Managment of Chronic Pain

Question 1

Define I.A.S.P

Answer 1

An unpleasant sensory and emotional experience, associated with actual tissue damage, or described in terms of such damage

Question 2

What is peripheral sensitisation

Answer 2

A reduction in the threshold of peripheral afferent nociceptors

Question 3

What is central sensitisation

Answer 3

Increased excitability of spinal neurones Rewiring in the spinal cord Changes in the brain

Question 4

What causes pain after injury?

Answer 4

Peripheral sensitisation Central sensitisation

Question 5

What is seen in chronic regional pain syndrome?

Answer 5

Allodynia Hyperalgesia Swelling Blue, red, white Hair, nail changes Osteopenia

Question 6

What are the different types of pain?

Answer 6

Nociceptive pain Neuropathic pain Inflammatory pain

Question 7

What is nociceptive pain?

Answer 7

Pain from injury relayed through a normal nervous system

Question 8

What is neuropathic pain?

Answer 8

Pain generated within the nervous system?

Question 9

What are common descriptions of neuropathic pain?

Answer 9

Burning, shooting, tingling, sensitivity

Question 10

What is seen on examination of a patient with neuropathic pain?

Answer 10

Sensory changes Allodynia Hyperalgesia

Question 11

Define allodynia

Answer 11

Pain from a stimulus that is not normally painful e.g. cotton wool

Question 12

Define hyperalgesia

Answer 12

More pain than expected from a painful stimulus e.g. pin prick

Question 13

What are the common causes of neuropathic pain?

Answer 13

• Shingles, post herpetic neuralgia
• Surgery
• Trauma
• Diabetic neuropathy
• Amputation

Many of unknown origin

Question 14

What agents can be used in the management of neuropathic pain?

Answer 14

• Tricyclic antidepressants (amitriptyline)
• Anticonvulsants (e.g. gabapentin)
• Opioids (morphine)
• NMDA antagonists (ketamine)
• Sodium channel blockers (lignocaine)
• Capsaicin
• GABA agonists (baclofen)

Question 15

Which drugs/agents are more often used in children?

Answer 15

• topical levomenthol
  
  • activator of transient receptor potential melastatin-8 (TRPM8) channels
• ​Topical capsaicin
  
  • depletion of substance P=-a peptide that amplifies or excited most cellular processes
• ​Lidocaine (patch)
• tricyclics (usually amitriptyline)
  
  • inhibit amine reuptake so enhancing inhibition from the brainstem to the spinal cord
• ​gabapentin or pregabalin
  
  • GABA analogues blocking voltage dependent calcium channels

Question 16

What kind of chronic pain may a cancer survivor have?

Answer 16

Post surgical pain

Chemotherapy induced painful peripheral neuropathies

Chronic graft vs host disease

Radiation induced pain syndromes

Hormonal therapies and arthralgias

Question 17

What can be used for resistant pain?

Answer 17

TENS

Acupuncture

Nerve blocks

Intrathecal drug delivery systems

Spinal cord stimulation

Question 18

SCN9A if absent there is __ ___
SCN9A is abnormal there is ______ ____

Answer 18

SCN9A if absent there is no pain
SCN9A is abnormal there is increased pain

Question 19

What may occur as a result of an injury such as an ankle sprain?

Answer 19

Neurodegeneration

Axonal dropout in peripheral nerves

Fear of pain

Cytokine changes

Question 20

What is the role of voltage gated sodium channels in chronic pain?

Answer 20

Painful and painless sodium channelopathies, alpha and beta subunits, 9 types in humans.

Question 21

What does Nav 1.7 mutation cause?

Answer 21

SCN9A Paroxysmal extreme pain disorder

Question 22

What does an issue with Nav 1.7 cause?

Answer 22

SCN9A Congenital inability to express pain

Question 23

What does leaky Nav 1.7 cause?

Answer 23

Erthromalalgia– burning hands and feet

Question 24

What happens after amputation?

Answer 24

Remapping

Question 25

What are the side effects of opioids?

Answer 25

Hormonal (Adrenal, libido)

Immunomodulation

Hyperalgesia (OIH)