neuropathic pain Flashcards
neuropathic pain
pain caused by a lesion or disease of the somatosensory (SS) nervous system
peripheral neuropathic pain
initiated or caused by a primary lesion or disease in the peripheral SS system
central neuropathic pain
pain initiated or caused by a primary lesion or disease in the central SS system
peripheral neuropathic pain examples
- metabolic diabetic
- toxic - alcohol, chemotherapy
- post infectious - HIV, CMV
- post traumatic - post operative, neuroma/nerve entrapment, phantom limb pain
central neuropathic pain examples
spinal cord injury
post stroke pain
Multiple sclerosis
common types of neuropathic pain
post hepatic neuralgia painful diabetic neuropathy low back nerve root pathology spinal cord injury Multiple sclerosis stroke
4 types of pain
noxious
inflammatory
neuropathic
nociplastic
nociceptive pain
noxious stimuli such ass heat, cold, intense mechanical force, chemical irritants
adaptive, high threshold pain
early warning system
inflammatory pain
peripheral inflammation positive symptoms
tenderness promotes repair
adaptive, low threshold pain
pathological pain
neuropathic pain
- neural lesion, positive and negative symptoms
- maladaptive, disease state of nerve symptoms
neuropathic pain
- neural lesion, positive and negative symptoms
- maladaptive, disease state of nerve symptoms
dysfunctional pain
- no lesion, no inflammation
- pain hypersensitivity, spontaneous pain
peripheral sensitisation
a damage nerve regrows and expresses different receptors
receptive field increases
stimuli that doesn’t normally cause pain start to be interpreted as pain - hyperalgesia
hyperalgesia
pain experiences is exaggerated
allodynia
non noxious stimuli causing extreme pain
due to peripheral and central sensitisation
taking a pain history
type, dustribution and location
character of pain
anatomical drawing
nerve territory
duration of complaints
average intensity of pain in the last week
extend of interference with daily activities
further history - exposure to toxins, pain meds, psychological disturbances
positive sensory signs and symptoms of neuropathic pain
dysesthesias
parasthesias
spontaneous pain
stimulus evoked pain
negative sensory signs and symptoms
loss/impairment of sensory quality
numbness and reduced sensation
neuropathic pain diagnosis
diangnostic questionaire
treatment of neuropathic pain
identify the cause
pharmacological
non-pharmacological
interventional
pharmacological treatment for neuropathic pain
- simple analgesics
- NSAIDs
- tramadol/tapentadol
- strong opoids
- adjuvant analgesics
- antidepressants
- anticonvulsants
- local anaesthetics
- NMDA antagonists
- others
concepts for treatment in neuropathic pain
- dampen down peripheral sensitisation in the damaged axon (Na+ channel blockade)
- dampen down central senstization (NMDA antagonists and calcum channel blockers)
- enhancing descending inhibitory pathways (trycyclics/SNRIs and tramadol)
first line treatment for neuropathic pain
- gapabentin
- gabapentin extended release or enacarbil
- pregabalin
- serotonin-noradrenaline reuptake inhibitors
- duloxetine or venlafaxine
- tricyclic antidepressants
second line treatment for nueropathic pain
caopsaicin 8% pathces
lidocaine patches
tramadol
thirrd line treatment for neuropathic pain
botulinum toxin A (subcutaneously - specialist use)
strong opiods
interventions for neuropathic pain
epidural injections for herpes zoster
steroid injections for radiculopathy
SCS for FBSS
SCS for CRPS type 1
non pharmacological aspects of neuropathic pain
physiotherapy massage acupuncture hydrotherapy rehabilitation
