Anaphylaxis Flashcards
What is the action of epinephrine?
Stimulates the SNS by vasoconstricting the peripheral vascular system to drive blood back to the brain/organs. It also vasodilates the airway
Signs of respiratory failure in pt with anaphylaxis’s?
Wheezing, crackles, laryngeal edema
Normal dose of epinephrine?
0.5 mg or 500 mcg
What is cell mediated vs humoral immunity?
CM- adaptive immunity provided by lymphocyte stem cells (T cells)
HI- aka antibody mediated immunity, types of adaptive immunity that uses antigen antibody interactions to neutralize/destroy foreign proteins
What is innate vs adaptive immune system?
I- body’s first line of general defence (you’re born with it), consists of natural protective feature of human body to prevent organisms from entering (like the skin)
A- body’s 2nd response when exposed to microbes, responds by using antigens to generate an immune response
What are immunoglobulins?
They are antibodies they recognize and bind to specific antigens to help with their destruction
Type 1 hypersensitivity reaction?
Onset <1 hr, has increased IgE production and arises from inflammation caused by overactive immunity. Person will experience allergic response to a first time exposure which causes symptoms like itchy, red eyes, hives. Can also lead to anaphylaxis.
What is anaphylaxis and S+S?
Rapidly develop S+S that involve at least 2 body systems (integ, resp, PVS, CVS, GI). S+S: itchy, rash that gets worse, progressive swelling of face/mouth/tongue, sneezing, coughing, wheezing, SOB, hoarseness, difficulty swallowing, rapid/weak pulse, hypotension, N/V, loose stools, abdominal pain
What is type 2 cytotoxic hypersensitivity response?
Autoantibodies are formed/directed against self cells. Onset is 2-5 minutes. Example is hemolytic transfusion (nausea, chills, headache, back pain, fever, tachycardia, hypotension). Also a penicillin allergy
What is type 3 immune complex mediated hyper. response?
Antigens cause immune complexes to form in blood which lodge in the kidneys, joints, and lungs. This causes decreased blood flow and increase in vascular permeability. Examples- chronic organ transplant rejection, autoimmune disorder, serum sickness, arthus reaction
What is type 4 delayed response?
T lymphocytes activate macrophages to create a protective response (cell mediated) and destroys the antigen. S+S: edema, irritation, ischemia, tissue damage. Examples- contact dermatitis (poison ivy, drugs, metal), graft/organ transplant rejection
Which types of hypersensitivity disorder are humoral vs T cell mediated?
Type 1, 2, 3 are humoral and type 4 is cell mediated
How to manage mild-moderate duration allergic reactions?
Often no treatment (will resolve on its own) but can give antihistamines for itchy
Primary treatment for anaphylaxis?
Epinephrine
How to manage anaphylaxis step by step?
- Stop/remove causative agent
- Determine dose of epi and give it IM vastus lateralis
- Position pt on their back/in a comfy position if they’re SOB or reps distress
- Elevate lower extremities and monitor VS and LOC continuously
- Call code blue
- Repeat epi q5 min for continued/worsening signs (max 3 doses)
- Document time of onset of anaphylaxis and time epi was adminstered
- Intitiate CPR if unresponsive with no pulse
What medication is given after epi?
Benadryl to help with antihistamine effect (itchiness and edema). IV is the best route
What is angioedema?
Severe type 1 reaction that involves blood vessels/all layers of the skin in the affected area. Causes by ingested drug/chemical. S+S: swelling of lips, face, tongue, neck, difficulty speaking/swallowing because of the swelling
