Perioperative Anaphylaxis: Comment.

Abstract

We read with interest the clinical focus review “Perioperative Anaphylaxis” by Tacquard et al.1 The authors address management of perioperative anaphylaxis and the use of epinephrine, stating specifically, “Unlike out-of-hospital anaphylaxis where intramuscular epinephrine is the cornerstone of management, intravenous epinephrine, and potentially other vasoactive agents are important for initial management, as noted in advanced cardiac life support algorithms titrated to specific effects.” They reference international consensus recommendations published in 2019 by a group of experts in perioperative allergy, which recommends the IV route for administration of epinephrine.2 However, in 2020, the American Academy of Allergy, Asthma and Immunology (Milwaukee, Wisconsin) published a systematic review and practice parameter update for anaphylaxis recommending intramuscular injection of epinephrine to the anterolateral thigh as first-line therapy for anaphylaxis.3 The dose of intramuscular epinephrine is 0.01 mg/kg, up to a maximum of 0.5 mg in adults and 0.3 mg in children, and can be repeated every 5 to 15 min as needed. Intramuscular administration of epinephrine is preferred because of the rapid achievement of peak plasma levels with less of the cardiac risks of IV administration. The American Academy of Allergy, Asthma and Immunology practice parameter states, “Intravenous administration of epinephrine is also not recommended as first-line treatment of acute anaphylaxis, even in a medical setting, due to risk for cardiac adverse events such as arrhythmias and myocardial infarction.” This recommendation is based on an observational cohort study of 573 patients in an emergency department setting. Adverse cardiovascular events occurred with 3 of 30 doses of IV bolus epinephrine compared with 4 of 316 doses of intramuscular epinephrine (10% vs. 1.3%; odds ratio, 8.7 [95% CI, 1.8–40.7], P = 0.006).4 The American Academy of Allergy, Asthma and Immunology acknowledges that an IV epinephrine infusion may be used if there is an inadequate response to intramuscular dosing.3Anesthesiologists may believe that our practices fall outside the parameters outlined by the American Academy of Allergy, Asthma and Immunology. Many anesthesiologists, as noted by Tacquard et al., look to advanced cardiac life support algorithms in potentially life-threatening circumstances. In 2020, the American Heart Association (Dallas, Texas) also updated their Adult Basic and Advanced Life Support guidelines. Drawing primarily on the American Academy of Allergy, Asthma and Immunology practice parameter, the 2020 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care recommend intramuscular epinephrine 0.2 mg to 0.5 mg repeated 5 to 15 min as needed for anaphylaxis that has not progressed to cardiac arrest (class 1 recommendation). The American Heart Association guidelines recommend IV epinephrine, 0.05 mg to 0.1 mg boluses or as a continuous infusion as an alternative class 2a recommendation.5 These recommendations are based on level C evidence. In the absence of high-quality evidence, we suggest that anesthesiologists consider first-line treatment of perioperative anaphylaxis with intramuscular epinephrine injection to the anterolateral thigh at a dose of 0.01 mg/kg up to 0.5 mg for adults or up to 0.3 mg for children for rapid treatment with a reduced risk of cardiac adverse effects.Dr. Sweitzer receives funding from the International Anesthesia Research Society (Philadelphia, Pennsylvania) and UpToDate (Philadelphia, Pennsylvania) for editorial work. The other authors declare no competing interests.