20 Allergic Reaction

Multimedia Directory Slide 31 Allergic Reaction—Anaphylaxis Video Slide 32 Information About Allergic Rhinitis Video These videos appear later in the presentation; you may want to preview them prior to class to ensure they load and play properly. Click on the links above in slideshow view to go directly to the slides.

Topics Allergic Reactions Self-Administered Epinephrine Planning Your Time: Plan 70 minutes for this chapter. Allergic Reactions (40 minutes) Self-Administered Epinephrine (30 minutes) Note: The total teaching time recommended is only a guideline. Core Concepts: How to identify a patient experiencing an allergic reaction Differences between a mild allergic reaction and anaphylaxis How to treat a patient experiencing an allergic reaction Who should be assisted with an epinephrine auto-injector

Allergic Reactions Teaching Time: 40 minutes Teaching Tips: Relate the pathophysiology of anaphylaxis to previous lessons on shock and respiratory problems. Discuss how the signs and symptoms may be similar. Multimedia graphics may be helpful in demonstrating patient assessment of an allergic reaction. Use examples of real-life allergic reaction and anaphylaxis to add realism to pathophysiology. Spend time discussing how to differentiate anaphylaxis. Epinephrine is not a benign drug, and EMTs should take care to give it only in the correct circumstances. Teach providers to be constantly alert for anaphylaxis. Rapid changes occur.

Allergic Reactions Immune system naturally responds to foreign substances in body. Allergic reaction Exaggerated response to foreign substance Allergen Substance causing exaggerated effect Covers Objective: 20.3 Point to Emphasize: An allergic reaction is an exaggerated immune response to a foreign invader in the body. continued on next slide

Allergic Reactions Inside First exposure Immune system forms antibodies. Antibodies identify and attempt to attack particular foreign substance. Antibodies combine only with allergen they were formed in response to. Covers Objective: 20.3 continued on next slide

Allergic Reactions Inside Second (and subsequent) exposures Antibodies exist. Antibody combines with allergen, leading to release of histamine and other chemicals into bloodstream. Chemicals cause harmful effects. Covers Objective: 20.3 continued on next slide

Allergic Reactions Outside Effects of histamine and other chemicals Inflammation (swelling) Bronchoconstriction Vasodilation Covers Objective: 20.4 Knowledge Application: Have students work in small groups. Assign each group a negative effect of an allergic reaction (for example: bronchoconstriction). Have each group describe how assessment would identify that effect (for example: bronchoconstriction = wheezes). continued on next slide

Allergic Reactions Anaphylaxis Severe, life-threatening allergic reaction Can cause: Rapid dilation of blood vessels (hypotension) Airway swelling (airway obstruction) Bronchoconstriction (respiratory failure) Covers Objective: 20.4 Point to Emphasize: Anaphylaxis is a severe and systemic form of an allergic reaction and should be considered a life-threatening emergency. Discussion Topic: Define allergy. How is an allergic reaction different from an anaphylactic reaction? continued on next slide

Allergic Reactions Common allergens Insects Foods Plants Medications Others Dust, makeup, soap, etc. Covers Objective: 20.5 Point to Emphasize: Food, insect bites and stings, plants, and certain medications can cause allergic reactions. Discussion Topic: Discuss the potential causes of an allergic reaction. Describe at least three common allergies. Knowledge Application: Assign common causes of allergy. Ask students to research and report on prevalence, severity, and morbidity and mortality. Critical Thinking: How might an ingested allergen cause a different reaction from that of an injected allergen? Why might these reactions present differently?

Substances that may cause allergic reactions. Common Allergens Covers Objective: 20.5 Point to Emphasize: Food, insect bites and stings, plants, and certain medications can cause allergic reactions. Discussion Topic: Discuss the potential causes of an allergic reaction. Describe at least three common allergies. Knowledge Application: Assign common causes of allergy. Ask students to research and report on prevalence, severity, and morbidity and mortality. Critical Thinking: How might an ingested allergen cause a different reaction from that of an injected allergen? Why might these reactions present differently? Substances that may cause allergic reactions.

Allergic Reactions Latex allergy Common concern in EMS Many patients have latex sensitivity Providers can develop latex allergy from prolonged exposure Covers Objective: 20.5 continued on next slide

Allergic Reactions No way to predict exact course of an allergic reaction. Severe reaction often takes place immediately, but can be delayed 30 minutes or more. Mild allergic reaction can rapidly progress to anaphylaxis. Covers Objective: 20.6 continued on next slide

Allergic Reactions Signs and symptoms Skin Itching Hives Flushing (red skin) Swelling of the face Warm, tingling feeling in face, mouth, chest, feet, or hands Covers Objective: 20.6 Talking Points: Swelling (edema) is most common in the face (especially the eyes and lips), neck, hands, feet, or tongue.

Signs and Symptoms: Skin Covers Objective: 20.6 Talking Points: Swelling (edema) is most common in the face (especially the eyes and lips), neck, hands, feet, or tongue. Signs of an allergic reaction may include facial swelling. © Edward T. Dickinson, MD

Signs and Symptoms: Hives Covers Objective: 20.6 Talking Points: Hives, also known as urticaria, can be localized, especially around the area of a bite or sting, or generalized, presenting over wide areas of the body. Signs of an allergic reaction may include hives. © Edward T. Dickinson, MD

Allergic Reactions Signs and symptoms Respiratory Tightness in throat or chest Cough Rapid, labored, and/or noisy breathing Hoarseness, muffled voice, loss of voice Stridor Wheezing Covers Objective: 20.6 continued on next slide

Allergic Reactions Signs and symptoms Cardiac Increased heart rate Decreased blood pressure Covers Objective: 20.6 continued on next slide

Allergic Reactions Signs and symptoms Generalized findings Itchy, watery eyes Headache Runny nose Sense of impending doom Covers Objective: 20.6 continued on next slide

Allergic Reactions Signs and symptoms of shock Altered mental status Flushed, dry skin or pale, cool, clammy skin Nausea or vomiting Changes in vital signs Increased pulse, respirations Decreased blood pressure Covers Objective: 20.6 Point to Emphasize: Anaphylaxis can be identified by the signs of an allergic reaction plus airway, breathing, or circulatory challenges. Discussion Topic: Describe the common signs and symptoms of an allergic reaction and of anaphylaxis. What signs are specific to anaphylaxis?

Distinguishing Anaphylaxis from Mild Allergic Reaction Any of previous signs and symptoms can be associated with an allergic reaction. Anaphylaxis Patient has either respiratory distress or signs and symptoms of shock. Covers Objective: 20.6 Point to Emphasize: Patient assessment will determine if the patient is having an anaphylactic reaction or just an allergic reaction. Beware, however, for allergy can rapidly progress to anaphylaxis.

Patient Assessment Primary assessment Identify and treat life-threatening problems. Airway Breathing Circulation Covers Objective: 20.6 continued on next slide

Patient Assessment Secondary assessment History of allergies Exposure What was the patient exposed to? How (what method/route) was the patient exposed? Signs and symptoms Progression Interventions Covers Objective: 20.6 Class Activity: Describe scenarios involving various patients having allergic reactions and anaphylactic reactions. Have a class discussion about whether the signs and symptoms described in each case would be classified as an allergic reaction or an anaphylactic reaction. Knowledge Application: Use a programmed patient and/or multimedia graphics. Demonstrate various types of allergic reactions and ask groups of students to use patient assessment to identify anaphylaxis. continued on next slide

Patient Assessment Assess baseline vital signs. Obtain remainder of past medical history. Covers Objective: 20.6

Patient Care Manage patient's airway and breathing. Apply high-concentration oxygen if patient is in distress or appears to be having an anaphylactic reaction. Mild allergic reactions do not require oxygen. If not breathing, adequately provide artificial ventilations. Covers Objective: 20.6 continued on next slide

Patient Care Consider assisting patient with epinephrine auto-injector. If patient is not wheezing or showing signs of respiratory distress or shock: Continue with assessment. Consult medical direction regarding use of auto-injector. Covers Objective: 20.6 continued on next slide

Patient Care When use of auto-injector may be appropriate If patient has come in contact with substance that caused allergic reaction in the past If patient also has respiratory distress or exhibits signs and symptoms of shock Covers Objective: 20.7 Discussion Topic: Discuss the indications for epinephrine. continued on next slide

Patient Care After using auto-injector Record administration of auto-injector Transport patient Reassess after 2 minutes Covers Objective: 20.6 Knowledge Application: Describe various patients with allergic reactions. Ask students whether they would administer epinephrine. Critique the decision and discuss.

After Administering Auto-Injector Covers Objective: 20.6 Knowledge Application: Describe various patients with allergic reactions. Ask students whether they would administer epinephrine. Critique the decision and discuss. 11. Perform a reassessment, paying special attention to the patient's ABCs and vital signs en route to the hospital.

Think About It Should you administer an auto-injector for a simple allergic reaction? What assessment findings would indicate the need for epinephrine? Covers Objectives: 20.6 and 20.7 Talking Points: You should probably not administer epinephrine for a simple allergic reaction. Epinephrine is a potent drug with potential complications and should not be given without serious consideration. In this case medical control may be able to offer better insight. The findings that would indicate administration in a patient with an allergic reaction include respiratory distress and shock.

Allergic Reaction—Anaphylaxis Video Covers Objective: 20.3 Video Clip Allergic Reaction—Anaphylaxis What causes anaphylaxis? What happens to the patient's blood pressure during an anaphylactic reaction? Explain why a severe allergic reaction can result in respiratory failure. Click on the screenshot to view a video on the topic of anaphylactic shock. Back to Directory

Information About Allergic Rhinitis Video Covers Objective: 20.3 Video Clip Information About Allergic Rhinitis What is allergic rhinitis? What happens when someone with a sensitized immune system inhales an allergen? Discuss the role of histamine in an allergic reaction. What are some treatments for allergic rhinitis? Click on the screenshot to view a video on the subject of allergic rhinitis. Back to Directory

Self-Administered Epinephrine Teaching Time: 30 minutes Teaching Tips: Relate epinephrine to previous discussions on the sympathetic nervous system. Discuss how they relate. Have epinephrine auto-injectors and/or auto-injector training devices on hand for demonstration purposes. Always follow sharps safety procedures when handling actual injectors. Take time to discuss anaphylaxis and the true indications of epinephrine. Compare these indications with potential side effects of the medication. Discuss the absolute need for reassessment.

Self-Administered Epinephrine Commonly prescribed to patients with a history of allergy Auto-injectors are common for people to carry or have at home. Hormone produced by body Constricts blood vessels Dilates bronchioles Covers Objective: 20.8 Point to Emphasize: Epinephrine is a natural hormone produced by the body. It is given in cases of anaphylaxis to constrict blood vessels and dilate the bronchioles. Discussion Topic: Describe the indications for the use of epinephrine. continued on next slide

Self-Administered Epinephrine If authorized by medical direction, you can administer or help patient administer dose of epinephrine from auto-injector that has been prescribed for patient by a physician. Covers Objective: 20.8 continued on next slide

Self-Administered Epinephrine Side effects Increased heart rate Increased cardiac workload Covers Objective: 20.8 Point to Emphasize: Epinephrine is indicated in anaphylactic reactions but not in localized allergic reactions. Discussion Topic: Describe the side effects of the use of epinephrine. Class Activity: Present a variety of allergic reaction and anaphylaxis scenarios to the class. Ask students whether they would administer epinephrine. Discuss the decision-making process. continued on next slide

Self-Administered Epinephrine Administering auto-injector Spring-loaded needle and syringe with a single dose of epinephrine Upon administration, medication automatically releases and injects. Covers Objective: 20.9 Point to Emphasize: An auto-injector is a spring-loaded needle and syringe with a single dose of epinephrine that will automatically release and inject the medication. People with severe allergies commonly carry these devices to deploy in the event of an anaphylactic reaction. Knowledge Application: Review various types of epinephrine auto-injectors. Review the steps in administering each type.

Epinephrine auto-injectors: EpiPen® and EpiPen Jr.® Covers Objective: 20.9 Point to Emphasize: An auto-injector is a spring-loaded needle and syringe with a single dose of epinephrine that will automatically release and inject the medication. People with severe allergies commonly carry these devices to deploy in the event of an anaphylactic reaction. Knowledge Application: Review various types of epinephrine auto-injectors. Review the steps in administering each type. Epinephrine auto-injectors: EpiPen® and EpiPen Jr.®

Self-Administered Epinephrine Administering auto-injector Obtain patient's prescribed auto-injector and ensure: Prescription is written for patient. Medication is not discolored. Medication has not expired. Obtain order from medical direction. Remove safety cap. Covers Objective: 20.9 Point to Emphasize: Always consider the "five rights" of medication administration before administering an epinephrine auto-injector. Knowledge Application: Use programmed patients and practice assisting with an epinephrine auto-injector. Pay particular attention to explaining the steps to the patient. continued on next slide

Self-Administered Epinephrine Administering auto-injector Press tip of auto-injector firmly against patient's thigh (outside of thigh midway between the knee and waist). Hold injector in place until medication is injected. Covers Objective: 20.9 Discussion Topics: Describe the steps involved in correctly administering an epinephrine auto-injector. Describe the circumstances that might indicate the need for additional epinephrine administration. continued on next slide

Self-Administered Epinephrine Administering auto-injector Record administration and time. Carefully dispose of single-dose injector in biohazard container Save two-dose injector Covers Objective: 20.9 Discussion Topics: Describe the steps involved in correctly administering an epinephrine auto-injector. Describe the circumstances that might indicate the need for additional epinephrine administration.

Additional Doses of Epinephrine Reassessment may show patient condition deteriorating. Additional doses of epinephrine may be necessary. Requires on-line medical control Requires bringing patient's additional auto-injectors in ambulance Covers Objective: 20.10 Point to Emphasize: In a severe anaphylactic patient, additional doses of epinephrine may be necessary. Knowledge Application: Use programmed patients to present reassessment scenarios. Have students work through the decision-making process of secondary epinephrine administration. continued on next slide

Additional Doses of Epinephrine If no auto-injector available: Request ALS intercept. Treat for shock. Covers Objective: 20.7 Class Activity: Take a voluntary class poll. Find out what types of allergies are present in the class. How severe have prior reactions been? Ask willing students to discuss.

Pediatric Note Two sizes of auto-injectors Adult dose 0.3 mg Children's dose (for child less than 66 pounds) 0.15 mg Covers Objective: 20.9 Skill Demonstration: Using a manikin and an auto-injector training device, demonstrate the proper procedure for administering medication via an auto-injector device.

Chapter Review

Chapter Review Allergic reactions are common. Anaphylaxis, a true life-threatening allergic reaction, is rare. continued on next slide

Chapter Review The most common symptom in these cases is itching. Patients with anaphylaxis will also display life-threatening difficulty breathing and/or signs and symptoms of shock. Patients with anaphylaxis will be extremely anxious. Their bodies are in trouble and are letting them know it. continued on next slide

Chapter Review The signs and symptoms of anaphylaxis result from physiological changes: vasodilation, bronchoconstriction, leaky capillaries, and thick mucus. continued on next slide

Chapter Review By quickly recognizing the condition, consulting medical direction, and administering the appropriate treatment, you can literally make the difference between life and death for these patients.

Remember In an allergic reaction, the body's immune system overreacts to an allergen and causes potentially harmful side effects. Anaphylaxis is a severe, systemic form of allergic reaction; it is a life-threatening emergency. continued on next slide

Remember EMTs must use assessment to differentiate a localized allergic reaction from a systemic anaphylactic reaction. Epinephrine is useful in anaphylaxis because it constricts dilated blood vessels and opens bronchial passages. continued on next slide

Remember Epinephrine has potentially dangerous side effects and should be used only in the event of anaphylaxis.

Questions to Consider What are the indications for administration of an epinephrine auto-injector? List some of the more common causes of allergic reactions. Talking Points: Indications include signs of an allergic reaction plus respiratory distress and/or shock. Allergic reactions are caused by an exaggerated immune response. Common allergens include medications, insects, and foods. continued on next slide

Questions to Consider List signs or symptoms of an anaphylactic reaction associated with each of the following: Skin Respiratory system Cardiovascular system Talking Points: Skin signs include flushing, tingling sensation, and hives. Respiratory signs include difficulty breathing, wheezing, and difficulty speaking. Cardiovascular signs include increased heart rate, hypotension, and pale skin.

Critical Thinking A 24-year-old male ate a meal that he believes contained shellfish. He is allergic to shrimp. He is sweating and nervous. He appears to be breathing adequately. You do not note any wheezing or stridor. continued on next slide

Critical Thinking His face is slightly red. His pulse is 88 strong and regular, respirations 24, blood pressure 108/74, and skin warm and moist. Should you administer epinephrine? Talking Points: Probably not yet and definitely not until you contact medical control. Although this patient is at high risk due to his known allergy, he does not yet have the signs of anaphylaxis. He is breathing normally and no signs of shock are present. You should reassess frequently and consult medical control.