Deep vein thrombosis is a blood clot in a deep vein, most often in the leg or pelvis. Its main danger is that part of the clot breaks off and travels to the lungs as a pulmonary embolism.
Key symptoms
- Swelling of one leg, often the calf
- Pain or tenderness, worse when standing or walking
- Warmth and redness of the leg
- Recent surgery, immobility, cancer, pregnancy or long travel
What you find on exam
- Compare calf size; more than 3 cm larger on one side is significant
- Tenderness along the deep veins
- Pitting edema and visible surface veins on the affected leg
- Check pulses, color and skin to rule out arterial problems or cellulitis
Tests
- Wells score to estimate the probability
- D-dimer if probability is low; a normal result helps rule it out
- Compression ultrasound of the leg veins to confirm
- Blood count, kidney function and coagulation tests before anticoagulation
Treatment basics
- Anticoagulation, usually a direct oral anticoagulant such as apixaban or rivaroxaban
- Heparin or enoxaparin when oral agents are not suitable, such as in pregnancy or severe kidney disease
- At least 3 months of treatment; longer if the cause persists
- Walking is encouraged once anticoagulation has started
- Prevention in hospital: early mobility, compression devices, preventive anticoagulants
Red flags
- Sudden breathlessness or chest pain
- Very swollen, blue or cold leg
- Bleeding while on anticoagulants
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Sources: NCCPA PANCE Content Blueprint; NBOME COMLEX-USA clinical presentations; AAMC Core Entrustable Professional Activities (Core EPAs). Written by Making Synapses. Making Synapses is not affiliated with these organizations.