Ceftriaxone Infusion and a Hoarse Voice on the Day Unit
A 45-year-old woman attends a day unit for her first dose of IV ceftriaxone for a urinary infection. She has a documented 'rash' with amoxicillin 10 years ago and mild seasonal hay fever, but no previous severe reaction. Ten minutes into the infusion she reports itching, and within two minutes she is flushed, has widespread urticaria, audible wheeze and a hoarse voice. Observations: respiratory rate 30/min, SpO2 91% on room air, heart rate 126/min, blood pressure 84/48 mmHg, temperature 36.8°C, capillary refill 4 seconds. She is anxious and says, 'I think I'm panicking, I just need to sit up.' The infusion is still running. The unit has two nurses, one of whom is newly qualified, and a resuscitation trolley with adrenaline 1 mg/mL ampoules, oxygen and a bag-valve mask. The nearest intensive care unit is 20 minutes away by ambulance.
1. What are your immediate management priorities, and why is adrenaline given by this route and dose?
Read the worked answer
Diagnosis: acute anaphylaxis during IV ceftriaxone - sudden urticaria, wheeze, hoarse voice, hypotension, tachycardia and hypoxia after a known trigger. Hoarseness suggests laryngeal oedema and makes this a time-critical airway emergency. Do not attribute it to panic; anxiety is a symptom, not an alternative diagnosis.
Immediate actions, in order:
- Stop the ceftriaxone infusion and keep IV access.
- Call for help and 999/resuscitation team; direct the newly qualified nurse to bring the trolley, adrenaline, oxygen and bag-valve mask.
- Give adrenaline 0.5 mg (0.5 mL of 1 mg/mL) intramuscularly into the anterolateral thigh immediately. Do not wait for antihistamines, steroids or a doctor. Repeat every 5 minutes if there is no improvement.
- Give high-flow oxygen 15 L/min via a non-rebreathe mask.
- Position supine with legs elevated if tolerated. She wants to sit up because of breathing difficulty; allow a position of comfort if she cannot lie flat, but do not let her stand or walk, because sudden standing can cause fatal empty-ventricle syndrome.
- Give a rapid IV crystalloid bolus of 500–1000 mL for hypotension and monitor continuously.
- Prepare for airway support: call a senior anaesthetist or critical care, have suction and airway adjuncts ready. Intubation may be needed for laryngeal oedema.
Do not: give IV adrenaline unless trained and in a monitored setting; delay adrenaline to give chlorphenamine or hydrocortisone; restart the infusion; or send her alone to the ambulance.
2. After the first adrenaline dose the wheeze improves slightly, but blood pressure is 92/54 mmHg and she remains tachycardic. What next, and what monitoring and observation does she need?
Read the worked answer
She is still in shock. Repeat IM adrenaline 0.5 mg after 5 minutes, continue rapid crystalloid, and call critical care for an adrenaline infusion if she remains hypotensive after two doses and fluid resuscitation. Consider a second large-bore IV line.
Second-line drugs: give chlorphenamine 10 mg and hydrocortisone 200 mg IM/IV only after adrenaline and fluids. They treat skin symptoms and may reduce protracted reactions but do not reverse airway oedema or shock; they are not a substitute.
Monitoring: continuous SpO2, ECG and blood pressure every 5 minutes until stable, then every 15–30 minutes. Watch for recurrent wheeze, stridor, falling blood pressure and reduced consciousness. Record urine output if hypotensive.
Observation: observe for at least 6–12 hours after the last adrenaline dose and resolution of symptoms, because biphasic reactions can occur hours later. Extend observation if the reaction was severe, required repeated adrenaline, or she has asthma or poor access to emergency care.
Investigations: mast cell tryptase ideally within 1 hour of onset, again at 2–4 hours, and a baseline sample after 24 hours. Results support the diagnosis but must never delay treatment.
Before discharge: supply an adrenaline auto-injector with training, a written emergency plan, allergy clinic referral, advice to avoid ceftriaxone and related cephalosporins, and clear instructions to call emergency services for any recurrence.
3. How would you document the reaction and allergy status, and what should be recorded about the previous amoxicillin rash?
Read the worked answer
Document in real time: the drug, dose, route and time of each adrenaline dose; the time of onset and progression of each symptom; observations; fluids; oxygen; who was called and when; and the patient's response.
Allergy record: enter 'ceftriaxone - anaphylaxis (urticaria, wheeze, hoarse voice, hypotension)' in the structured allergy field with the date, reaction type and source. Add an alert visible on prescribing screens. Do not rely on free text alone.
The old amoxicillin rash: a childhood rash labelled as penicillin allergy is often viral and not a true allergy, but the nurse should not relabel it. Record it as reported, with age, timing, rash type and treatment, and refer for allergy assessment. The current reaction is to ceftriaxone, a cephalosporin. Cross-reactivity with penicillins is low overall and is mainly related to similar side chains, such as amoxicillin/ampicillin with cefaclor or cephalexin. However, after anaphylaxis to ceftriaxone she should avoid cephalosporins and penicillins until specialist review.
Communicate: give the patient written information, update the discharge summary, inform the GP, and ensure the day unit and any future admitting team can see the alert. Report the reaction through the local adverse drug reaction scheme.