Pain Physiology Flashcards
Pain Def
unpleasant sensory and emotional experience from actual or potential tissue damage
Eudynia Def
signal to body that it’s being damaged in some way that needs immediate attention.
Nociceptive Pain Def
normal neural processing pain that occurs when free nerve endings are activated by tissue damage or inflammation
ex. somatic, deep visceral
Neuropathic Pain Def
abnormal processing of stimuli from peripheral/CNS, thought to serve no useful purpose
Nociception Def
encoding and processing of harmful stimuli
Allodynia Def
pain resulting from a stimulus that does not normally cause pain
Paresthsia Def
abnormal sensation, spontaneous or evoked
Analgesia Def
absence of pain in response to stimuli that is normally painful
Hypogesia Def
diminished pain to a normally painful stimul
Hyperesthesia Def
excessive physical sensitivity
Hypoesthesia Def
reduced physical sensitivity
Pain Tolerance Def
total pain experience
maximum intensity/duration of pain that a person is willing to endure before they want something done about it.
Pain Threshold Def
the point at which a stimulus is perceived as painful
Differentiate between the following types of pain:
- cutaneous
- Deep somatic
- visceral(referred)
- phantom
- acute
- chronic
Cutaneous-
arises from superficial structures, sharp, bright pain, localized accurately
ex. paper cut
Deep Somatic-
deep body structures, more diffuse pain, periosteum, muscles, tendons, joints, blood vessels.
ex. sprained ankle
Visceral(referred)-
pain of internal organ that is perceived to originate from a distant area of the skin. low density of nociceptors in viscera,
visceral and somatic afferent neurons converge on same dorsal horn projection neurons making it difficult to identify origin of pain.
* referred pain- localized to the dermatome of embyological origin, ex: heart»>neck, shoulder, & arm
acute-
short duration, resolves when underlying pathological process has resolved. Alerts of actual or impending tissue damage.
Chronic-
pain that persists longer than reasonably expected after inciting event, is often resistant to medical treatments May continue for years and years
ex. migraine HA
Managing Acute Pain
aggressively managed and pain meds provided before pain becomes severe.
Phantom Limb Pain
neurologic pain following amputation
tingling, squeezing, heaviness, leading to burning, cramping, or shooting
Trace the transmission of pain signals
Initial tissue injury, NT released (prostaglandins, ACH, substance P) from tissues, recognized by nociceptors, nociceptor travels to dorsal horn and synapes onto 2nd order neuro to the thalamus via spinothalamic tract (neo- alpha/delta fast fibers sharp pain, fast withdrawl OR paleo-C fibers slow dull pain), synapses to 3rd order neuro and communicates w/ somatosensory cortex where pain is differentiated.
neospinothalamic- can be localized well
paleospinothalamic- poorly localized slow pain
4 physiologic processes associated w/ pain
Transduction - conversion of noxious stimulus into electric activity in peripheral terminals of nociceptors
Transmission- passage of AP from periphery along axons to central terminal of nociceptors in CNS
Modulation- alteration of sensory input
Perception- interpretation of the info to the brain, gives person the specified sensation
Endogenous Analgesic Mechanisms & How they relate to pain transmission
3 endogenous opioids- enkephalins, endorphins, dynorphins
inhibit Ca2+ channels in dorsal root and inhibit post synaptic transmission of pain impulses
