2001 DEY B9-508-00 7/01

Definition of Anaphylaxis

• Systemic allergic reaction

– Affects body as a whole

– Multiple organ systems may be involved

• Onset generally acute

• Manifestations vary from mild to fatal

– Recurrence up to 8 hours later

– Protracted

– Hours to days

Signs and Symptoms of Anaphylaxis

• Skin: Flushing, Itching, swelling, hives• Lower respiratory: Bronchospasm, throat or

chest tightness, hoarseness, wheezing, shortness of breath, cough

• Gastrointestinal tract:– Oral itching – Cramps, nausea, vomiting, diarrhea

• Cardiovascular system:– Increased ht rate then lower heart rrate,

hypotension/shock, arrhythmias, ischemia, chest pain

Clinical Manifestations of Anaphylaxis

Signs/symptoms Incidence (%)

Urticaria and angioedemaUpper airway edema*Dyspnea and wheezingFlush*Dizziness, syncope, and hypotensionGastrointestinal symptomsRhinitis*Headache*Substernal pain*Itch without rash*Seizure*

*Symptom or sign not reported in all four series

8856474633301615

64.5

1.5

Anaphylaxis Fatalities

• Estimated 500–1000 deaths annually• 1% risk • Risk factors:– Failure to administer epinephrine

immediately – Beta blocker, ?ACEI therapy– Asthma– Cardiac disease– Rapid IV allergen

Food-induced Anaphylaxis: Common Triggers

• Children and adults (usually not outgrown): – Peanuts– Tree nuts– Shellfish– Fish

• Additional triggers in children (commonly outgrown):– Milk– Egg– Soy– Wheat

Latex-induced Anaphylaxis: Triggers

• Proteins in natural rubber latex

• Component of ~40,000 commonly used items

– Rubber bands

– Elastic (undergarments)

– Hospital and dental equipment

• Latex-dipped products are biggest culprits

– Balloons, gloves, bandages, hot water bottles

Venom-induced Anaphylaxis: Common Culprits

• Hymenoptera– Bees – Wasps– Yellow jackets– Hornets– Fire ants

• Geographical– Honeybees, yellow jackets most common in East,

Midwest, and West regions of US– Wasps, fire ants most common in Southwest

and Gulf Coast

Other Causes of Anaphylacticand Anaphylactoid Reactions

• Drugs

– Antibiotics

– Chemotherapeutic agents

– Aspirin, NSAIDs

– Biologicals (vaccines, monoclonal antibodies)

• Radiocontrast media

• Exercise

• Idiopathic

Myth: If you have been stung by a bee or eaten a peanut and have not reacted to it then you do not have Anaphylaxis

• IgE-mediated (Type I hypersensitivity)

• Sensitization stage

• Subsequent anaphylactic response

Myth: Anaphylaxis Is Rare

REALITY:

• Anaphylaxis is underreported

• Incidence seems to be increasing

• Up to 41 million Americans at risk (Neugut AI et al, 2001)

• 63,000 new cases per year (Yocum MW et al, 1999)

• 5% of adults may have a history of anaphylaxis (various surveys)

Myth: The Cause of Anaphylaxis is Always Obvious

REALITY:

• Idiopathic anaphylaxis is common

• Triggers may be hidden

• Patient may not recall details of exposure, clinical course

Myth: Prior Episodes Predict Future Reactions

REALITY:

• No predictable pattern

• Severity depends on:– Sensitivity of the individual – Dose of the allergen

Myth: Anaphylaxis is Easy to Avoid If You Know What You are Allergic To

REALITY:

• Most cases of anaphylaxis are due to accidental exposures

Treatment of Anaphylaxis

• Immediate treatment with epinephrine imperative– No contraindications in anaphylaxis– Failure or delay associated with fatalities– IM may produce more rapid, higher peak levels

vs SC– Must be available at all times

• Antihistamine (oral or parenteral; if oral, use liquid or chewable tablet)

• Call 911; proceed to Emergency Room

Myth: Epinephrine is Dangerous

REALITY:

• Risks of anaphylaxis far outweigh risks of epinephrine administration

• Minimal cardiovascular effects in children (Simons et al, 1998)

• Caution when administering epinephrine in elderly patients or those with known cardiac disease

EpiPen® 2-Pak

Call for help (911); transport patient to

emergency care facility

Stay calm;

Keep patient warm

How to use an epipen.

Risk Management for Anaphylaxis

• Be aware of the problem and keep your “index

of suspicion” high.

• The school nurse will

– EDUCATE: the student

– Draft an Emergency Plan

– In form staff of KNOWN anaphylactic

students and STAFF