From the Research
The mortality rate of untreated anaphylaxis is approximately 0.002 deaths/million person-years, and fatal anaphylaxis is very rare. Without prompt administration of epinephrine (adrenaline), which is the first-line treatment for anaphylaxis, the risk of death increases significantly 1. Epinephrine works rapidly to reverse the life-threatening symptoms of anaphylaxis by constricting blood vessels, increasing blood pressure, relaxing airway muscles to improve breathing, and reducing hives and swelling. For anyone experiencing anaphylaxis, immediate treatment with epinephrine is crucial - typically administered as 0.3-0.5 mg intramuscularly in the mid-outer thigh for adults or 0.15 mg for children under 30 kg.
Key Points to Consider
- Delayed administration of epinephrine is associated with increased mortality, with studies showing that most anaphylaxis-related deaths occur when epinephrine is either not given or given too late 2, 3, 4.
- Risk factors that increase mortality in untreated cases include pre-existing asthma, cardiovascular disease, and delayed recognition of symptoms.
- Anaphylaxis can progress rapidly from mild symptoms to cardiovascular collapse and death within minutes, which is why immediate intervention is essential.
- Approximately 98% of anaphylactic episodes respond to 2 or fewer doses of epinephrine, and biphasic reactions are uncommon (∼5%), and only extremely rarely lethal 1.
Recommendations
- Prompt administration of epinephrine is crucial in the treatment of anaphylaxis, and healthcare providers should be educated on the proper use of epinephrine autoinjectors and manual injection methods 5.
- Patients and caregivers should also be educated on the recognition and treatment of anaphylaxis, including the use of epinephrine autoinjectors.
- In cases where symptoms of severe anaphylaxis fail to resolve following an initial dose of epinephrine, a second dose may be administered, and emergency medical services (EMS) should be activated if necessary 4.