Pulmonary Embolism

Question 1

Describe the pathophysiology of a pulmonary emoblism

Answer 1

Thrombus forms in the valves of veins, usually the deep veins of the legs due to low pressure and slow flow

Clot breaks off, travels up the IVC and iliac vein, entering the heart at the right atrium

Thrombus then embolises/wedges in the pulmonary arteries of the lung, blocking blood flow

Question 2

What are the causes/risk factors of a pulmonary embolism?

Answer 2

Trauma

Recent surgery

Malignancy

Pregnancy

Thrombophilia

• Factor 5 Leiden

Immobility

Air travel

Oral oestrogens

Question 3

Describe the presentation of pulmonary embolism

Answer 3

Pleuritic chest pain

Haemoptysis

Isolated acute dyspnoea

Syncope: Large thrombus

Raised JVP

Cough

Vitals

• Hypoxic
• Pyrexia
• Tachycardia
• Hypotension

Auscultation

• Pleural rub
• Pulmonary oedema

Question 4

What investigations are used in the diagnosis of a pulmonary embolism?

Answer 4

CTPA

D-Dimer

Ventilation/Perfusion Scan

ECG: Tachycardia

Thrombophilia testing

ABG

Doppler US of leg: Check for DVT

ECHO: Used if massive central PE

Question 5

What is the management of pulmonary embolism?

Answer 5

Oxygen

Analgesia

Anti-coagulation

• DOAC that can be continued once diagnosis is confirmed
• LMWH if severe renal impairment or malignancy

Thrombolysis

• Only in massive PE with haemodynamic compromise

Inferior vena cava filters

• Considered for patients with recurring PE despite adequate anticoagulation

Pulmonary Embolectomy

Question 6

How can pulmonary embolisms be prevented?

Answer 6

Early mobilisation

Anti-embolisation stockings

Question 7

What score is used to determine the probability of a patient having a pulmonary embolism?

Answer 7

Wells/Geneva Score

Question 8

What is the diagnostic investigation for pulmonary embolism?

Answer 8

computed tomography pulmonary angiogram (CTPA)

Question 9

What is the first line investigation if Wells score is >4?

Answer 9

CTPA

Question 10

What is the first line investigation if Wells score <4?

Answer 10

D Dimer

Question 11

When is a V/Q scan used over a CTPA?

Answer 11

If patient has contrast allergy

If renal impairment as contrast is nephrotoxic

Question 12

What are features of the Wells score?

Answer 12

Clinical signs and symptoms of DVT

• 3 points

An alternative diagnosis is less likely than PE

• 3 points

HR >100

• 1.5 points

Immobilisation for more than 3 days or surgery in pervious 4 weeks

• 1.5 points

Previous DVT/PE

• 1.5 points

Haemoptysis

• 1 point

Malignancy in past 6 months

• 1 point

Question 13

What score identifies PE patients that can be managed as outpatients?

Answer 13

Pulmonary Embolism Severity Index Score (PESI)

Question 14

How long should PE patients be anticoagulated for?

Answer 14

All patients at least 3 months

3-6 months for patients with active cancer

>6 months for unprovoked PE (no obvious precipitating event)

Question 15

What investigation is used if CTPA is negative?

Answer 15

Doppler US to rule out DVT