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Anaphylaxis: assessment and referral after emergency treatment

List of all recommendations

  • Document the acute clinical features of the suspected anaphylactic reaction (rapidly developing, life-threatening problems involving the airway [pharyngeal or laryngeal oedema] and/or breathing [bronchospasm with tachypnoea] and/or circulation [hypotension and/or tachycardia] and, in most cases, associated skin and mucosal changes)
  • Record the time of onset of the reaction
  • Record the circumstances immediately before the onset of symptoms to help to identify the possible trigger
  • After a suspected anaphylactic reaction in adults or young people aged 16 years or older, take timed blood samples for mast cell tryptase testing as follows:
    • a sample as soon as possible after emergency treatment has started
    • a second sample ideally within 1–2 hours (but no later than 4 hours) from the onset of symptoms
  • After a suspected anaphylactic reaction in children younger than 16 years, consider taking blood samples for mast cell tryptase testing as follows if the cause is thought to be venom-related, drug-related or idiopathic:
    • a sample as soon as possible after emergency treatment has started
    • a second sample ideally within 1–2 hours (but no later than 4 hours) from the onset of symptoms
  • Inform the person (or, as appropriate, their parent and/or carer) that a blood sample may be required at follow-up with the specialist allergy service to measure baseline mast cell tryptase
  • Adults and young people aged 16 years or older who have had emergency treatment for suspected anaphylaxis should be observed for 6–12 hours from the onset of symptoms, depending on their response to emergency treatment. In people with reactions that are controlled promptly and easily, a shorter observation period may be considered provided that they receive appropriate post-reaction care prior to discharge
  • Children younger than 16 years who have had emergency treatment for suspected anaphylaxis should be admitted to hospital under the care of a paediatric medical team
  • After emergency treatment for suspected anaphylaxis, offer people a referral to a specialist allergy service (age-appropriate where possible) consisting of healthcare professionals with the skills and competencies necessary to accurately investigate, diagnose, monitor and provide ongoing management of, and patient education about, suspected anaphylaxis
  • After emergency treatment for suspected anaphylaxis, offer people (or, as appropriate, their parent and/or carer) an appropriate adrenaline injector as an interim measure before the specialist allergy service appointment
  • Before discharge a healthcare professional with the appropriate skills and competencies should offer people (or, as appropriate, their parent and/or carer) the following:
    • information about anaphylaxis, including the signs and symptoms of an anaphylactic reaction
    • information about the risk of a biphasic reaction
    • information on what to do if an anaphylactic reaction occurs (use the adrenaline injector and call emergency services)
    • a demonstration of the correct use of the adrenaline injector and when to use it
    • advice about how to avoid the suspected trigger (if known)
    • information about the need for referral to a specialist allergy service and the referral process
    • information about patient support groups
  • Each hospital trust providing emergency treatment for suspected anaphylaxis should have separate referral pathways for suspected anaphylaxis in adults (and young people) and children

Care pathway

Anaphylaxis care pathway algorithm

full guideline available from…
National Institute for Health and Care Excellence, Level 1A, City Tower, Piccadilly Plaza, Manchester, M1 4BT
www.nice.org.uk/guidance/CG134

National Institute for Health and Care Excellence. Anaphylaxis: assessment and referral after emergency treatment. December 2011
First included: January 2012.