Pain management

1. Thangamani ramalingam
PT, MSc(PSY),PGDRM, MIAP

2. syllabus
Pain psychology (briefly) [2 Hours]
a) Define pain, physiology of pain
b) psycho – social factors of pain
c) pain management (Psychological methods)

3. Pain
 “An unpleasant sensory and emotional
experience associated with actual or
potential tissue damage, or described in
terms of such damage” ISAP (1979)
 One of the most common health problems
that causes people to seek medical attention
 Pain is actually beneficial to long-term health
and survival

4. DEFINITION
 Pain is a noxious unwanted perception in which
the patient seeks medical intervention.
 “Pain is subjective, individual and modified by
degrees of attention, emotional state and the
conditioning of past experiences.” (Livingstone
1943). The intensity of the pain is not directly
proportional to the degree of suffering.
Because it is basically a psychological
experience and depends on how it is
interpreted or experienced

5. TYPES
 Acute pain – shorter duration up to six months
 Acute monophonic pain
 Recurrent acute non-malignant pain
 Chronic pain – longer duration > six months
 Chronic malignant pain - progressive
 Intractable-benign
 Chronic pain associated with non-malignancy disease – identifiable
pathology
 Chronic non-malignant pain syndrome
 Recurrent acute – migraine
 Chronic and acute pain may have different causes – behavioral
factors may be involved in acute pain

6. PAIN RECEPTORS

7. PHYSIOLOGY OF PAIN
Influenced
by Limbic
system &
Reticular
formation

8. Gate Control Theory
 Gate control theory –Melzack & Wall (1965)
severity of pain sensation determined by balance between excitatory and
inhibitory inputs to T cells in spinal cord
 C & A-delta nociceptor afferents give excitatory input to dorsal root
ganglion of spinal cord– A-delta (myelinated) about 40 mph and C fibers
(unmyelinated) about 3 mph, other sensory information travels at about
180 -240 mph
 Substantia gelatinosa, large diameter A-beta non-nociceptor afferents
give inhibitory input
 Increased firing of non-nociceptor afferents causes presynaptic inhibition
of T cells and the spinal gate from excitatory cells to the brain is closed. –
 Physical agent modalities and physical activities believed to close the gate
by activating the non-nociceptor afferents

9. Central Control Mechanisms of Pain

10. Theories of pain
 Pain gate theory (Melzack& Wall)
 Pattern theory (Sinclair)
 Chemical theory (Neurotransmitters) (Encephalin /β-
endorphins)
 Descending control theory (PAG /Raphe nucleus
Inhibition)
 Substance ‘P’ levels
 Serotonin levels
 Central Control Mechanisms (by brain)
 Specific theory (Unique theory)

11. The same part of the
brain – the anterior
cingulate cortex –
responds to physical
and emotional pain.
Pain in the brain

12. Chemical processes involved in pain
 Substance P
Chemical mediator thought to be
involved with transmission of pain.
Associated with inflammatory pain
It excites pain transmitting neurons
when released
Its mechanism is not fully
understood
 Glutamate – release affects
amount of pain experienced
 Prostaglandins, bradykinin –
released when tissue damaged

13. Chemical processes involved in pain Endorphins
 Pain perception modulated by these opiate like
neurotransmitters
 The endorphins bind to certain sites on the nervous system
including peripheral nerves
 They suppress pain transmission at the spinal cord level by
inhibiting the release of the neurotransmitter gamma
aminobutyric acid (GABA) in the periaqueductal gray matter
(PAGM) and raphe nucleus of the brain
 High concentration of opiate receptors in limbic area of brain
explains the stress relief and euphoria associated with opiates
 Limbic system involved with emotional component of pain

14. Pain assessment
Physiological measures
EMG – muscle tension
Heart rate
Skin temperature
EEG and brain imaging
Behavioral pain measures
Physical symptoms
Clusters: guarding, bracing, rubbing, grimacing, and sighing
Symptoms can be misrepresented: report and unobtrusive
observation differences – Kremer et al. (1981)
Self-report measures

15. McGill Pain
Questionnaire
- sensations
- feelings
- intensity

16. Pain Rating Scales
Visual Analog Scale(VAS)
Graphic Rating Scale(GRS)
Simple Descriptor Scale(SDS)
Numerical Rating Scale(NRS)
Faces Rating Scale(FRS)

17. Pain Rating Scales
Pain
Discomfort
Scale

18. Chronic)
Injury / Insult
Treatment
Failure of Treatment
Loss of Control
Dependence
Reliance on Medication
Pain
Psychological
& Social
Consequences
Adapted from Gill (1997)
Pain Cycle

19. FACTORS AFFECTING PAIN
 Physical Factors:
• Pain tolerance
• Body constitution / Genetics
• Age
• Sex
• Temperature
• Climate (Humidity, Cold, Winter)
• Light, darkness
• Noise level
• Avoidance of physical activity
 Social Factors:
• Relationship with family • Social Norms
• Politico-Judicial Factors • Cultural effects (occupation,
• Social interactions • Hobbies
 Psychological Factors:
• Personality (Introvert / Extrovert)
• Social Context or role (e.g. –
Soldier vs Civilian)
• Attention
• Ecstasy
• Attitudes, past experiences •
Anxiety / Depression
• Learning / Memory (Education)
• Dependency / Conditioning
• Avoidance behavior
• Judgment, Ego, Expectation

20. Psychological factors
Learning
modeling
secondary gain
financial
culture
Personality
anxiety and depressive disorders
extroversion is associated with higher
pain thresholds
internal locus of control is associated
with better coping
Cognition
anticipation of pain is often
worse than pain itself
expectations of their ability to
cope
coping strategies
Stress

22. Sixteen Pain Behaviors
 Asymmetry
 Slow response time
 Guarded movement
 Limping
 Bracing
 Personal contact
 Position shifts
 Partial movement
 Absence of movement
 Eye movement
 Grimacing
 Quality of speech
 Pain statements
 Limitation statements
 Sounds
 Pain relief devices
(under use)

23. Physical methods for controlling pain

24. Medications
Opioid analgesics: substance
P release into dorsal horn
regulated by endogenous
endorphins and exogenous
opioids.

Inhibit substance P release

25. Medications
Morphine
OxyContin
Synthetics opiates
Local anesthetics

26. Medications
NSAID’s - Non-steroidal anti-
inflammatory drugs
Aspirin, ibuprofen, naproxen,
phenylbutazone, ketoprofen,
diclofenac
Acetaminophen (Tylenol)
has analgesic and antipyretic (fever
reducing) effect, but no anti-
inflammatory effect

27. Surgery
muscle/ nerve repair

28. Physical methods
Physical therapy
Exercise
Counter irritation – irritating body tissue to ease pain
Transcutaneous electrical nerve stimulation (TENS)
Acupuncture –
Massage therapy
Chiropractic therapy
.

29. Psychological methods for controlling pain
Hypnosis
Biofeedback
Relaxation and
distraction
Cognitive - Behavior
therapy
Behavioral Medicine

30. Behavioral/Cognitive Approaches
• Distraction
 Music and pain reduction –
Anderson et al. (1991)
• Relaxation
• Progressive technique
• Autogenic technique – use of self
instructions of warmth and
heaviness

31. Behavioral/Cognitive Approaches
• Guided Imagery
• Systematic
desensitization
• Reframing
• Meditation
• Stress management
techniques – not as
effective as other
techniques
• Thinking about the pain
and expectations

32. Placebo
Classical conditioning
Patient’s may change behaviors
Physiological changes which inhibit the
experience of pain