Bb Allergic Reactions

Front 1

How does epinephrine work during anaphylaxis?

Back 1

1. beta effects inhibit the release of histamine from mast cells,
2. alpha effects counter hypotension,
3. beta 2 bronchodilates and inhibits mediator release by increasing cyclic AMP in mast cells and basophils

Front 2

What are anaphylactic reactions mediated by?

Back 2

antibodies (IgE); require prior exposure to the antigen;
-antigen antibody complex attach to wall of mast cell and stimulate histamine release

Front 3

what is the main difference between anaphylactoid and anaphylactic reactions?

Back 3

anaphylactoid-antibodies are not required to release histamine
- histamine release is independent of an antibody-antigen reaction
- Ags attach to mast cells and release histamine without binding first to an antibody

Front 4

what are the effects of histamine?

Back 4

-similar to hypoxia, namely pulmonary vasoconstriction and systemic vasodilation which lead to:
1. urticaria
2. erythema
3. bronchospasm
4. laryngeal edema
5. hypotension
6. cardiovascular collapse

Front 5

what is the treatment of anaphylactic reactions?

Back 5

1. stabilization patient-CPR/ACLS,
2. administer 1-3 L crystalloid,
3. give epi in 10 ug IV increments until hypotension is corrected - relaxes bronchial smooth muscle, inh release of histamine); if severe epi 0.005-0.010 mg/kg or about 0.5-1.0 mg in a 70 kg pt
4. antihistamines - Benadryl 0.5 mg/kg

Front 6

what is the mechanism of antihistamines for treatment of anaphylaxis?

Back 6

compete with histamine at receptor sites and attenuate the effects

Front 7

What are the effects of stimulation of H1 and H2 receptors?

Back 7

H1-bronchoconstriction
H2-acid production by parietal cells and cardiovascular effects

Front 8

What are clues to a diagnosis of allergic reaction?

Back 8

hypotension, bronchospasm, laryngeal edema

Front 9

If patients have a history of allergic reactions and they are undergoing a procedure known to cause anaphylaxis what should you do to decrease the risk of a reaction?

Back 9

H1(benadryl) and H2 blockers (ranitidine or famotidine) can be given in advance and this can decrease the severity of the reaction

Front 10

What are the treatment of the specific symptoms of allergic reactions?

Back 10

1. hypotension-ABC,
2. bronchospasm-epi,
3.laryngeal edema-fluids,
4. erythema-cutaneous symptoms-benedryl

Front 11

What patient's are considered high risk for latex allergy?

Back 11

1. health care workers,
2. spina bifida,
3. patients with congenital urologic problems,
4. patients with hx of atopy (esp to rubber gloves and banana)
5. rubber industry workers

Front 12

What is thought to be the cause of latex allergy?

Back 12

allergens involved are probably water soluble proteins of the rubber, not chemical additives

Front 13

What contact can lead to latex allergy?

Back 13

1. direct skin contact,
2. involvement of mucous membranes,
3. inhalation,
4. intravascular absorption

Front 14

what is the treatment of a latex reaction in the OR?

Back 14

1. D/C anesthetics,
2. 100% O2,
3. remove all latex,
4. aggressive IVFs,
5. epi,
6. antihistamines,
7. bronchodilators,
8. steroids, and
9. bicarb as indicated,

Front 15

What is the role of steroids or H1/2 blockers in prevention of a latex reaction?

Back 15

there is none

Front 16

In a patient with a PCN allergy when is it appropriate to give a cephalosporin?

Back 16

if the reaction was mild (i.e. rash)

Front 17

why do you give vancomycin slow?

Back 17

minimize histamine release

Front 18

What are the features of red man syndrome with vanco and what is the cause?

Back 18

1. flushing of face and neck,
2. pruritis,
3. hypotension;
-rapid infusion of vanco with subsequent histamine release

Front 19

What are reactions encountered with vanco?

Back 19

1. local phlebitis(10%),
2. red man syndrome,
3. acute chest pain,
4. ototoxicity (occurs if levels remain>60mg/L for several days),
5. nephrotoxicity (rare),
6. neutropenia (rare)

Front 20

What is recommended time in which Vanco should be administered?

Back 20

over 60 min

Front 21

You recommend brachial plexus block for a 17 y/o boy who requires ORIF of an open wrist fracture. Pulses at the wrist are absent. He is a full stomach. Mother informs you that she and his older sister are both "allergic to xylocaine" received for dental procedures. Each suffered pallor, tachycardia, anxiety, ad unconsciousness after mandibular blocks. The most appropriate action is to?

Back 21

Recommend general anesthesia with rapid induction and intubation.

Front 22

Antibiotics implicated in antibody mediated anaphylactic reactions

Back 22

1. cephalosporins
2. PCNs
3. Vancomycin

Front 23

Antibiotics and other drugs implicated in non-antibody mediated, anaphylactoid reactions

Back 23

1. Vanco
2. Basic compounds ie Morphine
3. Hyperosmotic agents ie Mannitol