Anaphylaxis

Question 1

Anaphylaxis

Answer 1

severe, life-threatening, type-1 hypersensitivity (IgE mediated) immune reaction.

Question 2

Main causes of anaphylaxis

Answer 2

• food (nuts, shellfish, eggs…)
• insect venom
• medications (penicillin…)
• latex
• idiopathic

Question 3

Clinical features of anaphylaxis

Answer 3

sudden + rapid progression of symptoms
Airway:
- swelling of throat, tongue, lips
- stridor and hoarse voice

Breathing:
- respiratory wheeze
- dyspnoea

Circulation:
- hypotension
- tachycardia

also skin and mucosal changes:
- generalised pruritis
- erythema and/or urticarial rash

Question 4

Management of anaphylaxis

Answer 4

Administer IM adrenaline ASAP

< 6 years = 150mcg
6 -12 years = 300mcg
> 12 years = 500mcg

repeat every 5 mins if needed.

Question 5

Location to administer IM adrenaline

Answer 5

anterolateral middle thigh

Question 6

Refractory anaphylaxis

Answer 6

• respiratory or cardiac problems persist following 2 doses of adrenaline
• give fluids for shock at this point

Question 7

Risk-stratified discharge in anaphylaxis

Answer 7

• observation for 2, 6, or 12hrs following resolution of symptoms depending on severity of reaction
• important because 20% cases become biphasic (returns after resolution)