Pulmonary Embolism

Question 1

Where do most PEs arise from. (2)

Answer 1

Usually arise from a venous thrombosis in the pelvis or legs.

Question 2

What is a PE. (2)

Answer 2

A clot that breaks off from another part of the body (eg legs).
It passes through the right side of the heart before lodging in the pulmonary circulation.

Question 3

What are some rare causes of PE. (7)

Answer 3

Right ventricular thrombus (post-MI). 
Septic emboli (right sided endocarditis). 
Fat. 
Air. 
Amniotic fluid embolism. 
Neoplastic cells. 
Parasites.

Question 4

What are the risk factors for PEs. (8

Answer 4

Recent surgery (especially abdominal, pelvic or hip/knee replacement). 
Thrombophilia(eg antiphospholipid syndrome). 
Leg fracture. 
Prolongued bed rest/reduced mobility. 
Malignancy. 
Pregnancy/post partum.
Pill/HRT.
Previous PE.

Question 5

What are the symptoms of PEs. (5)

Answer 5

Acute breathlessness. 
Pleuritic chest pain. 
Haemoptysis. 
Dizziness. 
Syncope.

Question 6

What should you ask when taking a history of a patient with a PE. (3)

Answer 6

PMH.
FH of thromboembolism.
Risk factors.

Question 7

What are the clinical signs of PEs. (13)

Answer 7

Pyrexia. 
Cyanosis. 
Tachypnoea. 
Tachycardia. 
Hypotension. 
Gallop rhythm. 
Loud P2. 
R ventricular heave. 
AF. 
Raised JVP. 
Pleural rub. 
Pleural effusion. 
Signs of cause (eg DVT).

Question 8

What tests should be done in a patient suspected of a PE. (6

Answer 8

FBC, UandE baseline, clotting screen, D-dimer. 
ABG may show low O2 and low CO2. 
CXR. 
CTPA. 
ECG.

Question 9

What may be seen on the CXR of a patient with a PE. (7)

Answer 9

May be normal. 
May show oligaemia of affected segment. 
Dilated pulmonary artery. 
Linear atelectasis. 
Small pleural effusion. 
Wedge-shaped opacities. 
Cavitation.

Question 10

What is the treatment for PE. (3)

Answer 10

Anticoagulate with LMWH. Start warfarin. Stop heparin when INR >2 and continue warfarin therapy for a minimum of 3 months (aim for INR 2-3).
Thrombolysis for a massive PE.
Consider placement of a vena caval filter in patients who develop emboli despite adequate anticoagulation.

Question 11

How can you prevent PEs. (5)

Answer 11

Give heparin to all immobile patients. 
Prescribe compression stockings.
Encourage early mobilization. 
Stop HRT and the Pill pre op. 
If FH or PMH of thromboembolism, consider investigations for thrombophilia.

Question 12

Who should you perform D dimers in.

Answer 12

Only in patients without a high probability of PE.

A negative D dimer excludes PE, a positive test does not confirm PE and imaging is required.

Question 13

What is the first line imaging for a suspected PE.

Answer 13

CTPA.

Question 14

A patient suddenly collapses a week after abdominal surgery.

Answer 14

PE.

Always suspect PE in a patient who suddenly collapses 1-2weeks after surgery.

Question 15

What is the mortality rate for PE in England.

Answer 15

30,000-40,000/year.

Question 16

What may be seen on the ECG of a patient with a PE. (3)

Answer 16

S1Q3T3 (deep s waves in I, Q waves in III, inverted T waves in III).
RBBB.
R axis deviation.