Thrombosis and embolism

Question 1

What is normal flow of blood in vessels?

Answer 1

Laminar flow, that is smooth and ordered

Question 2

What is abnormal flow of blood?

Answer 2

Turbulent flow or stasis of blood

Question 3

Name the components of Virchow’s triad

Answer 3

1. change in the wall of blood vessel, 2. change un the pattern of blood flow, 3. change in the blood constituents

Question 4

Define thrombus

Answer 4

solid mass from constituents of blood within the vascular system during life within the vascular system

Question 5

What is the pathogenesis of thrombus formation?

Answer 5

endothelial injury, stasis of blood or turbulent blood flow, hyper coagulability

Question 6

Describe the sequence in thrombus formation

Answer 6

endothelium is lost and sticky surface of the plaque is exposed, fibrin and platelets deposit on the surface of the plaque and exposed collagen, fibrin meshwork is formed and RBC become trapped within this network, this gives characteristic lines of Zahn appearance, this leads to further turbulent flow, damage to endothelium and propagation of thrombus

Question 7

What are lines of Zahn?

Answer 7

alteration of fibrin network interspersed with RBC or platelets, this form characteristic appearance of red and white lines

Question 8

What are the risk factors for thrombosis?

Answer 8

Hypercholesterolaemia, hypercoagulability

Question 9

What is mural thrombus ?

Answer 9

Thrombus adhered to one side only, in endothelium of heart or aorta

Question 10

What is parietal thrombus?

Answer 10

Thrombus that adhere to one side only, to the wall of arteries

Question 11

What are the possible outcomes of thrombosis ?

Answer 11

resolution, organisation and recanaisation, propagation, death

Question 12

What is resolution?

Answer 12

The clot dissolves either spontaneously or due to thrombolysis

Question 13

What is organisation and recanalisation?

Answer 13

The process in which the thrombus is stabilised, it does not propagate, blood flow is restored by formation of new blood vessels in the fibrous tissue

Question 14

What are the types of embolism based on the locations or the point of entry?

Answer 14

arterial, paradoxical, venous

Question 15

What is arterial or systemic thromboembolism ?

Answer 15

Embolus that is circulating in the arterial circulation, most commonly formed in the heart, it can cause occlusion in any part of the body, the end result is infarction or ischaemia

Question 16

What is paradoxical embolus?

Answer 16

Embolus that arise fromm venous circulation and crossed to arterial circulation, it is usually due to septal defect

Question 17

What is venous embolus ?

Answer 17

Embolus that travels in venous circulation, most commonly arise in deep veins and causes pulmonary embolism

Question 18

What are the risk factors for embolism?

Answer 18

Heart failure, post-op, postpartum, severe trauma, burns, nephritic syndrome, oral contraceptive pills, age, obesity, bed rest and immobilisation, family history and previous emboli

Question 19

What are the types of emboli based on the material?

Answer 19

Fat, gas, air, amniotic fluid, trophoblast, tumour, septic material, bone marrow, foreign bodies

Question 20

What us fat embolus?

Answer 20

Fat macromolecules that are broken off and traveling in the systemic circulation, they arise after major fractures, soft tissue injuries, orthopaedic procedures, severe burns, bone marrow biopsy, liposuction, fatty liver, prolonged corticosteroid therapy, end results is syndrome of fat embolism

Question 21

What is the syndrome of fat embolism?

Answer 21

Results from fat embolus occlusion, breathlessness, respiratory failure, cerebral dysfunction and petechial rush

Question 22

What is gas embolus?

Answer 22

Bubble of gas traveling around body in circulation, caused by decompression sickness (gas comes out of solution on decompressurisation), the symptoms can very from pain, rashes to paralysis and death, e.g. N2 gas from underwater decompression

Question 23

What is air embolus?

Answer 23

Air in the circulation, arise from head and neck wounds, surgeries and CV lines, again various symptoms

Question 24

What is tumour embolism?

Answer 24

When parts of tumour break off and travel around the body in blood, it is possible cause of spread of tumours

Question 25

What is trophoblast embolism?

Answer 25

Parts of placenta breaks off and lodge usually in lungs

Question 26

What is septic embolus?

Answer 26

Embolus made of septic material that breaks off, can lead to infective endocarditis, aneurysm

Question 27

What is amniotic fluid embolism?

Answer 27

rare, material from child to maternal bloodstream, causes collapse of mother during pregnancy, there is immune system reaction

Question 28

What is bone marrow embolism?

Answer 28

Fatty tissue or bone marrow cells in the blood, after fractures, or CPR

Question 29

What is foreign bodies embolism?

Answer 29

What material like sutures, cannula tips etc travel around blood