Sudden onset systemic life-threatening allergic reaction to food


Sudden onset systemic life-threatening allergic reaction to food, medication, contrast material, anaesthetic
agents, insect sting or latex, involving either:
• Circulatory failure (shock)
• Difficulty breathing from 1 or more of following:
• stridor
• bronchospasm
• rapid swelling of tongue, causing difficulty in swallowing or speaking (hoarse cry)
• Acute clinical features
• Time of onset of reaction
• Circumstances immediately before onset of symptoms
:writing_hand::writing_hand:IMMEDIATE TREATMENT
• Remove allergen if possible
• Call for help
• IM adrenaline: dose by age or 10 microgram/kg:
• 0.1 mL/kg of 1:10,000 in infants (up to 10 kg = 1 mL)
• 0.01 mL/kg of 1:1000 (max 0.5 mL = 0.5 mg)
• give in anterolateral thigh
• ABC approach: provide BLS as needed
• if airway oedema, call anaesthetist for potential difficult airway intubation
• if not responding to IM adrenaline, give nebulised adrenaline 1:1000 (1 mg/mL) 400 microgram/kg (max
5 mg)
• treat shock with sodium chloride 0.9% 20 mL/kg bolus
• monitor SpO2, non-invasive blood pressure and ECG
• Repeat IM adrenaline after 5 min if no response, consider IV infusion
:point_right:Do not give adrenaline intravenously except in cardiorespiratory arrest or in resistant shock (no
response to 2 IM doses)
• Admit for a minimum of 6 hr to detect potential biphasic reactions and usually for 24 hr, especially in
following situations:
• severe reactions with slow onset caused by idiopathic anaphylaxis
• reactions in individuals with severe asthma or with a severe asthmatic component
• reactions with possibility of continuing absorption of allergen
• patients with a previous history of biphasic reactions
• patients presenting in evening or at night, or those who may not be able to respond to any deterioration
• patients in areas where access to emergency care is difficult
• Monitor SpO2, ECG and non-invasive BP, as a minimum
• Sample serum (clotted blood – must get to immunology immediately) for mast cell tryptase at the
following times if clinical diagnosis of anaphylaxis uncertain and reaction thought to be secondary to
venom, drug or idiopathic :
• immediately after reaction
• 1–2 hr after symptoms started when levels peak
• >24 hr after exposure or in convalescence for baseline
• If patient presenting late, take as many of these samples as time since presentation allows.
Pediatric guidelines 2018…