lecture 3

Question 1

What are the two most common types of venous thromboembolism (VTE)?

Answer 1

Deep vein thrombosis (DVT) and pulmonary embolism (PE).

Question 2

How does a pulmonary embolism (PE) occur?

Answer 2

A blood clot breaks loose (embolises) and travels to the pulmonary circulation, blocking blood flow.

Question 3

What are the components of Virchow’s Triad, summarising VTE pathophysiology?

Answer 3

Venous stasis, endothelial injury, and hypercoagulability.

Question 4

What are the long-term complications of VTE?

Answer 4

Post-thrombotic syndrome (PTS) and chronic thromboembolic pulmonary hypertension (CTEPH).

Question 5

Name three common risk factors for VTE.

Answer 5

Obesity, hospitalisation, and surgery with general anaesthesia lasting >90 minutes.

Question 6

How does increasing age affect VTE incidence?

Answer 6

The incidence rises significantly, reaching ~1/100 in patients over 80 years old.

Question 7

What are the classic signs and symptoms of DVT?

Answer 7

Leg pain, swelling, tenderness, discolouration, and pitting oedema.

Question 8

What are the common symptoms of a pulmonary embolism?

Answer 8

Shortness of breath, chest pain, haemoptysis, tachycardia, and hypotension.

Question 9

What are some atypical presentations of VTE?

Answer 9

Bilateral leg swelling, asymptomatic clots (e.g., found on cancer staging CT), or VTE at unusual sites (e.g., cerebral veins).

Question 10

What are the key aims of clinical and laboratory assessment in suspected VTE?

Answer 10

To confirm the presence of VTE, identify the underlying cause, assess contraindications to anticoagulation, and address other clinical considerations.

Question 11

Which clinical scoring system is commonly used to assess DVT risk?

Answer 11

The two-level DVT Wells score

Question 12

What is the significance of a Wells score ≥2 for DVT?

Answer 12

It indicates that DVT is likely, warranting further investigation.

Question 13

What is the initial confirmatory test for DVT diagnosis?

Answer 13

Proximal leg vein ultrasound

Question 14

When is a D-dimer test useful in suspected DVT?

Answer 14

To rule out DVT in patients with a low Wells score and no other risks.

Question 15

What are potential causes of elevated D-dimer levels aside from VTE?

Answer 15

Infection, inflammation, malignancy, pregnancy, and recent surgery.

Question 16

What imaging is used to confirm pulmonary embolism?

Answer 16

CT pulmonary angiography (CTPA) or ventilation-perfusion (V/Q) scan.

Question 17

How does heparin work as an anticoagulant?

Answer 17

It enhances antithrombin’s inhibition of clotting factors, particularly factor IIa (thrombin) and Xa.

Question 18

What is the mechanism of action of warfarin?

Answer 18

It inhibits vitamin K epoxide reductase, reducing the synthesis of clotting factors II, VII, IX, and X.

Question 19

Name two advantages of direct oral anticoagulants (DOACs) over warfarin.

Answer 19

Fixed dosing with no routine monitoring and lower risk of intracranial bleeding.

Question 20

Why is low molecular weight heparin (LMWH) preferred during pregnancy?

Answer 20

It does not cross the placenta and is safer for the fetus.

Question 21

How is warfarin’s anticoagulant effect monitored?

Answer 21

Using the international normalised ratio (INR).

Question 22

What is the standard duration of anticoagulation for provoked VTE?

Answer 22

Three months.

Question 23

When might indefinite anticoagulation be considered for VTE?

Answer 23

For unprovoked VTE or when persistent significant risk factors (e.g., cancer) are present

Question 24

What anticoagulants are first-line for VTE treatment?

Answer 24

Direct oral anticoagulants (DOACs), such as rivaroxaban or apixaban.

Question 25

Why is long-term anticoagulation not always initiated immediately after acute VTE?

Answer 25

The decision depends on the balance of recurrence risk off anticoagulation versus bleeding risk on anticoagulation.

Question 26

What is the first step in reducing the risk of hospital-acquired VTE?

Answer 26

Conducting a VTE risk assessment for all admitted patients.

Question 27

When should LMWH thromboprophylaxis be started for hospitalised patients?

Answer 27

Within 14 hours of admission if the VTE risk outweighs the bleeding risk

Question 28

Name two mechanical methods to prevent hospital-acquired VTE

Answer 28

Anti-embolic stockings and intermittent pneumatic compression devices.

Question 29

What lifestyle measures can help reduce VTE risk during hospitalisation?

Answer 29

Encouraging hydration and early mobilisation.

Question 30

What is the role of patient education in preventing VTE after hospital discharge?

Answer 30

Patients should be informed about ongoing VTE risk and provided with instructions on thromboprophylaxis if needed.