Chronic Pain Management Flashcards
(20 cards)
what is pain
an unpleasant sensory and emotional experience, associated with actual tissue damage or described in terms of such damage
what is the pathway of pain
latertal spinothalamic tracts
a delta/ c fibres
lamina I and V
V- thalamus, somatosensory cortex= sensory
I- parabrachial, amygdala hypothalamus = attention/ affective (creates emotional aspect of pain)
how does peripheral tissue injury change the nervous system
peripheral sensitisation
-a reduction in the threshold of peripheral afferent nociceptors
central sensitisation
-increased excitability of spinal neurones, rewiring in the spinal cord, changes in the brain
what are the features of chronic regional pain syndrome
allodynia- pain in response to non painful stimulus
hyperalgesia
swelling
blue, white, red skin colour changes
hair and nail changes (both can become hyperkeratotic)
osteopenia
what are the main types of pain
nociceptive- from injury via normal nervous syste,
neuropathic- generated within the nervous system
others ic flammatory pain
also mixed pain
what does neuropathic pain feel like
burning, shooting, tingling, sensitivity - allodynia and hyperalgesia
what is seen on examination in neuropathic pain
sensory changes
what are the common causes of neuropathic pain
shingles (post herpetic neuralgia) surgery trauma diabetic neuropathy amputation
what is the drug management for neuropathic pain
tricyclic antidepressants (amitriptyline) anticonvulsants (gabapentin) opioids (morphine) NMDA antagonists (ketamine) sodium channel blockers (lignocaine) capsaicin GABA agonists (baclofen)
what drugs are used in childrens neuropathic pain
topical:
- levomenthol
- capsaicin
- lidocaine
tricyclics (amitriptyline)
gabapentin/ pregabalin
what are the causes of chronic pain in cancer survivors
post surgical pain chemotherapy (induces peripheral neuropathies) chronic graft vs host disease radiation induced pain syndrome hormonal therapy and arthralgias
what are the non drug methods of pain relief
TENS acupuncture nerve blocks intrathecal drug delivery systems spinal cord stimulation physiotherapy occupational therapy psychology
what drugs are commonly used for chronic pain
Tricyclics Gabapentin or Pregabalin Carbamazepine Duloxetine Lidocaine (patch) Opioids Ketamine (memantine) Cannabinoids
what is progression from acute pain to chronic linked with
child anxiety and parental catastrophising (fear of pain), depression, and sleep quality
what is erthromalagia
burning in hand and feet due to dysfunctional v gated sodium channels
what are SCN9A diseases
problems in voltage gates sodium channels
mutation- paroxysmal extreme pain disorder
dysfunctional- congenital inability to express pain
what type of amputation in more conducive to phantom pain
delayed amputations
what happens in brain after amputations
remapping of sensory homunculus
what are opioids good and bad for
effective for pain
esp nociceptive pain
less good for neuropathic pain
some pain not opioid sensitive
not good for fibromyalgia
dependence
what are the side effects of opioids
hormonal (adrenal, libido)
immunomodulation
hyperalgesia
