Wasp sting at a festival: anaphylaxis, one spare auto-injector, 12 minutes out
15:30 at an outdoor food festival where you are the site first aider. A 29-year-old steward staggers into the first aid tent and says she has been stung by a wasp on the wrist 5 minutes ago. She has a blotchy red rash spreading up her arm and across her chest, her lips and eyelids look puffy, and she is wheezing. She can only speak three or four words at a time. She is frightened, says she feels faint, and wants to sit on the chair and then walk to the gate to meet the ambulance. She has a known wasp allergy and her own adrenaline auto-injector in her bum bag; the site first aid kit holds one spare auto-injector (0.3 mg) and an asthma spacer with salbutamol. The ambulance has been called and is 12 minutes away.
1. Why is this anaphylaxis rather than asthma or a panic attack?
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The reasoning is about speed, systems and pattern.
Speed. Symptoms started within 5 minutes of a sting and are progressing. Asthma and panic attacks do not behave like that after a sting in someone with a known wasp allergy.
Systems involved. Anaphylaxis is defined by sudden-onset, rapidly progressing airway, breathing or circulation problems, usually with skin or mucosal changes. She has three groups at once:
- Skin and mucosa: spreading blotchy rash, puffy lips and eyelids.
- Breathing: wheeze, and she can only manage three or four words.
- Circulation: she feels faint.
Against asthma: asthma gives wheeze and difficulty speaking, but not spreading urticaria, not lip and eyelid swelling, and it does not usually follow a sting within minutes in this way.
Against a panic attack: panic gives fast breathing and tingling and a sense of doom, but the chest would sound clear, there would be no urticaria and no mucosal swelling, and she would not have the puffy lips.
The safe rule is: when in doubt, treat as anaphylaxis. Delay in giving adrenaline is the main avoidable cause of death.
2. Set out your immediate management, including positioning, the auto-injector, and the rules on a second dose.
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Position first. She must not sit in the chair and must not walk to the gate. Standing or sitting a severely affected casualty upright can drop venous return to a nearly empty heart and cause cardiac arrest. I would lay her flat with her legs raised on a box or chair. If her breathing worsens, I let her sit up slightly, but her legs stay raised and she does not stand.
Adrenaline. Her own auto-injector first: outer mid-thigh, anterolateral, and it can go through clothing. Hold it in place for the time the device states - 3 seconds for an EpiPen, 10 seconds for Jext, 5 seconds for Emerade - then remove it, note the time, and put the used device safely aside for the crew. Check the expiry date as I take it out.
Second dose. If there is no improvement after 5 minutes, or she deteriorates, I give the spare 0.3 mg device from the site kit into the other thigh. I note both times and doses.
Alongside this: 999 with the word 'anaphylaxis'; keep her warm; nothing by mouth, including the salbutamol - a spacer might ease wheeze but it is not the treatment for anaphylaxis and must not delay adrenaline; watch breathing continuously and be ready for CPR.
3. She becomes drowsy and then unresponsive, still breathing noisily. What now, and what do you hand over?
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Unresponsive but breathing. Adrenaline is already in. I would place her in the recovery position to protect the airway, keep monitoring breathing, and be ready to move straight to CPR. If the noisy breathing deteriorates into no breathing or only occasional gasps, that is a cardiac arrest in anaphylaxis: start CPR at 30:2, get the AED, and keep going - the crew will give further adrenaline and fluids.
Handover to the paramedics:
- Time of the sting and the site, and that it was a wasp.
- Time of first symptoms and what they were, in order.
- That she has a known allergy and carries her own device.
- Time of each adrenaline dose, which device, which thigh, the dose (0.3 mg), and the batch/expiry if visible.
- Position and changes in her level of response, with times.
- That nothing was given by mouth.
The record I write afterwards mirrors this, with my name and signature, and notes that she was unable to consent once drowsy and was treated in her best interests.