2. Definition
Concepts associated with pain
Brief history
Classification
Physiology
Assessment
Clinical features
Management
Conclusion
References
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3. The word pain is derived from the Latin word Peone
and the Greek word Poine meaning penalty or
punishment
Pain is defined as an unpleasant sensory and
emotional experience associated with actual or
potential tissue damage, or described in terms of such
damage.
The International Association for the Study of Pain
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4. Important implications
Pain is physical and emotional experience, not all in
the body or all in the mind.
It is in response to actual or potential tissue damage,
so there may not be abnormal lab or radiographic
reports despite real pain.
Pain is described in terms of such damage.
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5. Pain is an unpleasant subjective experience that is the
net effect of a complex interaction of the ascending
and descending nervous systems involving
biochemical, physiologic, psychological and neocortical
processes
◦ Chisholm-Burns et al. 2008
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6. Pain threshold- least amount of stimuli that is needed
for a person to label sensation as pain.
Pain tolerance- maximum amount of painful stimuli
that a person is willing to withstand without seeking
avoidance of the pain or relief.
Hyperalgesia and Hyperpathia- used interchangeably
to denote heightened response to a painful stimuli.
Allodynia-non-painful stimuli produce pain
Dysesthesia- unpleasant abnormal sensation
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7. ARISTOTLE considered pain a feeling and classified it as
a passion of the soul, where the heart was the source
or processing centre of pain
DESCRATES, GALEN, VESALIUS postulated that pain
was a sensation in which brain played an important
role
In 19th century, MUELLER, VAN FREY, GOLDSCHEIDER
hypothesized the concepts of neuroreceptors,
nociceptors, and sensory input
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8. According to The American Pain Foundation, more
than 50 million people in the US suffer from chronic
pain.
An additional 25%, 20 million experience acute pain
from injury or surgery
The National Institute for Occupational Safety and
health estimated that the cost of low back pain alone
was between 50 billions – 100 billions per year
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11. Acute pain
It lasts only through the expected recovery period
whether it has a sudden or slow onset and regardless
of intensity.
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12. Chronic pain
It begins when pain persists after the initial injury has
healed
It is a mild to severe, constant or recurring pain
without an anticipated or predictable end and a
duration of greater than 6 months. (Ackley & Ladwig,
2006)
It may be nociceptive, inflammatory, neuropathic or
functional in origin
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13. Chronic malignant pain
It occurs in 60-90 % of patients with cancer
It can be related to the tumour or cancer therapy or may
be idiosyncratic
Pain may also be found at the metastasized regions and
treatment interventions may activate peripheral
nociceptors
Pain can be somatic/visceral
Chronic non cancer pain
It is also referred to as chronic non – malignant pain
It may last for many years and is considered progressive in
nature
May be nociceptive, neuropathic or mixed in nature
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17. Classified using a standard
◦ 0(no pain) to 10 (worst possible pain) scale.
◦ Mild pain- rating of 1-3
◦ Moderate pain- rating of 4-6
◦ Severe pain- reaching 7-10 and is associated with worst
outcome.
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19. Somatic pain: Experienced when an intact, properly functioning
nervous system sends signals that tissue are damaged, requiring
attention and proper care.
Superficial: It is also known as cutaneous pain.
It arises from superficial structures such as skin & subcutaneous
tissues.
It is a sharp, bright pain with a burning quality and may be abrupt or
slow in onset
Deep: It originates in deep body structures such as periosteum,
muscles, tendons, joints & blood vessels. Radiation of pain from
original site of injury occur
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20. Visceral pain- a type of nociceptive pain that comes from the
internal organs
Unlike somatic pain it is harder to pinpoint
Pain is described as general aching or squeezing pain
It is caused by the activation of pain receptors in the chest,
abdomen, or pelvic areas
In cancer patients pain is caused by tumour infiltration,
constipation, radiation & chemotherapy
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21. Experienced by people with damaged or malfunctioning nerves. It is
described as
Aching
Throbbing
Burning
Shooting
Stinging
Tenderness/ sensitivity of skin
Peripheral neuropathic pain- follows damage and/or sensitization of
peripheral nerves.
Central neuropathic pain- results from malfunctioning nerves in
Central nervous system.
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23. Other types of pain
Sympathetically maintained pain-
occurs occasionally when abnormal connections between pain fibres
and the sympathetic nervous system perpetuate problems with both
the pain and sympathetically controlled function.
Breakthrough pain
Pain is intermittent, transitory & an increase in pain occurs at a
greater intensity
Usually lasts from minutes to hours and can interfere with functioning
and QOL. Eg. Neuropathic pain Lower back pain
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24. Referred pain
Pain that is perceived at
the site different from
its point of origin but
innervated by the same
spinal segment
Usually applies to pain
that originates from the
viscera Eg. MI
commonly is referred to
the left arm, neck &
chest
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25. Pain theories
◦ Pain theories are proposed to offer the possible physiologic
mechanisms involved in pain.
◦ They are as follows
Specificity theory
Pattern theory
Neuromatrix theory
Gate control theory
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26. Specificity Theory:
This theory states pain as separate modality evoked by
specific receptors that transmit information to pain centers or
regions in the forebrain where pain is experienced.
Pattern Theory:
Pain receptors share endings or pathways with other sensory
modalities but different patterns of activity of the same
neurons can be used to signal painful and non-painful stimuli.
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27. Neuromatrix Theory
▶ This theory was put forward by MELZACK
▶ This theory explains the role of brain in pain as well as the
multiple dimensions and determinants of pain
Gate Control Theory
▶ Proposed by MELZACK & WALL IN 1965
▶ According to this theory, the pain stimuli transmitted by
afferent pain fibres are blocked by GATE MECHANISM located
at the posterior gray horn of the spinal cord
▶ If the gate is open pain is felt, and if the gate is closed pain is
suppressed
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29. Nociceptors or pain receptors are sensory receptors
that are activated by noxious insults to peripheral
tissues
The receptive endings of the peripheral pain fibres are
free nerve endings
These receptive endings are widely distributed in the
◦ Skin
◦ Dental pulp
◦ Periosteum
◦ Meninges
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35. Transduction
◦ During this stage, noxious stimuli ( with potential to injure
tissue) trigger the release of biochemical mediators
(prostaglandins, bradykinin, serotonin, histamine, substance
P) that sensitize nociceptors.
◦ Noxious or painful stimulation also causes movement of ions
across cell membranes, which excites nociceptors.
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36. ◦ Pain medication can work during this phase by blocking the
production of prostaglandin(e.g., ibuprofen or aspirin) or by
decreasing the movements of ions across the cell membrane
(e.g., local anesthetic) . topical analgesic capsaicin (Zostrix)
depletes the accumulation of subtance P and blocks
transduction.
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37. Transmission
◦ Includes 3 segments.
◦ First segment- pain impulse travels from the peripheral nerve
fibres to the spinal cord.
◦ Second segment- transmission from the spinal cord and
ascension via spinothalamic tracts, to the brain stem and
thalamus.
◦ Third segment- involves transmission of signals between
thalamus to the somatic sensory cortex where pain
perception occurs.
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38. ◦ Pain control can take place during this second process. Opoids
(narcotic analgesics) block the release of neurotransmitters,
particularly substance P, which stops the pain at the spinal
level.
◦ Capsaicin may also deplete substance P that could inhibit the
transmission of pain signals.
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39. Modulation
◦ Often described as “descending System” Occurs when
neurons in the thalamus and brain stem send signals down to
the dorsal horn of the spinal cord.
◦ These descending fibres release substances such as
endogenous opoids, serotonin, and norepinephrine which can
inhibit the ascending noxious(painful) impulses in the dorsal
horn.
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40. Perception
◦ Is when the client becomes conscious of the pain.
◦ Pain perception is the sum of complex activities in the Central
Nervous System that may shape the character and intensity of
pain perceived and ascribe meaning to the pain.
The first three steps in nociception are important for the
sensory and discriminative aspects of pain.
The fourth step, perception, is integral to the subjective and
emotional experience.
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42. Method of pain assessment
◦ Comprehensive history intake
◦ Questioning on characteristic of pain – onset, duration,
location, quality, severity & intensity
◦ Physical exam
◦ Evaluation of psychological status
◦ The impact of pain on the patients functional status,
behaviour and psychological status should also be assessed
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43. Pain may be accompanied
by physiologic signs and
symptoms and there are
no reliable objective
markers of pain
The severity of pain can
be assessed by :
Rating scales
Provide a simple way to
classify the intensity of
pain and should be
selected based on the
patients ability to
communicate
Multidimensional scales
Helpful in obtaining
information about the
pain and impact on QOL,
but are more often time
consuming to complete
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50. General:
◦ Acute distress/ trauma pain
◦ No noticeable suffering (Chronic pain)
Symptoms:
◦ Sharp, dull, burning, shock like, tingling, shooting radiating,
fluctuating in intensity and varying in location
Non – specific: Anxiety, depression, fatigue, insomnia, anger
and fear
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51. Acute pain
Hypertension, tachycardia, diaphoresis, mydriasis, pallor
Chronic pain
There may be no obvious pain signs in some acute cases and
in most chronic/ persistent pain
Laboratory tests
Pain is always subjective i.e. there are no laboratory tests
It is diagnosed based on patients description and history
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52. Goals of therapy
◦ To decrease the subjective intensity
◦ To reduce the duration of the pain complaints
◦ To decrease the potential for conversion of acute pain to
chronic persistent pain syndromes
◦ To decrease the physiological, psychological, & socioeconomic
sequelae associated with under treatment of pain
◦ To minimize ADRs to pain management therapies
◦ Improving the patients QOL and the ability to perform
activities of daily living
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60. OPIUM is a raw extract of the poppy plant Papaver
somniferum
During 19th century, MORPHINE was isolated from
opium and its pharmacological effects were
characterized
Opiod receptors
Type characterization
◦ μ - MU Highly selective for opioids
◦ δ – DELTA Mixed agonist – antagonist response
◦ K - KAPPA
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63. ORGAN SYSTEM ADVERSE EFFECT MANAGEMENT
Central nervous
system
Analgesia
Dysphoria
Miosis
Physical dependence
Sedation
CNS irritability Reduce dose by 25% or increase the
dosing interval
Discontinue OPIOID, treat with
Benzodiazepines
VERTIGO MECLIZINE 12.5 – 25mg PO every 6
hours
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64. Respiratory system Respiratory depression MILD: Reduce dose by
25%
MODERATE – SEVERE:
NALOXONE 0.4 –
2mg IV every 2 – 3
minutes (up to
10mg)
0.1 – 0.2mg IV every
2 – 3 minutes until
desired
Reversal
CARDIOVASCULAR
SYSTEM
Decreased myocardial
O2 demand
Vasodilation
Hypotension
Gentiourinary system Increased bladder
sphincter tone
Urinary retention
Reassurance, bladder
massage , intermittent
urethral
catheterisation
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65. Gastrointestinal system Constipation CASANTHROL – DOCUSATE 1
capsule at bed time/ BD
SENNA 1 – 2 tablets at bed time/
BD
BISACODYL 5 – 10mg daily +
DOCUSATE 100mg BD
Nausea & Vomiting HYDROXYZINE 25 – 100mg
(PO/IM) every 4 – 6 hrs as
needed
DIPEHNHYDRAMINE 25 – 50mg
(PO/IM) every 6 hours
as needed
ONDANSETRON 4mg IV or 16mg
PO, 4 – 8mg IV every
8 hours as needed
PROCHLORPERAZINE 5 – 10mg
(PO/IM) every 3 – 4
hrs, 25mg/ rectum BD
Gastroparesis METOCLOPRAMIDE 10mg (PO/IV)
every 6 – 8 hours
Immune system
effects
Suppression of
function of natural
killer
cells (NK cells)
Cessation of treatment
or lower dosing.
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66. Neuroendocrine
effects
Inhibition of release of
leutinizing hormone
(LH)
Stimulation of release
of ADH & Prolactin
Cessation of treatment
or lower dosing.
Dermal effects Flushing
Pruritus
Urticaria
HYROXYZINE 25 –
100mg (PO/IM) every
6 hours as
needed
DIPHENHYDDRAMINE
25 – 50mg (PO/IM)
every 6
hours as needed
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68. ◦ Nonsteroidal Anti-inflammatory Drugs (NSAIDS) are usually
considered as Non Opioid Analgesics
CHARACTERISTICS FEATURES:
Relieve pain without interacting with opioid receptors
Possess anti – inflammatory properties
Have antiplatelet activities
Do not cause sedation & sleep
Are not addicting
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73. It a delivery system with which patients self-administer
predetermined doses of analgesic medication to relieve
their pain.
Was introduced in the early 1980s, the daily
management of postoperative pain has been extensively
optimized.
Advantages are:
◦ improved pain relief
◦ greater patient satisfaction
◦ less sedation
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74. All PCA modes contains
◦ initial loading dose,
◦ demand dose
◦ lockout interval
◦ background infusion rate
◦ 1-hour or 4-hour limits.
Morphine is the most
studied and most
commonly used
intravenous drug
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75. Although intravenous PCA is the most studied route of
PCA, alternative routes include
◦ use of peridural catheters
◦ peripheral nerve catheters
◦ Recently, transdermal PCA has been described.
The use of peripheral or neuraxial nerve blocks is
recommended to avoid the so called opioid tolerance
observed with the intravenous administration of
opioids.
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76. Non-pharmacological pain management is the
management of pain without medications.
This method utilizes ways to alter thoughts and focus
concentration to better manage and reduce pain.
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78. Prolonged bed rest in the treatment of patients with neck and
low back pain and associated disorders.
It supports immobilization with its deleterious effects on
bone, connective tissue, muscle, and psychosocial well-being.
For severe radicular symptoms, limited bed rest of less than
48 hours may be beneficial to allow for reduction of
significant muscle spasm brought on with upright activity.
Avoid resting with the head in a hyper flexed or extended
position.
The proactive approach emphasizes activity modification as
opposed to bed rest and immobilization.
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79. Manipulation and Mobilization
Manipulative treatment is commonly used in the treatment of
patients with neck pain and associated disorders.
◦ myofascial release
◦ muscle energy/contract-relax,
◦ high-velocity low-amplitude manipulation.
It has been shown to improve flexibility, decrease the
perception of pain and decrease the levels of stress
hormones.
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80. Traction
Cervical traction is a therapeutic modality that can be
administered with the patient in the supine or seated
position.
Traction may reduce neck pain by
◦ passive stretching of myofascial elements,
◦ gapping of facet joints
◦ improving neural foramina opening
◦ reducing cervical disc herniation.
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81. Reduces radicular symptoms in individuals with confirmed
radiculopathy, localized neck pain in individuals with
cervicogenic pain and spondylosis.
Cervical traction may be initiated during physical therapy with
the patient properly instructed in home use.
It is not a stand-alone treatment modality and should be done
in conjunction with range-of-motion (ROM) exercises,
appropriate strengthening, and correction of postural issues.
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82. Superficial Heat
Superficial heat can produce heating effects at a depth limited
to between 1 cm and 2 cm.
It has been found to be helpful in diminishing pain and
decreasing local muscle spasm.
Superficial heat, such as the hydrocollator pack
It should be used as an adjunct to facilitate an active exercise
program.
It is most often used during the acute phases of treatment
when the reduction of pain and inflammation are the primary
goals.
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83. Electrical Stimulation
High-voltage pulsed galvanic stimulation has been used in acute
neck pain to reduce muscle spasm and soft tissue edema.
It is commonly used despite the lack of hard scientific evidence
for its efficacy.
Its effect on muscle spasm and pain is thought to occur by its
counterirritant effect on nerve conduction and a reduction in
muscle contractility.
Its use should be limited to the initial stages of treatment, such
as the first week after injury, so that patients may quickly
progress to more active treatment that includes restoration of
ROM and strengthening.
Electrical stimulation often may be combined with ice or heat to
enhance its analgesic effects.
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84. Cryotherapy
Cryotherapy can be achieved through the use of ice, icepacks, or
continuously via adjustable cuffs attached to cold water
dispensers.
Intramuscular temperatures can be reduced by between 3 °C
and 7 °C, which functions to reduce local metabolism,
inflammation, and pain.
Cryotherapy works by decreasing nerve conduction velocity,
termed cold-induced neuropraxia, along pain fibers with a
reduction of the muscle spindle activity responsible for
mediating local muscle tone.
It is usually most effective in the acute phase of treatment,
though it can be used by patients after their physical therapy
sessions or their home exercise program to reduce pain and the
inflammatory response.
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85. Transcutaneous Electrical Nerve Stimulation
It has been used to treat patients with various pain
conditions, including neck and low back pain.
Factors dictating success include
◦ electrode placement
◦ chronicity of the problem
◦ previous modes of treatment.
TENS is generally used in chronic pain conditions and not
indicated in the initial management of acute cervical or
lumbar spine pain.
Overall, research is limited in regard to the isolated use
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86. CORDOTOMY: In the thoracic
region , the spinal cord opposite
to the side of pain is partially
cut to interrupt the anterolateral
pathway
THALAMOTOMY: Involves
causterization of specific pain
areas in the intrathalamic nuclei
in the thalamus, which often
relieves suffering type of pain
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87. Sympathectomy
Excision of the segment of the
sympathetic nerve or one or
more sympathetic ganglia
Rhizotomy
Surgical removal of spinal nerve
roots for the relief of pain or
spastic paralysis
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89. Pain management is faced with some barriers such as
◦ Attitude of healthcare providers or clients and knowledge
deficits. Clients may not report pain because they expect
nothing can be done.
◦ Fear of becoming addicted especially in long-term opioid
use
◦ Pseudo addiction- results from under treatment of pain
where clients may become focused on obtaining
medication.
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91. Way out may include
Acknowledge and accepting client’s pain.
Acknowledge possibility of pain, listen attentively and attend
to client’s need promptly.
Reduce misconceptions about pain.
Assisting support persons.
Reduce fear and prevent pain as much as possible
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