Answer: You are correct in that there are proponents for Deltoid IM injection in Anaphylaxis. Proponents of the deltoid route include the American Academy of Allergy Asthma and Immunology (AAAI). This is based on a study examining 13 men to determine when the peak plasma level of epinephrine was reached (not when it’s targeted action was achieved). However, as a whole, the most consistent and safe IM route is via the deltoid due to today’s increasingly adipose-rich population. In fact, a study done examining the EpiPen auto injector (needle length of 1.43cm) found that 42% of the female sample population studied would not be able to reach their IM compartment. Yes, subcutaneous administration will also produce an effect, but much slower than IM due to its less-rich blood supply. Thus, it is base hospital’s recommendation to keep the preferred site of IM Epi injection as the deltoid.
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