Intro To Pain

Question 1

At what period does acute pain become termed chronic pain?

Answer 1

12 weeks

Question 2

What period of time is termed ‘sub-acute’ Pain?

Answer 2

<6 weeks

Question 3

Which are the main afferent pain fibres that transmit pain from the nociceptors?

Where do they travel to and synapse?

Answer 3

A delta and C

They synapse with secondary afferent neurones in the dorsal horn root ganglion

Question 4

What is the main pain pathway (tract)?

Is it anterior or posterior sub-division?

Answer 4

The lateral spino-thalamic pathway

Question 5

What does the thalamus do?

Answer 5

Relays sensory information

Question 6

What division of the brain is the thalamus in?

Answer 6

Diencephalon

Question 7

Where are opioid receptors located with respect to the structure of nerves?

Answer 7

Nerve terminals

Question 8

What are the advantages of multi-modal analgesia?

Answer 8

1) opioid sparing = if benzo is used, opioid can be reduced by 20-30%
2) analgesics work synergistically
3) better side effect profiles

Question 9

Name the weakest 2 opioid.

Answer 9

Tramadol

Codeine - weakest

Question 10

Name the strongest opioids, from morphine upwards.

Answer 10

Morphine
Oxycodone
Methadone
Fentanyl 
Remifentanyl

Question 11

What is the other name of paracetamol?

Answer 11

Acetaminophen

Question 12

What are the 2 non-opioid drugs for pain relief?

Answer 12

Paracetamol

NSAIDS

Question 13

What are all other drugs that aid pain relief but do not treat it called?

Answer 13

Adjuvants

Question 14

What is central sensitization?

Answer 14

Constant pain and nociception input remodels the way it is processed

Question 15

What is allodynia?

Answer 15

Pain sensitization to things that are not normally painful

Question 16

What is hyperalgesia?

Answer 16

Painful stimuli becomes increasingly more painful

Question 17

What is the main excitatory neurotransmitter in the CNS?

Answer 17

Glutamate

Question 18

What is the main inhibitory neurotransmitter in the CNS?

Answer 18

GABA

Question 19

What is the NMDA receptor?

Answer 19

A glutamate receptor

Question 20

Name an NMDA receptor antagonist.

Answer 20

Ketamine

Question 21

What is pharmacokinetics?

Answer 21

What the body does to the drug

Question 22

What is pharmacodynamics?

Answer 22

What the drugs do to the body

Question 23

Name the 4 main parts of pharmacokinetics.

Answer 23

Absorption
Distribution
Metabolism
Excretion

Question 24

What class of drug is amitriptyline?

Answer 24

Tricyclics antidepressant

Question 25

What class of drug is pregabalin/gabapentin?

Answer 25

Anticonvulsant

Question 26

What are anticonvulsants and tricyclics antidepressants used for other than their main uses?

Answer 26

Neuropathic pain

Question 27

What receptors are found in nociceptors?

What triggers them?

Answer 27

TRPV1

They are triggered by temp/pH/capsasin

Question 28

Where do the primary and secdary afferent neurones in the spinothalamic tract decussate?

Answer 28

At level of entry (or 1-2 spinal nerve segments above)

Question 29

What are the 2 receptors for glutamate called?

Answer 29

AMPA

NMDA

Question 30

What are substance P receptors called?

Answer 30

NK receptors

Question 31

Where are opioid receptors located in relation to the synapse and what do they do when activated?

Answer 31

They are pre-synaptic

They hyperpolarize cells by opening K+ channel and also block Calcium influx, which in turn prevents neurotransmitter release

Question 32

Which neurotransmitter is both excitatory and inhibitory?

Answer 32

Dopamine

Question 33

What is the main inhibitory neurotransmitter in descending pain pathways?

Answer 33

5-HT