Sitting next to my son, who is rather red-cheeked with his current fever, consuming a herculean amount of cartoons, I was reminded of one of my favorite shows when I was young: GI JOE. “Knowing is half the battle,” was imprinted within my being at an early age. The Morsels have addressed many topics that hopefully augmented everyone’s “knowing.” One topic that deserves some attention is Anaphylaxis.

{Yes, we just went from my febrile son, to GI JOE, to Anaphylaxis. That is the transitive property of Morsel writing.}

Anaphylaxis: More Common than you Think

The incidence has increased with the implementation of the broader definition.

The incidence ranges from 100,000 to 500,000 per year in the USA .

. Two-thirds of the annual cases are new cases.

Almost 1% of cases are fatal .

. The incidence in food-related allergies has been increasing, so it is expected that anaphylaxis will also increase.

Estimated that a food-induced anaphylaxis presents to the ED every 6 minutes in the USA.

Anaphylaxis: The Criteria

The National Institute of Allergy and Infectious Diseases define anaphylaxis as a “serious allergic reaction that is rapid in onset and may cause death” and typically involves two or more organ systems.

Anaphylaxis is highly likely when ANY of the following criteria are met : Acute Onset with involvement of skin, mucosal surfaces, or both AND Respiratory Compromise and/or Reduced BP or symptoms of end-organ dysfunction Two or more of the following that occur rapidly after exposure to a likely allergen: Skin/Mucosal tissue involvement Respiratory Compromise Reduced BP or symptoms of end-organ dysfunction Persistent GastroIntestinal symptoms (ex, crampy pain, vomiting) Rapid reduction in BP after exposure to known allergen .

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Anaphylaxis: Important Points

The severity of an anaphylactic reaction cannot be predicted based on past reactions or risk factors.

based on past reactions or risk factors. Young children are tricky! As with most conditions, the very young can be more difficult to diagnose. The preverbal may not be able to express their symptoms clearly.

GastroIntestinal Symptoms are important to consider! They are often under appreciated. They have been found in over 50% of cases.

BiPhasic Reactions: Occur in about 6% – 11% of children. Usually manifest within the first 8 hours after exposure, but may be delayed up to 72 hours.

Treatment: Epinephrine is the preferred 1st line therapy. Antihistamines (H1 and H2 blockers) are useful for urticaria, nasal, and ocular symptoms, but not other symptoms . Steroids have too slow of an onset to matter in the acute phase.



Anaphylaxis: “Epi Early and Often!”

Epi Early! Epinephrine is the 1st line therapy for acute anaphylaxis . Delayed administration of epinephrine has been associated with increased morbidity and mortality. Unfortunately, several studies indicate that Epinephrine is either given in a delayed fashion or not at all during the acute phase. This is true for patients/parents, EMS providers, as well as physicians. Dose: 0.01 mg/kg of the 1:1,000 solution ; Max of 0.3 mg in children (0.5 mg in adults). Autoinjectors: 0.15 mg dose for pts < 25kg; 0.3 mg for pts < 25 kg. Exact dose is preferred for small infants and children. Route Matters! Intramuscular (IM) administration into the mid-anterolateral thigh is preferred . IM provides faster rise in plasma and tissue concentrations than does the subcutaneous route.



Epi Often! Epinephrine has a short half-life. May need to repeat dose after 5 minutes . Up to 20% of patients require more than one dose ! It is important to ensure patients have at least 2 doses of self-administered Epinephrine available to them in different environments (So prescribe 2 for home, 2 for school, etc).



There are no absolute contraindications to Epinephrine in this clinical setting . Often concerns over adverse effects of epinephrine can delay it being given. Appropriate doses of epinephrine rarely cause severe adverse reactions.

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Moral of the Morsel: Epi Early and Often

Keep the broader criteria of Anaphylaxis on your radar screen.

Ask specifically about GI symptoms.

If the patient meets criteria, give Epi without Delay and consider additional dose in 5 minutes if not improving.

and if not improving. Get access and give IVF.

Other meds like antihistamines should not be given instead of Epinephrine. They can be used as adjuncts, but do not let them distract the team from getting the Epinephrine in!

Patients then will require either prolonged observation (no standard, but often recommended to be 4-6 hrs) or hospitalization.

References