Hypersensitivity - EXAM 5 Flashcards
Latex Allergy Response
Definition: An allergic response to natural latex rubber products
Defining Characteristics: Type I reactions: immediate urticaria, edema of lips, tongue, uvala and/or throat; SOB, tightness in chest, wheezing, and bronchospasm, respiratory arrest; hypotension, syncope, cardiac arrest
TNIs: Identify patients at risk:
- Spina bifida
- more than 3 surgeries
- Children with CRF
- Atopic individuals
- Known or suspected latex allergies
Consider skin testing, complete latex avoidance, find latex-free materials and products, seek medical care as necessary, instruct patient to carry an emergency kid with a supply of non-latex gloves, antihistamines and an epipen
How does knowing which patients are at risk help the RN plan care?
Teaching about avoidance and cross sensitivity can prevent development or minimize exposure
Epinephrine (Adrenalin)
Classifications: antihistamine, sympathomimetic
Mechanism of Action: to stimulate the cardiovascular system and increase BP, cause bronchdilation and decongestion by stimulating alpha and beta receptors
Use: give SC or IV for allergic reactions marked by anaphylaxsis autoinjectors for emergency self-administrationj
Side/Adverse Effects: cardiac dysrhythmias, cerebral hemorrhage and angina
Nursing Implications: routes are SC, IV, IM or VIA airway (nebs or injected through ET tube) for anaphylaxis. Massage injection site to increase rate of absorption
How does the dose of epinephrine for allergies compare to that for cardiac emergencies?
The allergy dose of epinephrine for allergies is smaller. 0.3-0.5mg VS 1 mg for cardiac emergencies
diphenhydramine (Benadryl)
Classification: antihistamine and anticholinergic
Mechanism of Action: inhibits inflammatory effects of histamine
Use: hypersensitivity reactions
Side/Adverse Effects: drowsiness, photosensitivity, dry mouth
Nursing Implications: Routes PO, IV deep IM
How do allergies occur?
Allergens or antigens are substances found in the environment that can cause symptoms in sensitive individuals. These substances gain access to the body through the lungs, skin, mucuous membranes or gastrointestinal tract.
What is a hypersensitivity reaction?
When antigens are recognized as threatening by the immune system, a hypersensitivity reaction can result. B and T cells are responsible for this reaction. What this presents with in a patient depends on whether the chemical mediators remain localized or become systemic
What are the three primary phases of immune response?
- Identification of the allergen/antigen as “nonself”
- The proliferation of immunocompetent cells
- Action against foreign substances
What are local reactions?
Primarily cutaneous. A wheal and flare, urticaria, atopic dermatitis and angioedema are examples.
What are systemic reactions?
Systemic reactions include bronchial constriction, airway obstruction, and vascular collapse
What is anaphylaxis?
The most dangerous type of immune response or hypersensitivity. It occurs within minutes and is often fatal if not treated promptly. Shock rapidly results in a rapid, weak pulse, hypotension, dilated pupils, dyspnea and cyanosis. Bronchial constriction compromises respirations. If the reaction is in a reponse to a medication or allergen that can be avoided, prevention is the best strategy. However, if a person knows that they have an anaphylactic response to an environmental substance such as a bee or insect sting or food they should take additional measures which might include hyposensititation injections or the carrying to epinephrine at all times.
What foods should a person avoid with a latex allergy?
There can be cross reactions to banana, avocado, kiwi, and chestnut
What should be done with drapes?
They are dust catchers. Lightweight, easily washable synthetic curtains are best. Plastic drapes of shower curtain material are virtually “allergy proof.”
What should be done with air conditioners?
Should be vacuum cleaned; filter changed routinely. HEPA filter can eliminate up to 95% of airbourne dust and allergies
What should be done about foam rubber?
Can grow or harbor fungi; use a polyester stuffing instead or spring cushions. Covering should be vinyl plastic or other synthetic material easily wiped clean.
What should be done with windows?
kept closed and sealed against airborne allergens