Exam 2: Pain Flashcards
What is pain?
a unpleasant multidimensional experience; sensory/emotional experience associated with actual or potential tissues damage
What factors can influence the actual pain reaction?
- anxiety
- culture
- past experiences
What is the #1 cause of longterm disability in America?
chronic pain
Who is chronic pain syndrome more common in?
women
5% of women between ages 18-65 experience headache:
15 or more days per month over the course of a year
__________ provides the CNS with info related to deep and superficial body structures
Somatosensory System
Somatosensory System information includes:
- temperature
- touch/pressure
- body position
- pain
What are the 3 different nerve fibers?
- A fibers
- B fibers
- C fibers
These fibers are:
▪ Myelinated, and has the fastest rate of conduction
▪ Conduct, pressure, hot/cold, touch information
▪ RELAY ACUTE PAIN
A fibers
How does A fiber pain feel?
well localized, sharp, stinging, pricking pain
These fibers are:
▪ Myelinated
▪ Transmit information from cutaneous and sub q receptors
B fibers
These fibers are:
▪ Unmyelinated
▪ Smallest diameter = slowest conduction
▪ Conduct warm/hot, mechanical & chemical sensation, and heat/cold induced pain
▪ RELAY CHRONIC PAIN
C fibers
How does C fiber pain feel?
diffusing pain that is dull, burning, and aching
There are 3 levels of neurons, the first order does what?
Detect sensation and transmit sensory info from periphery to the CNS (spinal cord)
There are 3 levels of neurons, the second order does what?
▪ Communicates with reflex responses and sensory pathways in the spinal cord and
travels directly to the brain
▪ The impulses travel from spinal cord to the brain
□ Into the thalamus & cerebellum
There are 3 levels of neurons, the third order does what?
▪ Relay from thalamus brain to the sensory cerebral cortex
▪ Sensation is process and…..
▪ Results in the feeling/interpretation of pain
Pain impulses go from the:
periphery > to the spinal cord > to the brain
Both parallel pathways carry info from the spinal cord to the thalamic region in the
brain, taking different routes but all ending up at the:
thalamus
This pathway is used for rapid transmission of sensory info and consists of large, myelinated fibers
Discriminative Pathways
This ascending pathway conveys pain, temperature & crude sense of touch
Anterolateral Pathways
Damage to the anterolateral pathway results in:
difficulty sensing pain &
temperature
This anterolateral pathways results in rapid transmission of sensory sensation using myelinated type A fibers to the thalamus
Neospinothalamic Tract
The neospinothalamic tracts pain is characterized as ________ and allows the patient to do what?
sharp, fast pain; locate & identify of the pain
This anterolateral pathways results in slow pain through unmyelinated type c fibers to the thalamus
Paleospinothalamic Tract
The paleospinothalamic tract is concerned with what kind of pain?
diffusing/dull-aching unpleasant sensations
The paleospinothalamic tract is commonly associated with what types of pain?
chronic pain & visceral pain
The paleospinothalamic tract activates part of the:
sleep/wake cycles (Reticular Activating System)
What is the purpose of pain?
it is an alarm system that warns of impending tissue injury, and forces the person to go seek help to fix the injury/pain
This theory regards pain as a separate sense and is evoked by the activity of receptors (nociceptors) that transmit special sense to pain centers
in the CNS where the pain is interpreted
specificity theory
In this theory pain signals are sent to the brain when stimuli come together in a specific pattern
Pattern Theory
In the pain theory, light touch is sensed as ______ whereas intense pressure is sensed as _______
touch; pain
In this theory pain impulses are felt when the gate (threshold) is opened at the spinal cord, in response
to an excess of nociceptive impulses and the gate is closed with interventions of nonpharm controls (pain isn’t felt)
Gate Control Theory
The Gate Control Theory can be hindered by _______ or increased by _______
stress; exercise
What is pain threshold?
the amount of stimulus required to elicit a pain response and the nociceptive stimulus is perceived as painful
In this theory the brain contains widely distributed neural network (thalamus, limbic system, somatosensory), which interpret multiple sensory inputs
Neuromatrix theory
This neuromatrix theory phenomenon occurs when pain is felt even when it is not there:
PHANTOM LIMB PAIN
Describe A fibers:
○ Large, myelinated, Fast, sharp pain
○ Release of glutamate at the synapse with the spinal neurons
○ ASSOCIATED WITH ACUTE PAIN
Describe C fibers:
○ Small, nonmyelinated = chronic, slow pain
○ Release glutamate and substance P
This pain is initiated by nociceptors in peripheral tissues when there is damage
Nociceptive Pain
This pain is direct injury or dysfunction of the sensory axons or peripheral/central nerves
Neuropathic Pain
What is pain tolerance?
Maximum intensity/duration of pain that a person is willing to endure before seeking
intervention
What are the different types of pain?
- cutaneous
- deep somatic
- visceral
- referred
This pain is easily localized, sharp in nature with burning qualities and occurs in the skin or subcutaneous tissues
cutaneous pain
This pain is more diffusing and radiating, occurring in the bones, muscles, tendons and joints
deep somatic pain
This pain is one of the most common pains from disease and occurs in the visceral organs
visceral pain
This pain originates in another place then diffuses to another place where it is perceived
referred pain
This pain is short-lived, and is resolved when the underlying cause is resolved (“self-limiting”)
acute pain
What is acute pain initiated by?
trauma, injury, surgery by activation of nociceptors
Initial injury causes ________, and then a secondary wave of intense acute pain results from ____________
nociceptive firing (hyperalgesia); secondary responses (inflammation, edema, etc.) –> can turn into chronic pain if not treated
Treating acute pain before it gets worse increases comfort for the patient and prevents:
hypersensitivity of pain centers in the periphery and CNS (also requires less drugs if treated early)
This pain serves no purpose and lasts longer than what is reasonably expected and is sustained by factors that are remote from the initial cause of the pain
chronic pain
What is the most common cause of chronic pain?
cancer
Chronic pain can be:
- unrelenting extreme pain (metastatic bone pain)
- continuous w/ periods of escalation (back pain)
What type of stress does chronic pain lead to?
- psychological
- physiological
- familial
- economical stress
What are the different levels of chronic pain sensations?
▪ Peripheral (Peripheral Sensitization)
▪ Peripheral (central)
▪ Central
This chronic pain sensation causes persistent stimulation of the peripheral nociceptors
and an inflammatory response increases the sensitivity of the C-Fibers
Peripheral (Peripheral Sensitization)
This chronic pain sensation causes abnormal function of the peripheral and central systems resulting from destruction of descending-inhibitory pathways (endogenous opioids) and the hyperexcitability/continuous firing of new nociceptors (phantom limb pain)
Peripheral (central)
This chronic pain sensation is due to a disease, injury, lesion of the CNS (MS)
Central
What factors does management of chronic pain depend on?
□ Cause of the pain
□ Underlying health problem
□ Life expectancy of the individual
Who is apart of the multidisciplinary team that manages pain?
- Anesthesiology, physicians, nurses, PT, surgeons, case management, etc.
What does the somatosensory unit consist of?
- cell body of the dorsal root
- ganglion neuron
- peripheral branch
- central axon
What does a neurometer test?
involvement of specific nerve fibers, allowing for a more comprehensive assessment of sensory function
Which level of neuron carries sensory information to the thalamus
second order
This mood tract is associated with mood altering emotions and attention narrowing effect of pain and can impact hypothalamic functions (HR and BP):
paleospinothalamic tract
What are dermatome maps for sensory impulses used for?
to find areas and determine level of nerve injury
________ is continued stimulus that is causing the pain
Hyperpathia
_______ is spontaneous, unpleasant sensation
Paresthesias
________ is distorted/abnormal sensations
Dysesthesia
________ is reduced pain sensation (nociceptors decrease along pain pathway)
Hypalgesia
_______ is absence of pain
Analgesia
_______ is pain after non-noxious stimulus
Allodynia
Hyperpathia is what kind of reaction?
Hypersensitive Reaction
How does paresthesia pain feel?
tingling/burning sensation of pins/needles
An example of dysesthesia would be the:
Dysfunction in the sense of touch such as in diabetic neuropathy where they can’t feel sensations and can’t feel pain
Where is dysesthesia most common on the body?
- skin
- scalp
- mouth
How does allodynia pain feel?
When a normal/non-painful stimulus causes stabbing/burning/sharp pain
Who suffers from allodynia pain?
- fibromyalgia
- neuropathies
What opioid/CNS depressant is used to relieve the sensation of pain and serves as an analgesic
morphine
What is meant by “wind-up”
an increase in pain over time
Describe the process of neurogenic inflammation
- tissue damage occurs
- inflammation of neurological tissue results in the release of inflammatory mediators (substance P) - once released, these Neuropeptides cause the release of Histamine from the Mast Cells (resulting in a inflammatory response)
- an inflammatory response occurs (redness, swelling, heat, tenderness, pain)
- this results in increase of substance P which starts the process over again (Ex: Migraine- Trigeminal Nerve stimulation results in inflammation… inflammation causes the severe pain)
What medication reduces the release of histamines
Antihistamines
What are the steps of neurogenic inflammation?
tissue damage > inflammatory mediators > stimulate nociceptors > impulses run up C fibers > dorsal nerve root reflex > inflammatory mediators move back down and are released into tissues > stimulation of nociceptors occur again
Nociceptive pain includes both:
somatic and visceral pain
Somatic pain contains both:
cutaneous and deep somatic pain
What are the causes of neuropathic pain?
- Pressure on the nerves (tumors)
- Physical/chemical injury to neuron
- Infxn of neuron
- Ischemia (lack of O2 in the tissues)
- Inflammation
Where does neuropathic pain originate?
from peripheral nerve injury or in diseases (includes widespread, unexplainable pain)
What are some examples of neuropathic pain conditions?
○ Trigeminal neuralgia
○ Postherpetic neuralgia
○ Phantom limb pain
What is phantom limb pain?
▪ Neuropathic pain following amputation of a body part and occurring soon after surgery (70% of amputees experience phantom limb pain)
How does phantom limb pain feel and how long does it last?
▪ Begins as tingling, cramping, shooting pain
- can go away, or continue to chronic pain
What gets trapped in scar tissue during phantom limb pain?
regenerating nerves
Where does referred pain for the heart occur?
- left jaw
- left side of chest
- left arm
Where does referred pain for the liver occur?
- right shoulders/clavicle
Where does referred pain for the gallbladder occur?
- upper right or mid abdomen
- upper right arm
How do you treat phantom limb pain?
- TENS (transcutaneous electrical nerve stimulation battery operated device used for pain. Electrodes are attached to the affected area and delivers small electrical impulses flooding the nervous system reducing pain signals to the brain –> produces endorphins)
- hypnosis
- relaxation training
- sympathetic blocks
What can headaches be an indicator of?
- meningitis
- brain tumors
- cerebral aneurysm
- post-trauma
- traumatic brain injury
Where is a TMJ headache located?
at temples, ahead of ears
Where is a sinus headache located?
at cheekbones above the eyes
Where is a cluster headache located?
around one eye
Where is a tension headache located?
squeezing around crown of head
Where is a neck headache located?
in back of head, top of neck
How does a migrane headache feel?
throbbing pain, nausea, vision changes, sensory sensitivity
When does pain begin and at what age can children remember and report pain?
neonatal period; 3 years old
How can you assess a child for pain?
using a numeric and picture scale
What physiological responses help to determine if a child is in pain?
▪ Crying
▪ Lack of playing
▪ Lack of eating
Does pain increase with age?
Yes
Unrelieved pain in older adults can:
- affect cognitive, emotion, and functional ability
- decrease QOL (appetite, decreased sleep quality)
When treating older adults for pain, which method should be used FIRST and why?
nonpharmacologic methods; because drug metabolism is impaired in adults
During an assessment for pain, what should you aim to do?
eliminate the cause of pain instead of treating the sxs
What are some examples of nonpharmacological interventions?
○ Cognitive behavioral interventions (relaxation) ○ Biofeedback ○ Distraction ○ Heat/cold therapy ○ TENS- electrical stimulation (STEM)
What are some examples of pharmacological interventions?
use of narcotic & nonnarcotic analgesics to manage pain
What do adjuvants do?
increase the effectiveness of other analgesics
Analgesics eliminate pain w/o effecting LOC but they do NOT:
cure the underlying cause ( USE ANALGESICS ONLY WHEN THEY ARE NEEDED TO PREVENT DEPENDENCY OR ADDICTION)
Examples of non-narcotic analgesics include?
▪ Aspirin & NSAID’s
▪ Acetaminophen
Aspirin & NSAID’s have what kind of effects? And what do they block?
antipyretic & anti-inflammatory effects that work by inhibiting the COX-enzymes
Acetaminophens are:
equal to NSAID’s WITHOUT an anti-inflammatory effect (only fever is reduced and pain is helped)
Examples of opioid analgesics include:
▪ Morphine & Codeine (Group of meds w/ Narcotic effects )
What does morphine & codeine work on in the CNS and what does it result in?
on the opioid receptors in the CNS; Provides analgesia, BUT also DEPRESSES THE RESPIRATORY EFFORT
What should you do before and after administration of opiods?
assess the pt respirations before and after administration
What is a side effect of opioids?
constipation due to decreased GIT motility
What type of pain does opioids treat?
acute and chronic
How/when should you give opioids?
Increase the analgesic effects if you give routinely & preemptively before pain gets too severe
What are the opioid receptors and where are they found?
Mu, delta and kappa; on the peripheral processes of primary afferent neurons and other CNS regions
Endogenous sources of analgesia include:
- enkephalins
- endorphins
- dynorphins
What receptor does morphine attach to?
Mu receptors
What functions as neurotransmitters and works to control pain?
Opioid peptides
Where are opioid receptors highly concentrated and what are they stimulated by?
in the gray area of the midbrain; stimulated by the PAG matter of the midbrain producing analgesia (analgesia system)
Your patient has been given morphine following major abdominal surgery. What effect will the morphine have?
analgesia
What OTC medication can cause liver and kidney failure?
Tylenol
How many americans die everyday from opioid overdose?
130
