Anaphylaxis/Anaphylactic Reactions
Description Diagnostic criteria General and supportive measures Medicines treatment Preventative measures and home based treatment Referral ICD 10 code: T78.2 DESCRIPTION An acute, potentially life-threatening hypersensitivity reaction starting within seconds to minutes after administration of, or exposure to, a substance to which the individual is sensitised. Clinical manifestations inclu
General and supportive measures
Preventative measures and home based treatment
ICD 10 code: T78.2
DESCRIPTION
An acute, potentially life-threatening hypersensitivity reaction starting within seconds to minutes after administration of, or exposure to, a substance to which the individual is sensitised. Clinical manifestations include at least one of: upper airway obstruction, bronchospasm, hypotension, or shock.
The reaction can be short-lived, protracted or biphasic, i.e. acute with recurrence several hours later. Immediate reactions are usually the most severe.
DIAGNOSTIC CRITERIA
Clinical
- Acute onset of signs and symptoms.
- Dizziness, paraesthesia, syncope, sweating, flushing, dysrhythmias.
- Swelling of eyes, lips and tongue (angioedema).
- Upper airway obstruction with stridor.
- Hypotension and shock.
- Bronchospasm, wheezing, dyspnoea, chest tightness.
- Gastrointestinal symptoms such as nausea, vomiting, diarrhoea.
A life-threatening anaphylactic reaction requires immediate treatment.
Facilities to initiate treatment must be available at all health centres.
GENERAL AND SUPPORTIVE MEASURES
- Place hypotensive or shocked patient in horizontal position. Do not place in a sitting position.
- Assess and secure airway. If necessary, bag via mask or intubate.
MEDICINE TREATMENT
- Adrenaline (epinephrine) 1:1000 (undiluted), IM, 0.01 mL/kg. (i.e. 10 µg/kg).
- Can be repeated every 5 minutes, if necessary.
- Maximum per dose: 0.5 mL.
Do not administer IV unless there is failure to respond to several doses of IM.
If no response, use IV:
- Adrenaline (epinephrine) 1:1000 (undiluted), IV infusion at 0.02 µg/kg/minute (mix 0.06 mg/kg adrenaline in 50 mL 5% dextrose, 1 mL/hour = 0.02 µg/kg/minute).
To maintain arterial oxygen saturation ≥ 95%:
- Oxygen, at least 1–2 L/minute by nasal prong
- In severe anaphylaxis, nasal oxygen is unlikely to be adequate:
- Oxygen, 15 L/minute by face mask with a reservoir bag.
Crystalloid solutions, e.g.:
- Sodium chloride 0.9% OR Modified Ringers Lactate, IV, 20 mL/kg rapidly.
- Repeat if necessary until circulation, tissue perfusion and blood pressure improves (up to 60 mL/kg).
- Hydrocortisone, IV, 5 mg/kg, 4–6 hourly for 12–24 hours.
Note: Steroids are adjunctive therapy, are not part of first line treatment, and should never be the sole treatment of anaphylaxis.
- Promethazine, IV/IM, 0.25–0.5 mg/kg/dose. Contra-indicated in children < 2 years old.
Continue with:
- Chlorphenamine, oral, 0.1 mg/kg/dose 6 hourly for 24–48 hours, if necessary.
If associated bronchospasm:
- Salbutamol, nebulised, 1 mL salbutamol respirator solution in 3 mL sodium chloride 0.9%.
- Nebulise at 20-minute intervals.
If associated stridor:
- Adrenaline (epinephrine), 1:1000, nebulise with oxygen, every 15–30 minutes until expiratory obstruction is abolished.
- 1 mL adrenaline (epinephrine) 1:1000 diluted in 1 mL sodium chloride 0.9%.
Observe for 24 hours, in particular for recurrent symptoms as part of a ‘biphasic’ reaction.
PREVENTATIVE MEASURES AND HOME BASED TREATMENT
- Obtain a history of allergies/anaphylaxis on all patients before administering medication/immunisation.
- Identify offending agent and avoid further exposure.
- Ensure patient wears allergy identification disc/bracelet.
- Train patients to self-administer epinephrine pre-filled auto injecting device. Specialist initiated for patients who have anaphylactic reactions.
- Educate patient and parent/caregiver on allergy and anaphylaxis.
REFERRAL
Caution:
Do not refer the patient during the acute phase.
Transfer can only be done once patient is stable.
Patients supplied with self-administered epinephrine must be informed of the shelf life of epinephrine and when they must come in to get a replacement.
- Bee sting anaphylaxis for desensitisation.
Standard Treatment Guidelines And Essential Medicines List For South Africa, Hospital Level, Paediatrics, 2023 Edition
Chapter 1: Emergencies and Trauma, 1.1 Paediatric Emergencies, 1.1.3 Anaphylaxis/anaphylactic Reactions