Pulmonary Embolism (PE)

🔍 When to Suspect

Sudden-onset shortness of breath and/or pleuritic chest pain, especially with risk factors for venous thromboembolism (VTE), haemoptysis, or signs of circulatory collapse

From the full topic in The Ocean Library: Pulmonary Embolism (PE)

🧭 When to suspect

Suspect a pulmonary embolism (PE) in anyone with sudden or recent:

• Breathlessness

• Pleuritic chest pain

• Cough

• Haemoptysis

The presentation ranges from mild breathlessness to cardiovascular collapse (faintness, syncope, shock), and the diagnosis is frequently missed because a well-looking patient with normal observations can still have a PE.

PE is almost always a complication of underlying venous thromboembolism (VTE), usually a clot embolising from a deep vein thrombosis (DVT). A high index of suspicion is essential when risk factors are present:

• Recent surgery or significant immobility

• Active cancer

• Previous VTE

• Pregnancy or the puerperium

• Combined hormonal contraception or hormone replacement therapy

Estimate clinical probability and direct the pathway accordingly. Use the two-level PE Wells score:

• A likely score (more than 4 points) points to immediate imaging

• An unlikely score (4 points or less) is followed by a D-dimer

Most patients with suspected PE are referred for same-day assessment, but the GP stratifies risk, starts interim anticoagulation when testing is delayed, and must never miss a massive PE.

Two-level PE Wells score – clinical feature	Points
Clinical signs and symptoms of DVT (leg swelling and pain on palpation of the deep veins)	3
An alternative diagnosis is less likely than PE	3
Heart rate more than 100 beats per minute	1.5
Immobilisation for more than 3 days, or surgery in the previous 4 weeks	1.5
Previous DVT or PE	1.5
Haemoptysis	1
Malignancy (on treatment, treated in the last 6 months, or palliative)	1
PE likely → arrange CT pulmonary angiogram (CTPA)	> 4
PE unlikely → arrange D-dimer	≤ 4

Where overall clinical suspicion is low (gestalt risk under about 15% and other diagnoses are feasible), the PE rule-out criteria (PERC) can be used to decide whether any further PE testing is needed at all.

Source: NICE NG158

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