Pain Flashcards
McCaffery defined pain as
as
“whatever the experiencing patient
says it is and exists whenever he
says it does.”
The International Association for the
Study of Pain (IASP) has defined
pain as
The International Association for the
Study of Pain (IASP) has defined
pain as
Three things we think about when we think about pain
Duration
Acute or Chronic
Source of Pain
Classifications of pain
Cancer related, nociceptive, neuropathic, visceral, somatic, headache, the generalized pain of fibromyalgia, etc
Pain involves the interactions of three
major systems:
Sensory/discriminative system
• Motivational/affective system
• Cognitive/evaluative system
Pain threshold
The point at which that stimulus is experienced as
pain
• Differs from person to person
Pain tolerance
The duration of time or the intensity of pain that a
person will endure before taking overt action to
relieve the pain
• Decreases with repeated exposure to pain
• Decreased by fatigue, anger, fear, and sleep
deprivation
Neurological basis of Pain
Anatomy
• Afferent pathways
• Efferent pathways
• Physiology
• Tissue injury results in the production of arachidonic acid.
• Cyclooxygenase (COX) is needed to produce
prostaglandins.
• Prostaglandins lead to stimulation of nociceptors.
• Neuropeptides are associated with local pain and
inflammation.
• Norepinephrine and serotonin modulate pain in the
medulla and the pons.
Efferent pathways are responsible for
modulating the sensation of pain
Enodorphins are
inhibit neuropeptides and acts as body’s natural pain killer
Endorphine facts - 5 facts
Attach to the opiate receptors in the spinal
cord and brain
• Inhibit the release of neuropeptides
• Opioid agonists: are exogenous opiates
• Opiate receptors in the hypothalamus
• Certain activities increase circulating
endorphins
opioid recptors
Mu
Kappa
Delta
Mu
Analgesic
• Euphoria
• Respiratory depression
• Physical dependence
Kappa
Analgesic
Sedation
Delta
Less analgesic
• Emotional and affective components of the pain experience
• Physical dependence
Delta have important
Emotional and affective components of the pain experience
Sigma
Technically no longer considered opioid receptors. Have psychomemitic effects. Produce dysphroa. PCP works on this
Acute pain
less than 6 months duration
Acute somatic
arises from connective tissue, muscle, bone, and skin
Acute visceral
pain in the interanal organs and abdomen
Referred pain
pain that is present in an area distant from its point of origin
Acute somatic pain responds well to
acetaminophin, opoids, corticostroids, nsaid, local anthethics, ice and massage
Acute visceral pain responds well to
opoids
Chronic Pain
3 to 6 months OR beyond expected period of healing
Chronic Pain is centrally located and can be
Non-neuropathic pain
• Neuropathic pain
• Psychogenic pain
pure opioid agonists exampels
morphone and codeine
mixed opioid agonist example Mu
buprenorphine
mixed opioid agonists example kappa
pentazocine
butorphanol
pure opioid antagonist
naloxone
Purue opoid agonists work on
mu and kappa
Mu effects
analgeisa decreased GI motility respiratory depression sedation dependence
kappa effects
analgesia
decreased GI motility
sedation
opoid agonists work
centrally to relieve pain
opoid agonists bind to
opioid receptors, produce multiple responses
throughout the body.
Moderate to serve pain what is 1st line
opoid
Opoids can supress and slow what
Suppress cough, slow motility of the GI tract
Adverse effect with opoids
Adverse effect: n/v, constipation, sedation and respiratory
depression*
Schedule II opoid examples
Schedule II opioids - fentanyl, hydromorphone,
methadone, morphine, oxycodone, and oxymorphone.
Opioid Antagonists
• Blockers of opioid activity
• Reversal agents
• Naloxone (Narcan)
• Over-sedation and respiratory depression/arrest
• Opioid antagonists can be provided in combo with
opioids for patients with respiratory ailments
Opioids with Mixed Agonist-Antagonist Activity*
Stimulate opioid receptor; withdrawal symptoms or
adverse effects are not as intense due to partial activity of
receptor subtypes
Opioids can be combined with
non-narcotic analgesics (synergistically)
Examples of opioid mixed agonists-antagonist activity
Buprenorphine
