Pain and Analgesia Flashcards
(40 cards)
define chronic pain
lasting longer than 1 month,a ssociated with a p wide range of often subtle behaviourl disturbance
What are the 3 separate processes assocated with pain?
- nociception (sensory stimulus transmitted to the brain)
- perception (in CNS)
- behavioural reponse (varies according to species)
Define pain in animals
- aversive sensory and emotional experince
- awareness by the animal of demage or threat to the integrity of isssues
- changes the animals physiology and behaviour to reduce/avoid damage, v lieklihood of recurrence and promote recovery
What is hyperalgesia? Allodynia?
- increased sensitivity to nociceptive stimuli
- nociceptive sensatino of a NONPAINFUL stimulus
Clinical implicationd of hypersensitisation? What is this also known as? Which receptor is invovled and which drug can combat this?
- level of pain percieved is more severe
- anagesia less effective if given once pain present
- one type of analgesia may not be effectiveo nits own
= “wind up” d/t NMDA receptor involvement (ketmaine antagonist here)
Egs. of pain assessment
- NRS
- VAS
- SDS (no pain -> worst imaginable)
- Composite SS
- multidimensional scoring system
What is pre-emptive analgesia?
- administration of analgesics prior to onset of noxious stimuli (premed etc.)
Outline neural pathway of pain
- nociception
- mediated by substance P and glutamate
- synapse dorsal horn
- decussate
- travel in spinothalamic tract -> thalamus
[modulation within SC] - thalamocoritcal projections to the cortex
egs. of systeic analgesia
- opiods
- NSAIDs
- ketamine
- lidocaine
- a2 agonists
- tramadol (cheap, oral, lic)
- gabapentin/pregabalin
egs. local analgesia
- local anaesthetics
- opioids
- a2 agonists
define opium
- mixture of alkaloids from the poppy plant
define opioid
any natural occouring, semi-sythetic or synthetic compound that binds to opioid receptros and shares the properties of the natural ocourring endogenous opioids
Define opiate
- any naturally occourring opioid, derived rom opium eg. morphine, codeine
define narcotic
“to numb”
- was ued to deonte opioid, also describes non-opioid drugs of addictino
3 classifications of opioids?
> naturally occourring ocmpounds - morphine - codeine > semi-sythetic compounds - dimorphine (heroin) - dihydromorphone - buprenorphine - hydro-morphone > synthetic - pethidine - methadone - fentanyl, alfentanil, remifentanil - butorphanol, tramadol
What effects are mediated by each opioid receptors? LOOK UP and print table
delta: (DOP)
- spinal and supraspinal analgesia
- reduce gastric motility
kappa: KOP)
- spinal analgesia
- diuresis
- dysphoria
- species dependant (birds ^ no)
mu:
- analgesia, sedation, bradycardia , resp depression
- inhibition of GI transit, opioid tolerance…
n:
What is the only validated pain scale fro use in dogs?
Glasgow pain scale
What is an intervention score?
Pain scale sscore above which pain releif is administered
Which opioids are full m-agonists?
- morphine
- methadone
- pethidine (LIC)
- fentanyl/remifentanil
- etorphine (immobilon)
- papaveretum (omnopon)
Which drug is a partial m-agonist?
buprenorphine (LIC)
Which drug i a mixed agonist and antagonist?
- butorphanol (LIC)
Which pain scals have been validated in horses?
- composite orthopeadic pain cale
- PASPAS
Which drug are opioid antagonists?
- naloxone
- diprenorphine (revivon)
What is a partial agonist? eg?
- same overal actions of an agonist
- does NOT Produce maximal effect
- eg. buprenorphine
- partial m agonist
- analgesia, not as profound as full agonist
- (use milkd - mod pain)
