Pain physiology and assessment

Question 1

Define Pain

Answer 1

an unpleasant sensory and emotional experience arising from actual or potential tissue damage

Question 2

Define acute pain

Answer 2

the normal, predicted physiologic response to an adverse chemical, thermal, or mechanical stimulus. associated w/surgery, trauma, or acute illness

Question 3

What is the biologic purpose of acute pain?

Answer 3

alerts person to a noxious environment and activates fight/flight mechanisms

Question 4

Define chronic pain

Answer 4

Pain that persists or progresses over a long period of time and is resistant to medical treatments

Question 5

What is the biologic purpose of chronic pain?

Answer 5

no biological usefulness. becomes disease in its own right

Question 6

Define hyperalgesia

Answer 6

increased response to a stimulus that normally is painful

Question 7

Define hypoalgesia

Answer 7

diminished response to a normally painful stimulus

Question 8

Define analgesia

Answer 8

absence of pain in response to stimulation that normally is painful

Question 9

Define paresthesia

Answer 9

an abnormal sensation, whether spontaneous or evoked (pins/needles)

Question 10

Define allodynia

Answer 10

pain resulting from a stimulus such as light touch that doesn’t normally elicit pain

Question 11

What are the 4 physiologic processes associated with pain?

Answer 11

transduction, transmission, modulation, perception

Question 12

Describe the onset and quality of fast pain

Answer 12

felt within 0.1s, is sharp in character

Question 13

Describe the onset and quality of slow pain

Answer 13

begins after a second or more, is throbbing/aching in nature

Question 14

Describe characteristics of pain receptors and their stimulation

Answer 14

all pain receptors are free nerve endings. they do not adapt to the stimulus. can by stimulated by mechanical (stretch), thermal, or chemical factors

Question 15

What do prostaglandins and substance P do in relation to pain stimulation?

Answer 15

they enhance the sensitivity of pain endings but do not directly excite them

Question 16

What causes pain?

Answer 16

the rate of tissue damage

Question 17

What is the role of bradykinin in relation to pain?

Answer 17

causes the most pain and is the most responsible for causing the tissue damage type of pain.

Question 18

What are the two classifications of pain?

Answer 18

nociceptive or neuropathic

Question 19

Define nociceptive pain

Answer 19

involves the normal neural processing of pain that occurs when free nerve endings are activated by tissue damage or inflammation (somatic/visceral)

Question 20

Define neuropathic pain

Answer 20

involves the abnormal processing of stimuli from the PNS or CNS, and is thought to serve no useful purpose.

Question 21

What is an example of neuropathic pain?

Answer 21

peripheral neuropathy in diabetics

Question 22

Define transduction as a part of the pain pathway

Answer 22

The conversion of a noxious stimulus. Transferred into electrical activity in the peripheral terminals of nociceptor sensory fibers

Question 23

Define transmission as a part of the pain pathway

Answer 23

transmits info

Question 24

Define modulation as a part of the pain pathway

Answer 24

refers to the alteration (augmentation or suppression) of sensory input

Question 25

Define perception as a part of the pain pathway

Answer 25

refers to the decoding of afferent input into the brain that gives rise to the individual's specific sensory experience

Question 26

What type of fibers and tract transmit fast pain?

Answer 26

Type Adelta fibers, transmitted in the neospinothalamic tract

Question 27

What type of fibers and tract transmit slow pain?

Answer 27

Type C fibers, transmitted in the paleospinothalamic tract

Question 28

Describe 1st order neurons as a mechanism of pain

Answer 28

detect stimuli that threaten the integrity of innervated tissue. Get AP to dorsal horn

Question 29

Describe 2nd order neurons as a mechanism of pain

Answer 29

located in the spinal cord and process nociceptive info. Get AP to the brain

Question 30

Describe 3rd order neurons as a mechanism of pain

Answer 30

project pain info to the brain. Get AP to the cortex

Question 31

Where do fibers of the neospinothalamic tract terminate in the spinal cord?

Answer 31

can travel up or down 1-3 segments and terminate on neurons in the dorsal horn.

Question 32

What do fibers of the paleospinothalamic tract terminate in the spinal cord?

Answer 32

terminate in the laminae II or III of the spinal cord. they make 1-2 local connections before giving rise to 2nd order neurons

Question 33

What is the pathway of 2nd order neurons in both the neospinothalamic and paelospinothalamic tracts?

Answer 33

the 2nd order neurons cross to the opposite side and pass to the brain in the anterolateral columns

Question 34

Where do 2nd order neurons of the neospinothalamic tract terminate?

Answer 34

some terminate in the reticular substance, but most go to the ventrobasal complex of the thalamus

Question 35

Where do 2nd order neurons of the paleospinothalamic tract terminate?

Answer 35

some terminate in the thalamus, but most terminate diffusely in the reticular nuclei of the medulla, pons, mesencephalon, tectal area of the mesencephalon, or the periaqueductal gray region

Question 36

Where do the neurons go from the lower reticular areas of the paleospinothalamic tract?

Answer 36

project to the intralaminar nuclei of the thalamus, hypothalamus, and other basal brain regions

Question 37

How would the removal of the somatic sensory areas of the cortex affect pain?

Answer 37

still able to perceive pain because pain impulses to lower areas can cause conscious perception of pain

Question 38

What does the cortex determine with pain?

Answer 38

the quality of pain

Question 39

What do nerve fibers in the periventricular nucleus and periaqueductal gray nuclei secrete at their nerve endings?

Answer 39

enkephalin

Question 40

What do nerve fibers from the raphemagnus secrete at their nerve endings?

Answer 40

serotonin

Question 41

What does serotonin do in relation to pain suppression?

Answer 41

causes local neurons to secret enkephalin

Question 42

What is the fxn of enkephalin?

Answer 42

causes both pre- and post- synaptic inhibition of type C and type Adelta pain fibers where they synapse in the dorsal horns

Question 43

What are the three large molecules that opoid substances originate from?

Answer 43

proopoimelanocortin, proenkephalin, prodynorphin

Question 44

What are the major opiate substances?

Answer 44

B-endorphin, met-enkephalin, leu-enkephalin, dynorphin

Question 45

Where are the enkephalins and dynorphin found?

Answer 45

brain stem and spinal cord

Question 46

Where is B-endorphin found?

Answer 46

hypothalamus and the pituitary

Question 47

What is the fxn of the opiate system?

Answer 47

pain suppression during times of stress. an important part of an organism's response to an emergency is a reduction in the responsiveness to pain

Question 48

What are the different types of pain?

Answer 48

Cutaneous, somatic, visceral

Question 49

Describe cutaneous pain

Answer 49

superficial structures such as skin and subQ. sharp, bright pain, localized accurately

Question 50

Describe somatic pain

Answer 50

deep body structures, more diffuse than cutaneous, various stimuli (pressure on bone, ischemia to a muscle, tissue damage)

Question 51

Describe visceral pain

Answer 51

pain from an internal organ that's perceived to originate from a distant area. viscera have few sensory fibers except for pain fibers. highly localized damage to an organ may result in little pain, widespread damage can lead to severe pain

Question 52

Where is visceral (referred pain) localized to?

Answer 52

the dermatome of embryological origin

Question 53

What are causes of visceral pain?

Answer 53

ischemia, chemical irritation, spasm of hollow viscus, overdistension of hollow viscus

Question 54

Define pain threshold

Answer 54

closely associated with the pt at which a stimulus is perceived as painful

Question 55

Define pain tolerance

Answer 55

relates more to the total pain experience, it's the maximum intensity or duration of pain that a person is willing to endure

Question 56

How is inflammation related to pain?

Answer 56

It's used to promote healing. Sensitivity increased so that stimuli to the affected part that wouldn't normally cause pain now cause pain.

Question 57

What is the fxn of algogenic substances?

Answer 57

increases the permeability of capillaries and edema formation when a tissue is damaged/inflammed

Question 58

What is the biocultural model of pain?

Answer 58

society influences an individual's pain experiences

Question 59

What are the consequences of untreated acute pain?

Answer 59

increased metabolic rate and blood clotting, impaired immune fxn, negative emotions, and pain receptors become sensitive/long lasting changes