Usually comes on in minutes / Peaks in 15-30 minutes
Sensation of warmth
Intense itching of soles of feet and palms of hands
Breathing difficulties
Tightness and swelling in throat
Coughing, sneezing, wheezing
Tightness in chest
Characteristics of Anaphylaxis #2
Increased pulse rate
Swollen face, tongue, mouth
Nausea and vomiting
Dizziness
Blue around lips and mouth
Anaphylaxis: What To Do
Check ABC’s
Use ice pack on bee sting
Inject epinephrine (dilates bronchioles)
(hopefully victim will have some)
Inject in outside part of thigh, hold for 10 seconds
May need to repeat
Get help immediately - 911(float trip)
Benedryl – too slow for major emergency, but worth a try
Simons, F. E. R. et al. N Engl J Med 1994;330:1663-1670 Chemical Structure of Histamine and Representative H1-Receptor-Antagonist Drugs
Figure 1. Chemical Structure of Histamine and Representative H1-Receptor-Antagonist Drugs. For practical purposes, H1 antagonists are now often divided into first-generation, relatively sedating medications and second-generation, relatively nonsedating medications. The latter group includes most H1 antagonists introduced since 1981, of which terfenadine, astemizole, loratadine, and cetirizine are the best known. Some second-generation H1 antagonists do not fit readily into any of the traditional classes: alkylamines (e.g., chlorpheniramine), ethanolamines (e.g., diphenhydramine), piperazines (e.g., hydroxyzine), piperidines, ethylenediamines, and phenothiazines. For example, although terfenadine, astemizole, loratadine, ketotifen, and levocabastine all contain a piperidine ring, they have diverse chemical structures1,2. Cetirizine, ketotifen, and azelastine are not approved for use in the United States at this time.
Dealing With Anaphylaxis
Give EPIPEN.
Remove grey cap from end.
Press EPIPEN firmly into side of thigh until a click is heard, then hold in place and count to 10.
Administer Benadryl (for breathing difficulties).
Call 911 (emergency) to transport to hospital.
Notify parents immediately after emergency call.
Frequency of symptoms in Anaphylaxis
Simons, F. E. R. et al. N Engl J Med 1994;330:1663-1670 Formulations and Dosages of Representative H1-Receptor Antagonists
Table 2. Formulations and Dosages of Representative H1-Receptor Antagonists.
Anaphylaxis
Onset of symptoms of anaphylaxis: usually in 5 to 30 minutes; can be hours later
A more prolonged latent period has been thought to be associated with a more benign course.
Mortality: due to respiratory events (70%), cardiovascular events (24%)
Prevention of anaphylaxis
Avoid the responsible allergen (e.g. food, drug, latex, etc.).
Keep an adrenaline kit (e.g. Epipen) and Benadryl on hand at all times.
Medic Alert bracelets should be worn.
Venom immunotherapy is highly effective in protecting insect-allergic individuals.
Treatment of anaphylaxis
EPINEPHRINE (1:1000) SC or IM - 0.01 mg/kg (maximal dose 0.3-0.5 ml) - administer in a proximal extremity - may repeat every 10-15 min, p.r.n.
EPINEPHRINE intravenously (IV) - used for anaphylactic shock not responding to therapy - monitor for cardiac arrhythmias
EPINEPHRINE via endotracheal tube
Treatment of anaphylaxis
Place patient in Trendelenburg position.
Establish and maintain airway.
Give oxygen via nasal cannula as needed.
Place a tourniquet above the reaction site (insect sting or injection site).
Epinephrine (1:1000) 0.1-0.3 ml at the site of antigen injection
Start IV with normal saline.
Treatment of anaphylaxis
Benadryl (diphenhydramine) - H1 antagonist
Tagamet (cimetidine) - H2 antagonist
Corticosteroid therapy: hydrocortisone IV or prednisone po
Treatment of anaphylaxis
Biphasic courses in some cases of anaphylaxis: - Recurrence of symptoms: 1-8 hrs later - In those with severe anaphylaxis, observe for 6 hours or longer. - In milder cases, treat with prednisone; Benadryl every 4 to 6 hours; advise to return immediately for recurrent symptoms
Treatment of Anaphylaxis in Beta Blocked Patients
Give epinephrine initially.
If patient does not respond to epinephrine and other usual therapy: - Isoproterenol (a pure beta-agonist) 1 mg in 500 ml D5W starting at 0.1 mcg/kg/min - Glucagon 1 mg IV over 2 minutes
Use of epinephrine in Food Allergy
Epinephrine should be used immediately after accidental ingestion of foods that have caused anaphylactic reactions in the past.
An individual who is allergic to peanut, nuts**, shellfish, and fish should immediately take epinephrine if they consume one of these foods.
A mild allergic reaction to other foods (e.g. minor hives,vomiting) may be treated with an antihistamine
Immediate Hypersensitivity
Acute (type I) hypersensitivities begin in seconds after contact with allergen
Anaphylaxis – initial allergen contact is asymptomatic but sensitizes the person
Subsequent exposures to allergen cause:
Release of histamine and inflammatory chemicals
Systemic or local responses
Immediate Hypersensitivity
The mechanism involves IL-4 secreted by T cells
IL-4 stimulates B cells to produce IgE
IgE binds to mast cells and basophils causing them to degranulate, resulting in a flood of histamine release and inducing the inflammatory response
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