● Comfort and Pain Management
○ Physiologic effects of pain include hyperglycemia, increased cardiac workload,
immune system dysfunction, altered coagulation, GI ileus, urinary retention,
decreased lung volume, fatigue, increase HR, increase BP, increase RR,
increase muscle tension, pupil dilation
○ Respiratory effects
■ Decreased alveolar ventilation
■ Decreased vital capacity
○ Cardiovascular effects - even more stress on heart for cardio pts
■ Increased BP
■ Increased HR
■ Increased need for more O2
○ Neuro effects
■ Increased sensitivity to pain
○ GI effects
■ Decreased intestinal motility
■ Increased GI secretion
○ Musculoskeletal effects
■ Increased muscle spasm resulting in
■ Impaired muscle metabolism
○ Immune effects
■ Decreased immune function
○ Unrelenting/Unmanaged, severe, deep/visceral pain ** make sure to know
differences!!
■ Decreased HR, decreased BP, rapid, irregular breathing,
Nausea/vomiting, anxiety/agitation, decreased LOC (as norepinephrine,
serotonin, dopamine are depleted bc they are running out)
● Describing the Pain Experience
○ The Pain Process
■ Transduction
● Activation of pain receptors
● Conversion of painful stimuli into electrical impulses that travel
from the periphery to the spinal cord at the dorsal horn
● The nociceptors, or peripheral receptors, respond selectively to
mechanical, thermal, and chemical stimuli that are noxious
● It is believed that the injured tissue releases chemicals that excite
or activate nerve endings
● Other substances that are released that stimulate nociceptors: (do
not need to memorize these!!)
○ Bradykinin - powerful vasodilator that increases capillary
permeability and constricts smooth muscle, plays an
important role in the chemistry of pain at the site of an
injury even before the pain message gets to the brain.
, Releases histamine and produces redness, swelling, and
pain
○ Prostaglandins - send additional pain stimuli to CNS
○ Substance P - sensitizes receptors on nerves to feel pain
and also increases the rate of firing of nerves
■ Transmission of Pain Stimuli
● A-delta-fibers are larger and transmit acute, well-localized pain
that is typically elicited by mechanical or thermal stimuli
● C-fibers are smaller and transmit longer-lasting pain that is
triggered by chemical stimuli or persistent mechanical or thermal
stimuli
■ Perception of Pain
● Pain threshold - minimum intensity of pain
■ Modulation of Pain
● Sensation of pain is inhibited or modified
● Modified by neuromodulators
○ These are endogenous opioid compounds, naturally
present, morphine like chemical regulators in the spinal
cord and brain
● Endorphins - powerful pain blocking chemicals that have
prolonged analgesic effects and produce euphoria
○ Dynorphin has the most potent analgesic effect
● Enkephalins - reduce pain by inhibiting substance P from neurons
○ Less potent than endorphins, widespread through the brain
and dorsal horn of the spinal cord
■ The Gate Control Theory of Pain
● 1965 - Melzack and Wall
● Basically states that after you get hurt, you stimulate nerve
endings, but when you rub on it to make it try to hurt less, it may
seem that way bc you can only handle so much stimulation
○ Types of Pain
■ Duration of Pain
● Acute Pain
○ Rapid in onset, mild to severe intensity
○ Warns a person of tissue damage or organic disease and
triggers autonomic responses such as increased heart
rate, the fight-or-flight response, increased BP.. anxiety!!
○ After issue is resolved, acute pain disappears
○ Can last up to 6 months - cutoff!!**
● Chronic Pain
○ Lasts beyond the normal healing period
○ 6 months or longer
○ Varies greatly, unrelenting and severe, consistent with or
without periods of remission (disease is present, but the