Thrombotic Disorders Flashcards
what are the elements of haemostasis?
- primary haemostasis
- blood coagulation
- fibrinolysis
components of primary haemostasis
- vasoconstriction
- platelet adhesion
- aggregation
components of coagulation
- insoluble fibrin formation
- fibrin cross-linking
Virchow’s triad
causes of:
- stasis: bed rest, travel
- hypercoagulability: pregnancy, trauma
- vessel damage: atherosclerosis
features of arterial thrombus
- forms ‘white clot’ - platelets and fibrin
- results in ischaemia and infarction
- principally secondary to atherosclerosis
what are some examples of arterial thromboembolism?
- coronary thrombosis e.g. MI, unstable angina
- cerebrovascular thromboembolism e.g. stroke, TIA
- peripheral embolism e.g. limb ischaemia
risk factors for arterial thrombosis
- age
- smoking
- sedentary lifestyle
- hypertension
- diabtetes mellitus
- obestiy
- hypercholesterolaemia
arterial thrombosis management
primary prevention, acute, secondary prevention
- primary prevention: lifestyle modification, treatment of vascular risk factors
- acute: thrombolysis, antiplatelet/anticoagulant drugs
- secondary prevention: aspirin
features of a venous thrombus
- ‘red thrombus’ - fibrin and red cells
- results in back pressure
- principally due to stasis and hypercoagulability
examples of venous thromboembolism
- limb DVT
- pulmonary embolism
- visceral venous thrombosis
- intracranial venous thrombosis
- superficial thrombophlebitis
risk factors for venous thrombosis
- increasing age
- preganancy
- hormonal therapy: COCP/HRT
- tissue trauma
- immobility
- surgery
- obesity
- systemic disease
- family history
which systemic diseases are associated with increased risk of venous thrombosis?
- cancer
- myeloproliferative neoplasm (MPNs)
- autoimmune disease: IBD, connective tisse disease e.g. SLE, antiphospholipid syndrome: arterial and venous thrombosis
what investigations are performed to diagnose a venous thrombosis?
- Pretest probability scoring: Wells score, Geneva score
- lab testing if pretest probability low: D-dimer
- imaging: doppler US, ventilation/perfusion scan (V/Q), CT pulmonary angiogram
venous thrombosis treatment
- anticoagulants: LMWH, coumarins (warfarin), DOACs
- thrombolysis only in selected cases e.g. massive PE
what are some common and rare causes of heritable thrombophilia?
Common:
- factor V leiden
- prothrombin G20210A
Rare:
- antithrombin deficiency
- protein C deficiency
- protein S deficiency
features of microvascular thrombus
- platelets and/or fibrin
- results in diffuse ischaemia
- principally in disseminated intravascular coagulation (DIC)
what conditions can cause DIC?
- septicaemia
- malignancy
- eclampsia
what are complications of DIC?
- tissue ischaemia > gangrene
- organ failure
DIC treatment
Management of DIC is primarily focused on treating the underlying cause. Supportive care is also essential to manage symptoms and prevent complications. This may include transfusions of platelets or clotting factors, and in some cases, anticoagulation therapy may be necessary.