non-opioids and adjuvants

Question 1

where do non-steroidal anti-inflammatory drugs (NSAIDs) work

Answer 1

on blocking the COX2 sites to stop the production of prostaglandins which decreased activation threshold

Question 2

what do COX1 help to produces/ cause

Answer 2

• homeostasis
• prostaglandins
• prostacyclin
• thromboxane A2

Question 3

what does COX2 help to produce/ cause

Answer 3

inflammatory prostaglandins

Question 4

what does 5-lipoxygenase help to produce/ cause

Answer 4

inflammatory leukotrienes

Question 5

what is involved in the inflammatory pathway after arachidonic acid

Answer 5

• COX1
• COX2
• 5-LOX

Question 6

what are examples of NSAIDS

Answer 6

• aspirin
• ibuprofen
• diclofenac
• naproxen
• piroxicam

Question 7

what adverse affects can NSAIDS cause

Answer 7

• GI disturbance
• Skin reactions
• bronchospasm
• reversible renal insufficiency

Question 8

what are the adverse affects of paracetamol

Answer 8

• liver failure

Question 9

what are examples of anti-depressents

Answer 9

• tricyclic antidepressants eg amitriptyline
• serotonin-norepinephrine reuptake inhibitors eg duloxetine

Question 10

what is the mechanism of action of antidrepessents

Answer 10

1. inhibit 5-HT reuptake
2. enhances descending inhibition of neuropathic pain
3. increase on 5-HT and dopamine reinforce the inhibitory effect of NA in an auxiliary manner

Question 11

what are adverse effects of antidepressents

Answer 11

• mouth dryness
• constipation
• weight gain
• nausea
• dizziness and drowsiness
• erectile dysfunction

Question 12

what are the 2 different types of anticonvulsants

Answer 12

1. voltage gated Na+ channel blockers
2. voltage gated Ca2+ channel modulators

Question 13

how do voltage gated Na2+ channel blocker AEDs work

Answer 13

• blocks the voltage gated Na+ channels
• stops depolarisation
• action potential cannot be created

Question 14

how do voltage gated Ca2+ channel modulator AEDs work

Answer 14

• blocked the alpha1delta subunit of voltage gated Ca2+ channel
• reduces Ca influx
• synaptic vesicles can’t be released
• reduces release of nociceptive neurotransmitters

Question 15

what are the adverse effects of anticonvulsants (AEDs)

Answer 15

• drowsiness
• hyponatremia

Question 16

what is the mechanism of action of ketamine

Answer 16

• blocks NMDA receptors
• reduces wind-up in dorsal horn

Question 17

what are the effects of ketamine

Answer 17

• dissociative anaesthesia
• increased ICP

Question 18

how does ketamine create an effect

Answer 18

• stimulate central sympathetic outflow
• stimulates the heart with increased BP and CO

Question 19

what are the adverse effects of ketamine

Answer 19

• hallucinations
• delirium
• uncontrolled movements

Question 20

what are the contraindications of ketamine

Answer 20

• head trauma
• increased ICP

Question 21

what does magnesium sulfate do

Answer 21

• bronchodilation
• anti-seizure
• membrane stabilising activity
• reduces pain postopritavely

Question 22

how does magnesium sulfate work

Answer 22

• antagonises calcium release
• inhibits catecholamine release
• antagonises NMDA receptors
• anti-inflammatory - reducing IL6 & TNFa why contribute to its analgesia

Question 23

what does lidocaine do

Answer 23

• local anaesthetic
• sodium channel blocking
• regional anaesthesia
• intra and post op analgesia

Question 24

what is nefopam used for

Answer 24

analgesia

Question 25

how does nefopam work

Answer 25

- serotonin, norepinephrine, dopamine reuptake inhibitor - sodium and calcium channels inhibiting glutamatergic transmission

Question 26

how does nitrous oxide work

Answer 26

- inhibits ligand gated ion channels - NMDA receptor antagonism - potentiation of GABA receptor activation

Question 27

how does nitrous oxide produce analgesia

Answer 27

- release of endogenous opioid peptides - target PAG

Question 28

what are the adverse effects of nitrous oxide

Answer 28

- diffusion hypoxia - postop nausea and vomiting - anaemia and neuropathy - recreational use

Question 29

what are the contraindications of nitrous oxide

Answer 29

- decompression sickness - head injuries - impaired consciousness - suspected bowel obstruction - recent middle ear surgery - pneumothroax

Question 30

what is methoxyflurane used for

Answer 30

analgesia acting on brain and spinal cord

Question 31

what does methoxyflurane work on

Answer 31

- GABA receptors - potssium channels - glutamate receptors - glycine receptors - reducing in synapses and condition in neurones

Question 32

how is methoxyflurane administered

Answer 32

inhalation giving 30mins analgesia

Question 33

what are contraindications to methoxyflurance

Answer 33

- malignant hyperthermia - allergies to anaesthetic vapours - impaired consciousness - significant head injury - cardiovascular instability - renal impairment - ventilatory compromise

Question 34

what is the 1st mechanism of action of NSAIDS

Answer 34

- acts as a OGG2 substrate and heme reducing agent - inhibits POX, converting its heme group to an inactive state

Question 35

how does POX become active or inactive

Answer 35

- POX (Fe (IV), active -> POX (Fe(III), inactive) - POX (inactive) -> hydroperoxides -> POX (active) - hydroperoxides shifts to the right making inactive active

Question 36

what is the 2nd mechanism of action of NSAIDs

Answer 36

- conjugated in the brain with arachidonoyl - inhibiting uptake of anandamide - now more present in synaptic celts - acts as an agonist by TRPV1 - inhibits COX2 - causes analgesia and euphoria

Question 37

what is the 3rd mechanism of action of NSAIDs

Answer 37

activates the descending serotonergic pathways