Pulmonary Embolism

Question 1

What do PEs usually rise from?

Answer 1

venous thrombosis in the pelvis or legs

Question 2

What is the mechanism of a PE

Answer 2

Clots break off and pass-through veins and the right side of the heart before lodging in the pulmonary circulation

Question 3

What are the rare causes of PE?

Answer 3

o	RV thrombus (post-MI)
o	Septic emboli (right-sided endocarditis)
o	Fat, air or amniotic fluid embolism
o	Neoplastic cells
o	Parasites

Question 4

What are the main risk factors for a PE?

Answer 4

• Recent surgery, especially abdominal/pelvic or help/knee replacement
• Thrombophilia e.g., antiphospholipid syndrome
• Leg fracture
• Prolonged bed rest/ reduced mobility
• Active inflammation (infection, IBD)
• Malignancy, myeloproliferative disorder
• Pregnancy/post-partum, combined oral contraceptive pill, HRT
• Previous PE

Question 5

What are the main symptoms of a PE?

Answer 5

• Acute dyspnoea
• Pleuritic chest pain
• Haemoptysis
• Syncope

Question 6

What are the main signs of a PE?

Answer 6

• Pyrexia
• Cyanosis
• Tachypnoea
• Tachycardia
• Hypotension
• Raised JVP
• Pleural rub
• Pleural effusion
• Gallop rhythm
• Loud P2
• Right ventricular heave
• AF

Question 7

What are the main investigations and tests that should be carried out if a PE is suspected?

Answer 7

• FBC, U&E, baseline clotting, D-dimers
• ABG
• CXR
• ECG
• Serum D-dimer

Question 8

What is an ABG in a PE likely to show?

Answer 8

o Hyperventilation and poor gas exchange

o decreased PaO2 and decreased PaCO2, increased pH

Question 9

What would an abnormal chest x-ray in a PE show?

Answer 9

o Show oligemia of affected segment, dilated pulmonary artery, linear atelectasis, small pleural effusion, wedge-shaped opacities OR cavitation (rare)

Question 10

What can an ECG show in a PE?

Answer 10

o Normal OR
o Tachycardia, RBBB, right ventricular strain (inverted T in V1-4)
o Classical SI QIII TIII pattern = RARE

Question 11

What instances can a D-dimer value be increased?

Answer 11

thrombosis, inflammation, post-op, infection, malignancy

Question 12

What scoring system should be used to investigate a PE?

Answer 12

Wells Score

Question 13

What are the features of the Wells Scoring system?

Answer 13

Clinical signs and symptoms of DVT (leg pain and pain on deep palpation of veins)
Heart Rate >100 bpm
Recently bed-ridden (>3days) or major surgery (<4 weeks)
Previous DVT or PE
Haemoptysis
Cancer receiving active treatment, treated in last 6/12, palliative
An alternative diagnosis is less likely than PE