This document discusses chronic pain management. It defines chronic pain as pain that lasts months or years in any part of the body and can lead to depression, anxiety, and sleep issues. Chronic pain differs from acute pain in that it continues long after an injury heals. The document describes three types of chronic pain - neuropathic, somatic, and visceral - and their characteristics. It discusses evaluating and measuring pain, as well as pharmacological, physical, psychological, and invasive treatment methods for managing chronic pain. The goal of chronic pain treatment is to improve daily functioning and quality of life by decreasing pain and suffering through a multidisciplinary approach.

1. CHRONIC PAIN
MANAGEMENT
Dr. Radhwan Hazem Alkhashab
Consultant anaesthesia & ICU
2021

2. Introduction
Pain is defined by international association for study of
pain as “An unpleasant sensory and emotional
experience associated with actual or potential tissue
damage.
• Chronic pain last months or years and happens in all
parts of the body. It can lead to depression, anxiety and
trouble sleeping, which can make your pain worse.

3. Description of pain
Chronic pain differs from another type of pain called acute
pain. Acute pain happens when you get hurt, such as
experiencing a simple cut to your skin or a broken bone. It
doesn’t last long, and it goes away after your body heals
from whatever caused the pain. In contrast, chronic pain
continues long after you recover from an injury or illness.
Sometimes it even happens for no obvious reason.

4. Other Description of pain
1. Neuropathic pain.
2. Somatic pain.
3. Viesceral pain.
Neuropathic pain: caused by injury to the nervous
system either as a result of a tumor compressing nerves
or the spinal cord, or cancer actually infiltrating into the
nerves or spinal cord.

5. Somatic pain: caused by the activation of pain
receptors in either the cutaneous (the body surface) or
deeper tissues (musculoskeletal tissues).
Some chronic pain conditions displaying somatic pain
include:
 Fibromyalgia
 Tension headaches
 Pelvic pain caused by pelvic joint instability
 Chronic back pain that is not caused by nerve damage
 Arthritis

6. Visceral pain: pain that is caused by activation of pain
receptors from infiltration, compression, extension or
stretching of the thoracic, abdominal or pelvic viscera , e.g. :
 Irritable bowel syndrome
 Vulvodynia
 Bladder pain (such as cystitis)
 Endometriosis pain
 Prostate pain

7. Visceral pain is often described as generalized aching or
squeezing. It is caused by compression in and around the
organs, or by stretching of the abdominal cavity. People
with visceral pain may experience pallor, profuse sweating,
nausea, GI disturbances, and changes in body
temperature, blood pressure, and heart rate.
Sometimes visceral pain may radiate to other areas in the
body, making it even harder to pinpoint its exact location.
Anxiety and depression can reinforce visceral pain.

9.  Tissue damage following insults leads to the activation
of small nociceptive nerve endings and local
inflammatory cells. This chemical will produce pain
transduction via nociceptor stimulation as well as
facilitate pain transduction by increasing the excitability
of nociceptors.

10. Chemical mediators

11. Pain pathways

12. First order neurons : Nociceptive afferent fibers
terminate in spinal dorsal horn on the same side as
the dorsal root ganglion where primary sensory
neural cells are located.
Second order neurons:
First-order neurons synapse on second-order
neurons in the dorsal horn primarily within laminas I,
II, and V, where they release excitatory amino acids
and neuropeptides .

13. Modulation of pain
Modulation of pain occurs peripherally at the nociceptor, in
the spinal cord, and in supra- spinal structures. This
modulation can either inhibit (suppress) or facilitate
(intensify) pain.
At the spinal level modulation is via “Gate control theory”
by Melzack & Wall.

15. Gate control theory
Described physiological mechanism by which psychological
factors can affect the experience of pain.
Neural gate can open and close thereby modulating pain.
Gate is located in the spinal cord.

16. Condition that open the gate
 Physical conditions
Extent of injury
Inappropriate activity level
 Emotional conditions
Anxiety or worry
Tension
Depression
 Mental Conditions
Focusing on pain

17. Condition that close the gate
Physical conditions
 Medications
 Counter stimulation (e.g., heat, message)
Emotional conditions
 Positive emotions
 Relaxation, Rest
Mental conditions
 Intense concentration or distraction
 Involvement and interest in life activities

18. Chronic pain
The pain that continues a month or more beyond the
usual recovery period for an injury or illness or goes on for
months or years due to a chronic condition.
The pain may not be constant but disrupts daily life.It also
can interfere with sleep, keeping you awake a night.

19. Etiology of pain
Episodic pain syndromes:
 Headaches – migraine, tension, cluster…
 Ischemic episodes – claudication, angina, sickle cell
disease
 Visceral pain – biliary colic, irritable bowel,
premenstrual syndrome, renal Colic
 Somatic pain - gout

20. Cont.
 Neuralgia – an extremely painful condition consisting of
recurrent episodes of intense shooting or stabbing pain
along the course of the nerve.
 Causalgia – recurrent episodes of severe burning pain.
 Phantom limb pain – feelings of pain in a limb that is no
longer there and has no functioning nerves.

21. Medical evaluation
Location,onset.
Quality,radiation.
Response to previous treatments.
history of past, personal, social ,economic,
psychological and emotional status.
Plain radiographs, CT,MRI, bone scans.

22. Psychological evaluation
1. Clinical interview.
2. A structured pain inventory
a. Mc Gill pain questionnaire.
b. Psychosocial pain inventory.
c. Westhaven - Yale multidimensional pain inventory.
d. Pain profile.

23. Cont.
3. Psychometric testing:
a. Minnesota multiphasic pain inventory(MMPI)
b. Symptom check list-90.
c. Million behavioural pain inventory.
d. The beck depression inventory.
e. The spielberger state-trait anxiety scale.

24. Electromyography and Nerve conduction
studies:
Useful for confirming diagnosis of entrapment syndromes,
neural trauma and polyneuropathies ,radicular syndromes.
Can distinguish between neurogenic and myogenic
disorders.

25. Measurement of pain
Reliable quantitation of pain severity helps determine
therapeutic interventions and evaluate the efficacy of
treatments.
Pain scales :
- Numerical rating scale.
- Faces rating scale
- Visual analog scale.
- McGill pain questionnaire.

27. Management of chronic pain
Goals of treatment:
 Improvements in nociception, not curing.
 Decrease pain and suffering
 Increase daily activity.
 Instill hope

28. Therapeutic modalities
1. Pharmacological
2. Physical measures.
3. Psychological measures.
4. Invasive techniques.

29. Pharmacologic control of pain
About half of hospitalized patients who have
pain are under-medicated.
Medications are given as a prescribed schedule.
NSAIDS.
Opioids.
Antidepressants.
Anticonvulsants.
Sterods.
Local anaesthetics./ systemic administration.

30. NSAID
Traditional NSAIDs are effective in the treatment
of mild to moderate pain, but their use is limited
by potentially serious adverse effects
ketorolac : indicated only in the management of
moderately severe acute pain that requires opioid level
analgesics ; no more than 5 days.
COX-2 selective inhibitors e.g.[celecoxib (Celebrex),
rofecoxib (Vioxx). It`s 200-fold to 300-fold selectivity for
inhibition of COX-2 over COX-1

31. Opioids
Mentioned in acute pain management: e.g.
 Codeine
 Fentanyl
 Hydrocodone
 Hydormorphone
 Methadone
 Morphine
 Oxycodone
 Oxymorphone

32. Antidepressants
Antidepressants are effective agents in the treatment of
neuropathic pain.
Action due to blockade of presynaptic reuptake of
serotonin , norepinephrine or both. serious side effects ,
include anticholinergic effects including dry mouth,
confusion, and urinary retention .
E.g.Amitryptiline,Clomipramine,Doxepine,Fluoxetine
,Imipramine.

33. Antiepileptic drugs
Antiepileptic drugs have been used for many years in the
treatment of neuropathic pain particularly trigeminal
neuralgia and diabetic neuropathy.
Blocks voltage gated sodium channels and can suppress
spontaneous neuronal discharges.
e.g. phenytoin, carbamazepine, and valproic acid
The newer agents, gabapentin appears to be the most
effective and well tolerated

34. Neuroleptics
Useful in patients with marked agitation or psychotic
symptoms.
e.g. Fluphenazine,Haloperidol,Chlorpromazine and
perphenazine are commonly used.
Action due to blockade of dopaminergic receptors.

35. Corticosteroids
Glucocorticoids are extensively used in pain management
for their anti inflammatory and possibly analgesic
actions.Can be given topically,orally,parenterally.

36. Local Anaesthetics:
Lidocaine Infusion
More effective in neuropathic pain but can be used for all
pain syndromes. Starting dose 0.5mg-2 mg/kg per hr IV or
SC. Some studies demonstrate long-lasting pain relief
even after drug has been stopped. Need to decrease
opioids when starting.
Lidocaine Patch (Lidoderm®)
On 12hrs off 12 hours (but can leave on 24). Expensive
(great indigent program however)

37. Clonidin
Alpha adrenergic agonist.
Action – activation of descending inhibitory pathways.
Can be given epidurally ,intrathecally ,parenterally.

38. ketamin
N-methyl-D-aspartate receptor antagonist (NMDA)
Used as an anesthetic for years.
Case reports show effectiveness when traditional and
invasive techniques fail. Starting IV dose 150mg qd (0.1-
0.2mg/kg) with reduction of opioid achieved. Appears to
have a synergistic effect with opioids.

39. Physical therapy
Exercises :Graded exercise program prevents joint
stiffness,muscle atrophy and contractures.
Superficial heating modalities:
 Conductive :Hot packs, paraffin baths, fluido therapy.
 Convective
 Radiant.
Ultrasounds for deep pain.

40. Accupunctures :
Useful adjunct for patients with chronic musculoskeletal
disorders and headaches.
Technique – insertion of needles in discrete anatomically
defined points called “MERIDIANS”.

41. TENS ( transcutenous electrical nerve
stimulation)
Used widely in chronic pain
All available trials used TENS as an adjuvant to
medication, and it’s possible the effects of TENS was
masked by the a
nalgesic effect of medication

42. Physical therapy
 Ice packs
 Chiropractic/osteopathic manipulations
 Massage
 Yoga
 Topical agents (Ben Gay/Icy Hot – with menthol,
salcylates)
 Local injections (steroids, lidocaine)
 Glucosamine shown to help with osteoarthritis

43.  Herbals/supplements – glucosamine shown to be useful in
osteoarthritis, certain herbs like chamomile useful for colicky
pain
 Homeopathies/flower essences – for relaxation, visceral pain
 Healing touch/Reiki – using energy techniques, useful with
emotional components
 Neuro Emotional Technique – A chiropractic technique also
useful with emotional components
 Mind – focusing therapies:
• Meditation, yoga, guided-imagery, hypnosis, biofeedback
• Art/music/humor therapy, pet therapy
• By distraction, found to lower HR/RR and decrease pain up to
10-20%

44. Psychological therapy
Integral part of multidisciplinary approach to pain
management.
1. Self management techniques – cognitive Methods ,
relaxation, biofeedback.
2. Operant techniques.
3. Group therapy.

45. Cognitive methods:
Based on assumptions that a patients attitude towards
pain can influence the perception of pain.
Maladaptive attitudes contribute to suffering and disability.
Patient is taught skills for coping with pain either
individually or in group therapy.

46. Biofeedback – provides biophysiological feedback to
patient about some bodily process the patient is unaware
of (e.g., forehead muscle tension).
Relaxation – systematic relaxation of the large muscle
groups.
Hypnosis – relaxation + suggestion + distraction +
altering the meaning of pain.

47. Operant / Behaviour therapy :Based on premise that
behaviour in patients with chronic pain is determined by
consequences of behaviour.
Positive reinforcers aggravate the pain,negative
reinforcers reduce pain behaviour.

48. Invasive techniques
Roles of invasive techniques:-
Intractable pain.
Intractable side effects.
Symptoms that persists despite carefully individualized
patient management

49. Selection of block:
Depends on
- Location of pain
- Its presumed mechanism
- Skills of treating physician.
 L.A ‘s can be applied locally, at peripheral
Nerve ,somatic plexus ,sympathetic ganglia or nerve root,
centrally in neuraxis.

50. Somatic nerve blocks:
- Trigeminal nerve blocks
- Cervical, thoracic,lumbar paravertebral blocks
- Facet blocks
- Trans sacral nerve blocks etc.

51. Somatic nerve blocks

52. Sympathetic blocks:
 Stellate ganlion block
 Celiac plexus block
 Thoracic, lumbar sympathetic chain block,etc.

53. Stellate ganlion block Celiac plexus block

54. Epidural injections:
Lumbar interlaminar epidural injections
Fluoroscopic injections
Transforaminal injections
Radiofrequency rhizotomy

55. Spinal injections
Therapeutic effects of spinal injections are a combination
of primary physiologic changes that result from the
procedure and the secondary results arising from the
enhanced pain control that allow other treatments.

56. Spinal cord stimulation
Also called dorsal columns stimulation.
 Produces analgesia by directly stimulating large
A beta fibers in dorsal columns of the spinal cord.
 Mechanism – activation of descending modulating
systems and inhibition of sympathetic outflow.

57. Indications
- Sympathetically mediated pain
- Spinal cord lesions
- Phantom limb pain
- Failed back surgery syndrome.
Technique: electrodes placed epidurally and
connected to an external generator.
Complications: infection, lead migration, lead breakage.

58. Intracerebral stimulation
Deep brain stimulation (DBS) may be used for intractable
cancer pain and rarely for intractable neuropathic pain of
nonmalignant origin.
- Electrodes are implanted stereotactically into
periaqueductal and periventricular gray areas for
nociceptive pain.
Complications: intracranial hemorrhage and infection.

59. Conclusion
Effective tools are available to help doctors evaluate pain
in their patients. Unrelieved pain should be treated just like
any other vital sign: with aggressive measures.
Effective therapies are available to treat pain. Use
guidelines to develop a rational plan to relieve pain.
Side effects are manageable. Anticipate side effects and
treat aggressively.
Addiction rarely occurs. Trust your patient when they
report pain. Tolerance and physical dependence can occur.
Plan and you will succeed.

60. Thank you
Any Q