Download Chapter 21

MASTER TEACHING NOTES
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Detailed Lesson Plan
Chapter 21
Anaphylactic Reactions
50–65 minutes
Case Study Discussion
Teaching Tips
Discussion Questions
Class Activities
Media Links
Knowledge Application
Critical Thinking Discussion
Chapter 21 objectives can be found in an accompanying folder.
These objectives, which form the basis of each chapter, were developed from the new Education Standards and Instructional Guidelines.
Minutes
Content Outline
I.
5
15
Master Teaching Notes
Introduction
Case Study Discussion
A. During this lesson, students will learn about assessment and emergency
care for patients suffering from allergic reaction.
B. Case Study
1. Present The Dispatch and Upon Arrival information from the chapter.
2. Discuss with students how they would proceed.
II. Anaphylactic Reaction—Pathophysiology of Anaphylactic Reaction
A. The immune system is a defense mechanism to fight off invasion by foreign
substances.
B. Antigens are foreign substances that are recognized by the cells of the
immune system and eventually destroyed.
C. When an antigen enters the body, it sets off an immune response, and the
immune system produces antibodies, proteins that search for the antigen,
combine with it, and help to destroy it.
D. If an allergen, a type of antigen, enters the body, it can cause an abnormal
response by the immune system known as an allergic reaction.
E. An allergic reaction is a misdirected and excessive response by the immune
system to an allergen. The response can be local or systemic.
F. A life-threatening allergic reaction is known as an anaphylactic reaction (also
anaphylaxis or anaphylactic shock).
1. Swelling in the upper and lower airways can cause breathing difficulties
and hypoxia.
2. Dilated blood vessels and capillaries can decrease blood pressure and
cause shock.
G. Sensitization
1. An allergic reaction usually does not occur the first time the body is
exposed to and produces antibodies against a particular antigen.
2. Hypersensitivity can develop upon first exposure, meaning if the person
PREHOSPITAL EMERGENCY CARE, 9TH EDITION
DETAILED LESSON PLAN 21

What is your general impression of the
patient?
 What is the first action you should take?
Weblink
Go to www.bradybooks.com
and click on the mykit link for Prehospital
Emergency Care, 9th edition to access a
web resource on the immune system and
allergic reactions.
Discussion Question
What is the relationship between an allergic
reaction and anaphylaxis?
Video Clip
Go to www.bradybooks.com
and click on the mykit link for Prehospital
Emergency Care, 9th edition to access a
video on allergic rhinitis.
PAGE 1
Chapter 21 objectives can be found in an accompanying folder.
These objectives, which form the basis of each chapter, were developed from the new Education Standards and Instructional Guidelines.
Minutes
Content Outline
Master Teaching Notes
is again exposed to the antigen, an allergic reaction will occur.
3. The process of developing hypersensitivity on first exposure to an
antigen is known as sensitization and primes the patient for a possible
anaphylactic reaction.
4. During sensitization, antibodies attach to mast cells and basophils.
When the antigen is reintroduced into the body, the cell membranes
break down and release chemical mediators (such as histamine) that
cause the signs and symptoms of anaphylaxis.
5. Life-threatening responses from the chemical mediators include
bronchoconstriction, increase in capillary permeability, and vasodilation.
H. Anaphylactoid reaction
1. Sometimes mast cells and basophils can release chemical mediators the
first time the antigen is introduced into the body without the patient ever
being sensitized. This is referred to as an anaphylactoid reaction.
2. Signs, symptoms, and treatment are exactly the same as for
anaphylactic reaction.
3. See Table 21-1 for substances that commonly cause anaphylactoid
reactions.
I. Causes of anaphylactic reaction
1. Some causes of anaphylactic reaction are idiopathic (cannot be
identified).
2. How antigens enter the body
a. Injection
b. Ingestion
c. Inhalation
d. Contact (absorption)
3. Common causes of anaphylactic reaction
a. Venom
b. Foods
c. Pollen
d. Medications (penicillin)
e. Other substances (glue)
f. Exercise
g. Latex
PREHOSPITAL EMERGENCY CARE, 9TH EDITION
DETAILED LESSON PLAN 21
Critical Thinking Discussion
How does the body’s response to an
allergen result in signs and symptoms of
anaphylaxis?
Discussion Question
What are some common causes of
anaphylaxis?
Animation
Go to www.bradybooks.com
and click on the mykit link for Prehospital
Emergency Care, 9th edition to access an
animation on anaphylactic reaction.
PAGE 2
Chapter 21 objectives can be found in an accompanying folder.
These objectives, which form the basis of each chapter, were developed from the new Education Standards and Instructional Guidelines.
Minutes
Content Outline
Master Teaching Notes
III. Anaphylactic Reaction—Assessment-Based Approach to
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Anaphylactic Reaction
A. Scene size-up
1. Be certain your own safety is not in jeopardy (especially if anaphylactic
reaction is the result of a bite or sting).
2. Look for clues at the scene such as medications.
B. Primary assessment
1. Patient may complain of not feeling well or malaise, generalized feeling
of weakness or discomfort.
2. Closely assess the airway for signs of obstruction (stidor or crowing
sounds).
3. Positive pressure ventilation may be necessary to force the air past the
swollen upper airway.
4. If breathing is adequate, place the patient on a nonrebreather mask with
an oxygen flow of 15 lpm.
5. Management of the airway may require endotracheal intubation,
placement of a tube in the trachea to facilitate breathing. In most
jurisdictions, this is performed by ALS.
6. Common signs of allergic reaction
a. Rapid and weak pulse (fluid loss)
b. Warm, flushed skin (vasodilation)
c. Hives (capillary permeability and leaking in the epidermis)
d. Edema (capillary permeability and leaking in the dermis)
7. Patient with an anaphylactic reaction is considered priority; consider
calling ALS.
8. Determine if the patient has an epinephrine auto-injector and locate it
immediately.
C. Secondary assessment
1. If the patient is experiencing a severe reaction, conduct the secondary
assessment en route to the hospital.
2. History
a. Use the OPQRST line of questioning, with emphasis on the onset of
the reaction.
b. The faster the onset of signs and symptoms of an anaphylactic
reaction, the more severe and prolonged the reaction will probably
be.
c. Take the patient’s SAMPLE history.
PREHOSPITAL EMERGENCY CARE, 9TH EDITION
DETAILED LESSON PLAN 21
Class Activity
Provide ample opportunity for students to
practice skills.
PAGE 3
Chapter 21 objectives can be found in an accompanying folder.
These objectives, which form the basis of each chapter, were developed from the new Education Standards and Instructional Guidelines.
Minutes
Content Outline
Master Teaching Notes
3. Signs and symptoms
a. Skin
i. Warm, tingling feeling in face, mouth, chest, feet, and hands
ii. Intense itching
iii. Hives
iv. Flushed or red skin
v. Swelling to the face, lips, neck, hands, feet, and tongue
b. Respiratory system
i. “Lump in the throat”
ii. Tightness in the chest
iii. High-pitched cough
iv. Tachypnea
v. Labored breathing
vi. Noisy breathing
vii. Impaired ability to talk or hoarseness
viii. Excessive amounts of coughed-up mucus
ix. Partially or completely occluded airway
x. Difficulty in breathing
c. Cardiovascular system
i. Tachycardia
ii. Hypotension
iii. Irregular pulse
iv. Absent radial pulse
d. Central nervous system
i. Increased anxiety
ii. Lightheadedness
iii. Unresponsiveness
iv. Disorientation
v. Restlessness
vi. Seizures
vii. Headache
e. Gastrointestinal system
i. Naseau/vomiting
ii. Abdominal cramping
iii. Diarrhea
iv. Difficulty in swallowing
v. Loss of bowel control
f. Genitourinary system
PREHOSPITAL EMERGENCY CARE, 9TH EDITION
DETAILED LESSON PLAN 21
Discussion Question
What are signs and symptoms of
anaphylaxis?
Weblink
Go to www.bradybooks.com
and click on the mykit link for Prehospital
Emergency Care, 9th edition to access a
web resource on urticaria.
PAGE 4
Chapter 21 objectives can be found in an accompanying folder.
These objectives, which form the basis of each chapter, were developed from the new Education Standards and Instructional Guidelines.
Minutes
Content Outline
Master Teaching Notes
i. Urgent need to urinate
ii. Cramping of the uterus
g. Generalized signs and symptoms
i. Itchy, watery eyes
ii. Runny or stuffy nose
iii. Sense of impending doom
iv. Complaints of “not feeling well”
v. General weakness or discomfort
vi. Physical exam
vii. Baseline vital signs
h. Two key categories of signs and symptoms
i. Airway and respiratory compromise—Airway occlusion;
respiratory distress or respiratory failure with possible wheezing
or stridor
ii. Shock (hypoperfusion—Absent or weak pulses; rapid heartbeat;
decreased blood pressure; deteriorating mental status
4. Physical exam
a. Focus the physical exam on the patient’s complains involving the
airway, breathing, and circulation.
b. The EMT’s major concerns are a compromised airway, inadequate
breathing, and shock (hypoperfusion).
c. Check the face for swelling and extremities for bites, stings, or
injection marks.
d. Check pulses and skin temperature, color, and condition for
indications of shock.
5. Baseline vital signs—Pay particular attention to the breathing, pulse, and
blood pressure.
6. Remember that what appears to be a mild allergic reaction can progress
to a severe, life-threatening reaction within minutes. Do not mistake
anaphylaxis for other conditions with similar signs and symptoms.
D. Emergency medical care
1. Distinguish between a mild and a moderate-to-severe reaction.
2. The mild reaction typically does not require aggressive intervention or
administration of medication. Maintain an open airway, provide oxygen,
and transport as soon as possible.
3. Emergency care for a moderate to severe reaction.
a. Maintain a patent airway.
b. Suction any secretions.
PREHOSPITAL EMERGENCY CARE, 9TH EDITION
DETAILED LESSON PLAN 21
PAGE 5
Chapter 21 objectives can be found in an accompanying folder.
These objectives, which form the basis of each chapter, were developed from the new Education Standards and Instructional Guidelines.
Minutes
Content Outline
Master Teaching Notes
c. Maintain oxygen therapy.
d. Be prepared to assist ventilation.
e. Administer epinephrine by a prescribed auto-injector (on-line or offline order).
f. Consider calling for advanced life support.
g. Initiate early transport.
E. Reassessment
1. Patient with a mild reaction should be constantly monitored for
indications that the reaction is worsening and that further intervention
may be needed.
2. Patient with moderate-to-severe reaction who has received an
epinephrine injection should be reassessed to determine if the injection
has been effective (after two minutes).
3. Closely reassess the airway, breathing, and circulation status and looks
for signs of deterioration.
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Discussion Question
What are the treatment priorities for
patients with anaphylaxis?
IV. Anaphylactic Reaction—Summary: Assessment and Care
A. Review assessment findings that may be associated with allergic reaction
and emergency care for allergic reaction.
B. See Figures 21-3 and 21-4.
Knowledge Application
V. Anaphylactic Reaction—Epinephrine Auto-Injector
A. Epinephrine is the drug of choice for the emergency treatment of moderateto-severe allergic reactions.
B. Epinephrine’s alpha1 and alpha2 properties cause vasoconstriction and
tighten the capillaries, reversing the increased capillary permeability
experienced by the anaphylactic patient.
C. The beta2 properties cause bronchodilation, reversing the
bronchoconstriction.
D. The beta1 properties are responsible for side effects from administration.
E. Epinephrine also reduces the effects of antihistamine.
F. Body’s response to epinephrine is rapid; however, it only lasts ten to 20
minutse.
G. Epinephrine comes packaged in a disposable delivery system for selfadministration (EpiPen® and Twinject®)
1. Autojectors with spring-loaded, concealed needle designed to deliver a
precise dose of epinephrine
Teaching Tip
PREHOSPITAL EMERGENCY CARE, 9TH EDITION
DETAILED LESSON PLAN 21
Given a scenario involving exposure to an
allergen, students should be able to
determine treatment priorities for the
patient.
Pass around examples of epinephrine autoinjectors for students to see and handle.
Critical Thinking Discussion
What are the actions of epinephrine that are
beneficial to the patient with anaphylaxis?
Weblink
Go to www.bradybooks.com
and click on the mykit link for Prehospital
Emergency Care, 9th edition to access a
web resource on the epinephrine autoinjector and anaphylaxis.
PAGE 6
Chapter 21 objectives can be found in an accompanying folder.
These objectives, which form the basis of each chapter, were developed from the new Education Standards and Instructional Guidelines.
Minutes
Content Outline
Master Teaching Notes
2. Twinject® is unique because it carries two doses of epinephrine.
3. Both epinephrine auto-injectors carry a 0.3 mg dose for patients 66
pounds or greater and 0.15 mg for infants and children up to 66 pounds.
4. Activated by pressing it against the patient’s thigh (lateral portion,
midway between the hip and knee preferred); second dose of Twinject®
requires additional steps
5. Preferable to move clothing from the injection site but not necessary.
VI.
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Follow-Up
Animation
Go to www.bradybooks.com
and click on the mykit link for Prehospital
Emergency Care, 9th edition to access an
animation on allergic reactions and
epinephrine.
Case Study Follow-Up Discussion
A. Answer student questions.
B. Case Study Follow-Up
1. Review the case study from the beginning of the chapter.
2. Remind students of some of the answers that were given to the
discussion questions.
3. Ask students if they would respond the same way after discussing the
chapter material. Follow up with questions to determine why students
would or would not change their answers.
C. Follow-Up Assignments
1. Review Chapter 21 Summary.
2. Complete Chapter 21 In Review questions.
3. Complete Chapter 21 Critical Thinking.
D. Assessments
1. Handouts
2. Chapter 21 quiz
Why is the immediate application of
oxygen an important aspect of Mrs.
Stein’s treatment?
 What is the significance to Mrs. Steins’
treatment and recovery of the inability to
pinpoint the exact time the symptoms
began?
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Class Activity
Alternatively, assign each question to a
group of students and give them several
minutes to generate answers to present to
the rest of the class for discussion.
Teaching Tips
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Answers to In Review and Critical
Thinking questions are in the appendix
to the Instructor’s Wraparound Edition.
Advise students to review the questions
again as they study the chapter.
 The Instructor’s Resource Package
contains handouts that assess student
learning and reinforce important
information in each chapter. This can be
found under mykit at
www.bradybooks.com.
PREHOSPITAL EMERGENCY CARE, 9TH EDITION
DETAILED LESSON PLAN 21
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