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
What should be done with factory office doors?
Weather-stripped to minimize industrial odors, fumes, and dust
What should be done about lotions?
Lotions, hairsprays, perfume should be stayed away from
What should be done about copiers?
Some fumes from machine chemicals can provoke allergies
What should be done about felt-tipped markers?
They can emit fumes
What should be done about books?
Books are notorious collectors of mold as well as being natural dust catchers. Keep books closed in the bookcase or closet.
What should be done about mold?
This is a potent allergen and can be minimized by use of dehumidifiers confining humidity in a health 40 percent range: neither too damp, so as to promote mold, nor too dry, so as to dry out the resp. tract
What should be done in the hospital room/bedroom of a patient with allergies?
- No plants or flowers in the room
- Change water in pitchers every shift
- No fuzzy bathrobes
- No fuzzy blankets
- No sheepskin
- No starched sheets or cotton mattres pads
- If eggcrate mattress pad is needed, use the hypoallergenic variety
- No rugs
- Keep closet door shut
- Use pillows with synthetic fill and plastic covers
- No scented soaps or lotions
- No powders
- No aerosols in use in the patient’s vicinity
- No drapes or curtains
- Don’t smoke
- Make sure the room is damp-mopped and dusted daily while the patient is out of the room
- Don’t use cologne or scented cosmetics yourself
How do you desensitize a room for someone with allergies?
- Keep all clothes in closets, never lying about room. Keep closet and all other doors closed
- No orately carved furniture - plain, simple designs catch less dust. avoid books or bookshelves - they are great dust catchers
- Replace favric upholstered furniture items with ones covered by rubberized cavas or plastic.
- Wood or linoleum flooring. No rugs of any kind.
- No toys or stuffed animals in the room. If they must be included, they should be made of wood, plastic, or metal, never fabric
- No pennants, pictures, or other dust catchers on wall
- Allergen-proof encasings are far superior to plastic for pillows, mattresses, and box springs. Vacuum matress and pillow covers frequently
- Washable cotton or synthetic blankets instead of fuzzy surfaced ones
- Use easily laundered cotton bed spread instead of chenille. Wash all items in hot water
- No feather or foam rubber pillows. Use synthetics. Foam rubber grows mold, especially in damp areas
- Install air conditioning window unit, or central air conditioning. keep windows closed especially in summer. no fans
- Install a roll-up washable cotton or synthetic window shades. no blinds
- Use easily washed cooton or fiber glass curtains. no draperies
- In houses with forced air heat, cost of centrally installed electrostatic air filter may be justified. In any case, filter or damp cheesecloth over air inlet helps reduce dust circulation. Change filters at least every two weeks
What is immunotherapy?
A form of treatment to decrease sensitivity to allergens
Who is a candidate for immunotherapy?
Allergic asthma, allergic rhinitis, allergic conjuctivitis, and stinging insect allergy
What is involved with immunotherapy?
Injection of increasing amounts of allergens over months to years
How does immunotherapy work?
Works like a vaccine. The body responds to the injected amounts of a particular allergens by developing tolerance. Allergens more readily combine with IGG and IGE. It reduces allergy symptoms. It does not work for everyone.
What reactions can occur from immunotherapy?
Local: common, redness and swelling at injection site. Treatment: topical steroids, oral antihistamines
Systemic allergy symptoms (sneezing, nasal congestion or hives) or anaphylaxsis. Treatment: epinephrine, prepare to intubate
How does IGE work?
- The first time a person is exposed to an allergen. The B cell reacts
- A large amount of IgE antibody is made by plasma cell
- IgE antibodies attach to mast cells
- The next time the person is exposed to the allergen it binds to the IgE antibodies that are attached to the mast cells. This triggers the release of chemical mediators from the mast cell
