Underuse of Epinephrine for the Treatment of Anaphylaxis in the Prehospital Setting.

Background: Anaphylaxis is a life-threatening reaction. Its key management is rapid diagnosis and prompt administration of intramuscular epinephrine. There are many barriers to epinephrine use.

Objective: To assess the performance of dispatchers at suspecting anaphylaxis, proposing epinephrine treatment, helping find an epinephrine autoinjector (EAI) and using it.

Methods: This is a retrospective study. Calls classified as "anaphylaxis" or "allergy" were included, and voice recordings were reviewed. Clinical, environmental, and operational variables were collected. Anaphylaxis was suspected if sudden dyspnoea, abdominal symptoms (vomiting, abdominal pain, or diarrhoea), dizziness, or loss of consciousness were present.

Results: The dispatch handled 120,618 dispatch calls. Dispatchers suspected 611 (0.5%) cases of allergy. Among those, 437 (72%) were deemed consistent with anaphylaxis: 65 patients received epinephrine prior to the dispatcher's advice, and dispatchers proposed the use of an EAI to 141 patients (38%). An EAI was available in 45 situations. The proposition was accepted on 18 cases and performed in 16 cases. The median time from the EAI being in hand and the injection was 50 seconds.

Conclusions: Trained dispatchers are able to suspect anaphylaxis, decide when to treat and provide guidance on using an EAI, although their performance can be improved. There is a need for easier access to EAIs in public places.