Heamo week 4 (pain) Flashcards
What is the broad definition of pain
An unpleasant sensory and emotional experience caused by actual or potential tissue damage
What is Nociception
This is a part of the pain that is mainly used to indicate to us that something might be harmful or going to be harmful to our bodies or tissues
It can be broken down onto 4 main stages
What is transduction
Transduction is the method of physical stimuli being converted into action potentials.
These are at the tip of the nocieptors or nociceptor receptors and can respond to physical , chemical or thermal
They are located at the end of A delta and C fibers
What is transmission
This is the stage where the action potential goes from the A delta and C fibers then travel to the dorsal horn up the spinal cord and into the different areas of the brain
What is perception
This is where the brain ‘decodes’ the action potential
Since many different areas of the brain can receive the impulse this is why pain is so complex and how it can affect different people in different ways
Why does referee pain happen
This happens because some of the A Delta Fibers and C fibers can converge at the same level in the spinal cord. E.g. The fiber for the arm can converge near the fiber for the heart (why you get arm pain in MI’s)
How are opidoids such good analgesics
These work by blocking the release of neurotransmitters such as glutamate and norepinephrine. These neurotranmitters are the ones that can fire action potentials, therefore causing that pain sensation
It also increases the amount of dopamine released therefore reducing the perception of pain
How does Ketamine work
It works by inhibiting NMDA receptors (blocks binding of glutamate) . At these receptors, there are massive amounts of excitatory neurotransmitters. Ketamine inhibits these neurotransmitters, therefore slowing down the action potentials that are firing
Should we give fenantyl and ketamine combined?
Yes if we pla on giving ketamine we should be giving fenantyl first
This is because giving fentanyl has that initial relief of pain, and ketamine on top of that will actually improve the effect of the fent
Droperidol
