Pulmonary embolism

Question 1

Risk factors

Answer 1

Immobility

Recent surgery

Long haul flights

Pregnancy

Hormone therapy with oestrogen

Malignancy

Polycythaemia

SLE

Thrombophilia

Question 2

VTE prophylaxis

Answer 2

Any patient at increased risk of VTE

LMWH

ANti-embolic stockings

Question 3

LMWH example

Answer 3

Enoxaparin

Question 4

Contraindication to LMWH

Answer 4

Active bleeding

Existing anticoagulation with warfarin or a NOAC

Question 5

Contraindication for compression stockings

Answer 5

Peripheral artery disease

Question 6

Presentation

Answer 6

SOB

Cough (+/- haemoptysis)

Pleuritic chest pain

Hypoxia

Tachycardia

Raised RR

Low grade fever

Haemodynamic instability

Question 7

Wells score

Answer 7

Predicts the risk of a patient presenting with symptoms actually having a DVT or PE

If likely perform CTPA

If unlikely perform d-dimer then if positive CTPA

Question 8

Main options to establish definitive diagnosis

Answer 8

CTPA

VQ scan

Question 9

CTPA

Answer 9

First line choice

More readily available

Gives information about alternatives such as pneumonia or malignancy

Question 10

VQ scan

Answer 10

Used in patients with renal impairment, contrast allergy or at risk from radiation where a CTPA is unsuitable

Question 11

ECG findings

Answer 11

Large S waves in lead 1

Large Q wave in lead 3

Inverted T wave in lead 3

(S1Q3T3)

RBBB and RAD

Sinus tachycardia

Question 12

Chest xray

Answer 12

Recommended for all patients to exclude other pathology

Typically normal in PE

Possible wedge shaped opacification

Question 13

VQ scan findings

Answer 13

Sensitivity around 75% and specificity 97%

Deficit in perfusion as thrombus blocks blood flow

Lung tissue will be ventilated but not perfused

Question 14

Other causes of VQ mismatch

Answer 14

PE

AV malformations

Vasculitis

Previous radiotherapy