pain management Flashcards
describe acute pain
recent onset
limited duration
describe chronic pain
lasts 3+ months
often lasts after normal healing with no identifiable cause
what are the two mechanisms of pain
nociceptive
neuropathic
describe nociceptive pain
also known as physiological/inflammatory
has obvious tissue injury
pain is well localised
has protective function
describe neuropathic pain
nervous system damage/abnormality
abnormal processing of pain signals
burning/shooting pain
numbness/tingling
what are some causes of neuropathic pain
increased receptor numbers
abnormal sensitisation of nerves
chemical changes in dorsal horn
loss of inhibitory modulation
what are simple analgesics
paracetamol
NSAIDs - ibuprofen, diclofenac
when can paracetamol be used
for mild pain
for moderate pain in combination with other drugs
what can a paracetamol overdose cause
liver damage
how do NSAIDs work
reduce prostaglandins and inflammatory process to prevent stimulating nociceptors in periphery
what can NSAIDs be used for
nociceptive pain
in combination with paracetamol
what are side effects of NSAIDS/when should they be avoided
stomach ulcers (give with PPIs)
hypertension
bronchospasm in asthmatics
avoid in kidney disease
what are ‘weak’ opioids
codeine
dihydrocodeine
tramadol
what are ‘strong’ opioids
morphine
oxycodone
fentanyl
what are common side effects of opioids
constipation puritis nausea altered mental state respiratory depression
what is codeine good for
mild-moderate nociceptive pain
how does tramadol work
mixed opiate and 5HT/NA reuptake
weak opioid effect + inhibits serotonin and noradrenaline reuptake
what is morphine used for
moderate-severe nociceptive pain and cancer pain
can be given orally, IV, IM, SC, PR, intrathecally
what are anti-convulsants used for
give examples
neuropathic pain
gabapentin
carbamazepine
sodium valproate
side effects of gabapentin
very addictive - cocaine effect
only give if confirmed neuropathic pain
what anti-depressants can be used for pain
amitriptyline
duloxetine
what topical agents can be used for pain
capsaicin
what is amitriptyline
tricyclic anti-depressant
what is amitriptyline used for
neuropathic pain
depression
poor sleep
what are side effects of amitriptyline
glaucoma
urinary retention
what are non-pharmacological options for pain management
acupuncture massage psychological rest, ice, elevation surgery physio explanation + planning counselling input from social worker
what is step 1 of the pain ladder
non-opioids
aspirin
NSAIDs
paracetamol
what is step 2 of the pain ladder
mild opioids
codeine
dihydrocodeine
tramadol
what is step 3 of the pain ladder
strong opioids
morphine
oxycodone
fentanyl
what part of the pain ladder do you use for mild pain
just step 1
what part of the pain ladder do you use for moderate pain
step 1 + step 2
what part of the pain ladder do you use for severe pain
step 1+3
when is the pain ladder less applicable
in neuropathic pain
what is the RAT approach to pain
recognise
assess
treat
what do you assess the pain for
pain score at rest vs with movement
nociceptive or neuropathic
other factors like other diseases
What medication should be given in severe pain after trauma?
Morphine (+ paracetamol).
Ibuprofen - bottom of pain ladder (and NSAID)
Tramadol - middle of pain ladder
NSAIDS - should not be used after severe trauma to begin with because they increase the risk of bleeding.
