Pain Management

Question 1

Types of Nociceptors

Answer 1

Mechanoreceptors
Silent nociceptors
Polymodal mechanoheat nociceptors

Question 2

Mechanonociceptors

Answer 2

respond to mechanical stimulation such as pressure, vibration, or movement (example: pinch and pinprick)

Question 3

Silent nociceptors

Answer 3

respond to inflammation

Question 4

Polymodal mechanoheat nociceptors

Answer 4

aka thermoreceptors – respond to extremes of temperature (>42 C and <18 C)

respond to excessive pressure and/or temperature

most prevalent

responds to excessive pressure and/or temperature

respond to alogens – pain producing substances or chemical mediators of pain

Question 5

Kinesthetic receptors

Answer 5

sense where limbs are located in space and movement

Question 6

Muscles spindles

Answer 6

sensory receptors located in muscles which sense tension

“stretch receptors”

Question 7

Sensation is often described as either

Answer 7

protopathic or epicritic

Question 8

Protopathic sensation

Answer 8

noxious (pain)

subserved by high-threshold receptors

conducted by smaller, lightly myelinated (A-delta) and unmyelinated (C) nerve fibers

Question 9

Epicritic sensation

Answer 9

nonnoxious

light touch, pressure, proprioception, and temperature discrimination

characterized by low-threshold receptors

generally conducted by large myelinated nerve fibers

Question 10

Threshold

Answer 10

the point that must be exceeded to begin producing a given effect or result or to elicit a response

with regard to low-threhold receptors (epicritic) or high-threshold receptors (protopathic), threshold is referred to as the action potential of the nerve cell
- protopathic sensations are considered to be cruder than epicritic sensations

Question 11

Which receptor (protopathic or epicritic) is more sensitive? Why?

Answer 11

Epicritic receptors are more sensitive than protopathic receptors because they sense more precise, light touch and have a low threshold to action potential. They require a lighter stimuli to evoke an action potential than that of protopathic receptors.

Protopathic receptors sense noxious pain and temperature and have a high threshold to action potential initiation. Protopathic receptors require more intense stimulation to evoke an action potential.

Question 12

Gate Theory of Pain

Answer 12

Pain transmission to the brain is blocked by “gates” located at the spinal cord level and the thalamus

These gates open or close, either allowing or blocking pain impulses from registering in the brain.