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Pulmonary embolism
Think of it, score it, image it — and treat the unstable patient first. PE hides behind vague breathlessness and chest pain. Use clinical probability to decide between D-dimer and CTPA, start anticoagulation early when it's likely, and recognise the massive PE that needs thrombolysis. Built for revision, not live patient decisions.
Settle them, and check the basics
stable or not?Red flags — what each should make you think
A normal CXR in a hypoxic, tachycardic patient should make you think of PE. And a sinus tachycardia that won't settle is often the only sign. The ECG may show S1Q3T3, but sinus tachycardia is far more common.
If PE is suspected
- O₂Oxygen to target
- ECGECG + monitor
- WTwo-level Wells score
- AcStart anticoagulation
- 🫀If shocked: bedside echo
- ☎Senior early
Understand the patient — the diagnostic pathway
NICE NG158Two-level Wells score
- Clinical signs of DVT — 3
- PE the most likely diagnosis — 3
- HR above 100 — 1.5
- Immobilised 3+ days or surgery in last 4 weeks — 1.5
- Previous DVT/PE — 1.5
- Haemoptysis — 1
- Active cancer (treatment within 6 months or palliative) — 1
Above 4 (PE likely) → CTPA immediately (or interim anticoagulation if delayed). 4 or less (PE unlikely) → D-dimer; if positive → CTPA. If clinical suspicion is low, consider PERC: if all criteria are negative (age under 50, HR under 100, SpO₂ ≥95%, no haemoptysis, no oestrogen, no previous VTE, no unilateral leg swelling, no recent surgery/trauma), no further testing is needed.
Treatment (NICE)
- DOAC first-line — apixaban or rivaroxaban (also an option in cancer-associated VTE); LMWH then dabigatran/edoxaban, or LMWH/warfarin as alternatives
- Severe renal impairment, APS, extremes of weight — needs tailored choice
- At least 3 months of anticoagulation; review provoked vs unprovoked
- Outpatient management for low-risk PE (sPESI 0 or Hestia negative) with good follow-up
Work A–E — assess and act as you go
The diagnoses you must not miss
tap to open eachWhat points toward it, what would rule it in, and how to manage it.
SBP below 90 for more than 15 min, or requiring vasopressors, or cardiac arrest.
CTPA if stable enough; otherwise bedside echo showing RV dilatation is enough to act.
Systemic thrombolysis (e.g. alteplase per local protocol) unless contraindicated; senior, ITU. Surgical or catheter-directed options if thrombolysis contraindicated. In arrest, thrombolyse and continue CPR for a prolonged period.
Normotensive but RV dysfunction on CT/echo and raised troponin.
CTPA, echo, troponin, BNP.
Anticoagulate (LMWH often preferred initially), monitor in HDU; rescue thrombolysis if deteriorates.
Tearing pain, pulse deficit, neuro signs.
CT aortogram.
No anticoagulation; BP/HR control; cardiothoracic/vascular.
Chest pain and breathlessness with ECG changes, raised JVP with muffled heart sounds, or absent breath sounds.
ECG, echo, CXR.
Treat the actual cause.
Investigate — what to order, when, and what it tells you
test with a question in mindD-dimer
CTPA
V/Q scan
Supportive
How the plan comes together
disposition · handoverambulatory
Low-risk PE (sPESI 0/Hestia negative), stable, good social support: DOAC, written information, follow-up arranged.
admit / HDU
Hypoxia, RV strain, raised troponin, haemodynamic instability, high bleeding risk, or other reasons to admit.
Hand over: Wells score, imaging, anticoagulant and time of first dose, risk class.
Unstable? Thrombolyse. Stable? Wells, then D-dimer or CTPA, and anticoagulate early if the scan will be delayed. Always pause to exclude dissection before anticoagulating. Nicely done getting here.
Clerking template
copy or downloadPulmonary embolism — documentation structure
A structure and prompt list to help you document and think systematically. It is not a completeness check and cannot guarantee nothing is missed — use your trust's own proforma, your seniors, and your clinical judgement.
Test yourself
active recallCover the answer, say it out loud, then reveal. Retrieval beats re-reading.
0 / 10 knownFrequently asked questions
quick answersWhat are the red flags for suspected pulmonary embolism (PE)?
- SBP below 90 for 15 min, or collapse — think massive (high-risk) PE
- Cardiac arrest, PEA — think PE — consider thrombolysis in arrest
- Raised troponin, RV dilatation — think intermediate-high risk PE
- Hypoxia with a clear chest — think PE until proven otherwise
- Tearing pain, unequal pulses — think aortic dissection — no anticoagulation
- Pregnant or postpartum — think different imaging pathway
What is the initial management of suspected pulmonary embolism (PE)?
- Oxygen to target — 94–98%
- ECG + monitor — tachycardia, right heart strain, exclude ACS
- Two-level Wells score — PE likely (above 4) vs unlikely (4 or less)
- Start anticoagulation — if CTPA will be delayed and PE is likely (unless contraindicated)
- If shocked: bedside echo — RV dilatation supports PE; senior for thrombolysis
- Senior early — massive or submassive PE
Always alongside senior support and your local guideline.
What diagnoses must you not miss in suspected pulmonary embolism (PE)?
- Massive (high-risk) PE — shock · arrest
- Intermediate-high risk PE — RV strain + troponin
- Aortic dissection (mimic) — don't anticoagulate
- ACS / tamponade / pneumothorax (mimics) — same symptoms, different fix
Open each one in the must-not-miss section for what points toward it, how to rule it in, and how to manage it.
What investigations should a junior doctor order for suspected pulmonary embolism (PE)?
- D-dimer — Negative = PE excluded; positive = needs imaging.
- CTPA — RV strain, alternative diagnoses.
- V/Q scan — Contrast allergy, renal impairment, pregnancy (with CXR first).
- Supportive — Risk stratification.
Admit or discharge: how is the plan decided for suspected pulmonary embolism (PE)?
- Ambulatory — Low-risk PE (sPESI 0/Hestia negative), stable, good social support: DOAC, written information, follow-up arranged.
- Admit / hdu — Hypoxia, RV strain, raised troponin, haemodynamic instability, high bleeding risk, or other reasons to admit.
Is there a clerking template for suspected pulmonary embolism (PE)?
Yes — there is a free clerking template for suspected pulmonary embolism (PE) on this page, structured as presenting complaint, red flags asked, history, examination (A–E), investigations, differentials, plan and escalation. You can copy it or download it as a Word document. Jump to the template.
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