Thrombosis Flashcards
How does Venous thromboembolism usually manifest?
Deep Vein Thrombosis (DVT) of the leg or pelvis and/or pulmonary embolism
Predisposing factors of venous thromboembolism?
Venous Stasis
Hypercoagulability
Vessel Damage
Known as Virchow’s Triad
What is Pulmonary Embolism?
Usually originates from a DVT that has extended into the popliteal vein (embolised), although sometimes no origin is apparent.
Presentation of DVT?
Leg Swelling
Oedema
Pain and Tenderness
Warmth and Redness
Presentation of PE?
Breathlessness
Chest Pain (Often Pleuritic)
Haemoptysis
In Massive PE - Hypotension and Collapse
Signs: Tachypnoea Tachycardia Small Pleural Effusion Pleural Rub
Risk factors for thromboembolism
Surgical - major surgery in previous 4-6 weeks, lower limb orthopaedic surgery, spinal neurosurgery, surgery for abdominal or pelvic cancer, lower limb plaster cast
Medical - >3 days immobility, lower limb paralysis, heart failure, nephrotic syndrome, active cancer, heparin induced thrombocytopenia, anti-phospholipid syndrome, myeloproliferative disorders
Hormonal - Pregnancy and peurperium, combined oral contraceptive, hormone replacement therapy, ovarian stimulation therapy
Other - Previous VTE/family history/thrombophilia, varicose veins, long distance travel
How is risk of deep vein thrombosis assessed?
Well’s Score
Features and scores of Well’s
Active Cancer - 1 Paralysis or plaster - 1 Bed-rest > 3 days, surgery within 4 weeks - 1 Tenderness along vein - 1 Entire leg swollen - 1 Calf Swollen > 3cm - 1 Pitting oedema (unilateral) - 1 Collateral veins - 1 Alternative diagnosis likely - (-2)
Investigations of DVT/PE
D-Dimer Test Doppler USS CT MRI Venography
PE specifically:
Isotope ventilation/perfusion
CT Pulmonary Angiogram
Treatment of Venous Thromboembolism?
First instance of VTE - Low molecular weight heparin followed by warfarin for 6 months
Further episode of VTE or visceral and life threatening thrombosis - Long term anticoagulation
Massive PE - Embolectomy or fibrinolysis using tissue plasminogen activator (tPA)
VTE in pregnancy - Low molecular weight heparin until 6 weeks after delivery
How does arterial thrombosis usually manifest?
Ischaemic stroke, transient ischaemic attacks (TIAs), acute coronary syndrome and peripheral vascular disease.
What is most arterial thrombosis secondary to?
Atherosclerosis and acute plaque rupture
Risk factors for developing atherosclerosis?
Age Smoking Sedentary Lifestyle Hypertension Diabetes Mellitus Obesity Hypercholesterolaemia
Management of arterial thrombosis?
Primary Prevention:
Lifestyle Modification
Treatment of vascular risk factors
Acute Presentation:
Thrombolysis
Antiplatelet/Anticoagulent drugs
Secondary Prevention
What is Heritable Thrombophilia?
An inherited predisposition to venous thrombosis
