Management of Anaphylaxis in Healthcare Settings
Appropriate preparation is the key to good patient outcomes in anaphylaxis. In a pediatric ED, development and implementation of an anaphylaxis protocol significantly improved the rate of epinephrine administration, the rate of admission to an observation unit, and the duration of observation in this unit, and there were no significant adverse effects from epinephrine. In a retrospective study. of pediatric ED patients with food-related allergic reactions, factors that were independently associated with a higher likelihood of hospitalization included pre-ED epinephrine treatment, and epinephrine treatment within 1 h of triage.
Epinephrine is the preferred vasopressor for treatment of anaphylactic shock; however, it is not always given promptly, even in hospitalized patients. As an example, anaphylaxis can be difficult to diagnose during anesthesia; consequently, treatment with epinephrine can be delayed. In a retrospective study, 45% of patients with anaphylaxis during anesthesia developed shock, circulatory instability, or cardiac arrest, yet only 83% of these patients received epinephrine.
Even if epinephrine has not been given at all, cardiovascular symptoms, including myocardial infarction and arrhythmias, can occur during anaphylaxis. These complications also occur after epinephrine overdose, regardless of route of administration, but especially after an intravenous bolus dose or overly rapid intravenous infusion.
In a prospective randomized blinded study of young patients with acute cutaneous allergic reactions during food challenges, in comparison with diphenhydramine 1mg/kg, cetirizine 0.25mg/kg had a similar onset of action, similar efficacy, longer duration of action, and reduced sedation profile. A similar number of children in each treatment group were treated with epinephrine and glucocorticoids.