1. PAIN
.
PRESENTED BY- DR. SONAM RANI
GUIDED BY – DR.DEEPAK BALA
PRESENTED TO – Dr. VINITI GOEL (HOD)
DR. DEEPAK GROVER(PROFESSOR)
DR. DEEPAK BALA(READER)
DR. SARVANI , DR. VIKRAM, DR. MALTI
2. CONTENTS
• Introduction
• Classification
• Theories of pain
• Dual nature of pain
• Transduction Transmission
• Modulation
• Referred pain
• Pain assessment and management
• References
3. Definition:
DORLAND MEDICAL DICTIONARY DEFINED PAIN AS-
A more or less localized discomfort, distress or agony resulting from the
stimulation of specialized nerve endings.
MONHEIM DEFINED PAIN AS –
An unpleasant emotional experience usually stimulated by a noxious
stimulus and transmitted over a specialized neural network to the CNS
where it is interpreted as such.
REVISED INTERNATIONAL ASSOCIATION FOR THE STUDY OF PAIN (IASP)
DEFINITION OF PAIN (2020) AS-
• An unpleasant sensory and emotional experience associated with, or
resembling that associated with, actual or potential tissue damage.
6. According to pain intensity
a) Mild – Pain scale reading from 1-3
b) Moderate - Pain scale reading from 4-6
c) Severe- Pain scale reading from 7-10
Very Severe
7. According to temporal relationship
and duration
a) Intermittent.
b) Continuous.
c) Protracted.
d) Intractable.
e) Recurrent.
8. According to Qualities of pain
a) Steady pain.
b) Paroxysmal pain.
c) Bright pain.
d) Dull pain.
e) Itching.
g) Stinging.
h) Burning.
I) Throbbing.
j) Aching
9. According to onset
a) Spontaneous.
b) Induced.
c) Triggered.
According to pain localization
a) Localized.
b) Diffuse.
c) Radiating.
d) Lancinating.
e) Migrating.
10. Classification of pain based on
etiology:
Nociceptive pain
Nociceptive pain is experienced when an intact,
properly functioning nervous system sends signals
that tissues are damaged, requiring attention and
proper care.
• For example, the pain experienced following a cut
or broken bone alerts the person to avoid further
damage until it is properly healed.
• Once stabilized or healed, the pain goes away.
Nociceptive pain
Neuropathic pain
11. Nociceptive pain:
Somatic pain:
• This is the pain that is originating from the
skin, muscles, bone, or connective tissue.
• The sharp sensation of a paper cut or aching
of a sprained ankle are common examples of
somatic pain
12. Nociceptive pain:
Visceral pain:
• Visceral pain is pain that results from the
activation of nociceptors of the thoracic,
pelvic, or abdominal viscera (organs).
• Characterized by cramping, throbbing,
pressing, or aching qualities.
• Examples: labor pain, angina pectoris, or
irritable bowel.
13. Neuropathic pain
• Neuropathic pain
• Neuropathic pain is associated with damaged or
malfunctioning nerves due to illness, injury, or
undetermined reasons.
Examples:
• Diabetic peripheral neuropathy
• Phantom limb pain
• Spinal cord injury pain
14. Neuropathic pain
• It is usually chronic.
• it is described as burning, "electric-shock,"
and/or tingling, dull, and aching.
• Neuropathic pain tends to be difficult to treat.
• Neuropathic pain is of two types based on which
parts of the nervous system is damaged.
• 1. Peripheral Neuropathic Pain
• 2. Central Neuropathic Pain.
15. Neuropathic pain
Peripheral neuropathic pain:
• Due to damage to peripheral nervous system
• Eg: phantom limb pain
Central neuropathic pain:
• Results from malfunctioning nerves in the
central nervous system (CNS).
• Eg: spinal cord injury pain,
• Post-stroke pain.
16. THEORIES OF PAIN
• Specificity theory:
• Refers to a pain system based on a specific set
of peripheral nerve fibers that are nociceptive
in function.
• A –delta and C fibers are associated with two
qualities of pain, short latency pricking pain
and long latency burning pain respectively .
17.
18. Pattern theory
• Proposes that pain perception is based on
stimulus intensity and central summation.
• Pain is a result of the summation of a spatial
and temporal pattern of input.
19. Gate control theory
• Contains elements of both specificity and
pattern theories.
• Proposes a dorsal spinal gating mechanism in
the substantia gelatinosa that modulates
sensory input by the balance of activity of
small diameter (A-delta C) and large
diameter(A-beta) fibres.
21. DUAL NATURE OF PAIN
• First aspect, pain perception is the physio-anatomical process
whereby an impulse is generated, following application of an
adequate stimulus and is transmitted to the central nervous system.
• Second aspect, pain reaction, embraces extremely complex
neuroanatomical and psychological factors involving the cortex,
limbic system, hypothalamus and thalamus.
• A patient who is hypo reactive is considered to have high threshold
and a patient who has low threshold hyper reacts in response to
noxious stimulus.
22. • A- delta fibers function in the transmission of
first pain that is perceived as a sharp or bright
in quality and can be stimulated by chemical,
mechanical, or thermal stimulus.
• C fibers transmit second pain that is perceived
as dull pain . These fibers have smallest
diameter , slowest conduction velocity, and
highest threshold of activation
23. .
• FIELDS divided the processing of pain from the
stimulation of primary afferent nociceptors to the subjective
experience of pain into four steps:
TRANSDUCTION
TRANSMISSION
MODULATION
PERCEPTION
24. TRANSDUCTION
activation of the primary afferent nociceptor.
(thermal and mechanical stimuli, noxious
chemicals, and noxious cold, & Endogenous
inflammatory mediators producing
INFLAMMATORY SOUP)
Mediators interact with multiple receptors
expressed in nociceptors
Inducing their excitation
25. TRANSMISSION
the process by which peripheral nociceptive
information is relayed in the central nervous
system.
The primary afferent nociceptor synapses with
a second-order pain transmission neuron in the
dorsal horn of the spinal cord
where a new action potential heads toward
higher brain structures
26.
27. MODULATION
Modulation refers to mechanisms by which the
transmission of noxious information to the brain is
reduced.
Numerous descending inhibitory systems that originate
supraspinally and strongly influence spinal nociceptive
transmission exist.
The ascending nociceptive signal that synapses in the
midbrain area
activates the release of norepinephrine (NE) and
serotonin( two of the main neurotransmitters involved
in the descending inhibitory pathways.)
28. An endogenous opioid system for pain modulation also
exists.
Endogenous opioid peptides are naturally occurring pain-
dampening neurotransmitters and neuromodulators that
are implicated in pain suppression and modulation
They reduce nociceptive transmission by preventing the
release of the excitatory neurotransmitter substance P
from the primary afferent nerve terminal.
The presence of these natural opioid receptors for
endogenous opiates permits morphine-like drugs to
exert their analgesic effect.
30. REFERRED PAIN
• Pain may be referred from teeth to other
orofacial structures or it may be referred from
distant anatomic locations to teeth.
• Acute odontogenic pain has often a component
that is felt in one or more adjacent teeth of the
same arch, in teeth of opposite arch or in both
locations.
31.
32. REFERRED PAIN PATHWAY
• Referred pain from musculoskeletal and visceral
sources is usually deep, dull, aching and more
diffuse. The mechanism of referred pain is
enigmatic.
• 2 most popular theories are—
• Convergence projection theory
• Convergence facilitation theory
33. Convergence projection theory
• Primary afferent nociceptors from both
visceral and cutaneous neurons often converge
onto the same second order pain transmission
neurons in the spinal cord.
34. Convergence facilitation theory
• Nociceptive input from the deeper structures
causes the resting activity of second order pain
transmission neurons in the spinal cord to
increase or to be facilitated.
• Facilitation from deeper nociceptive impulses
causes the pain to be perceived in the area that
creates the normal, resting background
activity.
36. Pain Assessment
• Precipitating/Alleviating Factors:- What causes the
pain? What aggravates it? Has medication or treatment
worked in the past?
• Quality of Pain:- Ask the patient to describe the pain
using words like"sharp", dull, stabbing, burning“
• Radiation- Does pain exist in one location or radiate to
other areas?
• Severity- Have patient use a descriptive, numeric or
visual scale to rate the severity of pain.
• Timing- Is the pain constant or intermittent, when did
it begin.
37. Pain Assessment
• Assess for objective signs of pain:
• Facial expressions - facial grimacing (a facial
expression that usually suggests disgust or
pain), frowning (facial expression in which the
eyebrows are brought together, and the
forehead is wrinkled), sad face.
• Vocalizations - crying, moaning
• Body movements - guarding, resistance to
moving
40. Pain Assessment Tools
• Selecting a pain assessment tool should be, when possible,
a collaborative decision between patient and provider to
ensure that the patient is familiar with the tool.
Pain Scales
• Many pain intensity measures have been developed and
validated.
• Most measure only one aspect of pain (i.e, pain intensity)
and most use a numeric rating.
• Some tools measure both pain intensity and pain
unpleasantness and use a sliding scale that allows the
patient to identify small differences in intensity.
41. Pain Assessment Tools
• These are various tools that are designed to
assess the level of pain. The most commonly
used tools are:
• 1. Verbal Rating Scale
• 2. Numeric Rating Scale
• 3. Wong Baker's Faces Pain Scale
45. Pain Management
• Pain can be managed through:
1. Pharmacological Interventions
2. Non Pharmacological Interventions
46. Pharmacological Interventions
• Pharmacological therapy is given by using Analgesics.
• The analgesics may be NON OPIOIDS (NSAIDS) OR OPIODS
OR ADJUVANTS
• NSAIDS: Non steroidal anti inflammatory drugs
• Opioids: Opioids are medications that relieve pain. Derived
from opium.
• Adjuvants: Adjuvants are drugs originally developed to
treat conditions other than pain but also have analgesic
properties.
49. Pharmacological Interventions
• Nonopioids:- Used alone or in conjunction
With opioids for mild to moderate pain-Eg;
NSAIDS- paracetamol, aspirin.
• Opioids:-for moderate or severe pain- Eg:
morphine, codeine
50. • Adjuvants:- Used for analgesic reasons and for
sedation and reducing anxiety.-
-Eg:
• Tri-cyclic antidepressants
• Anti epileptics
• Cortico steroids
51. Non-Pharmacological Pain
Management
• For many individuals, the use of non-
pharmacologic methods enhances pain relief.
• These non-pharmacologic strategies are often
used in combination with medication.
