15 Month-old with Known Peanut Allergy

0.01 mg/kg (1mg/ml) IM epinephrine. 

This patient meets criteria for anaphylaxis as she is presenting with acute hypotension after exposure to a known or highly probable allergen even in the absence of skin involvement. 

Hypotension is defined as a decrease in systolic blood pressure of 30% from the patient’s baseline, or for infants 1 month- 1 year, a systolic blood pressure < 70 mmHg, for infants and children < 10 years of age, a systolic blood pressure less than 70 mmHg + 2 x age (years)), and for children and adolescents 11-17 years old a systolic BP < 90 mmHg.  

Anaphylaxis criteria is also met if there is acute onset of an illness (minutes to several hours) with skin or mucosal involvement or both (i.e., hives, pruritis, flushing, swelling of the lips, uvula, tongue) AND any one of the following: respiratory compromise, hypotension, or end organ dysfunction (syncope, incontinence) or severe gastrointestinal symptoms (i.e., crampy abdominal pain, multiple episodes of vomiting). 

The first line treatment for anaphylaxis is 0.01 mg/kg of the 1mg/ml concentration of IM epinephrine to the anterolateral thigh. Bolus doses of IV epinephrine are not recommended because it can cause fatal arrythmias. Fluid boluses can be added as an adjunct to replete intravascular volume secondary to the increased vessel permeability. 

[Cardona et al. 2020, Campbell and Kelso UTD]