Do epinephrine auto-injectors have an unsuitable needle length in children and adolescents at risk for anaphylaxis from food allergy?

Background: Food allergy is the most common cause of anaphylaxis in children. Intramuscular delivery of epinephrine auto-injectors (EAI) is the standard of care for the treatment of anaphylaxis. We examined if children and adolescents at risk of anaphylaxis weighing 15-30 kg and >30 kg would receive epinephrine into the intramuscular space with the currently available EAI in North America and Europe. Methods: The distance from skin to muscle (STMD) and skin to bone (STBD) on the mid third anterolateral area of the right thigh was measured by ultrasound applying either high pressure ((max)) or slight pressure ((min)) in 102 children weighing 15-30 kg (group 1) and 100 children and adolescents, weighing more than 30 kg (group 2). Results: Using a high pressure EAI (HPEAI), Epipen Jr (R) and Auvi-Q (R)/Allerject (R) 0.15 mg, 11/102 (11 %) children in group 1 and 38/102 (38 %) using another HPEAI, Jext (R), had a STMDmax that showed a risk of intraosseous injection. There was a 1 % risk of subcutaneous injection with these devices. There was no risk of intraosseous injection using a low pressure EAI (LPEAI), Emerade (R). In group 2, the risk of intraosseous injection using a HPEAI was 3 % and no risk using a LPEAI. However, the risk of subcutaneous injection using HPEAI was 9 % and using LPEAI was 2 %. Conclusion: There is a risk of intraosseous injection using HPEAI (Epipen (R)/Epipen Jr (R), Auvi-Q (R)/Allerject (R) and especially Jext (R)) in children at risk of anaphylaxis. There was also a risk of subcutaneous injection using the currently available HPEAI in children and adolescents.