1. Dr Rob Stephens Thanks to Drs James Holding and Maryam Jadidi Dr Rob Stephens Thanks to Drs James Holding and Maryam Jadidi

2. Contents Introduction – the classical triad Introduction – general principles Hypnotic Agents Neuromuscular Paralysis Reversal of Neuromuscular Paralysis Analgesia Cardiovascular Drugs – up and down Fluids and Gasses are drugs too!

3. Introduction ‘Anaesthesia’ classically Hypnotic agent- unconsciousness Gas or IV Analgesia Neuromuscular Paralysis Induction, Maintenance, Emergence, Recovery ‘Anaesthesia’ classically Hypnotic agent- unconsciousness Gas or IV Analgesia Neuromuscular Paralysis Induction, Maintenance, Emergence, Recovery

4. Introduction - Principles Pharmacokinetics What the body does to the drug Absorption, distribution, metabolism, elimination Pharmacodynamics What the drug does to the body – ie it’s effects CVS, RS, GI, NS, Other, Side effects Pharmacokinetics What the body does to the drug Absorption, distribution, metabolism, elimination Pharmacodynamics What the drug does to the body – ie it’s effects CVS, RS, GI, NS, Other, Side effects

5. 2013 Anaesthesia Intravenous induction Short acting opiate - e.g. fentanyl Hypnotic ‘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 Others Intravenous induction Short acting opiate - e.g. fentanyl Hypnotic ‘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 Others

6. Hypnosis: Propofol

7. Maintenance Concepts of partial pressure and MAC Sevoflurane (SEVO) – MAC = 2.2 Used for gaseous induction. 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. Nitrous Oxide – a gas. MAC = 105 Oxygen /Air Propofol and Remifentanil Concepts of partial pressure and MAC Sevoflurane (SEVO) – MAC = 2.2 Used for gaseous induction. 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. Nitrous Oxide – a gas. MAC = 105 Oxygen /Air Propofol and Remifentanil

8. Muscle Paralysis

9. Neuromuscular blockers Depolarising Suxamethonium Non-depolarising Atracurium Vecuronium Rocuronium Depolarising Suxamethonium Non-depolarising Atracurium Vecuronium Rocuronium

10. Nicotinic ACh Receptor

11. Reversal 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

12. Analgesia Systemic Simple- paracetamol 1g NSAID – Diclofenac etc Opioids eg morphine 2mg bolus Others – Ketamine Regional – spinal / epidural / blocks Local - infiltration Systemic Simple- paracetamol 1g NSAID – Diclofenac etc Opioids eg morphine 2mg bolus Others – Ketamine Regional – spinal / epidural / blocks Local - infiltration

14. Uppers Anticholinergics Atropine Glycopyrulate 200-600μg Symatheto-mimetics  agonists Phenylepherine Metaraminol 0.25-0.5 mg Ephedrine A mixed  and  adreno agonist 3mg Anticholinergics Atropine Glycopyrulate 200-600μg Symatheto-mimetics  agonists Phenylepherine Metaraminol 0.25-0.5 mg Ephedrine A mixed  and  adreno agonist 3mg

15. Downers More anaesthetic or opiate / analgesia Short acting  -blockers (labetalol, esmolol) GTN Clonidine -  2 agonist clonidine More anaesthetic or opiate / analgesia Short acting  -blockers (labetalol, esmolol) GTN Clonidine -  2 agonist clonidine

16. Antiemetics

17. Cyclizine anti-histamine S/E – tachycardia and other anti-cholinergic effects Ondansatron5-HT 3 receptor antagonists S/E – constipation + long QT Prochlorperazine (‘Stematil’) – DA and mACh receptor antagonist S/E – extrapyramidal Dexamethasone glucocorticoid S/E – deranged glucose control Cyclizine anti-histamine S/E – tachycardia and other anti-cholinergic effects Ondansatron5-HT 3 receptor antagonists S/E – constipation + long QT Prochlorperazine (‘Stematil’) – DA and mACh receptor antagonist S/E – extrapyramidal Dexamethasone glucocorticoid S/E – deranged glucose control

18. Fluids and Gasses are drugs too! Oxygen is a ‘drug’ Intravenous fluids Colloids Crystalloids Blood and products Oxygen is a ‘drug’ Intravenous fluids Colloids Crystalloids Blood and products

19. General Advice Can always give more – can’t take away Caution in Unwell Elderly Hypovolaemic Lots of ways to anaesthetise- don’t worry Can always give more – can’t take away Caution in Unwell Elderly Hypovolaemic Lots of ways to anaesthetise- don’t worry

20. Summary Classical Triad Anaesthesia Temporal sequence Usual sequence Classical Triad Anaesthesia Temporal sequence Usual sequence