Deep Vein Thrombosis

Predispositions

General   Age - over 40 Malignancy Dehydration Immobility Previous thrombotic event Oral Contraceptive Pill (OCP) Surgery - especially if longer than 30 minutes, or lower limb surgery Haematological   Factor V Leiden Protein S & C deficiency Homocystinaemia Lupus anticoagulant Antithrombin III deficiency

Clinical Features

May be asymptomatic Calf tenderness Calf oedema Calf erythema Calf warmth

Investigations

Diagnostic   U/S - calf Aetiology   FBE   Polycythaemia Thrombocythaemia Coagulation studies   INR - factor V & fibrinogen deficiency APTT - factor V, VIII & fibrinogen deficiency Factor V Leiden point mutation Homocystinaemia Protein C deficiency Protein S deficiency Antithrombin III deficiency Lupus anticoagulant

Prevention

Warfarin prophylaxis Preoperative heparin Adequate fluid maintenance TED Pressure Stockings Calf stimulators Early mobilisation

Treatment

Heparin   1 week INR of 2.0 Simultaneous warfarin   3 - 6 months INR of 2.0 - 4.5, depending on risk factors