Deep Vein Thrombosis and Pulmonary Embolism Flashcards
What is meant by DVT?
Deep Vein Thrombosis - A thrombus formed in the deep venous circulation, usually in the legs
What is meany by a PE?
Pulmonary Embolism - A thrombus that has embolised and lodged in the pulmonary circulation
Where in the veins do thromboses usually form in DVT?
In the venous valve pockets, behind the opening valve leaflets
What is meant by proximal DVT?
Any clot that involves the popliteal vein or higher
What s meant by distal DVT?
Any clot that forms below the popliteal artery
What is the mortality rate for a pulmonary embolism?
17.5% at 3 months
What is the mortality rate for DVT?
0.5 - 5% at 3 months
What occurs in 30% of proximal DVTs after treatment?
Post Thrombotic Syndrome
What are the 3 points of Virchow’s triad?
Hypercoagulability
Circulatory stasis
Endothelial injury
What are some causes of Hypercoagulablity?
Malignancy
Pregnancy
Paripartum period (Period surrounding birth)
Oestrogen therapy
Inflammatory Bowel Disease
Sepsis
Thrombophilia
What are some causes of circulatory stasis?
Left ventricular dysfunction
Immobility or paralysis
Venous insufficiency
Varicose veins
venous obstruction
What are some causes of endothelial injury?
Venous disorders
Valve damage
Trauma
Surgery
Indwelling catheters
What are some textbook presentations of DVT?
Painful swollen limb with redness and heat
tenderness along the vein
Sub-acute development
No other causes
What are some textbook presentations of Pulmonary Embolism?
Sudden Shortness of Breath with pleuritic pain
Collapse
Haemoptysis
Hypoxia and tachycardia
Low blood pressure
How does the D-dimer test work?
It tests for the breakdown of cross-linked fibrin, showing the presence of clotting
How should D-dimer results be interpreted?
The test has a high negative predicted value and a low positive predicted value, meaning the test is very good for saying there’s no clot, but a positive result cannot be interpreted
What should be done in a patient with a negative D-dimer test result?
No further testing
What should be done in a patient with a positive D-dimer test and a high risk score?
A duplex scan
What are the tests for a pulmonary embolism?
A CT pulmonary angiogram or ventilation perfusion scanning
How is the severity of DVT decided?
Through clinical assessment of severity
How is the severity of PE decided?
By calculating the patients PESI score
What is the management for DVT?
Oral anti-coagulants - Some patents can have thrombolysis but this is only at specialist services
Which is the management for PE?
High risk - Thrombolysis then oral anti-coagulation
Low risk - Oral anti-coagulants
What are the main choices of anti-coagulant?
Apixaban or Rivaroxiban - 1st line therapy
Warfarin - rarely used as direct oral anti-coagulants
Low Molecular Weight Heparin - Used in patients with Active cancer + PE
