Suspected Anaphylaxis During a Routine Appointment
You are an allied health practitioner in an outpatient clinic. Ten minutes after receiving an intramuscular antibiotic injection, a 30-year-old patient reports throat tightness, widespread itching and dizziness. On assessment: swollen lips, widespread urticaria, respiratory rate 28/min, audible wheeze, heart rate 130/min, blood pressure 88/50 mmHg, SpO2 93% on room air. The clinic has an emergency bag containing adrenaline 1 mg/mL ampoules, oxygen, and a defibrillator. A colleague is available.
1. Outline your immediate emergency management using a structured approach.
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Recognise: this is anaphylaxis - acute onset with airway (throat tightness, lip swelling), breathing (wheeze, RR 28, SpO2 93%) and circulation (HR 130, BP 88/50, dizziness) involvement after a likely trigger (the injection).
Call for help and activate the emergency response/ambulance immediately; note the time.
Airway/Breathing: position the patient supine with legs elevated (sit up only if breathing is very difficult); give high-flow oxygen; be prepared for airway swelling.
Adrenaline (first-line): give intramuscular adrenaline into the anterolateral thigh per the local protocol/anaphylaxis guideline dose for adults (commonly 0.5 mg IM of 1 mg/mL solution). Repeat after 5 minutes if no improvement, per protocol. Adrenaline is first-line - do not delay it for antihistamines or steroids.
Circulation: monitor BP and pulse continuously; IV fluids may be required by the responding clinician.
Monitor and reassess every few minutes; be ready for CPR and use the defibrillator if cardiac arrest occurs. Document times, doses, and response. Transfer to hospital for observation even if the patient improves, because of the risk of a biphasic reaction.
2. A colleague says, 'Let's give an antihistamine first and see if it settles.' How do you respond, and what documentation is required?
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Response: politely but firmly correct this. Antihistamines do not treat airway obstruction or hypotension and must not delay adrenaline, which is the only first-line treatment for anaphylaxis. Delay risks deterioration and death. Administer adrenaline per protocol now, with oxygen and positioning, and call for emergency transfer.
Documentation: record the time of onset and trigger, the full observations at each stage, the time and dose of adrenaline and any repeat doses, oxygen flow, positioning, fluids, the time emergency services were called, and the patient's response. Record any advice given and the transfer destination. Complete an incident/adverse drug reaction report per local policy and inform the prescriber.
Key principle: in anaphylaxis, speed and the correct first-line drug matter more than hierarchy - challenge unsafe suggestions calmly and act within your protocol.