DVT + thromboembolism Flashcards
Rfs
age pregnancy synthetic oestrogen trauma surgery immobility thrombophilia past DVT cancer obesity
prevention
stop pill 4weeks pre-op
mobilise early
LMWH prophylaxis
graduated compression stockings
pathophysiology (Virchow’s triad)
changes in vessel wall (injury)
changes in pattern of blood flow (venous stasis)
changes in constituency of blood (hyper coagulability)
venous thrombosis often occurs in normal vessels, unlike arterial thrombosis
presentation
non-specific
calf warmth, tenderness, swelling, erythema.
mild fever, pitting oedema
D-dimer
Sensitive but not specific test for DVT
Its a fibrin degradation product, present in blood after a clot is degraded by fibrinolysis
- normal excludes Dx
- if raised –> do USS
Compression US
test of choice
vein can be squashed flat if full of blood, can’t if theres a clot
Treatment aim
to prevent further thrombosis + PE while resolution of venous thrombi occurs by natural fibrinolytic activity
subcut LMWH
1st line of treatment. Use OD until INR is 2.5
immediate anticoagulant effect
doesn’t break clot down but stops it growing
heparin binds to antithrombin –> conformational change, increasing inhibitory activity of antithrombin (at least 5000 fold!)
what do you start simultaneously with heparin?
warfarin - an oral anticoagulant
acts by interfering with vitamin K metabolism
SE: bleeding
what is post-thrombotic/phlebitic syndrome, and how to prevent it?
pain, swelling and skin changes- can lead to a permanently swollen limb - ulceration
compression stockings
thromboembolism
obstruction of a blood vessel by a clot thats become dislodged from another site in the circulation
may plug a vessel in the lungs, brain, GI tract, kidneys or leg
Tx thromboemboism
anticoagulants, aspirin or vasodilators
