Deep Vein Thrombosis + PE

Question 1

What causes a DVT to form?

Answer 1

Stasis in the deep veins and/or hypercoagubility

Question 2

What are the risk factors for DVT/VTE?

Answer 2

Aging - Tissue Trauma - Immobility - Obesity - Smoking - Pregnancy - Exogenous Oestrogen (e.g. the pill) - Inherited Thrombophilia - Some systemic diseases like cancer

Question 3

What are the symptoms of a DVT?

Answer 3

Persistent discomfort & calf tenderness
Warmth
Erythema (redness)
Unilateral Limb Swelling

Question 4

How do we investigate a suspected DVT?

Answer 4

With a clinical probability assessment such as the wells score
Also a D Dimer as it would rule out thrombus
Compression Ultrasound will confirm, locate and assess severity of a DVT

Question 5

How is a DVT treated?

Answer 5

Compression Stockings to encourage flow and anti-coagulant LMWH.
Thrombolysis & thrombectomy are also possible but considered too high risk in most cases

Question 6

Where do VTEs most often lodge?

Answer 6

In the pulmonary arteries making them Pulmonary Emboli

Question 7

What are the symptoms of a normal PE?

Answer 7

Pleuritic chest Pain
Dyspnoea
Haemoptysis
Tachycardia
And a pleural rub on auscultation

Question 8

What other symptoms come with a massive PE?

Answer 8

Collapse
cyanosis
Sudden Death
Low BP
raised JVP
Altered heart sounds

Question 9

How do we investigate a suspected PE?

Answer 9

• Clinical probability assessment (wells score)
• D dimer to rule out PE
• FBC and clotting status to rule out some important secondary causes for the VTE
• CT Pulmonary Angiogram - The first line in imaging
• Isotope VQ scan to locate PE
• ECG
• Arterial Blood Gasses

Question 10

How do we treat a PE?

Answer 10

Short Term LMWH (5 days)
Oral Anticoagulant - Warfarin (3 months)
Thrombolysis for a massive PE
Thrombectomy is possible but not used much these days
Vena Caval Filter - Traps emboli before entering heart, controversial af

Question 11

When would we keep the LMWH and not use warfarin in a PE case?

Answer 11

If the patient is pregnant
As Warfarin is teratogenic in the 1st trimester

Question 12

How do we actively prevent VTEs in some hospital patients?

Answer 12

Early mobilisation
Regular Movement
Anti-embolism compression stockings
Daily LMWH injections

Question 13

What makes up a Venous thrombus?

Answer 13

Fibrin and RBCs. Hence its called a ‘red thrombus’

Question 14

What makes up an arterial thrombus?

Answer 14

Fibrin and platelets. Hence they’re called ‘white thrombi’

Question 15

What typically causes venous thrombi?

Answer 15

Hypercoagubility - Pregnancy or Trauma
And Stasis - Travel or bed-bound.

Question 16

What is the most common form of inherited thrombophilia?

Answer 16

Factor V Leiden.
It affects 5% of caucasians, increasing risk of VTE of 5 times.

Question 17

What is caused by a long-term DVT?

Answer 17

Post-Phlebitic Syndrome:
- Inflammation, valvular incompetance & oedema due to a DVT.
Swelling - Discomfort - brown/red discolouration - Ulceration - Varicose Veins

Question 18

What are the parts of the wells score for a clinical probability assessment?

Answer 18

+1:
Active Cancer - Tender Veins - Whole leg swelling - Bed>3 days/Surgery within 4 weeks - Calf Swelling>3cm - Pitting oedema - Collateral Veins - Paralysis/plaster

-2:
Other Diagnosis Likely

Question 19

How do anti-embolism stocking work? (graduated Compression stockings)

Answer 19

Apply a greater pressure at the ankle than the calf and even less at thigh pushing blood through the veins. acieves a venous blood velocity 140% of the baseline

Question 20

What do we use graduated compression stockings for?

Answer 20

Preventing VTE
Chronic Venous Insufficiency
Varicose Veins
Oedema
Lymphoedema
Preventing post-phlebitic syndrome

Question 21

What is a possible complication of long term PE?

Answer 21

Pulmonary Hypertension