Anaesthesia Revision Dr Rob Stephens Rob Stephens UCL/UCLH Consultant in Anaesthesia UCLH Hon Senior Lecturer UCL Thanks to Dr Roger Cordery

www.ucl.ac.uk/anaesthesia/people/stephens Google UCL Stephens Google UCL Anaesthesia Student

Contents Anaesthesia Basics Analgesia Fluid Basics Airway /kit Basics

Anaesthesia Basics Check out podcast Conduct of Anaesthesia At www.ucl.ac.uk/anaesthesia/StudentsandTrainees/students

Anaesthesia Triad of Anaesthesia Hypnosis Analgesia +/-Neuromuscular paralysis 

Anaesthesia Triad of Anaesthesia Hypnosis Analgesia +/-Neuromuscular paralysis 

Anaesthesia- Hypnosis Hypnosis= reducing consciouness Either I/v or volatile I/V Thiopentone Propofol CVS RS NS Depressants I/V Ketamine CVS stimulant Dissociative anaesthesia’ RS spared Volatiles- gasses- Sevoflurane, Isoflurane Breathe in, then out CVS depressants, RS vary

Anaesthesia Triad of Anaesthesia Hypnosis Analgesia +/-Neuromuscular paralysis 

Anaesthesia Analgesia Psychology, local, regional, systemic Systemic – ‘ladder’ plus adjvants (extras) Simple –Paracetamol NSAID – oral, I/v s/e GI/platelets/ asthma/renal Opioids = any drug acting on opioid receptors s/e N+Vomit / constipation / RS /NS Weak vs potent I/m , PCA (cautious i/v) Oral ,transdermal Gabapentin, Amitriptyline, Nitrous oxide etc

Anaesthesia Triad of Anaesthesia Hypnosis Analgesia +/-Neuromuscular paralysis 

Anaesthesia Neuromuscular To allow intubation and easy ventilation No movement for surgery NMJ Nicotinic Cholinergic antagonists Non-competitive/depolarising = Sux Competitive/non- depolarising = the others Sux = 2 acetylcholine molecules Others – Atracurium, Rocuronium, Vec.. Reversal- inhibit the enzyme that breaks down Ach (Cholinesterase) with Neostigmine

Anaesthesia: 3 classical phases Preoperative – v important Induction- going to sleep Dangerous Mostly Analgesia, Iv hypnosis, paralysis O2, Air, ABCD Maintenance –during surgery Emergence – once surgery has ended ?postop?

Analgesia Psychology, local, regional, systemic Systemic = ladder + adjuvants Postop pain – depends on expected needs ?Intraop block/epidural Everyone gets Paracetamol regularly 1G QDS ?add NSAID regularly eg Ibuprofen 200-400 TDS ?add DiHydroCoedine regular ?need stronger – oral PRN Oral Morphine ? need stronger - PCA

Analgesia- PCA Patient Controlled Analgesia Morphine IV 1mg/ml §§ 1mg bolus No background 5 min lockout Nursing Obs

Fluid Therapy Everyone gets confused! Think about why you’re called to see patient Hx, Exam, Ix, Management How can you monitor fluid status? Colloids / Crystalloids / Blood products Colloids vs Crystalloids – no evidence

Fluid Therapy Colloids / Crystalloids / Blood products Colloids vs Crystalloids – no evidence Crystalloid – Saline / Glucose / Hartmann’s Saline – Na Cl, add K+, acidosis Glucose = water, no electrolytes, hyponatraemia Hartmann’s- K+, Ca+ less Cl, has lactate, no acidosis Colloids smaller volumes / artificial- allergy gelatin or plant starches in saline/Hartmann’s-like

Fluid Therapy Concept of a ‘Fluid Challenge’ What’s your endpoint / target / want to change ? 200-250ml fluid over 15 mins Doesn’t really matter what Hartmann’s or ‘balanced’ colloid Review patient- has it changed? Get help after 2-3 challenges May need more monitoring / drugs Get help if unwell!

ABG Arterial blood gas Like venous – apart from 0xygen. pH pCO2 sBEx (sHCO3) Oxygen- what’s the Fi02 Other stuff UCLH happen to have bought Eg Na, K, lactate, CO, Hb, MetHb New way of thinking- ‘Stewart’ (gold medal)

Airway Airways obstruct Under Anaesthesia If consciousness reduced Likely if GCS <8

Airway 0 Give Oxygen 1 Airway Manouvers Head tilt / chin lift / jaw thrust 2 Airway Adjuncts Guedel 3 Airway kit eg Laryngeal Mask Airway 4 Definitive Airway Intubate- Cuffed Oral EndoTracheal Tube / Tracheostomy 5 Surgical Airway – Cricothyroid /Tracheostomy

Summary Anaesthesia- triad Hypnosis – IV Gas Analgesia – local, regional systemic Preoperative / 3 phases / Postoperative Fluids Equipment Welcome in theatre anytime