Thrombotic Disorders Flashcards
1
Q
What are the 3 element of haemostasis?
A
- primary haemostasis
- blood coagulation
- fibrinolysis
2
Q
What is involved in primary haemostasis?
A
- vasoconstriction
- vasoadhesion
- platelet aggregation
3
Q
What is involved in blood coagulation?
A
- insoluble fibrin formation
- fribrin cross-linking
4
Q
What is involved in fribrinolysis?
A
- plasminogen is converted to plasmin, by;
- urokinase (extrinsic)
- tissue plasminogen activator tPA (extrinsic)
- XII (intrinsic)
- fribrin is converted to fibrinogen/fibrin degredation products, by;
- plasmin
5
Q
What is a thrombus and thromboembolism?
A
- thrombus- clot arrising in the wrong place
- arterial/venous/microvscular
- thromboembolism- movement of clot along a vessel
6
Q
What is Virchow’s triad for thrombosis?
A
- stasis
- bed rest, travel
- hypercoagulability
- pregnancy, trauma
- vessel damage
- artherosclerosis
7
Q
What are features of arterial thrombus?
A
- ‘white clot’- platelets, fibrin
- ischaemia + infarction
- principally secondary to atherosclerosis
- coronary thrombosis
- MI, unstable angina
- cerebrovascular thromboembolism
- stroke, transiet ischaemia
- peripheral embolism
- limb ischaemia
8
Q
What are the risk factors for arterial thrombosis?
A
- age
- smoking
- sedentary lifestyle
- hypertension
- diabetes
- obesity
- hypercholesterolaemia
9
Q
What is the management for arterial thrombosis?
A
- Primary prevention
- lifestyle modification
- treat vascular risk factors
- Acute presentation
- thrombolysis
- antiplatelet/anticoagulant drugs
- secondary prevention
10
Q
What are features of venous thrombus?
A
- ‘red thrombus’- fibrin, red cells
- rsults in back pressure
- principally due to stasis + hypercoagulability
- limb deep vein thrombosis (DVT)
- pulmonary embolism
- visceral venous thrombosis
- intracranial venous thrombosis
- superficial thrombophlebitis
11
Q
What are risk factors for venous thrombosis?
A
- inc. age
- surgery
- obesity
- pregnancy
- hormonal therapy
- tissue trauma
- family history
- immobility
- systemic disease
- cancer
- myeloproliferative neoplasm (MPN)
- autoimmune disease (e.g. IBD, connective tissue disease, antiphospholipid syndrome)
12
Q
What are the investigations for venous thrombosis?
A
- pretest probabilty scoring
- Wells score
- Geneva score
- labratory testing if pretest probability is low
- D-dimer
- Doppler US
- ventilation/perfusion scan (V/Q)
- CT pulmonary angiogram
13
Q
What is the management for venous thrombosis?
A
- prevent clot extension
- prevent clot embolisation
- prevent clot recurrance in long term treatment
- anticoagulants
- LMWH
- Coumarins (warfarin)
- DOACs
- thrombolysis
- e.g. massive PE
14
Q
What is heritable thrombophilia?
A
- an inheritied predisposistion to venous thrombosis
- Common
- Factor V Leiden
- prothrombin
- rare
- antithrombin deficiency
- protein C deficiency
- protein S deficiency
15
Q
What are features of macrovascular thrombus?
A
- platelets and/or fibrin
- results in diffuse ischaemia
- principally in Disseminated Intravascular Ischaemia (DIC)
