On a night when ghosts roam and pumpkins glow, few things are truly as terrifying as the sudden onset of anaphylaxis. Unlike the imagined horrors of Halloween, this real-life medical emergency strikes without warning, transforming a festive moment into a fight for survival. This severe, rapid-onset allergic reaction can transform an ordinary moment into a true medical emergency within minutes. In the prehospital setting, prompt recognition and immediate intervention are critical to patient survival.
Background
Allergies affect up to 21 million people in the UK. Anaphylaxis is a severe, potentially life-threatening, allergic reaction that can compromise the airway, breathing, and circulation rapidly.
A 2020 Canadian study found that the incidence of nut-related anaphylaxis increased around Halloween. A stray peanut in a child’s bag of Halloween sweets can spell disaster, so it is essential to recognise the signs.
Anaphylaxis is a type 1 hypersensitivity reaction in which IgE causes the release of inflammatory chemicals, including histamine, from mast cells in response to a foreign antigen. This causes skin reactions, including urticaria and pruritus, as well as angio-oedema, which often affects the face but also can affect the airway. It also causes vasodilation and increased vascular permeability, resulting in hypotension and shock.
Assessment
Patients with anaphylaxis may present with shortness of breath, wheeze, angioedema, and urticaria. They may be aware of recent allergen exposure.
Assessment should follow the ABCDE framework, with management of each issue before moving on to the next step in assessment. As per NICE guidelines, first look for and treat airway obstruction. Then ensure adequate oxygen is given, and if there is wheeze (especially if the patient has known asthma), consider salbutamol and ipratropium. Cardiovascular examination should include pulse and blood pressure to assess for signs of haemodynamic instability.
Management
The Resuscitation Council UK provides algorithms for the treatment of anaphylaxis and refractory anaphylaxis.
The trigger for anaphylaxis should be removed if the patient is still in contact with this. The patient should be lying flat to help maintain blood pressure, unless there are breathing difficulties, in which case they may need to be sitting up. Pregnant patients should be positioned on their left side. It is key that patients with acute anaphylaxis should not stand, walk, or sit up suddenly to avoid any sudden drop in blood pressure.
The hallmark of anaphylaxis management is the administration of adrenaline. Some patients will have adrenaline auto-injectors if they are known to have allergies and may have already administered these. Intramuscular adrenaline should be administered into the anterolateral aspect of the middle third of the thigh or arm. The dose is based on age and often is stocked as 1ml vials with a concentration of 1:1000 (1mg/ml). In adults, the recommended dose is 500 micrograms, which would be 0.5ml.
The response to adrenaline should be assessed with vital signs monitoring. The dose can be repeated every 5 minutes. If there is no response after two doses, the refractory anaphylaxis algorithm should be followed. Some patients may require an IV adrenaline infusion, which would require critical care admission; therefore, timely transfer to the hospital is essential.
Tachycardia and hypotension indicate circulatory collapse and should be treated with a rapid fluid bolus.
Conclusion
In the spirit of the season, Halloween reminds us that not all threats are visible, and not every scare can be anticipated. Anaphylaxis remains one of the most time-sensitive emergencies encountered in prehospital settings, and every second counts. Vigilance, swift assessment, and timely administration of adrenaline are the key elements that turn potential tragedy into recovery.
References
Image Source: Resuscitation Council UK: Anaphylaxis.
Resuscitation Council UK: Anaphylaxis.
Resuscitation Council UK: Refractory Anaphylaxis.
If you enjoyed this article, consider checking out “Spooktacular Scenarios: When the Vampire Strikes (Pre-Hospital Haemorrhage Management).“
Written by: Dr Brogan Tierney (FY2)
Edited by: Dr Maria Kent (FY2, MTB Pre-Hospital Lead)
Reviewed By: Dr Callum Carruthers (GP with a special interest in Emergency Medicine, and responder with BASICS Scotland)
