pain control

  1. pain
    • is a warning signal, protection
    • is a perception that arises from te activation of nociceptive receptors
  2. acute pain
    • readily identifiable stimulus
    • short duration high intensity
    • not real difficult to treat
  3. chronic pain
    • present past the normal time frame required for healing
    • long duration low intensity
    • difficult to treat
  4. A-alpha
    • motor nerves
    • large myelinated axons
    • fast transmission
  5. A-beta
    • sensory nerves
    • medium to large myelinated axons
    • relatively fast transmission
  6. A-delta
    • sharp localized pain
    • small lightly myleniated axons
    • relatively slow transmission
  7. C
    • generalized diffuse pain
    • small unmyelinated axons
    • slow transmission
  8. first order
    • cell body in dorsal root ganglion
    • axon terminates in dorsal horn
  9. second order
    • cell body in dorsal horn
    • axon crosses and terminates in one of several places
    • VPL of thalmus (fast)
    • reticular formation or midline and intralaminar nuclei of thalmus (slow)
  10. third order
    cell body in VPL, reticluar formation, or midline and intralaminar of thalmus
  11. 2 modulator systems
    within CNS to regulate pain perception both exhibit their influences at the spinal cord level segmental and suprasegmental
  12. segmental
    • ascending or gate control
    • non-nociceptive afferent (A-beta) input supresses nociceptive transmission between 1 and 2 order pain neurons
    • reduction in net discharge of 2 order pain neurons closing the gate
  13. clinical relevance of segmental pain control
    • reduce pain w/o pharmacologic means
    • pain must be peripheral in orgin (not CNS)
    • treatment goal is to recruit as many A-beta fibers as possible from the region in which the pain is originating
    • onset of pain relief is generally rapid but carry over is short
  14. suprasegmental
    • descending or endogenous opiate
    • two levels
    • hormonal and neuronal
  15. hormonal
    periventricula grey matter of the hypothalmus and pitutary gland provide for hormonal pre and post synaptic inhibition of 2 order pain projection neurons (impact on dorsal horn region)
  16. neuronal
    • involves periaqueductal grey (midbrain region)
    • input from the ascending spinoreticular tract
    • PAG activate the descending inhibition pathway in the DLF and VLF
    • fibers of DLF and VLF provide for pre and post synaptic inhibition of 2 order pain projection neurons
    • endogenous serve as neurotransmitters in this system
  17. clinicla relvance of suprasegmental pain control
    • can reduce pain w/o pharmacologic means
    • recruit A-delta and C fibers these do not have to be from the same area as the region
    • onset of pain os generally delayed but carry over is longer
  18. assessment of pain
    • pain drawing- fillled by physician or pt, reliability/validity are very questionable
    • rating scales- reliabilty is reasonable and validity is questionable
    • questionaires- mcgill pain, SIP, SP-36, Oswestry (low back pain) reliabilty and validity are reasonably good
Card Set
pain control
pain control