Epinephrine Auto-Injectors for Anaphylaxis: A Review of the Clinical Effectiveness, Cost-Effectiveness, and Guidelines [Internet]

Excerpt

Anaphylaxis is a potentially life-threatening medical emergency which requires prompt recognition and treatment. The condition is caused by a severe and generalized allergic reaction or hypersensitivity reaction that leads to a sudden release of mast cell and basophil-derived mediators into circulation.^, Onset of a range of clinical symptoms occurs rapidly, and includes severe airway, breathing, and circulation problems. Common causes of anaphylaxis are medication reactions, insect stings, and food allergies.

Epinephrine is the usual treatment for patients experiencing anaphylactic reactions, and the administration of this treatment should be rapidly executed. Epinephrine has several mechanisms of action that reduce and reverse the symptoms of anaphylaxis.^, It works to decrease vasoconstriction and peripheral vascular resistance, decrease upper airway mucosal edema, increase bronchodilation, and decrease mediator release from mast cells and basophils. Delayed administration of epinephrine is associated with poorer outcomes for the patient, emphasizing the importance of prompt treatment. First-line emergency treatment with epinephrine is generally by intramuscular (IM) injection, which can either be administered by an epinephrine auto-injector (EAI) or by manual draw-up and dosing from an epinephrine containing ampoule or vial. Depending on the setting, epinephrine can be administered by the patients experiencing the reaction, by a caretaker, or by various health care professionals.^, There is uncertainty as to which method of IM delivery of epinephrine is preferable in health care settings, and whether EAI or epinephrine vials for manual delivery should be stocked and available for use by health care professionals.

In order to inform policy decisions about the use of either EAI or manual delivery of epinephrine, specific evidence is required. As such, this report aims to review the comparative clinical effectiveness and cost-effectiveness of EAI versus manually administered epinephrine for the management of individuals with anaphylaxis. Additionally, the report aims to review the evidence-based guidelines for the management of anaphylaxis.