Deep vein thrombosis

Question 1

What is the definition of a DVT?

Answer 1

A thrombus occurring in the deep vein of your leg

Question 2

What is the epidemiology of a DVT?

Answer 2

1 in 1000 people per year suffer

Question 3

What is the pathology of DVT’s?

Answer 3

• Most form just above and behind a venous valve
• 3 factors (Virchow’s triad): venous stasis, activation of blood coagulation, vein damage
• May travel to the lungs and cause a PE

Question 4

What are the risk factors for DVT’s?

Answer 4

• Surgery
• Prostactectomy
• Trauma
• Immobility
• Prior history of DVT/CVA
• Age - >60
• Obesity
• Hypertension
• Prolonged travel
• Cancer
• Varicose veins
• Heart failure
• AF
• Thrombophilia
• Pregnancy
• OCP/HRT
• Smoking

Question 5

What are the signs/symptoms of DVT?

Answer 5

• Limb pain/tenderness along the line of the deep veins
• Swelling, redness and pain of the calf/thigh – usually unilateral
• Pitting oedema
• Distention of superficial veins
• ↑ skin temperature
• Skin discolouration – erythema/purple/cyanosed
• Homan’s sign – pain in calf upon dorsiflexion of foot is often present but not diagnostic
• PE symptoms
• Venous eczema – long term due to damage of venous valves
• Swollen limb – long term due to damage of venous valves
• Oedema – long term due to damage of venous valves

Question 6

What other diseases present similarly to DVT?

Answer 6

• Cellulitis
• Thrombophlebitits
• Heart failure
• Cirrhosis
• Nephrotic syndrome
• Venous/lymphatic obstruction
• Congenital vascular abnormalities
• Vasculitis
• Septic arthritis
• Compartment syndrome
• Ruptured Baker’s cyst

Question 7

What investigations are carried out for suspected DVT?

Answer 7

• Vascular examinations – inc. doppler
• DVT Well’s score
• US
• D-dimer
• CT contrast venography
• MRI contrast venography
• Fibrinogen scanning
• Impedance plethysmography – measures changes in electrical resistance of the calf which reflects blood volume changes
• Bloods (FBC, serum calcium, LFTs)
• Urinalysis
• CXR

Question 8

What are the surgical treatments for DVT?

Answer 8

• Inferior vena caval filters
• Balloon pulmonary angioplasty
• Leg amputation – extreme cases

Question 9

What are the pharmacological treatments for DVT?

Answer 9

• Anticoagulant – LMWH/fondaparinux, Warfarin, NOACs

Question 10

What are the non pharmacological treatments for DVT?

Answer 10

• Compression stockings – reduces risk of occurrence
• Weight loss
• Smoking cessation