Anaesthetics

Question 1

What are the effects of propofol?

Answer 1

Sedative

Used for induction and maintenance of anaesthesia

Question 2

What is the mechanism of rocuronium?

Answer 2

Acetylcholine receptor antagonist

Acts at the NMJ to prevent depolarisation

Question 3

What is the mechanism of suxamethonium/succinylcholine?

Answer 3

Produces constant depolarisation of the motor endplate at the myoneural junction

Inhibits neuromuscular transmission

Depolarising type neuromuscular blocking agent

Very short half life

Question 4

How can the action of rocuronium be reversed?

Answer 4

Sugammadex

Binds rocuronium (also binds vecuronium)

Question 5

What is the mechanism of metaraminol?

Answer 5

Vasoconstrictor → increases BP

• Sympathomimetic - also has a positive inotropic effect*
• Aramine*

Question 6

What is the mechanism of ketamine?

Answer 6

NMDA receptor antagonist

Causes a “dissociative anesthesia” - analgesia, intact spontaneous breathing (preserved pharyngeal and laryngeal reflexes)

Also acts on muscarinic receptors, descending monoaminergic pain pathways, voltage-sensitive calcium channels and opioid receptors in the brain and spinal cord