acute med Flashcards
what is the mechanism of aspirin as pain relief
irreversible COX inhibitor = reduce prostaglandins
blocks thromboxane
when should aspirin be avoided
warfarin
breastfeeding
what is the mechanism of NSAIDs as pain relief
reversible COX inhibitor = reduce prostaglandins
reduce inflammation
when should nsaids be avoided
asthma
gastric irriation/ulcer
SSRIs
what is the mechanism of paracetamol as pain relief
thought to block COX = prostaglandin inhibitor
antipyretic
no anti-inflammatory action
what is the mechanism of action of weak opioids
bind to opioid receptors in CNS + GI system
what is the mechanism of action of tramadol
bind to opioid receptors in CNS + GI system
AND
block re-uptake of noradrenaline + serotonin in CNS
how do local anaesthetics work
reversible block to conduction along nerve fibres
by blocking voltage gated Na+ channels
describe what bupivacaine is used for and why
lumbar epidural blocks (with continuous analgesia)
spinal blocks
= slow onset of action
why is levobupivacaine sometimes used
same action as bupivacaine but
fewer side effects
describe the use of lidocaine hydrochloride and why + how does it work and how do you reverse it
effective absorption from mucous membranes
duration is roughly 90 mins (with adrenaline)
prilocaine is an alternative
blockage of Na channels
reversal = lipid emulsion
what is ropivacaine hydrochloride
similar to bupivacaine but less cardiotoxic and less potent
what is tetracaine
topical local anaesthetic
4% gel
used for cannulation/venepuncture
rapidly absorbed
NEVER apply to inflamed/vascular surfaces
what is a systematic effect of local anaesthetics and what is given to counteract this effect
dilation of blood vessels
vasoconstrictors given = adrenaline/epinephrine
= slow flow and prolong anaesthetic
give 2 examples of regional anaesthesia
peripheral nerve block
central neuraxial anaesthesia (spinal block)
