Dealing with a patient suffering from acute anaphylaxis attack can be a frightening and challenging experience for even the most seasoned emergency clinician. The following 10 pearls and pitfalls on management of anaphylaxis was taken from an editorial published in the Southern Medical Journal by Dr Richard D deShazo. This short brilliant article gives you the Top 10 things not to miss the next time you encounter a patient suffering from anaphylaxis.
Top 10 pearls for managing anaphylaxis
- The progression of anaphylaxis from itching to urticaria to death is unpredictable. Patients with these symptoms should be treated as soon as they occur.
- Patients with anaphylaxis may present with hypotension alone and no cutaneous or pulmonary findings. Acute diarrhoea can also be an isolated finding.
- Adrenaline is the first line and most important drug used in an acute allergic reaction. Antihistamines and corticosteroids are second line therapy.
- Adrenaline should be administered IM, not subcutaneously. It should not be administered IV in concentrations of greater than 1:10,000, and then only in dire straits.
- There is no absolute contraindication to the use of adrenaline in patients with heart disease who experience anaphylaxis.
- Anaphylaxis reactions are biphasic as often as 20% of the time. That is, symptoms recur an average of 4 to 8 hours after the original episode, even with adequate treatment. Reports of earlier recurrence or later recurrence have been documented. Short term admission is warranted, and appropriated discharge with an adrenaline autoinjector device is warranted.
- At least 40% of patients who have allergic reactions after insect stings will have equally severe or worse reactions on re-sting. Therefore, all patients who have anaphylaxis after an insect sting or any unknown or potentially unavoidable cause (eg,peanuts) should be prescribed an adrenaline autoinjector device, and referred to allergist for testing and consideration of immunotherapy. This treatment is over 95% effective for preventing allergic reactions on re-sting.
- Patients on beta blockers who experience anaphylaxis may have a hypertensive response to adrenaline and suboptimal clinical improvement, and may require 1 to 3mg of IV glucagon once or glucagon by continuous infusion until anaphylaxis is controlled. IV glucagon makes most people vomit and one must prepare for that when using it.
- Rarely, anaphylactic reactions can be protracted over many hours. In such cases, patients may require large volume fluid resuscitation, treatment with vasopressors, or intra-aortic ballon pump therapy. Risk factors for this syndrome are unknown.
- The serum tryptase assay is highly specific for anaphylaxis and can be used retrospectively to confirm the diagnosis where it was unclear. However, a negative result does not exclude the diagnosis when clinical manifestations are compelling.
- deShazo, R. (2007). Anaphylaxis: My “Top 10” List. Southern Medical Journal. 100(3), 233-234. (full text)