Deep Vein Thrombosis Flashcards
What is deep vein thrombosis?
Formation of blood clot in the deep veins of a limb
Pathophysiology of deep vein thrombosis
Virchow’s triad
Abnormal blood flow
- immobility
Abnormal blood components
- smoking
- sepsis
- malignancy
Abnormal vessel wall
- atheroma
- inflammatory response
- direct trauma
What are risk factors for deep vein thrombosis?
Increasing age Previous VTE Smoking Pregnancy Recent surgery Prolonged immobility Hormone replacement
Clinical features of DVT
65% asymptomatic
Unilateral leg pain
Swelling - measure 10cm below tibial tuberosity - >3cm = swollen
Mild fever
Prominent superficial veins
What is the Wells’ score?
Identifies risk of DVT
Criteria
- active cancer
- bedridden > 3days OR major surgery in last 4 weeks
- calf swellingn >3cm
- collateral superficial veins present
- entire leg swollen
- localised tenderness alonf deep venous system
- pitting oedema
- paralysis/paresis or recent plaster of leg
- previously documented DVT
Score = 1
- DVT unlikey
- D-dimer test to exlcude
Score >1
- DVT clinically likely
- confirmed via ultrasound
Management of DVT
DOACs (contraindicated in pregnancy)
- apixaban
- rivaroxaban
LMWH
- fondaparinux
- enoxaparin
- dalteparin
Differentials for DVT
Muscle strain/tear
Lymphangitis
Cellulitis
What is phlegmasia cerulea dolens?
Painful blue leg swelling
When DVT compresses arterial supply
What investigations are done for potential DVT?
Bloods
- FBCs
- U+Es (treatments are renally cleared)
- LFTs
- INR
- aPTT
Doppler venous flow
D-dimer
What does a D-dimer show?
Low = definitely not DVT
High = requires further investigations
What can cause a high D-dimer?
MI
DIC
Stroke
Pregnancy
