Pain and its management

Question 1

basic pain pathway

Answer 1

cortex-thalamus-spinal cord-peripheral nerve-injury

Question 2

Nociceptors

Answer 2

• bare nerve endings
• most in skin and some in deeper tissue
• most are non-specific

Question 3

2 types of pain

Answer 3

fast response 
-Adelta fibres
-large myelinated up to 10m/sac
-sharp stabbing pain 
slow response
-C fibres 
-small unmyelinated 
-1.2 m/sec
-aching burning pain

Question 4

Local anaesthetics

Answer 4

bases-proton acceptors
mechanism:
-LA administered extracellularly in ionised form
-LA becomes unionised to cross membrane
-LA works intracellularly in ionised form to prevent Na+ channels opening

Question 5

NSAIDS

Answer 5

Prostaglandins
-part of the eicosanoid system
PGE2-pain sensitisation,renal arteriole dilation, ductus arteriosus patency

Question 6

COX-2

Answer 6

responsive

• inflammation
• hyperalgesia

Question 7

NSAIDS-cox inhibitors

Answer 7

eg aspirin, ibuprofen,parecetamol

Question 8

Opioid Receptors

Answer 8

sites:brain, spinal cord ,GI tract
peripherally in response to injury-G-protei n linked
-cellular hyper-polarisation