Emergency treatment of anaphylaxis in infants and children

Question 1

What is anaphylaxis?

Answer 1

Severe, acute and potentially life-threatening medical condition caused by systemic release of mediators from mast cell and basophils often in response to an allergen with rapid onset

Question 2

What are CNS symptoms of anaphylaxis?

Answer 2

Fussiness, irritability, drowsiness, lethargy, reduced level of consciousness, somnolence

Question 3

What are skin symptoms of anaphylaxis?

Answer 3

Urticaria, pruritus, angioedema, flushing

Question 4

What % of children with anaphylaxis have cutaneous manifestations?

Answer 4

80-90%

Question 5

What are some airway symptoms of anaphylaxis?

Answer 5

Upper: Stridor, hoarseness, oropharyngeal or laryngeal edema, uvular edema, swollen lips/tongue, sneezing, rhinorrhea, upper airway obstruction
Lower: Coughing, dyspnea, bronchospasm, tachypnea, respiratory arrest

Question 6

What % of children with anaphylaxis have respiratory involvement?

Answer 6

60-70%

Question 7

What are some cardiovascular symptoms of anaphylaxis?

Answer 7

Tachycardia, hypotension, dizziness, syncope, arrhythmias, diaphoresis, pallor, cyanosis, cardiac arrest

Question 8

What % of children with anaphylaxis have cardiovascular involvement?

Answer 8

10-30%

Question 9

What are some gastrointestinal symptoms of anaphylaxis?

Answer 9

Nausea, vomiting, diarrhea, abdominal pain

Question 10

What is the clinical criteria for diagnosis of anaphylaxis?

Answer 10

Any one of the following three criteria:

1. Acute onset of an illness with involvement of the skin, mucosal tissue or both and at least one of the following:
   a. Respiratory compromise
   b. Reduced BP or associated symptoms of end-organ dysfunction
2. Two or more of the following that occur rapidly after exposure to a likely allergen for that patient:
   a. involvement of the skin-mucosal tissue
   b. respiratory compromise
   c. reduced BP or associated symptoms of end-organ dysfunction
   d. persistent GI symptoms
3. Reduced BP after exposure to a known allergen for that patient
   a. Infants and children: low sBP or >30% decrease in sBP

Question 11

What epipen should be prescribed?

Answer 11

1. 10-25kg Epipen JR (0.15mg)
2. > 25kg Epipen (0.3mg)
   <10kg make decision epipen JR vs. syringes

Question 12

What is the first line therapy of anaphylaxis?

Answer 12

epinephrine 1:1000 0.01mg/kg IM lateral thigh every 5-15min if symptoms persist

Question 13

What are the second line pharmacologic therapies?

Answer 13

1. PO/IV H1 antagonist - benadryl 1mg/kg (max 50mg) IV/PO or cetirizine PO
2. H2 antagonist - ranitidine 1mg/kg (max 50mg) IV/PO
3. Steroids - prednisone 1mg/kg (max 75mg) PO or methylprednisolone 1mg/kg (max 125mg) IV
4. Salbutamol for bronchospasm

Question 14

What is the management for hypotension?

Answer 14

IV NS bolus 20mL/kg

If persistent epinephrine 0.1-1ug/kg/min IV infusion

Question 15

What manifestations are H1/H2 blockers effective for?

Answer 15

Cutaneous only

Question 16

What is an option for patients on beta-blockers?

Answer 16

Glucagon 20-30ug/kg IV over 5min, then 5-15ug/min IV infusion

Question 17

When can a biphasic reaction occur?

Answer 17

1-72h after onset

Question 18

What % of patients with anaphylaxis experience a biphasic reaction?

Answer 18

5-20%

Question 19

What is the minimum recommended observation period?

Answer 19

4-6h

Question 20

When should a child be admitted to hospital?

Answer 20

1. Live far from medical care
2. Required repeated doses of epinephrine
3. Initial presentation with hypotension or severe respiratory distress
4. Biphasic reaction
5. Consider in patient with peanut allergy, asthma, or use of beta-blockers

Question 21

What are risk factors that may indicate the need to prescribe self-injectable epinephrine?

Answer 21

1. Reaction to trace allergen exposure
2. Repeat exposures likely
3. Specific food triggers known to be associated with severe/fatal reactions i.e. peanut, tree nut, seafood, or milk
4. Generalized urticaria from insect venom
5. Asthma
6. Use of non-selective beta-blockers
7. Initial reaction details unclear, possible anaphylaxis
8. Those living in a remote area away from medical care/access

Question 22

What medications other than epinephrine can be prescribed at discharge?

Answer 22

1. Cetirizine (oral H1 antihistamine) x 3d
2. Ranitidine (oral H2 antihistamine) x 3d
3. Oral corticosteroids

Question 23

What counselling should parents receive at discharge?

Answer 23

1. Signs and symptoms of anaphylaxis
2. Avoidance of triggers
3. Use of self-injectable epinephrine
4. Importance of f/u with an allergy or immunology specialist