Deep vein thrombosis (DVT) [Complete]

Question 1

Define DVT

Answer 1

Refers to the intra-luminal occlusion of any vein within the deep system of a limb (either arm or leg) or the pelvis.

Question 2

What are the main risk factors for DVT? (11)

Answer 2

Age > 60

Dehydration

Active cancer

Recent long distance travel

Recent orthapaedic or pelvic surgery

Past history of VTE

Family history of VTE

Obesity

Thrombophillia

Pregnancy

Combined oral contraceptive pill

Question 3

What are the main clinical features of a DVT? (4)

Answer 3

Unilateral, swolen, warm calf

Tenderness on palpation of deep veins

Distension of superficial veins

Pitting oedema

Question 4

What scoring system should be used if a patient is suspected of having a DVT?

Answer 4

Two-level DVT Wells score

Question 5

DVT is likely if there is a Well’s score of?

Answer 5

2 or more

Question 6

What investigations should be performed if a patient has a Well’s score of 2 or more?

Answer 6

Proximal leg vein ultrasound scan within 4 hours: If positive a diagnosis of DVT is made.

If ultrasound is negative, arrange a D-dimer test: If both are negative, DVT can be excluded.

D-dimer test if ultrasound cannot be arranged within 4 hours AND THEN interim therapeutic anticoagulation (e.g. DOAC). Should have the scan within 24 hours.

Question 7

What investigation, if positive, is diagnostic for DVT?

Answer 7

Proximal leg vein ultrasound scan

Question 8

For a patient suspected of having DVT, if a proximal leg vein ultrasound cannot be arranged within 4 hours, what is the next best alternative action?

Answer 8

D-dimer test AND interim therapeutic anticoagulation (usually DOAC)

Question 9

If a patient has negative findings on a proximal ultrasound scan for DVT, can it therefore be excluded?

Answer 9

Cannot be excluded. Patient should be tested for D-dimer to completely rule out DVT

Question 10

If a proximal leg ven ultrasound scan is negative for DVT however D-dimer is positive, What course of action should be taken?

Answer 10

Stop interim therapeutic anticoagulation

Offer a repeat proximal leg vein ultrasound scan 6 to 8 days later

Question 11

What investigations should be performed if a patient has a Well’s score of 1 or less? (DVT unlikely).

Answer 11

Perform a D-dimer test within 4 hours

If a D-dimer test result cannot be given within 4 hours, provide interim therapeutic anticoagulation.

Question 12

A patient has a Well’s score of 0 (DVT unlikely) however their D-dimer test is positive. What course of action should be taken?

Answer 12

Arrange for a proximal leg vein ultrasound scan wihtin 4 hours.

Provide interim therapeutic anticoagulation if scan cannot be arranged within 4 hours (ideally should be within 24 hours)

Question 13

Name 2 examples of DOACs used in the management of DVT

Answer 13

Apixaban

Rivaroxaban

Question 14

What is the management plan for a patient diagnosed with DVT?

Answer 14

Pharmacological:

Provide DOACs (e.g. apixaban, rivaroxaban)

Take for at least 3 months if provoked DVT ) [3-6 months for patients with active cancer]

Take for up to 6 months if unprovoked DVT

Surgical:

Inferior vena cava filters (if anticoagulation is contraindicted)

Question 15

What are some complications involved with taking DOACs in treatment of DVT?

Answer 15

Low bleeding risk

Question 16

What are some contraindictions for DOACs? (3)

Answer 16

High bleeding risk patients:

E.g. bleeding disorders, severe hepatic failure (due to lack of coagulant proteins), active bleeding

Question 17

What are some complication of DVT? (4)

Answer 17

Pulmonary embolism

Venous insufficiency (blood pooling within legs as it cant return to the heart)

Recurrent DVT

Post-thrombotic syndrome (pain, swelling, hyperpigmentation, dermatitis, ulcers, gangrene and lipodermatosclerosis caused by chronic venous hypertension.)

Question 18

What is a provoked VTE?

What is an unprovoked VTE?

Answer 18

Provoked VTE: due to an obvious precipitating event e.g. immobilisation following major surgery.

Unprovoked VTE: occurs in the absence of an obvious precipitating event, i.e. there is a possibility that there are unknown factors (e.g. mild thrombophilia) making the patient more at risk from further clots