NUR 254 CHAP 38

Hypersensitivity

A reflection of excessive or aberrant immune response Sensitization: initiates the buildup of antibodies Types of hypersensitivity reactions: Anaphylactic: type I Cytotoxic: type II Immune complex: type III Delayed-type: type IV

Allergic Reaction

Allergen triggers the B cell to make IgE antibody, which attaches to the mast cell. When that allergen reappears, it binds to the IgE and triggers the mast cell to release its chemicals.

Allergy

An inappropriate, often harmful response of the immune system to normally harmless substances Hypersensitive reaction to an allergen initiated by immunologic mechanisms that is usually mediated by IgE antibodies

Collaborative Problems and Potential Complications

Anaphylaxis Impaired breathing Nonadherence to therapeutic regimen

Immunoglobulins and Allergic Response

Antibodies (IgE, IgD, IgG, IgM, and IgA) react with specific effector cells and molecules and function to protect the body IgE antibodies are involved in allergic disorders. IgE molecules bind to an allergen and trigger mast cells or basophils. These cells then release chemical mediators such as histamine, serotonin, kinins, SRS-A, and neutrophil factor. These chemical substances cause the reactions seen in allergic response.

Other Allergic Disorders

Contact dermatitis Atopic dermatitis Drug reactions (dermatitis medicamentosa) Urticaria and angioneurotic edema Food allergy Serum sickness Latex allergy

Rhinitis—Planning

Goals may include Restoration of normal breathing pattern Increased knowledge about the causes and control of allergic symptoms Improved coping with alterations and modifications Absence of complications

Allergic Rhinitis

Hay fever, seasonal allergic rhinitis A common respiratory allergy presumed to be mediated by a type I hypersensitivity Affects 10% to 25% of the population Symptoms include sneezing and nasal congestion, clear watery discharge, nasal itching, itching of throat ands soft palate, dry cough, hoarseness, headache May affect the quality of life, producing fatigue, loss of sleep, and poor concentration

Rhinitis—Assessment

Health history Include personal and family history Allergy assessment Subjective data include symptoms and how the patient feels before symptoms become obvious Note relationship between symptoms and seasonal changes, emotional problems, or stress Identify nature of antigens, seasonal changes in symptoms, and medication history

Management of Patients With Allergic Disorders

History and manifestations; comprehensive allergy history Diagnostic tests CBC: eosinophil count Total serum IgE Skin tests: note precautions! Screening procedures

Rhinitis—Diagnoses

Ineffective breathing pattern related to allergic reaction Deficient knowledge about allergy and the recommended modifications in lifestyle and self-care practices Ineffective individual coping with chronicity of condition and need for environmental modifications

Rhinitis—Intervention: Teaching

Instruction to minimize allergens Use of medications Desensitization procedures

False An antibody, not an antigen, is a protein substance developed by the body in response to and interacting with a specific antigen, not antibody.

Is the following statement true or false? An antigen is a protein substance developed by the body in response to and interacting with a specific antibody.

Rhinitis—Intervention: Breathing

Modify the environment to reduce allergens Reduce exposure to people with URI Take deep breaths and cough frequently

Medication

Oxygen, if respiratory assistance is needed Epinephrine used for anaphylactic reactions Histamines Corticosteroids

Chemical Mediators

Primary Histamine Eosinophil chemotactic factor of anaphylaxis Platelet-activating factor Prostaglandins Secondary Leukotrienes Bradykinin Serotonin

Prevention and Treatment of Anaphylaxis

Screen and prevent! Treat respiratory problems, oxygen, intubation, and cardiopulmonary resuscitation as needed Epinephrine 1:1,000 subcutaneously Auto injection system: EpiPen May follow with IV epinephrine IV fluids

Cetirizine (Zyrtec) A common second-generation nonsedating antihistamine used to treat allergies is cetirizine (Zyrtec). First-generation antihistamines include chlorpheniramine (Chlor-Trimeton), diphenhydramine (Benadryl), and hydroxyzine (Atarax).

What is a common second-generation nonsedating antihistamine used to treat allergies? Cetirizine (Zyrtec) Chlorpheniramine (Chlor-Trimeton) Diphenhydramine (Benadryl) Hydroxyzine (Atarax)

4 hours A "rebound" anaphylactic reaction can occur 4 to 10 hours after an initial attack even when epinephrine has been given.

When could a "rebound" anaphylactic reaction occur after an initial attack even when epinephrine has been given? 1 hour 2 hours 3 hours 4 hours

Atopy

refers to the allergic reactions characterized by IgE antibody action and a genetic predisposition

Allergen

the substance that causes the allergic response