Anaesthetic Drugs Flashcards
what are the three components of general anaesthesia
hypnosis
analgesia
paralysis
what two methods can be used for induction of a GA
IV: propofol
Gas: sevoflurane / desflurane
what can propofol cause
hypotension due to vasodilation
what agent can be used in initiation of GA in patients who are hypotensive pre-op? e.g. from major trauma
ketamine
what channels does ketamine block
NMDA receptors (glutamate receptors)
what analgesics are commonly used in GA?
IV morphine
IV fentanyl
what drugs are used for paralysis in GA?
depolarising agents : e.g. suxamethonium
non-depolarising agents: rocuronium / atracurium
what type of drug is suxamethonium? how does it work?
depolarising muscle relaxant
- inhibits acetylcholine action at neuromuscular junction
side effects of suxamethonium
hyperkalaemia
malignant hyperthermia
suxamethonium apnoea
what is suxamethonium apnoea
rare abnormality in production of plasma cholinesterase’s
- increased duration of action suxamethonium
- respiratory arrest
what is malignant hyperthermia
caused by excessive release of calcium from sarcoplasmic reticulum of skeletal muscles
- rigidity + hyperpyrexia
- autosomal dominant
- Tx: dantrolene (prevents calcium release)
benefits of total intravenous anaesthesia (TIVA) over gas for maintenance of GA
TIVA = Less post op N +V, quicker waking up, more eco-friendly
what is lidocaine
short acting amide local anaesthetic
what is bupivacaine
long acting local anaesthetic
what channels do lidocaine / bupivacaine block
sodium channels
