Deep Vein Thrombosis (DVT)
This is where a clot develops in the venous system of the lower legs. Risk factors of it include:
Immobility, Recent surgery, Long-haul flights - Very important to ask about this!
Pregnancy
COCP/HRT
Cancer, thrombophilia, polycythaemia, lupus, previous hx
Patients present with:
Unilateral warm, swollen, tender calf/thigh
Mottled skin
Dilated superficial veins
Pitting oedema
N.B. Measure calf circumference 10 cm below tibial tuberosity and compare. Difference > 3 cm makes DVT more likely.
Complications - PE, Stroke (if septal defect), Venous insufficiency
Differentials - Cellulitis, Ruptured baker’s cyst
Wells Score
This score is used to predict the likelihood of a DVT.
Investigations
Well's score of 0 = DVT unlikely
Do D-dimer
Negative excludes DVT and no further imaging needed
Positive calls for further imaging i.e. Doppler US
Well's score of 1-2 = DVT likely
Do high-sensitivity D-dimer
Negative excludes DVT and no further imaging needed
Positive calls for further imaging i.e. Doppler US
Well's score 3+ = DVT likely
D-dimer + Doppler US
D-dimer is done to risk-stratify these patients
If US positive, treat w/anticoagulation regardless of D-dimer result
N.B. All unprovoked DVTs should be investigated further for any underlying pathology e.g. CT CAP for cancer.
Management
1st line - DOAC e.g. Rivaroxaban, Edoxaban. This is given for 3 months if a provoked PE, or 6 months if an unprovoked PE. If patient is having recurrent PE's, they should be prescribed a DOAC for life.
N.B. LMWH/UFH is usually preferred if the patient has renal impairment.
If a massive DVT, thrombectomy may be done.
IVC filter can be used to reduce the risk of the DVT embolising to cause a PE if recurrent.
Prophylaxis - LMWH, Compression stockings/Pneumatic compression (contraindicated in peripheral arterial disease).
N.B. The compression stockings/pneumatic compression are mechanical forms of thromboprophylaxis as they prevent venous stasis by promoting ouflow. Important to understand this as it does the same resulting job as prophylactic medication, but just in a different way.


