7/25/2016. Use of Epinephrine in the Community. Knowledge Amongst Paramedics. Knowledge Amongst Paramedics survey of 3479 paramedics

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1 Recognition & Management of Anaphylaxis in the Community S. Shahzad Mustafa, MD, FAAAAI Disclosures Speaker s bureau Genentech, Teva Consultant Genentech, Teva Outline Knowledge gap Definition Pathophysiology Common causes Recognition and management 1

2 Use of Epinephrine in the Community Simons. JACI 2009; 124(2): 301., Wood. JACI 2014; 133(2): 461. Knowledge Amongst Paramedics 2010 survey of 3479 paramedics Question Yes No Are you confident you can recognize a patient 3410 (98%) 69 (2%) experiencing anaphylaxis? Are you confident in your ability to manage a patient 3379 (97.1%) 100 (2.9%) in anaphylaxis? Are you comfortable administering epinephrine to a patient not in cardiac arrest? 3351 (96.3%) 128 (3.7%) Jacobsen. PreHosp Emer Care 2012; 16(4): 527. Knowledge Amongst Paramedics Recognition of Anaphylaxis Correct Incorrect Classic presentation 3244 (98.9%) 36 (1.1%) Atypical presentation 87 (2.9%) 2871 (97.1%) What is the immediate, initial treatment of anaphylaxis? Epinephrine 46.2 % Diphenhydramine 40.1% IV fluids 7.7% Short acting bronchodilator 5.6% Corticosteroids 0.3% Don t know the answer 0.2% Jacobsen. PreHosp Emer Care 2012; 16(4):

3 Knowledge Amongst Paramedics What route should you administer epinephrine? Subcutaneous 58.4% Intramuscular 38.9% Intravenous 1.7% Sublingual 0.7% Nebulized/aerosolized 0.1% Don t know the answer 0.2% What location would you administer epinephrine? Deltoid 60.5% Thigh 11.6% Deltoid or thigh 3.8% Abdomen 2.0% Other 22.1% Jacobsen. PreHosp Emer Care 2012; 16(4): 527. Knowledge Amongst Paramedics Are there contraindications to giving epinephrine to a patient experiencing anaphylactic shock? Yes 36.2% No 63.8% Jacobsen. PreHosp Emer Care 2012; 16(4): 527. Epinephrine Use in the Emer. Dept. Sclar. Amer J of Med 2014; 127: S1. 3

4 Definition Acute, potentially life-threatening systemic/multi-organ reaction that is immunologically mediated and occurs after the likely exposure to an allergen Clinical diagnosis Very little if any role for acute diagnostic testing Consider allergy/immunology evaluation for long term management Brown. Middleton s Allergy Principle and Practice 8 th Edition. Chapter Sensitization Antigen (allergen) exposure Antigen Plasma cells produce IgE antibodies against the allergen IgE antibodies attach to mast cells and basophils IgE Plasma cell Mast cell with fixed IgE antibodies Granules containing histamine Allergic Reaction More of same allergen invades body Allergen combines with IgE attached to mast cells and basophils, which triggers degranulation and release of histamine and other chemical mediators. Antigen Mast cell granules release contents after antigen binds with IgE antibodies Histamine and other mediators 4

5 Mast Cell Degranulation Orr. TSC in Slide Atlas of Immunology; Roitt et al,, ed IgE Mediated & Non-IgE Mediated Reactions IgE Mediated Foods Stinging insects Medications Penicillin Sulfa NSAIDs Latex Immunotherapy Aeroallergens Stinging insects Non-IgE Mediated Radio-contrast material Acute viral infections Medications Narcotics Vancomycin NSAIDs Scromboid poisoning Idiopathic IgE Versus Non-IgE Mediated Reactions 5

6 Common Food Allergens Pediatrics Food % Cow s milk 2.5 Egg white 1.5 Peanut 1.0 Tree nuts 0.5 Wheat 0.4 Soy 0.4 Shellfish 0.1 Finned fish 0.1 Sesame 0.1* Adults Food % Peanut 0.6 Tree nuts 0.6 Shellfish 2.0 Finned fish 0.4 Sesame 0.1* Boyce. JACI 2010; 126: Stinging Insects Yellow jacket Yellow hornet White-faced hornet Honeybee Wasp Fire ant Allergen Immunotherapy Subcutaneous immunotherapy 0.1% risk of systemic reaction 1 per 1 million doses result in grade 3/4 systemic reaction 1 confirmed death since 2008 Sublingual immunotherapy Case reports only (~6) No fatality reported despite more than 1 billion doses administered 6

7 Penicillin Allergy Most commonly reported medication allergy > 90% of PCN allergic individuals can safely tolerate penicillins and related antibiotics Public health implications Patients being treated with alternative antibiotic regimens are not reflective of the standard of care Increased risk of complications Increased length of inpatient hospitalization Increased cost of care CDC with a major focus on antibiotic stewardship PCN Skin Testing Penicillin Allergy In PCN allergic individuals: 50% experience resolution of allergy at 5 years 80% at 10 years 95%+ with a remote history 10% of individuals experience a delayed, maculopapular rash with amoxicillin Nearly 100% of individuals with EBV will experience a rash if exposed to PCN Blanca. JACI 1999; 103:

8 Viral Exanthem versus Urticaria PCN Allergy Diagnostic Testing Major determinant: BPO (benzyl penicilloyl) Minor determinants: penicilloate, penilloate, PCN G Well studied and validated skin test reagents NPV nearly 100% for anaphylaxis NPV roughly 97% for IgE mediated allergy PPV roughly 60% Skin testing provides results within one hour No role for in vitro IgE testing or ELISA Latex Allergy Incidence increased in the 1980s but has sharply declined with the use of latex-free materials Risk factor for sensitization is frequent exposure Individuals with chronic bladder conditions Health care workers Important to distinguish between IgE mediated reactions versus irritant reactions or contact dermatitis Diagnosis No validated skin test reagents Test of choice is in vitro latex specific IgE 8

9 Management Lieberman P. JACI 2010; 126(3): 477. Signs and Symptoms Common complaints NOT suggestive of an IgE mediated mechanism Isolated rhinitis Isolated cough/asthma Chronic abdominal discomfort Isolated GERD Chronic urticaria Fatigue Reactions occur inconsistently Reactions occur only with larger doses Ongoing mild to moderate atopic dermatitis Frequency of Organ System Involvement Wood. JACI 2014; 133:

10 Cardiovascular Effects Pumphrey. Clin Exp All 2003; 30(8): Management Secure airway Epinephrine is the 1 st line and only FDA approved therapy Antihistamines act as an adjunctive therapy mostly aimed at dermatologic manifestations Systemic steroids decrease the risk of biphasic or protracted reactions Mediators of Anaphylaxis Leukotrienes Prostaglandins Kinins Platelet activating factor Interleukins Tumor necrosis factor Histamine Antihistamines (diphenhydramine) 10

11 Management Epinephrine 1 -adrenergic receptor 2 -adrenergic receptor 1 -adrenergic receptor 2 -adrenergic receptor Vasoconstriction Peripheral vascular resistance Mucosal edema Insulin release Inotropy Chronotropy Bronchodilation Vasodilation Glycogenolysis Mediator release Simons. Curr Opin All Clin Immunol 2010; 10: 354. Management Epinephrine Antihistamines Simons. JACI 1998; 101: 33. Jones. Ann All Asth Immunol 2008; 100(5): 458. Medications X Brown. Middleton s Allergy Principle and Practice 8 th Edition. Chapter

12 Risk Factors for Poor Outcomes in Anaphylaxis Adolescent patients History of previous anaphylaxis History of peanut and/or tree nut allergy History of sub-optimally controlled asthma Delayed or lack of epinephrine administration Epinephrine is exceedingly safe and there have been few if any reports in the literature implicating epinephrine with significant adverse effects when used appropriately. Points to Consider Previous reactions do NOT predict the severity of future reactions No diagnostic tools to predict the severity of reactions Absolute contraindication to epinephrine: None! Relative contraindication to epinephrine: None! Comorbidities to be aware of: Coronary artery disease Mortality in the U.S. Ma. JACI 2014; 133(4):

13 Summary Anaphylaxis is an acute, potentially life-threatening, systemic allergic reaction Common triggers include foods, stinging insects, allergen immunotherapy Epinephrine is the treatment of choice for anaphylaxis Thank You 13