2001 DEY B9-508-00 7/01. Anaphylaxis: Screen, Educate, and Protect to Improve Patient Outcomes 2001...
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Transcript of 2001 DEY B9-508-00 7/01. Anaphylaxis: Screen, Educate, and Protect to Improve Patient Outcomes 2001...
2001 DEY B9-508-00 7/01
Anaphylaxis:
Screen, Educate, and Protect to Improve Patient Outcomes
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
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)
Pathogenesis of Anaphylaxis
• IgE-mediated (Type I hypersensitivity)
• Sensitization stage
• Subsequent anaphylactic response
Sensitization Stage
Antigen (allergen) exposure
Plasma cells produce IgE antibodies against the allergen
IgE antibodies attach to mast cells and basophils
Mast cell withfixed IgE antibodies
IgE
Granules containing histamine
Antigen
Plasma cell
Anaphylactic Reaction
More of same allergen invades body
Antigen
Mast cell granules release contents after antigen binds with IgE antibodies
Histamine and other mediators
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Allergen combines with IgE attached to mast cells and basophils, which triggers degranulation and release of histamine and other chemical mediators •
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Common Causes of IgE-mediated Anaphylaxis
• Foods• Insect venoms• Latex• Medications• Immunotherapy
– Insect venom– Inhalant allergens
Anaphylactoid Reactions
• Non–IgE-mediated
– Complement-mediated
• Anaphylatoxins, eg, blood products
– Direct stimulation
• eg, radiocontrast media
– Mechanism unknown
• Exercise
• NSAIDs
Myth: The Cause of Anaphylaxis is Always Obvious
REALITY:
• Idiopathic anaphylaxis is common
• Triggers may be hidden– Foods
– Latex
• Patient may not recall details of exposure, clinical course
Clinical Manifestations of Anaphylaxis
• Skin: Flushing, pruritus, urticaria, angioedema
• Upper respiratory: Congestion, rhinorrhea
• Lower respiratory: Bronchospasm, throat or
chest tightness, hoarseness, wheezing,
shortness of breath, cough
Clinical Manifestations of Anaphylaxis
• Gastrointestinal tract:
– Oral pruritus
– Cramps, nausea, vomiting, diarrhea
• Cardiovascular system:
– Tachycardia, bradycardia,
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
Myth: Anaphylaxis Always Presents with Cutaneous Manifestations
REALITY:• Approximately 10%-20% of anaphylaxis
cases will not present with hives or other cutaneous manifestations
• 80% of food-induced, fatal anaphylaxis cases were not associated with cutaneous signs or symptoms
Clinical Course of Anaphylaxis
• Uniphasic
• Biphasic
– Recurrence up to 8 hours later
• Protracted
– Hours to days
Myth: Prior Episodes Predict Future Reactions
REALITY:
• No predictable pattern
• Severity depends on:– Sensitivity of the individual – Dose of the allergen
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: Incidence
• 35%–55% of anaphylaxis is caused by food allergy
• 6%–8% of children have food allergy
• 1%–2% of adults have food allergy
• Incidence is increasing
• Accidental food exposures are
common and unpredictable
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
Food-induced Anaphylaxis: Common Symptoms
• Oropharynx: Oral pruritus, swelling of lips
and tongue, throat tightening
• GI: Crampy abdominal pain, nausea,
vomiting, diarrhea
• Cutaneous: Urticaria, angioedema
• Respiratory: Shortness of breath,
stridor, cough, wheezing
Food-induced Anaphylaxis: Fatal Reactions
• Fatal reactions are on the rise
– ~150 deaths per year
– Usually caused by a known allergy
• Patients at risk:
– Peanut and tree nut allergy
– Asthma
– Prior anaphylaxis
– Failure to treat promptly w/epinephrine
• Many cases exhibit biphasic reaction
Fatal Food-induced Anaphylaxis (Bock SA, et al. JACI 2001;107:191–193)
• 32 cases of fatal anaphylaxis
• Adolescents or young adults
• Peanuts, tree nuts caused >90% of Rxn
• 20 of 21 with complete history had asthma
• Most did not have epinephrine available
Food-induced Anaphylaxis: Prevention
• Learn to read product labels
– Identify alternative names for ingredients
– Find “hidden” ingredients
• Avoid high-risk foods (eg, baked goods)
• Avoid sharing food, utensils, or food containers
– Minute amounts can be life-threatening
• Provide educational materials
– FAAN- (www.foodallergy.org)
I. AVOID ALLERGENS
Food-induced Anaphylaxis: Prevention
• Complete avoidance is impossible
• Must always be prepared to treat a reaction
– Have an emergency action plan
– Keep EpiPen or EpiPen Jr on hand at all times
– Train caregivers and teachers on EpiPen use
– Wear MedicAlert bracelet
II. RISK MANAGEMENT
Venom-induced Anaphylaxis: Incidence
• 0.5%–5% (13 million) Americans are
sensitive to one or more insect venoms • Incidence is underestimated• Incidence increasing due to fire ants and
Africanized bees• Incidence rising due to more outdoor activities• At least 40–100 deaths per year
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
Venom-induced Reactions: Common Symptoms
• Normal: Local pain, erythema, mild swelling
• Large local: Extended swelling, erythema• Anaphylaxis: Usual onset within 15–20 minutes
– Cutaneous: urticaria, flushing, angioedema
– Respiratory: dyspnea, stridor
– Cardiovascular: hypotension, dizziness, loss of consciousness
• 30%–60% of patients will experience a systemic reaction with subsequent stings
Venom-induced Anaphylaxis: Prevention
Avoidance Measures
What to do What not to doHave professionals Use scented productsremove hives or nests
Wear bright colorsWear white, smooth- finish clothes, ankle- Go barefoothigh shoes
Drink from open cansKeep outdoor areas free when contents are notof garbage visible
Venom-induced Anaphylaxis: Prevention
Risk Management
• Keep EpiPen or EpiPen Jr on hand at all times
• Educate and train on EpiPen use
• Develop emergency action plan
• Wear a MedicAlert bracelet• Consult an allergist to determine need for venom
immunotherapy
Venom-induced Anaphylaxis: Immunotherapy
• Medical criteria– Hx of any systemic reaction in adults– Hx of life-threatening reaction in children– Positive venom skin test
• 97% effective• Can be discontinued in most after 3–5 years;
10% risk of systemic reaction to subsequent stings
Venom-induced Anaphylaxis: Immunotherapy
• Risk of anaphylaxis– 10%-15% of patients experience
systemic reactions during early weeks of treatment
– Sx generally occur within 20 minutes
– Patients at risk: asthma, prior reactions, beta blocker or ACEI therapy
Immunotherapy-induced Anaphylaxis
• Risk management
– Trained physician, equipped facility
– Epinephrine immediately available
– Monitor closely for 20–30 minutes – Consider supply of EpiPen for those at
high risk
Latex-induced Anaphylaxis: Incidence
• 1%–6% of US population (up to 16 million)
affected
• 8%–17% incidence among health care workers
• Repeated exposure leads to a higher risk
• Incidence has increased since mid 1980s
– Latex gloves, especially powdered gloves
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
Reactions to Latex
• Irritant contact dermatitis
– Dry, itchy, irritated hands
• Allergic contact dermatitis
– Delayed hypersensitivity
• Latex allergy
– Immediate hypersensitivity
– Sx: hives, itching, sneezing, rhinitis, dyspnea, cough,
wheezing
– Greatest risk with mucosal contact
Latex-induced Anaphylaxis: Prevention
• Use latex-free products
• Alert employer/health care providers, schools about need for latex-free products and equipment
• Wear MedicAlert bracelet
• Awareness of cross-sensitivity with foods:
I. AVOIDANCE
– Banana– Avocado– Chestnuts
– Kiwi– Stone fruit– Others
Latex-induced Anaphylaxis: Prevention
• Prescribe EpiPen® or EpiPen® Jr
– Accidental exposure
– Patients at risk• Educate re: EpiPen® use• Develop emergency action plan
II. RISK MANAGEMENT
Other Causes of Anaphylacticand Anaphylactoid Reactions
• Drugs
– Antibiotics
– Chemotherapeutic agents
– Aspirin, NSAIDs
– Biologicals (vaccines, monoclonal antibodies)
• Radiocontrast media
• Exercise
• Idiopathic
Diagnosing Anaphylaxis
• Based on clinical presentation, exposure Hx
• Cutaneous, respiratory Sx most common
• Some cases may be difficult to diagnose
– Vasovagal syncope
– Scombroid poisoning
– Systemic mastocytosis
Diagnosing Anaphylaxis
• Careful history to identify possible causes
• Can be confirmed by serum tryptase
– Specific for mast cell degranulation
– Remains elevated for up to 6 hours
• Other labs to rule out other diagnoses
• Refer to allergist for specific testing
Diagnosing Anaphylaxis
• Skin tests/RAST– Foods– Insect venoms– Drugs
• Challenge tests– Foods– NSAIDs– Exercise
Allergists can identify specific causes by:
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
EpiPen/EpiPen Jr: Directions for Use
EpiPen/EpiPen Jr: Directions for Use
EpiPen/EpiPen Jr: Directions for Use
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
Treatment of Anaphylaxis
• Additional measures may include
– Corticosteroids
– Supplemental O2; airway maintenance
– IV fluids, vasopressor therapy
– Repeat epinephrine if Sx persist or increase after 10-15 minutes
– Repeat antihistamine ± H2 blocker if Sx persist
– Observe for a minimum 4 hours
– Arrange follow-up care, provide EpiPen® Rx and education
Myth: Anaphylaxis is Reported
REALITY:
• Most individuals do not inform their personal
physician of an anaphylactic reaction either at
the time of the reaction or during routine exams
Risk Management for Anaphylaxis
• SCREEN
– Atopy
• 10% of children with asthma have food
allergy• 30%–40% of children with atopic dermatitis
have food allergy
– Previous reactions
• 75% will have more than one
• 57% will have three or more
Screening Patients at Risk
Did you ever have a severe allergic reaction:
– To any food?
– To any medicine?
– To an insect sting?
– To latex?
– That caused breathing trouble? Severe hives and
swelling? Severe vomiting or diarrhea? Dizziness?
– That required you to go to the hospital?
SCREEN, Educate, and ProtectPatients at Risk
Risk Management for Anaphylaxis
• EDUCATE
– Teach avoidance measures
– “Accidents are never planned”
– Stress importance of:
• Always having a current EpiPen on hand
• Immediate treatment
– Emphasize the need for follow-up care
EpiPen® 2-Pak
* EpiPen® 2-Pak was launched in April 2001
Risk Management for Anaphylaxis
• EDUCATE: Draft an Emergency Plan
– Provide specific instructions on when to
administer EpiPen or EpiPen Jr
– Call for help (911); transport patient to emergency
care facility
– Stay calm; keep patient warm
– Specify directions for antihistamine use
– Report EpiPen administration
Screen, Educate, and Protect
AAAAI Board of Directors. Position statement: Anaphylaxis in schools and other childcare settings. J Allergy Clin Immunol 1999;102:173-176. Reprinted with permission.
Emergency Health Care PlanALLERGY TO:_____________________________________________________________
Child’sName:___________________________D.O.B:____________Teacher:___________________
Asthmatic Yes (High risk for severe reaction) No
Signs of an allergic reaction include:
Systems: Symptoms:
•MOUTH itching & swelling of the lips, tongue, or mouth
•THROAT* itching and/or a sense of tightness in the throat, hoarseness, and hacking cough
•SKIN hives, itchy rash, and/or swelling about the face or extremities
•GUT nausea, abdominal cramps, vomiting, and/or diarrhea
•LUNG* shortness of breath, repetitive coughing, and/or wheezing
•HEART* “thready” pulse, “passing-out”
The severity of symptoms can quickly change! *All above symptoms can potentially progress to a life-threatening situation!
ACTION:
1. If ingestion is suspected give________________________________________________ medication/dose/route
and_____________________________________________________immediately! 2. CALL RESCUE SQUAD:_________________________________________________
3. CALL: Mother__________________ Father___________________ or emergency contacts
4. CALL: Dr.____________________________ at ____________________________DO NOT HESITATE TO ADMINISTER MEDICATION OR CALL RESCUE SQUAD
EVEN IF PARENTS OR DOCTOR CANNOT BE REACHED!
________________________ _______ _______________________M.D. _______ Parent Signature Date Doctor’s Signature Date
For children with multiple food allergies, use one form for each food.
Emergency Health Care PlanALLERGY TO:_____________________________________________________________
Child’sName:___________________________D.O.B:____________Teacher:___________________
Asthmatic Yes (High risk for severe reaction) No
Signs of an allergic reaction include:
Systems: Symptoms:
•MOUTH itching & swelling of the lips, tongue, or mouth
•THROAT* itching and/or a sense of tightness in the throat, hoarseness, and hacking cough
•SKIN hives, itchy rash, and/or swelling about the face or extremities
•GUT nausea, abdominal cramps, vomiting, and/or diarrhea
•LUNG* shortness of breath, repetitive coughing, and/or wheezing
•HEART* “thready” pulse, “passing-out”
The severity of symptoms can quickly change! *All above symptoms can potentially progress to a life-threatening situation!
ACTION:
1. If ingestion is suspected give________________________________________________ medication/dose/route
and_____________________________________________________immediately! 2. CALL RESCUE SQUAD:_________________________________________________
3. CALL: Mother__________________ Father___________________ or emergency contacts
4. CALL: Dr.____________________________ at ____________________________DO NOT HESITATE TO ADMINISTER MEDICATION OR CALL RESCUE SQUAD
EVEN IF PARENTS OR DOCTOR CANNOT BE REACHED!
________________________ _______ _______________________M.D. _______ Parent Signature Date Doctor’s Signature Date
For children with multiple food allergies, use one form for each food.
EMERGENCY CONTACTS TRAINED STAFF MEMBERS
1.__________________________________
Relation:________________Phone:________
1._________________________Room______
2.__________________________________
Relation:________________Phone:________
2._________________________Room______
3.__________________________________
Relation:________________Phone:________
3._________________________Room______
PlaceChild’sPictureHere
Myth: Anaphylaxis is Easy to Avoid If You Know What You are Allergic To
REALITY:
• Most cases of anaphylaxis are due to accidental exposures
Risk Management for Anaphylaxis
• PROTECT:
– Prescribe self-injectable EpiPen
– Teach patient proper use of EpiPen
– Educate family, friends, teachers, caregivers
Anaphylaxis
Screen, educate, and protect
+
Immediate treatment
=
Saved lives