Management of Chronic Pain Flashcards
What are the two ways peripheral tissue injury changes the nervous system?
Peripheral sensitisation = reduction in threshold of peripheral afferent nociceptors
Central sensitisation = increased excitability of spinal neurons, rewiring in spinal cord, changes in brain
What are the symptoms of chronic regional pain syndrome?
Allodynia, hyperalgesia, swelling, hair and nail changes, osteopenia
What is neuropathic pain?
Pain generated within the nervous system = burning, shooting, tingling
What are some features of the examination in a patient with neuropathic pain?
Allodynia = pain from stimulus not normally painful Hyperalgesia = more pain than expected
What are some causes of neuropathic pain?
Post herpetic neuralgia, surgery, trauma, diabetic neuropathy, amputation
What is the management of neuropathic pain?
Most often tricyclics (amitriptyline) and anticonvulsants (gabapentin)
Others = opioids, NMDA antagonists, sodium channel blockers, capaicin, GABA agonists
What are some agents used to treat chronic pain in children?
Topical levomenthol or capsaicin
Lidocaine patch
Amitriptyline or gabapentin/pregabalin
What are some causes of chronic pain in cancer survivors?
Surgery, chemo/radiotherapy, chronic graft vs host disease, hormonal therapy and arthralgias
What alternative therapies are offered to treat chronic pain in cancer survivors?
Physiotherapy, occupational therapy or psychology
TENS, acupuncture, nerve blocks or spinal cord stimulation
What drugs are used to treat chronic pain in cancer survivors?
Tricyclics, gabapentin/pregablin, carbamazepine, duloxetine, lidocaine patch, opioids, ketamine, cannaboids
What gene has been implicated in pain?
SCN9A = causes patient to feel no pain if absent and increased pain if abnormal
How many alpha and beta subunit types are present in human voltage gated sodium channels?
9 types
What are some disorders of voltage gated sodium channels that are implicated in chronic pain?
SCN9A paroxysmal extreme pain disorder and SCN9A congenital inability to express pain = Nav 1.7 mutations
Erthromyalgia = burning in hands/feet, leaky Nav 1.7
What are some examples of physical methods of torture?
Beating, burning, mutilation, hooding, rape, sensory deprivation, solitary confinement
What are some forms of torture?
Witnessing or being forced to participate in torture of family and compatriots
Deprivation of food, water and basic needs
Physical
