World Allergy Organization Guidelines for the Assessment and Management of Anaphylaxis

Abstract

Abstract:The illustrated World Allergy Organization (WAO) Anaphylaxis Guidelines were created in response to absence of global guidelines for anaphylaxis. Uniquely, before they were developed, lack of worldwide availability of essentials for the diagnosis and treatment of anaphylaxis was documented. They incorporate contributions from more than 100 allergy/immunology specialists on 6 continents. Recommendations are based on the best evidence available, supported by references published to the end of December 2010. The Guidelines review patient risk factors for severe or fatal anaphylaxis, co-factors that amplify anaphylaxis, and anaphylaxis in vulnerable patients, including pregnant women, infants, the elderly, and those with cardiovascular disease. They focus on the supreme importance of making a prompt clinical diagnosis and on the basic initial treatment that is urgently needed and should be possible even in a low resource environment. This involves having a written emergency protocol and rehearsing it regularly; then, as soon as anaphylaxis is diagnosed, promptly and simultaneously calling for help, injecting epinephrine (adrenaline) intramuscularly, and placing the patient on the back or in a position of comfort with the lower extremities elevated. When indicated, additional critically important steps include administering supplemental oxygen and maintaining the airway, establishing intravenous access and giving fluid resuscitation, and initiating cardiopulmonary resuscitation with continuous chest compressions. Vital signs and cardiorespiratory status should be monitored frequently and regularly (preferably, continuously). The Guidelines briefly review management of anaphylaxis refractory to basic initial treatment. They also emphasize preparation of the patient for self-treatment of anaphylaxis recurrences in the community, confirmation of anaphylaxis triggers, and prevention of recurrences through trigger avoidance and immunomodulation. Novel strategies for dissemination and implementation are summarized. A global agenda for anaphylaxis research is proposed.

Drug‐induced anaphylaxis in the emergency room

“…4). 1, 31, 32, 33 Early injection of adrenaline for anaphylaxis, defined as injection before ER arrival, can significantly reduce the likelihood of hospital admission, as compared with initial injection after arrival at the ER 34. Although no human studies regarding the timing of treatment for anaphylaxis could be found, analysis of 92 deaths related to anaphylaxis showed that adrenaline was given prior to cardiac arrest in only 22 of the cases (24%) 35.…”

“…Most international anaphylaxis guidelines recommend injection of adrenaline by the intramuscular route in the mid‐anterolateral thigh at a dose of 0.01 mg/kg of a 1:1,000 (1 mg/mL) solution, up to a maximum of 0.5 mg in adults (0.3 mg in children). Depending on the severity of the episode and the response to the initial injection, the dose can be repeated every 5–15 min, as required 1, 31, 33, 36. Intravenous adrenaline is an option in patients with severe hypotension or cardiac arrest unresponsive to intramuscular doses of adrenaline and fluid resuscitation 1.…”

“…However, serious adverse effects, such as ventricular arrhythmias, hypertensive crisis, and pulmonary edema can potentially occur after i.v. administration of an overdose of adrenaline 31. A recent study showed that the risks of overdose and adverse cardiovascular events were significantly higher with i.v.…”

“…International guidelines concur that H1 and H2 antihistamines and glucocorticoids are second‐line31 and even third line33 treatments for anaphylaxis. These medications are not life‐saving and should not be used as initial or sole treatment.…”

“…Skin tests, which involve exposure of the mast cells in the skin of patients who experience anaphylaxis to the suspected allergen, remain the gold standard for detection of IgE‐mediated reactions 27. The optimal time for testing is generally considered to be 3–4 weeks after an acute anaphylactic episode 31. The allergist undertaking the relevant tests must be experienced in the management of drug allergies 26.…”