What is the initial management of anaphylaxis in the emergency room?

From the Guidelines

The initial management of anaphylaxis in the emergency room requires immediate administration of epinephrine (adrenaline) 0.01 mg/kg of 1 mg/mL (1:1000) solution, up to 0.5 mg in adults and 0.3 mg in children, intramuscularly in the anterolateral thigh, which should be repeated every 5 to 15 minutes if symptoms persist, as recommended by the most recent guidelines 1.

Key Considerations

• The dose of epinephrine is crucial, and it should be administered intramuscularly into the vastus lateralis (antero-lateral thigh) 1.
• Additional emergency management includes placing the patient in a supine position if their presentation is mainly cardiovascular, monitoring vital signs, and administration of oxygen to patients with respiratory distress and those receiving further doses of epinephrine 1.
• Intravenous fluids, such as normal saline, should be administered early with the first epinephrine dose to patients with cardiovascular involvement and should be repeated if lack of response 1.
• Patients with lower respiratory symptoms should receive inhaled beta-2 agonists following initial treatment with epinephrine 1.

Adjunctive Therapy

• Antihistamines and glucocorticoids are often used as adjunctive therapy for cutaneous signs and symptoms associated with anaphylaxis, but they should not be administered before, or in place of, epinephrine 1.
• Biphasic anaphylaxis is a recurrence of anaphylaxis after appropriate treatment, and extended clinical observation is suggested in a setting capable of managing anaphylaxis for patients with resolved severe anaphylaxis and/or those who need more than one dose of epinephrine 1.

Monitoring and Follow-up

• Continuous monitoring of vital signs, cardiac rhythm, oxygen saturation, and end-tidal CO2 is essential in the management of anaphylaxis 1.
• Patients should be educated about the signs and symptoms of anaphylaxis, and an emergency action plan that includes instructions for using epinephrine should be reviewed with patients on allergen immunotherapy 1.

From the FDA Drug Label

Adults and Children 30 kg (66 lbs) or more: 0.3 to 0.5 mg (0.3 to 0.5 mL) intramuscularly or subcutaneously into anterolateral aspect of the thigh every 5 to 10 minutes as necessary Children 30 kg (66 lbs) or less: 0.01 mg/kg (0.01 mL/kg), up to 0.3 mg (0.3 mL), intramuscularly or subcutaneously into anterolateral aspect of the thigh every 5 to 10 minutes as necessary

The initial management of anaphylaxis in the emergency room involves administering epinephrine (IM). The dosage is as follows:

• Adults and children over 30 kg: 0.3 to 0.5 mg every 5 to 10 minutes as necessary
• Children under 30 kg: 0.01 mg/kg (up to 0.3 mg) every 5 to 10 minutes as necessary 2

From the Research

Initial Management of Anaphylaxis in the Emergency Room

The initial management of anaphylaxis in the emergency room involves several key steps:

• Administering epinephrine (adrenaline) as the first-line treatment, which is universally recommended for the treatment of anaphylaxis 3, 4, 5, 6
• Injecting epinephrine intramuscularly in the anterolateral aspect of the mid-thigh, with an initial recommended adult dose of 0.3-0.5 mg 3, 4, 6
• Providing supplemental oxygen and aggressive fluid resuscitation to treat intravascular volume depletion 4
• Using antihistamines and corticosteroids as second-line or third-line medications, but never delaying the administration of epinephrine 4, 5, 7

Key Considerations

• Prompt recognition and treatment of anaphylaxis are critical to prevent morbidity and mortality 4, 5, 6
• Delays in administering epinephrine can increase the risk of adverse outcomes 3, 4, 6
• The use of corticosteroids in the emergency management of anaphylaxis may be beneficial, but there is no compelling evidence to support or oppose their use 7

Treatment Approach

• A working definition of anaphylaxis for emergency medicine providers is: "Anaphylaxis is a serious reaction causing a combination of characteristic findings, and which is rapid in onset and may cause death" 6
• The treatment approach should be individualized, with consideration of the patient's symptoms, medical history, and response to treatment 4, 5
• Novel epinephrine formulations, such as autoinjectors, are being developed to improve the safety and ease of use of epinephrine administration 3