Deep Vein Thrombosis and Pulmonary Embolism Flashcards
what is a thrombus?
a clot arising in the wrong place
what is a thromboembolism?
movement of a clot along a vessel
what is virchow’s triad?
> stasis
hypercoagulability
vessel damage
give some examples of venous thromboembolism
> limb deep vein thrombosis > pulmonary embolism > visceral venous thrombosis > intracranial venous thrombosis > superficial thrombophlebitis
what is a venous thrombus principally due to?
stasis and hypercoagulability
what cells make a venous red thrombus?
fibrin and red cells
what vessel does a white clot form?
arteries
what cells make up a white thrombus?
platelets and fibrin
what results from an arterial thrombus?
ischaemia and infarction
what are the symptoms and signs of deep vein thrombosis?
> unilateral limb swelling > persisting discomfort > calf tenderness > warmth > redness > it may be clinically silent
what are the symptoms and signs of a pulmonary embolism?
> pleuritic chest pain > breathlessness > haemoptysis > tachycardia > pleural rub on auscultation
what are the signs and symptoms of massive pulmonary embolism?
> severe sudden onset dyspnoea > collapse > central cyanosis > tachycardia > low blood pressure > raised JVP > altered heart sounds > may cause sudden death
what is post-phlebitis syndrome?
a potential long-term consequence of long-term DVT causing: swelling, discomfort, pigmentation and ulceration.
what is a potential long term consequence of pulmonary embolism?
pulmonary hypertension
name some risk factors of venous thrombosis
> increased age > tissue trauma > immobility > obesity > smoking > cancer > pregnancy > exogenous oestrogen
what is heritable thrombophilia?
an inherited predisposition to venous thrombosis
what is the most prevalent heritable thrombophilia?
factor v leiden
what would you use to diagnose deep vein thrombosis
> clinical assessment
blood test: d dimer
compression ultrasound
what would you use to diagnose pulmonary embolism?
> clinical assessment > d-dimer > isotope ventilation > perfusion scan > CT pulmonary angiogram
how can you prevent venous thrombosis embolism in hospital?
> early mobilisation
anti-embolism stockings
daily injections of low molecular weight heparin
what do anti-embolism stockings provide at the ankle?
18mmHg
what do anti-embolism stockings provide at the mid-calf?
14mmHg
what do anti-embolism stockings provide at the upper thigh?
8mmHg
what are the indications for graduated compression stockings?
> prevention of DVT > chronic venous insufficiency > oedema > lymphoedema > prevention of post-phlebtic syndrome