Anaesthesia Drugs

James HoldingJames Holding

Green for Danger - Rank Films 1946

2009 Anaesthesia2009 Anaesthesia

Intravenous induction Short acting opiate - e.g. fentanyl ‘anaesthetic’ - e.g. propofol Set up of anaesthetic maintenance - e.g.

sevoflurane vapour in oxygen and air Specific muscle paralysis may be needed Definitive analgesia Anti-emetic

Intravenous induction Short acting opiate - e.g. fentanyl ‘anaesthetic’ - e.g. propofol Set up of anaesthetic maintenance - e.g.

sevoflurane vapour in oxygen and air Specific muscle paralysis may be needed Definitive analgesia Anti-emetic

Propofol Propofol

MaintenanceMaintenance

MaintenanceMaintenance

Concepts of partial pressure and MAC

Isoflurane (ISO) – MAC = 1.1 Desflurane (DES) – MAC = 6

The most insoluble – so the fastest to equilibrate – but a respiratory irritant, so unsuitable for gaseous induction.

Sevoflurane (SEVO) – MAC = 2.2 Used for gaseous induction.

Nitrous Oxide – a gas. MAC = 105 Propofol and Remifentanil

Concepts of partial pressure and MAC

Isoflurane (ISO) – MAC = 1.1 Desflurane (DES) – MAC = 6

The most insoluble – so the fastest to equilibrate – but a respiratory irritant, so unsuitable for gaseous induction.

Sevoflurane (SEVO) – MAC = 2.2 Used for gaseous induction.

Nitrous Oxide – a gas. MAC = 105 Propofol and Remifentanil

MAC = minimum alveolar concentration

Muscle ParalysisMuscle Paralysis

Neuromuscular blockersNeuromuscular blockers

Depolarising Suxamethonium

Non-depolarising Atracurium Vecuronium Rocuronium

Depolarising Suxamethonium

Non-depolarising Atracurium Vecuronium Rocuronium

Nicotinic ACh ReceptorNicotinic ACh Receptor

Reversal of ParalysisReversal of Paralysis

Neostigmine Blocks cholinesterase Stimulates nicotinic and

muscarinic Given with an

anticholinergic

Sugammadex

Neostigmine Blocks cholinesterase Stimulates nicotinic and

muscarinic Given with an

anticholinergic

Sugammadex

UppersUppers

Anticholinergics Atropine Glycopyrulate

Symatheto-mimetics agonists

Phenylepherine Metaraminol

Ephidrine A mixed and adreno agonist

Anticholinergics Atropine Glycopyrulate

Symatheto-mimetics agonists

Phenylepherine Metaraminol

Ephidrine A mixed and adreno agonist

DownersDowners

More anaesthetic or opiate

Short acting -blockers (labetalol, esmolol)

GTN

Clonidine - 2 agonist clonidine

More anaesthetic or opiate

Short acting -blockers (labetalol, esmolol)

GTN

Clonidine - 2 agonist clonidine

Opiates

MorphineFentanylAlfentanilRemifentanil

MorphineFentanylAlfentanilRemifentanil

AntiemeticsAntiemetics

AntiemeticsAntiemetics

Cyclizine – an anti-histamine (SE – tachycardia and other anti-cholinergic effects)

Granisetron and ondansatron – 5-HT3 receptor antagonists (SE – constipation)

Prochlorperazine (stematil) – a dopamine and mACh receptor antagonist (SE – extrapyramidal)

Dexamethasone – a glucocorticoid (SE – deranged glucose control)

Cyclizine – an anti-histamine (SE – tachycardia and other anti-cholinergic effects)

Granisetron and ondansatron – 5-HT3 receptor antagonists (SE – constipation)

Prochlorperazine (stematil) – a dopamine and mACh receptor antagonist (SE – extrapyramidal)

Dexamethasone – a glucocorticoid (SE – deranged glucose control)