Anaphyalxis

Question 1

Define anaphylaxis

Answer 1

Rapid onset severe life threatening systemic hypersensitivity reaction

Question 2

Most common pathogenesis of anaphylaxis

Answer 2

• IgE dependent food,drugs, insect stings
• mast cells + basophils release histamines, prostaglandins, leukotrienes, tryptases…
• produces symptoms

Question 3

Anaphylaxis symptoms

Answer 3

• angioedema
• stridor
• cough
• wheeze
• dyspnoea
• N+V
• abdo pain
• hypotension + tachycardia (sign)
• syncope
• urticaria

Question 4

What mediator causes most of the anaphylaxis symptoms?

Answer 4

Histamines

Question 5

Diagnosis of anaphylaxis

Answer 5

• acute onset of illness with involvement of skin, mucosal tissues or both
  AND at least one of
• respiratory compromise
• hypotension or symptoms of end organ dysfunction
• severe GI symptoms
  OR
• acute onset of hypotension, bronchi spasm or laryngeal involvement after exposure to a known or highly probable allergen even in absence of skin involvement

Question 6

What posture should a patient be in when in anaphylaxis ?

Answer 6

Lying down or sat up
NOT upright

Question 7

First line treatment of anaphylaxis

Answer 7

High dose adrenaline in anterolateral thigh

Question 8

Outline adrenaline auto injector administration

Answer 8

• form fist around EpiPen
• pull off blue safety release
• place orange to anteriolateral thigh
• push down hard until click is hear or felt
• hold for 3 seconds
• remove
  blue to sky, orange to thigh

Question 9

Acute management of anaphylaxis

Answer 9

• remove trigger
• posture
• IM adrenaline
• IV fluid bolus
• refractory anaphylaxis

Question 10

Long term management of anaphylaxis

Answer 10

Risk assessment
Allergen avoidance
Emergency plans

Question 11

What receptors does high dose adrenaline act on + how does this treat anaphylaxis?

Answer 11

• anaphylaxis causes bronchoconstriction + vasodilation
• the receptors acted on reverse this
• a1: vasoconstiction
• B2: bronchodilation
• B1: increases cardiac output