Pulmonary Embolism – PE

PE is somehow both the most over and under diagnosed condition. with severity ranging from the questionable sub-segmental PE to the Massive PE (an indication for thrombolysis). So think:

  • Does this presentation sound like a PE? – If not STOP here
  • Pregnant?  – Click Here
  • Do you think this is likely a PE? (if so you can’t use PERC)
  • Does D-Dimer answer  your question? (whats the Wells)
  • Massive PE  – think Thrombolysis
  • Sub-Massive PE – there is lots of debate (involve seniors), locally needs 2 consultant sign off and not considered time critical.

Step 1 – Wells Score

PE Wells - Clinical FeatureScore
Clinical signs and symptoms of DVT (minimum of leg swelling and pain with palpation of the deep veins)3
An alternative diagnosis is less likely than PE3
Heart rate > 100 beats per minute1.5
Immobilisation for more than 3 days or surgery in the previous 4 weeks1.5
Previous DVT/PE1.5
Malignancy (on treatment, treated in the last 6 months, or palliative)1
Risk Based ActionScore
High Risk PathwayOver 4
Low Risk Pathway4 and under
Consider PERC - to avoid further investigationUnder 3

PERC (Wells ≤2)

PERC - Clinical FeatureScore
Age <50yrs1
Pulse <100bpm1
SaO2 >94%1
No Unilateral Leg Swelling1
No Haemoptysis1
No Recent Trauma/Surgery1
No Previous PE/DVT1
No Hormone Use/Pregnant1
Risk Based ActionScore
Risk of PE <2%, may stop investigating8
Low Risk PathwayUnder 8

Low Risk Pathway – D-Dimer

  • D-Dimer <500ng/ml – No further investigation is required (be aware in the original studies this did miss patients but none of those had adverse out comes)
  • D-Dimer 500-1000ng/ml – Consultants/MG’s can consider using age adjusted D-Dimer in the over 50’s (10ng/ml per year of age), as D-Dimer elevates with age, however do make sure its truly is a low risk patient. If above cut-off or unable to apply follow High-Risk Pathway.
  • D-Dimer >1000ng/ml – Follow High Risk Pathway

High Risk Pathway – CTPA

  • D-Dimer is irrelevent if Wells >4
  • Commence Tinzaparin – if not contraindicated; [BNF]
  • Order CTPA (consider VQ if Pregnancy)– Remember to input Wells, eGFR, and D-dimer (if low risk) in to clinical details
  • Consider AAU or AMU – dependant on sPESI
sPESI - Clinical FeatureScore
Over 80yrs old1
History of Cancer1
Chronic cardiopulmonary disease1
HR >109bpm1
sBP <100mmHg1
SaO2 <90%1
AMU / MAU1 or more

Sub-Massive PE

Treatment of submissive PE is controversial, there is a theoretical reduction in morbidity if these patients get thrombolysis, however, there are significant risks.

  • Definition: PE & 1 of; RV dilatation, New RBBB, Troponin rise
  • Thrombolysis: 2 consultant decision – not time critical so could wait for ward round

Massive PE – Thrombolysis

Either (confirm with scan if at all possible):

  • CTPA/Echo evidence of PE and features of shock (Systolic BP < 90mmg Hg or a pressure drop of > 40mmHg in < 15 minutes)
  • Periarrest (unsuitable for imaging) and high clinical suspicion of pulmonary embolism)


  • Heparin 80unit/kg OR treatment dose Tinzaparin – (Give Prior to Urgent CTPA)
  • Alteplase (tPA)
    • Non-Arrest – 10mg by IV injection over 1‐2 minutes followed by IV infusion of 90mg over 2 hours; max 1.5mg/kg in patients less than 65kg 
    • Cardiac Arrest – 50mg IV injection over 1-2min
    • Tenecteplase is a suitable alternative if alteplase not immediately available
      • BUT… increased chances major  bleeds inc. fatal intracranial bleeds

Contraindications for Thrombolysis (PE)

“Contraindications to thrombolysis that are considered absolute, e.g. in acute myocardial infarction, might become relative in a patient with immediately life-threatening high-risk PE.”


  • Haemorrhagic stroke or stroke of unknown origin at any time
  • Ischaemic stroke in preceding 6 months
  • Central nervous system damage or neoplasm
  • Recent major trauma/surgery/head injury (within preceding 3 weeks)
  • Gastrointestinal bleeding within the last month
  • Known bleeding


  • Transient ischaemic attack in preceding 6 months
  • Oral anticoagulant therapy
  • Pregnancy or within 1 week post-partum
  • Non-compressible punctures
  • Traumatic resuscitation
  • Refractory hypertension (systolic blood pressure >180 mmHg)
  • Advanced liver disease
  • Infective endocarditis
  • Active peptic ulcer

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.