Anaphylaxis

Question 1

ASCIA definition of anaphylaxis

Answer 1

Any acute onset illness with typical skin features (urticarial rash or erythema/flushing, and/or angioedema), PLUS involvement of respiratory and/or cardiovascular and/or persistent severe gastrointestinal symptoms.
OR
Any acute onset of hypotension or bronchospasm or upper airway obstruction where anaphylaxis is considered possible, even if typical skin features are not present.

Question 2

Grade 1 Anaphylaxis:

Answer 2

Generalised mucocutaneous signs: Erythema, Urticaria+/- Angioedema

Question 3

Grade 2 Anaphylaxis:

Answer 3

Moderately severe - Multi-organ manifestations including:
• Mucocutaneous signs
• Hypotension, Tachycardia
• Evidence of Bronchospasm, cough, difficult ventilation

Question 4

Grade 3 Anaphylaxis:

Answer 4

Severe-Life Threatening and requiring immediate and specific treatment:
• Cardiovascular collapse
• Bradycardia or Tachycardia, Arrhythmias
• Bronchospasm
• Cutaneous signs may be absent, or present only after correction of hypotension

Question 5

Grade 4 Anaphylaxis:

Answer 5

Cardiopulmonary Arrest

Question 6

Differential diagnosis for cutaneous signs of anaphylaxis:

Answer 6

Direct Histamine Release
Venous Obstruction
Head Down Position
C1-esterase deficiency (Angioedema only)
Mastocytosis
Cold induced anaphylaxis

Question 7

Differential diagnosis for airway/ breathing signs of anaphylaxis:

Answer 7

Direct Histamine Release
Acid aspiration
Exacerbation of asthma
Intubation; Oesophageal intubation
Foreign Body
Difficult airway
Visceral traction
Mastocytosis
Auto PEEP (disconnect from ventilator)
Tension pneumothorax (decompress)

Question 8

Differential diagnosis for hypotension (if considering anaphylaxis):

Answer 8

Direct Histamine Release
Visceral Traction
Vasodilation by drugs
Central Neural Blockade
Drug Overdose
Vasovagal
Hypovolemia
Mastocytosis
Cold induced anaphylaxis

Question 9

Differential diagnosis for cardiopulmonary arrest (if considering anaphylaxis):

Answer 9

Myocardial Ischaemia/Infarction
Electrolyte Abnormality
Sepsis
Blood Loss
Tension Pneumothorax
Cardiac Tamponade
Pulmonary Embolism
Mastocytosis

Question 10

Dose of adrenaline in grade 2 anaphylaxis:

Answer 10

5-20 mcg adult

1-5mcg/kg children

Question 11

Dose of adrenaline in grade 3 anaphylaxis:

Answer 11

100-200 mcg

5-10 mcg/kg children