clinical aspects of pain

Question 1

define pain

Answer 1

unpleasant sensory and emotional experience associated with actual or potential tissue damage

Question 2

can you experience pain when you are unconscious

Answer 2

No

Question 3

how is pain classified

Answer 3

duration- acute/chronic

pathophysiology- nociceptive and neuropathic

Question 4

what is the most common cause of acute pain

Answer 4

trauma and injury.

Question 5

what defines chronic pain (timing)

Answer 5

• Pain extends 3-6 months beyond onset

Question 6

why do we get pain

Answer 6

assists wound repair in- acute pain.

Question 7

when does pain resolve

Answer 7

upon healing in acute

doesn’t in chronic

Question 8

what physiologic system regulates the nocioceptive pain mechanisms

Answer 8

opioidergic system

Question 9

what causes noiceptive pain

Answer 9

tissue damage and painful stimuli at noiceptors.

Question 10

what are the main benefits of acute pain

Answer 10

part of trauma response, protective to avoid further damage, learning experience.

Question 11

what are the main adverse effects of acute pain

Answer 11

humanitarian issues, cardiovascular stress, respiratory compromise, hyper coagulation.

Question 12

what factors effect a persons perception of pain

Answer 12

anxiety
depressed
gender- socliasation and gonadotropins
circadian variation
climatic conditions

Question 13

how is pain assessed

Answer 13

Ideally self reported by patient.
Visual analogue- pain scale
Assess pain at rest and during movement.

Question 14

what pain management (medication) is used for pain

Answer 14

Non-opiods- parecetamol, aspirin, NSAID.s COX-2 inhibitors
Opiods for mild to moderate pain- codeine, dihyroceodeine, tramadol.
Opiods for moderate to severe pain- morphine, fentanyl, hydromorphone, buprenorphine, methadone.

Question 15

What is the mechanism of action of NSAID’s

Answer 15

COX inhibitors (act peripherally), decrease prostaglandin synthesis

Question 16

What is the mechanism of action for opiods

Answer 16

Act at 2 sites in spinal cord
Presynaptically pain signal transmission is reduced
Postsynaptically membrane is hyperpolarised, decreasing the probability of action potential generation

Question 17

what are the main side effects of non-opiods

Answer 17

due to change in amount of prostaglandins
o Cardiovascular side effects
o Renal side effects
o GI side effects.

Question 18

what is the main side effects of paracetamol

Answer 18

liver toxicity.

Question 19

what is the mode of action of paracetamol

Answer 19

inhibit central prostaglandin synthesis

Question 20

what examples of non-opiods

Answer 20

parecetamol, aspirin, NSAID.s COX-2 inhibitors

Question 21

what examples of opiods (mild to moderate pain)

Answer 21

codeine, dihyroceodeine, tramadol.

Question 22

what examples of opiods (moderate to severe)

Answer 22

morphine, fentanyl, hydromorphone, buprenorphine, methadone.

Question 23

what are the side effects of opioid analgesics

Answer 23

nauseas, vomiting, constipation, vertigo, sosmnolence, dry skin and pruritus.

Question 24

where are opiod receptors present

Answer 24

found in bowel, pupillary light reflex, control of respiration, chemoreceptor

Question 25

what is the earliest prediction of respiratory depression which is a side effect of respiratory depression

Answer 25

sedation

Question 26

why must opiod levels be measured accurately in analgesia

Answer 26

different people will have different plasma levels of opiods in their blood.

Question 27

what 2 drugs must never be used in renal failure

Answer 27

morphine or codeine

Question 28

what 2 drugs can be used in renal failure

Answer 28

fentanyl and oxycodone

Question 29

what are the main benefits of a epidural

Answer 29

``` High quality pain relief Improved pulmonary function Reduced chest infection and sepsis Reduced cardiac morbidity. Anticipated block from epidural- can be specifically targeted for a specific space. ```

Question 30

what drug is commonly used in cancer treatment

Answer 30

morphine

Question 31

where do spinal opiods work

Answer 31

Act on the dorsal horn

Question 32

which reaches the brainstem lipophillic or lipophobic morphine

Answer 32

lipophobic

Question 33

define neuropathic pain

Answer 33

pain due to damage in pain stimulating system e.g stroke or Type II diabetes.

Question 34

what are the main characteristics of chronic pain

Answer 34

Intense pain Recurrent pain Associated with severe co-morbidity and poor quality of life.

Question 35

define allyodonia

Answer 35

pain to a non painful stimulus/

Question 36

what are the main features of neuropathic pain

Answer 36

Pain different from normal everyday pain Pain in absence of ongoing tissue damage Pain in area of sensory loss! Paroxysmal or spontaneous pain! Allodynia Hyperalgesia Dysaesthesia

Question 37

define hyperalgesia

Answer 37

increased pain in response to painful stimuli

Question 38

define dysaesthesia

Answer 38

unpleasant abnormal sensations “ants crawling on the skin”

Question 39

what drugs are used to treat neuropathic pain

Answer 39

NSAIDs –poor Antidepressants- inhibits neuronal reuptake of noradrenaline and serotonin. Anticonvulsants- dampens down the neuronal pathways. Opiods Membrane stabilising drugs Topical drugs Other.

Question 40

what symptoms are antidepressants used for

Answer 40

neuropathic, complex regional pain and tension headache.

Question 41

what is the mode of action of antidepressants

Answer 41

inhibition of neuronal reuptake or noradrenaline and serotonin.

Question 42

what are the side effects of antidepressants

Answer 42

constipation, dry mouth, somnolence, heart rate, insomnia.

Question 43

what are the symptoms for which anticonvusants are used

Answer 43

neuropathic pain

Question 44

what is the mode of action of antidepressants

Answer 44

o gabapentin- binds presynaptic voltage dependent calcium channels (excreted renally, not metabolised) o Pregabalin- interacts with special N type calcium channels. o Carbamazepine- blocks Na and Ca channels. (rashes and liver damage)

Question 45

what are the side effects of anticonvulsants

Answer 45

sedation, dizziness, ataxia, peripheral odema, nausea, weight gain

Question 46

what machine is used for spinal cord stimulation

Answer 46

TENS machine