Pulmonary Embolism

Question 1

Define Pulmonary Embolism?

Answer 1

Occlusion of pulmonary vessels, most commonly by a thrombus that has travelled to the pulmonary vascular system from another site

Question 2

What is the aetiology of Pulmonary Embolism?

Answer 2

Thrombus
95% arise from DVT in the lower limbs
Rarely arises in the right atrium (in AF patients)

Question 3

What are some other causes of embolus?

Answer 3

Amniotic Fluid 
Air 
Fat 
Tumour 
Mycotic

Question 4

What are the risk factors for PE?

Answer 4

Surgical patients 
Immobility 
Obesity 
OCP
Heart Failure 
Malignancy

Question 5

What is the epidemiology of Pulmonary Embolism?

Answer 5

Relatively common (especially in hospitalised patients)
Occur in 10-20% of patients with confirmed proximal DVT

Question 6

What does the presenting symptoms of Pulmonary Embolism depend on?

Answer 6

Site and Size of the embolus

Question 7

What are the presenting symptoms of a small Pulmonary Embolism?

Answer 7

May be asymptomatic

Question 8

What are the presenting symptoms of a moderate Pulmonary Embolism?

Answer 8

Sudden-onset SOB
Cough
Haemoptysis
Pleuritic Chest Pain

Question 9

What are the presenting symptoms of a large (or proximal) Pulmonary Embolism?

Answer 9

Same as moderate and:
Severe central pleuritic chest pain
Shock
Collapse 
Acute Right Heart Failure
Sudden Death

Question 10

What are the presenting symptoms of Multiple Small Recurrent Pulmonary Embolisms?

Answer 10

Symptoms of pulmonary hypertension

Question 11

How can the severity of a Pulmonary Embolism be assessed?

Answer 11

Based on associated signs

Question 12

What are the signs of a small Pulmonary Embolism on physical examination?

Answer 12

Often no clinical signs

There may be some tachycardia and tachypnoea

Question 13

What are the signs of a moderate Pulmonary Embolism on physical examination?

Answer 13

Tachypnoea
Tachycardia
Pleural rub
Low O2 saturation (despite O2 supplementation)

Question 14

What are the signs of a massive Pulmonary Embolism on physical examinaton?

Answer 14

Shock
Cyanosis
Signs of right heart strain

Question 15

What are the signs of right heart strain?

Answer 15

Raised JVP
Left parasternal heave
Accentuated S2 heart sound

Question 16

What are the signs of Multiple Recurrent Pulmonary Embolism on physical examination?

Answer 16

Signs of pulmonary hypertension

Signs of RH failure

Question 17

How do you determine the best investigation for Pulmonary Embolism?

Answer 17

Well’s Score

Question 18

How is the Well’s Score used?

Answer 18

Low Probability (Wells 4 or less) - Use D-Dimer
High Probability (Wells > 4) - required imaging (CTPA)

Question 19

What bloods would you do for a Pulmonary Embolism?

Answer 19

ABG

Thrombophilia screen

Question 20

What might you see on an ECG in Pulmonary Embolism?

Answer 20

May be normal
May show tachycardia, right axis deviation or RBBB
May show S1Q3T3 pattern

Question 21

Why do we do a CXR for Pulmonary Embolism?

Answer 21

Often normal but helps exclude other diagnoses

Question 22

How do we use Spiral CT Pulmonary Angiogram in Pulmonary Embolism?

Answer 22

First Line Investigation
Poor sensitivity for small emboli
Very sensitive for medium to large emboli

Question 23

How do we use Ventilation-Perfusion (VQ) scan in Pulmonary Embolism?

Answer 23

Identifies areas of ventilation and perfusion mismatch which would indicate an area of infarcted lung

Question 24

Why do we not use Pulmonary Angiogram for Pulmonary Embolism?

Answer 24

Invasive

Rarely necessary

Question 25

Why do we use Doppler US of Lower Limb in Pulmonary Embolism?

Answer 25

Allows assessment of venous thromboembolism

Question 26

What might you see on Echocardiography on Pulmonary Embolism?

Answer 26

May show right heart strain

Question 27

What is the primary prevention of Pulmonary Embolism?

Answer 27

Compression Stockings Heparin prophylaxis for those at risk Good mobilisation and adequate hydration

Question 28

What do we do if a patient with Pulmonary Embolism is haemodynamically stable?

Answer 28

``` O2 Anticoagulation with heparin or LMWH Switch over to oral warfarin for at least 3 months Maintain INR 2-3 Analgesia ```

Question 29

What do we do if a patient with Pulmonary Embolism is haemodynamically unstable (massive PE)?

Answer 29

Resuscitate O2 IV fluids Thrombolysis with tPA may be considered if cardiac arrest is imminent

Question 30

What is the surgical and radiological management of Pulmonary Embolism?

Answer 30

Embolectomy IVC filters - sometimes used for recurrent PEs despite adequate anticoagulation or when anticoagulation is contraindicated

Question 31

What are the possible complications of Pulmonary Embolism?

Answer 31

Death Pulmonary Infarction Pulmonary Hypertension Right Heart Failure

Question 32

What is the prognosis for patients with Pulmonary Embolism?

Answer 32

30% mortality in those left untreated 8% mortality with treatment Increased risk of future thromboembolic disease