Anaphylactic Response

Question 1

Types of hypersensitivity

Answer 1

Type 1: immediate hypersensitivity

• production of IgE antibody immediate.
• leads to vascular dilation, edema, smooth muscle contraction, inflammation
• associated w/ anaphylaxis, allergies and asthma

Type 2: antibody mediated hypersensitivity

• production of IgG, IgM which destroys cells and recruits leukocytes
• leads to inflammation and functional degeneration of tissues.
• associated w/ autoimmunity and good pasture syndrome

Type 3: immune complex mediated hypersensativity

• antigen-antibody complexes are deposited on tissue. Leads to leukocytes and compliment activation
• leads to inflammation and necrotizing vasculitis
• associated w/ SLE and serum sickness

Type 4: cell-mediated hypersensitivity

• T-lymphocytes relaxes inflammatory cytokines and macrophages
• leads to edema and granuloma formation
• associated w/ dermatitis, MS, TB and type 1 diabetes

Question 2

What cells produce histamine, the primary mediator of anaphylaxis?

Answer 2

Mast cells and basophils

Question 3

Sequence of events in immediate hypersensitivity reactions

Answer 3

Allergen exposure

Activation of TH2 cells and IgE class switch

Production of IgE

Binding of IgE to mast cells

Repeat exposure to antigen

Activation of mast cells and relapse of mediators

Immediate hypersensitivity reaction versus late phase reaction

Question 4

Common triggers for anaphylaxis

Answer 4

Food allergies

Medications

Insect stings/bites

Latex

Opiates

Exercise

Question 5

What is necessary to initiate an anaphylaxis response?

Answer 5

Sensitization to an offending agent

1) 1st exposure = NO REACTION
- IgE memory B cells form and are produced
- IgE binds to mast cells

2) 2nd exposure = instant degranulation of mast cells REACTION

Question 6

Secondary anaphylaxis

Answer 6

Anaphylaxis response occurs later than expected (usually 2-48hrs after)

Question 7

Systems affected during anaphylaxis and the symptoms associated

Answer 7

Skin (most common)

• hives
• itching
• flushing skin
• swelling

Airway (2nd most common)

• tightness of chest
• swelling of the throat
• scratchy throat
• dyspnea
• wheezing

Central nervous system (least common)

• anxiety
• headache
• dizziness
• confusion
• tunnel vision
• syncope

GI tract

• nausea
• abdominal cramping
• vomiting
• diarrhea

Cardiovascular system

• chest pain
• low BP (vasodilation)
• tachycardia
• syncope

Question 8

Histamine effects in anaphylaxis

Answer 8

Affects all 5 organ systems
- is the prime mover of anaphylaxis

Primary action however is rapid dilation of blood vessels and induces hypotension
- if hypotension is <90/60mmHg, worry about it

also can induce dysrhythmias

Question 9

Cysteinyl Leukotriens effects on anaphylaxis

Answer 9

Effects the respiratory and cardiovascular and integumentary systems

Question 10

Platelet activating factors (PAFs) effects on anaphylaxis

Answer 10

Cardiovascular and integumentary systems

Question 11

What are the two primary causes of death in anaphylaxis

Answer 11

Airway obstruction w/ hypoxia
- caused by inflamed airways or dysrhythmias / AV blocks

Hypotension

Question 12

primary Treatment of anaphylaxis

Answer 12

Treat w/ adrenaline/epinephrine and oxygen saturation

- use fluid replacement when needed

Question 13

Secondary additional treatment for anaphylaxis

Answer 13

For reduction of inflammation:
- Antihistamines and cortisone

To open airways better
- albuterol (beta agonist)

make sure to give epi-pens for home use and must be injected into the thigh (5x higher immediate serum concentration in thigh compared to arm)

Question 14

What are quick relief asthmatic specific treatments?

Answer 14

• Short acting beta agonist: albuterol
• Ipratopium
• corticosteroids
• can use Leukotriene modifiers (singulair) for long term management*

Question 15

What are potential life threatening results after treatment of anaphylaxis?

Answer 15

ST elevations

Secondary reactions