are the 3 main stages of platelet aggregation?

Answer 24

Adhesion
Release reaction
Aggregation