Week 13 Flashcards
key components of pain processes
- stimulus
- nociceptor
- PNS
- spinal cord
- ascend spinal cord
- brain
what parts of the brain involved in pain
thalamus & cortex
what parts of the ascend spinal cord involved in pain
- spinothalamic (pain)
- spinoreticular (emotional)
when is pain considered chronic
> 3 months
types of pain
- nociceptive
- neuropathic
- nociplastic
location of nociceptive / neuropathic pain
somatic nociceptive pain = localized
visceral nociceptive pain = generalized
neuropathic = follow nerve path / diffuse
pain description of nociceptive / neuropathic pain
somatic nociceptive pain =sharp
visceral nociceptive pain = ache, cramping
neuropathic = burning, tingling, prickling
how does central sensitization of chronic pain development work
persistent pain after injury resolved > signals continue over protracted period of time > amplifies danger > CNS sensitized > more pain felt
central pain
CNS damage > increased pain sensitivity
ischemic pain
hypoxia from decreased blood flow > tissue damage & release of inflammatory mediators which cause pain
phantom pain
pain from limb no longer present
allodynia pain
pain from stimulus which normally does not provoke pain
hyperalgesia pain
increased pain from stimulus that normally provokes pain
referred pain
pain from site other than origin
social management of chronic pain involves
support groups / spirituality / relationships
pharmacological management of chronic pain involves
procedural intervention / physiotherapy / acupuncture / Tui na
education management of chronic pain involves
managing psychiatric disorders such as anxiety / depression
psychological management of chronic pain involves
cognitive behavioral therapy / meditation / mindfulness
systemic pharmaco pain management
analgesics / anti-epileptics / anti-depressants / adjuvants / opoids
regional pharmaco pain management
peripheral nerve block / central neuraxial
simple analgesics effective for __
nociceptive pain
caution when using paracetamol include __
low body weight / liver pathology
paracetamol overdose leads to
fulminant liver failure
antidote to fulminant liver failure
IV acetylcysteine
NSAIDs side effects
GI / renal / haematological / CVS
NSAIDs mechanism
cyclo-oxygenase (COX) inhibitions
non-selective COX
diclofenac / ibuprofen / naproxen
COX-2 selective
celecoxib / etoricoxib
COX-1 inhibition leads to __
peptic ulcers, GI bleeding
COX inhibition leads to __
- Na+ & H2O retention
- hypertension
- hemodynamic acute kidney injury
arachiodonic acid affects __
GI / renal / CVS
when more COX-2 inhibited than COX-1
stroke & myocardial infarction occur
opioids effective for ___
nociceptive & neuropathic pain
opioids are good for __
acute pain / short term use for chronic pain / cancer pain
opioids mechanism involves
μ-receptor agonism
opioid toxicity / overdose leads to __
sedation / respiratory depression / apnea
weak opioids include __
codeine / tramadol
strong opioids include __
morphine / pethidine / fentanyl / oxycodone
mechanism of tramadol
inhibit serotonin and noradrenaline uptake
prominent side effects of tramadol
nausea / vomitting
caution when using tramadol
seizures / serotonin syndrome
caution when using morphine
renal impairment / elderly / obesity / OSA
caution when using pethidine
seizures / renal impairment
anti-epileptics & depressants good for __
neuropathic pain
anti-epileptics AKA
gabapentinoids
mechanism of anti-epileptics
alpha2-delta subunit of calcium channel
side effects of anti-epileptics
somnolence, lower limb swelling
caution when using anti-epileptics
potential abuse
tri-cyclic anti-depressants include
amitriptyline / notriptyline (anything that ends with -tryptyline)
serotonin-norepinephrine reuptake inhibitors include
duloxetine, venlafaxine
side effect of anti-depressants
serotonin syndrome
low dose aspirin will irreversibly inhibit __
platelet COX-1
antidote for opioid toxicity/overdose
naloxone
sensitivity of nociceptors increases by substances released from __
tissue damage
what are the 2 types of afferent fibres carrying painful stimuli
myelinated A & unmyelinated C
what are myelinated A-delta
medium size fibre (smaller than Myelinated A-beta) with fast speed of pain transmission
what are unmyelinated C
small fibre with slow transmission for chronic pain
where do primary afferent nerve synapse at
dorsal horn of spinal cord with secondary afferent neurons
what is the purpose of spinothalamic & spinoreticular tract
spinothalamic = pain localization
spinoreticular = emotional aspect of pain
pain interpretation occurs at
somatosensory cortex
pain matrix includes __
- thalamus
- primary & secondary somatosensory cortex
- prefrontal cortex
where does awareness & alertness occur in
reticular formation in pons & medulla
where does stress response come from
hypothalamus
where does emotional response come from
limbic system
activation of ___ has inhibitory effect on dorsal horn
alpha-beta fiber
what is nociceptive pain
pain generated due to tissue damage & elicits reflex withdrawal
