DVT

Question 1

define DVT?

Answer 1

• A DVT is a formation of a thrombus within the deep veins (most commonly in the calf or thigh)

Question 2

what is the aetiology of DVT?

Answer 2

• Deep veins in the legs are more prone toblood stasis, hence clots are more likely to form.
• Virchows triad contributes towards blood clots = hypercoagulability of blood, vessel wall injury, stasis of blood

Question 3

what are the risk factors of a DVT?

Answer 3

o	COCP
o	Post-surgery
o	Prolonged immobility
o	Obesity
o	Pregnancy
o	Dehydration
o	Smoking
o	Polycythaemia
o	Thrombophilia (e.g. protein C deficiency)
o      Malignancy

Question 4

what is the epidemiology of DVT?

Answer 4

• DVTs are very common

- especially in hospitalized patients

Question 5

what are the presenting symptoms of DVTs?

Answer 5

• very swollen limb

- / sometimes painless

Question 6

what are the signs of a DVT on examination?

Answer 6

• local erythema, warmth, swelling
• large leg circumference
• varicosities (swollen vessels)
• skin color changes

Question 7

what needs to be examined when looking for a PE

Answer 7

• resp rate
• pulse oximetry
• pulse rate

Question 8

what are appropriate investigations for DVT?

Answer 8

• 1. Doppler ultrasound
     this detects the flow of blood through your vessels

-2. impedance Plethysmography
this is detecting changes in electrical resistance due to the changes in blood volume

-3. Bloods
D-dimer - this is used as a negative predictor

• 4.Thrombophilia screen if indicated
• 5. If PE is suspected check ECG, CXR and ABG

Question 9

what is a management plan of anticoagulation for DVT?

Answer 9

1. Anticoagulation
   - Heparin whilst waiting for warfarin
   - DVTs extending above the knee need anti coag for 6 months
   - DVTs that don’t extend above the knee need anti coag for 3 months
   - recurrent DVTs need long term warfarin

Question 10

what are other general management steps for DVTs?

Answer 10

• IVC filter
• prevention methods such as graduated compression socks
• mobilisation
• prophylactic heparin

Question 11

what are the possible complications of DVT?

Answer 11

• PE
• Venous Infarction
• Thrombophlebitis
• Chronic venous insufficiency

Question 12

what is the prognosis for patients with DVT?

Answer 12

• depends on the extent of the DVT
• below knee DVTs have a good prognosis
• proximal DVTs have a greater chance of embolism