Skip to textbook content
Doctor’s PassportTextbook
TopicsAll topics

Loading topic navigation…

Textbook navigation
TopicsAll topics

Loading topic navigation…
Educational draft · awaiting clinical reviewUse Rapid for revision, not patient-care decisions. Check current national and local guidance and the BNF or BNFC before acting.

Massive pulmonary embolism and reperfusion

Respiratory · UK scope · Sources checked 27 Aug 2026 · Clinical review pending

RapidFull
!
Escalate

High-risk PE is a resuscitation emergency. Cardiac arrest, obstructive shock or persistent hypotension requires immediate senior critical-care/reperfusion decision-making; probability scores and D-dimer have no role in delaying treatment.

Synopsis

Recognise high-risk PE from haemodynamic instability and deliver resuscitation, anticoagulation and time-critical reperfusion while avoiding delays caused by routine stable-PE workflows.

  • Prefer the term high-risk PE: risk is defined by haemodynamic instability, not by 'saddle' position or clot size on CT.
  • Recognise cardiac arrest, obstructive shock or persistent hypotension (commonly systolic BP below 90 mmHg or a fall of at least 40 mmHg for more than 15 minutes not explained by another cause).
  • Start ABCDE/ALS, controlled oxygen, monitoring, IV/IO access and immediate critical-care/PE-team input; treat competing reversible causes in parallel.
  • Avoid uncritical large fluid loads: a small 250–500 mL crystalloid challenge may help selected underfilled patients, but RV distension can worsen output; reassess after every bolus.
  • If stable enough, CTPA confirms PE. If too unstable to transfer, focused echocardiography can show RV failure and exclude major alternatives, but RV strain alone is not diagnostic in a stable patient.
  • NICE recommends considering systemic thrombolysis for PE with haemodynamic instability and not offering it routinely to haemodynamically stable PE, even with RV dysfunction.
  • A licensed alteplase regimen for massive PE in adults at least 65 kg is 10 mg IV over 1–2 minutes then 90 mg over 2 hours; below 65 kg, do not exceed 1.5 mg/kg and follow the product schedule.
  • When thrombolysis is contraindicated or fails, urgently consider surgical embolectomy or catheter-directed/mechanical treatment according to expertise and availability.
  • In cardiac arrest from suspected PE, RCUK recommends fibrinolysis; consider continuing CPR for 60–90 minutes after thrombolytic administration.
  • Use UFH when immediate reperfusion/procedures are anticipated because it is rapidly adjustable; record bolus, infusion, APTT/anti-Xa plan and thrombolytic timing.

    • Key red flags

    Cardiac arrest

    PE commonly presents with pulseless electrical activity; very low ETCO2 despite a confirmed airway, appropriate ventilation and high-quality compressions may support but does not prove the diagnosis.

    Obstructive shock

    Hypotension plus altered mental state, cool peripheries, oliguria or raised lactate with signs of RV strain/venous congestion indicates critical circulatory failure.

    Persistent hypotension

    Systolic BP below 90 mmHg or a sustained fall of at least 40 mmHg without arrhythmia, hypovolaemia or sepsis strongly supports the high-risk category.

    Impending collapse

    Syncope, escalating tachycardia, rising lactate, increasing oxygen need, severe RV dysfunction or recurrent near-arrest requires a monitored critical-care setting and an agreed rescue plan.

    Investigation priorities

    01
    Continuous ECG, BP, SpO2 and capnography when intubatedFirst step

    Track shock and detect peri-arrest deterioration.

    Management branches

    ShockHigh-risk PE with a pulse

    Obstructive shock or persistent hypotension with PE confirmed or overwhelmingly likely.

    1. Start ABCDE, controlled oxygen, continuous monitoring, 2 IV/IO lines and immediate critical-care/PE-team activation. Take reperfusion bloods without delaying treatment.
    2. Use cautious 250–500 mL crystalloid only if clinically underfilled and reassess; avoid repeated large boluses that distend the failing RV. Start vasoactive support in critical care when hypotension persists.
    3. If safe, obtain urgent CTPA. If too unstable, use bedside echo/ultrasound to support PE and exclude tamponade, tension pneumothorax and profound hypovolaemia.
    4. If bleeding risk is acceptable, give systemic thrombolysis. If contraindicated, unavailable to succeed or failed, move urgently to surgical embolectomy or catheter-directed/mechanical therapy.
    5. Continue UFH/anticoagulation according to thrombolytic/procedural timing, then monitor for bleeding and RV/organ recovery in critical care.
    Stable RV injuryIntermediate-risk PE surveillance

    Normotensive PE with RV dysfunction and/or myocardial injury but no shock.

    Key medicines

    Alteplase for massive PEBody weight at least 65 kg: 10 mg IV over 1–2 minutes, then 90 mg by IV infusion over 2 hours (total 100 mg). Below 65 kg: total dose must not exceed 1.5 mg/kg; follow the current Actilyse PE dosing table.Major bleeding and intracranial haemorrhage; screen urgently for active bleeding, prior haemorrhagic stroke, recent major surgery/trauma and uncontrolled hypertension. Arrest may change the risk balance. Use only the PE-licensed vial/regimen and coordinate anticoagulation timing.
    Unfractionated heparinRCUK 2025 gives 80 units/kg IV during the diagnostic process unless bleeding or an absolute contraindication is present; continue with a specialist-prescribed IV infusion titrated to the service's APTT or anti-Xa target rather than an unmonitored fixed rate.Active bleeding, HIT history and dosing errors. Check platelets/coagulation; the infusion target and post-thrombolysis restart must be explicitly prescribed and monitored.
    Open full textbook →Answer 2 questions
    Sources and review status5 sources · checked 27 Aug 2026 · clinical review pending+
    Sources

    Sources and review status

    National guidance is shown before implementation-dependent detail. Typical adult dose examples remain subject to patient factors, contraindications and the live BNF or specialist protocol. Source check completed 27 Aug 2026; clinical approval remains outstanding.

    • Resuscitation Council UK 2025: Special circumstancesHigh-risk PE, heparin, reperfusion and PE-arrest recommendations.
    • NICE NG158: Venous thromboembolic diseases—recommendationsSystemic thrombolysis threshold and anticoagulation framework.
    • Actilyse 10 mg SmPCLicensed alteplase regimen, contraindications and safety information for massive PE.
    • BTS guideline for oxygen use in healthcare and emergency settingsAcute oxygen targets and controlled administration.
    • Heparin sodium SmPCUFH treatment information and safety context.

    Editorial contact: Doctor’s Passport editorial team. Source-check date is separate from clinical approval. Report a content problem · Content changes

    Authoring stateRapid draftClinical stateAwaiting reviewJurisdictionUnited Kingdom
    1. Admit to a closely monitored setting, start therapeutic anticoagulation and trend BP, perfusion, oxygen need and mental state.
    2. Do not offer routine systemic thrombolysis while haemodynamically stable under NICE NG158.
    3. Document a rescue-reperfusion plan and activate it if persistent hypotension, shock or arrest develops; re-evaluate bleeding contraindications before deterioration if possible.