Review Question - QID 102725

This patient is presenting with hypotension, tachycardia, and wheezing which is concerning for anaphylaxis. The best initial step in management is IM epinephrine.

Anaphylaxis occurs as a result of an IgE-mediated hypersensitivity that causes mast cell degranulation and histamine release. Patients typically present with a combination of hives, facial edema, pruritis, respiratory difficulty, and hypotension in the setting of an inciting factor (such as a bee sting). Anaphylaxis generally does not occur during the patient’s first exposure to the allergen, instead presenting upon subsequent exposures once IgE has formed against the allergen. Patients with anaphylaxis should immediately be given IM epinephrine. Other medications that should be given subsequently include diphenhydramine, famotidine, and steroids.

Incorrect Answers:
Answer 1: Albuterol would be indicated for an acute asthma exacerbation which presents with wheezing after exposure to an antigen. This patient's symptoms are systemic involving their skin (hives), vasculature (hypotension), and lungs (wheezing) suggesting anaphylaxis.

Answer 2: Continuous monitoring is inappropriate in a patient who is rapidly decompensating secondary to anaphylaxis.

Answer 3: Diphenhydramine would be given to this patient after epinephrine but is not the best initial step in management.

Answer 5: Normal saline may be given after epinephrine is given to this patient; however, epinephrine could rapidly reverse this patient's hypotension while also improving their respiratory status.

Bullet Summary:
Epinephrine is the best initial step in management for anaphylaxis.