*Pain Pathways (Exam II) Flashcards
What are the 2 components of pain?
- Sensory-discriminative
- Motivational-affective
S3
Differentiate the sensory-discriminative & motivational-affective aspects of pain.
- Sensory-discriminative - Ascending pathways and the perception of pain (location, intensity, sensation, etc.)
- Motivational affective - responses to painful stimuli (Ex. arousal, reflexes, endocrine responses, and emotional changes)
S3
What is nociception?
- The experience of pain through a series of complex neurophysiologic processes.
S4
Medication targets causes of pain through actions on 4 things
- transduction
- transmission
- modulation
- interpretation
in both PNS and CNS
S4
What is the % of Chronic pain in adult population
40 %
(8% - 37% low back pain)
S6
What are the four stages of pain perception?
- Transduction (tissue level)
- Transmission (via nerves)
- Modulation (via spinal cord)
- Perception (CNS)
S8
What is Transduction?
What 3 types of stimuli turns into action potential?
Nerve/electrical impulses/signals start at the nerve endings
Type of stimuli:
- mechanical
- chemical
- thermal
S9 and S10
What is Transmission?
Which nerve fibers are involved?
Travel of nerve/electrical impulses to the nerve body connecting to the dorsal horn of the spinal cord.
- A delta and C fibers
S9 and S10
What is Modulation?
Process of altering (inhibitory/excitatory) pain transmission mechanisms at the dorsal horn to the PNS and CNS.
S9
What is Perception?
What does it activate?
Thalamus acting as the central relay station for incoming pain signals & the primary somatosensory cortex serving for discrimination of specific sensory stimuli.
it activates descending inhibitory pain pathways and memory
S9 and S10
What drugs are used to affect the transduction of pain?
What specifically is being affected by these drugs?
- Local anesthetics & NSAIDs
- Peripheral nociceptors are affected
S10
What drugs are used to affect the transmission of pain?
What specifically is being affected by these drugs?
- Local anesthetics
- Αδ and C fibers
What drugs are used to affect the modulation of pain?
What specifically is being affected by these drugs?
- LA’s, opioids, ketamine, α2 agonists
- Afferent fibers of the dorsal horn
S10
What drugs are used to affect the perception of pain?
What specifically is being affected by these drugs?
-
General anesthetics, opioids, α2 agonists
-Brain
S10
Where does the modulation of pain impulses occur?
Dorsal horn of the spinal cord
S12
Where are nociceptors located?
- Skin
- Muscles
- Joints
- Viscera
- Vasculature
S13
What characterizes afferent C-fibers?
- Unmyelinated
- Pain from heat (burning) & sustained pressure
- Slow (less than 2 m/s)
S14
What characterizes A fibers?
-Myelinated
- Type I: Aβ & Aδ (heat,mechanical, chemical)
- Type II: Aδ (heat)
- Fast (>2 m/s)
S14
What chemical mediators of pain are targeted with spinal anesthetics?
Peptides
- Bradykinin
- Calcitonin
- CGRP
- Substance P
S15 NEED TO MEMORIZE THIS
Which chemical mediator is released first in response to injury?
Bradykinin
S15 NEED TO MEMORIZE THIS
What chemical mediators of pain are inhibited by NSAIDs?
Lipids
- Prostaglandins
- Thromboxanes
S15 NEED TO MEMORIZE THIS
What chemical mediators of pain are inhibited by cannabis?
Lipids
- Endocannabinoids
S15 NEED TO MEMORIZE THIS
What is sensitization?
- Decreased pain threshold (likely due to upregulation of receptors)
S18
↑ pain sensations to normally painful stimuli.
Hyperalgesia
S18
perception of pain to normally non-painful stimuli
Allodynia
S18
What characterizes primary hyperalgesia?
Hyperalgesia at original site of injury.
- Lower pain threshold
- increased response to suprathreshold stimuli
- Spontaneous pain
- Expansion of receptive field
S19