Pain Management Flashcards
What is a key functional difference between acute and chronic pain?
Acute = Signals tissue damage Chronic = No longer serves useful purpose (i.e. no tissue damage)
Which part of spinal cord do afferent pain signals go to?
Dorsal horn
Which neural pathways modulates pain?
Descending pathway (efferent)
What are 3 types of pain medications, with an example?
Non-opioids (e.g. paracetamol)
Adjuvants (e.g. steroids, anaesthetics)
Opioids (e.g. codeine)
What is step 1 of WHO analgesic ladder?
Non-opioid
?adjuvant
What is step 2 of WHO analgesic ladder?
Opioid for moderate pain
?non-opioid
?adjuvant
What is step 3 of WHO analgesic ladder?
Opioid for moderate/strong pain
?Non-opioid
?Adjuvant
In what context would a descending ladder of acute pain be used?
Surgery
What is paracetamol mode of action?
Uncertain!
Inhibition of nitric oxide generation via NMDA receptor
What are two subclasses of NSAIDs?
- Non-selective
- Selective COX2 inhibitors
What is NSAID MoA?
Arachidonic acid made following tissue injury with COX1/2. NSAIDs inhibit these, reducing inflammation/pain.
NB. Selective only inhibits COX2!
Common NSAID side effects?
- GI discomfort
- Prolonged bleeding
- Resp disorders
- Renal impairment
- Abnormal liver
- Increased MI/stroke
What is the MoA of opioids?
Work on opioid receptors.
Prevent transfer of pain message from PNS, preventing escalation to brain. Activate descending pathway.
Common opiate side effects?
- Poor GI motility
- Somnolence
- Respiratory depression
What are examples of adjuvants?
- Anticonvulsants
- Benzodiazepines
- Corticosteroids
- Adrenergic/Cholinergic Agonists
- NMDA receptor antagonists
