3-5. Circulatory embolus

Objectives

Causes: thrombus, fat, amniotic fluid, air/gas.

Signs: hypotension, tachycardia, hypoxemia, decreased ETCO2

Symptoms: dyspnoea, anxiety, tachypnoea. Also consider if sudden unexplained loss of cardiac output.

START

❶ Call for help and inform theatre team of problem. Note the time.

❷ Call for cardiac arrest trolley.

❸ Stop all potential triggers. Stop surgery.

❹ Give 100% oxygen and ensure adequate ventilation:

  • Maintain the airway and, if necessary, secure it with tracheal tube.

❺ If indicated start CPR immediately (CPR can help disperse air emboli and large thrombi).

❻ Give i.v. crystalloid at a high infusion rate. (Adult: 500-1000 ml, Child: 20 ml.kg-1)

  • Inotropes may be required to support circulation.

❼ Treat according to suspected embolus type (see Boxes A-D) whilst considering alternative diagnoses (Box E).

❽ Consider investigations to help confirm diagnosis:

  • Arterial blood gases (increased PaCO2-ETCO2 gradient).
  • Transoesophageal echocardiography (right heart strain, pulmonary arterial emboli).
  • Computerised tomography.

If cardiovascular collapse refractory to treatment, consider extra-corporeal membrane oxygenation (ECMO) or intra-aortic balloon counter-pulsation.

❿ Plan transfer of the patient to an appropriate critical care area.

 

Box A: THROMBOEMBOLISM

Consider thromboembolism e.g. alteplase 10 mg i.v. then 90 mg over 2 h (>65kg)

Consider surgical removal - consult vascular surgeon

Consider percutaneous removal - consult radiologist

Box B: FAT EMBOLISM

  • Petechial rash, desaturation, confusion/irritability if patient conscious
  • Supportive measures are mainstay of initial management

Box C: AMNIOTIC FLUID EMBOLISM

  • Supportive measures are mainstay of initial management
  • Monitor the fetus, if undelivered
  • Treat coagulopathy (fresh frozen plasma, cryoprecipitate and/or platelets)
  • Consider plasmaphoresis

Box D: AIR/GAS EMBOLISM

  • "Mill wheel" murmur may be present
  • Discontinue source of air/gas if applicable and discontinue N2O
  • Tell surgeon to flood wound with saline and cover with wet packs
  • Lower surgical field to below level of heart if possible
  • Place patient in left lateral position if possible
  • If central venous catheter in situ, attempt to aspirate air
  • Volume loading and Valsalva manoeuvre may help

Box E: ALTERNATIVE DIAGNOSES

  • Pneumothorax (+/- tension)
  • Bronchospasm (→ 3-4) 
  • Pulmonary oedema
  • Cardiogenic shock
  • Hypovolaemia
  • Myocardial failure
  • Sepsis (→ 3-14)
  • Bone cement implantation syndrome
  • Anaphylaxis (→ 3-1)

Editorial Information

Last reviewed: 30/09/2018

Author(s): The Association of Anaesthetists of Great Britain & Ireland 2018.-19. www.aagbi.org/qrh Subject to Creative Commons license CC BY-NC-SA 4.0. You may distribute original version or adapt for yourself and distribute with acknowledgement of source. You may not use for commercial purposes. Visit website for details. The guidelines in this handbook are not intended to be standards of medical care. The ultimate judgement with regard to a particular clinical procedure or treatment plan must be made by the clinician in the light of the clinical data presented and the diagnostic and treatment options.

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