Adrenaline

Question 1

When is adrenaline commonly indicated for use?

Answer 1

• Cardiac arrest
• Anaphylaxis
• Anaesthesia - control local bleeding

Question 2

How does adrenaline work?

Answer 2

Potent agonist of the α1, α2, β1 and β2 adrenoceptors, causing:

• Vasoconstriction of vessels supplying skin, mucosa and abdominal viscera (mainly α1-mediated)
• Increased in heart rate, force of contraction and myocardial excitability (β1)
• Vasodilatation of vessels supplying the heart and muscles (β2)

Question 3

Why is adrenaline used in anaphylaxis?

Answer 3

Additional effects of adrenaline, mediated by β2 receptors, are bronchodilatation and suppression of inflammatory mediator release from mast cells. Together with its vascular effects, these underpin its use in anaphylaxis, where widespread release of inflammatory mediators from mast cells produces generalised vasodilatation, profound hypotension and often bronchoconstriction

Question 4

What are adverse effects of adrenaline use?

Answer 4

• Adrenaline induced hypertension
• Anxiety
• Tremor
• Headache
• Palpitations
• Angina
• MI
• Arrythmias

Question 5

What drugs can adrenaline interact with?

Answer 5

B-blockers - adrenaline may induce widespread vasoconstriction, because its α1-mediated vasoconstricting effect is not opposed by β2-mediated vasodilatation

Question 6

What dose of adrenaline is given in cardiac arrest?

Answer 6

1mg of 1 in 10000 solution IV after third shock, and repeat every 3-5 minutes

Question 7

What solution of adrenaline would you give in cardiac arrest?

Answer 7

1 in 10000 (1mg/10ml)

Question 8

What dose of adrenaline would you give ina adult experiencing anaphylaxis?

Answer 8

500 micrograms IM - repeated after 5 minute intervals according to clinical picture

Question 9

What weight of adrenaline is in a 1 in 10000 solution?

Answer 9

1mg in 10mL

Question 10

What weight of adrenaline is in 1:1000 solution?

Answer 10

1mg in 1mL