The formation of a clot in a deep vein, usually located in the lower extremities or pelvis, is known as Deep Vein Thrombosis (DVT).
Aetiology:
The formation of a clot in a deep vein is believed to be precipitated by Virchow's Triad:
Venous Stasis - This refers to the factors that cause a reduction in blood flow, such as immobility, congestive cardiac failure, dehydration and venous obstruction.
Endothelial Injury - Trauma, inflammation and previous thrombosis can lead to injury to the endothelium, the layer of cells that line the interior surface of blood vessels.
Hypercoagulable State - Malignancy, oestrogen therapy, surgery and abnormalities of the clotting cascade can result in a hypercoagulable state.
Symptoms:
The most common symptoms of Deep Vein Thrombosis are pain, swelling, erythema, warmth and pitting oedema.
Signs:
Homan's Sign is a reliable indicator of a clot. It is defined as an increase in pain on dorsiflexion in the calf; a sign indicative of DVT.
Investigations:
Bloods: D-dimer
Imaging: Ultrasound Doppler studies, venogram.
Treatment:
Medical: Low molecular weight heparin, oral anticoagulant, support stockings and investigation of the underlying cause along with IVC filter.
Complications:
Complications can include pulmonary embolism, thrombus extension, post thrombotic syndrome and recurrence of DVT.
Prognosis:
If Deep Vein Thrombosis is promptly and adequately treated, the prognosis is usually good, however, there is still a risk of recurrence.
