Transcript Nociceptive Pain

‫כאב‬
Silviu Brill MD
Director, Pain Medicine Center,
Tel Aviv-Sourasky Medical Center
PAIN - Epidemiology
“We don’t have a lot of statistics about pain, but
the ones we do have are frightening.”
Chronic pain is the most common cause of
disability, partially or totally disabling 50
million people in US
‘Chronic Pain in Europe’ Survey
(n=46,394)
__________________________________________________________________________
Overall Prevalence
Norway (n=2,018)
Poland (n=3,812)
Italy (n=3,849)
30%
27%
Germany (n=3,832)
Israel (n=2,244)
17%
17%
26%
Denmark (n=2,169)
16%
Belgium (n=2,451)
23%
Switzerland (n=2,083)
16%
Austria (n=2,004)
21%
France (n=3,846)
15%
Finland (n=2,004)
19%
Ireland (n=2,722)
13%
Sweden (n=2,563)
18%
UK (n=3,800)
13%
Netherlands (n=3,197)
18%
Spain (n=3,801)
11%
0%
100%
Breivik et al. Eur J Pain 2006;10(4):287-333.
0%
19%
100%
Effects of Chronic Pain
Physical Functioning
Ability to perform
activities of daily living
Sleep disturbance
Kinetophobia
Social Consequences
Relationships with
family and friends
Intimacy/sexual activity
Social isolation
Loss of work
Psychological
Morbidity
Depression
Anger, frustration
Loss of self-esteem
Anxiety
National
Consequences
Healthcare costs
Lost workdays
Disability
Overview
Definition
Acute vs. Chronic Pain
Nociceptive vs. Neuropathic Pain
Diagnostic
Pathophysiology
Treatment
‫הגדרת הכאב‬
‫‪INTERNATIONAL ASSOCIATION FOR‬‬
‫‪THE STUDY OF PAIN‬‬
‫כאב הוא חוויה תחושתית‬
‫ורגשית לא נעימה‬
‫שקשורה בנזק רקמתי‬
‫אמיתי או פוטנציאלי‪.‬‬
Classifications of Pain
Acute
Duration
Chronic
Nociceptive
Pathophysiology
Neuropathic
Insult
The Continuum of Pain
Time to resolution
Acute
Pain
Chronic
Pain
3-6 months
<1 month
• Usually obvious tissue damage
• Increased nervous system activity
• Pain resolves upon healing
• Serves a protective function
• Pain for 3-6 months or more
• Pain beyond expected period of
healing
• Usually has no protective function
• Degrades health and function
‫כאב כרוני לעומת כאב אקוטי‬
‫כאב כרוני‬
‫מחלה‬
‫ארוך טווח‬
‫אזעקת שווא‬
‫דיכאון‬
‫תגובה בעייתית לטיפול‬
‫גישה רב‪-‬תחומית‬
‫כאב אקוטי‬
‫סימפטום‬
‫קצר טווח‬
‫סימן אזהרה‬
‫חרדה‬
‫תגובה טובה לטיפול‬
‫טיפול יחיד‬
Types of Chronic Pain
Nociceptive Pain
Osteoarthritis Neuropathic Pain
Deg. Spine Dis. Diabetic neuropathy
Dysfunctional Pain
PHN
RA
Fibromyalgia
Polymyal. rheumTraumatic injury
Chronic headaches
MS
Pancreatitis
IBS
Post stroke pain
Burning mouth
synd.
Chronic Pain
… is not prolonged acute pain
… must be considered and treated as a
disease
“Pain is a more terrible lord of mankind
than even death himself”
Albert Schweitzer
Pain
Nociceptive
Neuropathic
Inflamatory
Ischemic
Idiopathic
IASP Definitions
Neuropathic pain
Pain initiated or caused by a primary
lesion or dysfunction in the nervous system
Peripheral neuropathic pain
Central neuropathic pain
Pain initiated or caused by a primary
lesion or dysfunction in the
peripheral nervous system
Pain initiated or caused by a primary
lesion or dysfunction in the
central nervous system
Pain Types: Nociceptive vs
Neuropathic
Nociceptive Pain
Arises from activation of nociceptors (pain receptors)
Proportional to degree of activation of afferent pain fibers
Acute, occasionally chronic
EXAMPLES: -
Postoperative pain
Mechanical low back pain
Sports/exercise injuries
Sickle cell crisis
1) Somatic Pain
- Well localized
- Aching, gnawing, sharp,
deep aching
throbbing, pressure-like
2) Visceral Pain
- Poorly localized, few nociceptors
- Crampy, colicky, throbbing, pressure-like,
- Autonomic: diaphoresis, hypertension,
Neuropathic Pain Prevalence
Ranges From 6.0-7.7%
10
9
% of patients
8
7.7%
7.5%
7
6.4%
6
6.0%
5
4
3
2
1
0
UK
France
Germany
Spain
Patients with axial back pain with a neuropathic component included in the survey
Neuropathic Pain Patient Flow Survey
CRPS
Neuropathic Pain
Mixed Pain
Nociceptive Pain
Pain initiated or caused by a
primary lesion or dysfunction
in the nervous system
(either peripheral or
central nervous system)1
Pain with
neuropathic and
nociceptive
components
Pain caused by injury to
body tissues
(musculoskeletal,
cutaneous or visceral)2
Examples
Peripheral
• Postherpetic neuralgia
• Trigeminal neuralgia
• Diabetic peripheral neuropathy
• Postsurgical neuropathy
• Posttraumatic neuropathy
Central
• Poststroke pain
Common descriptors2
• Burning
• Tingling
• Hypersensitivity to touch or cold
Examples
• Low back pain with
radiculopathy
• Cervical
radiculopathy
• Cancer pain
• Carpal tunnel
syndrome
Examples
•
•
•
•
Pain due to inflammation
Limb pain after a fracture
Joint pain in osteoarthritis
Postoperative visceral pain
Common descriptors2
• Aching
• Sharp
• Throbbing
Signs and Symptoms of Neuropathic
Pain
Sign/Symptom
Description (example)
Spontaneous
symptoms
• Spontaneous pain
Persistent burning, intermittent shock-like or
lancinating pain
• Dysesthesias
Abnormal unpleasant sensations
e.g. shooting, lancinating, burning
• Parasthesias
Abnormal, not unpleasant sensations e.g.
tingling
Stimulus-evoked
symptoms
• Allodynia
Painful response to a non-painful stimulus
e.g. warmth, pressure, stroking
• Hyperalgesia
Heightened response to painful stimulus e.g.
pinprick, cold, heat
Delayed, explosive response to any painful
Development of
Neuropathic Pain
10
Pain
Sensation
Hyperalgesia
Shift to
left with
tissue
injury
Normal
Pain
Curve
Allodynia
0
Stimulus Intensity
Innocuous
Noxious
M. Downing
‫"מדידת כאב"‬
Pain Treatment
Non-Opioids
+Adjuvants
WeakOpioids
+ NonOpioids
+Adjuvants
StrongOpioids
+ Non-Opioids
+Adjuvants
Severe
Moderate
Mild
Pain Intensity
The WHO Analgesic Ladder
1. Mackin G.A. J Hand Ther. 1997;10:96-109. 2. Gobal H. et al,Clin Drug Invest 1995;10:208-214. 3. Harati Y. et al, Neurology 1998;50:1842-1846
Emotion
Perception
Modulation
Transmission
Transduction
Pain behavior
suffering
pain
nociception
A multifaceted model for the
components of pain
”Prevalence of chronic pain
after surgery”
Prevalence of chronic pain following
surgery
Perkins &Kehlet
Macrae
Anesthesiology
Brit JAnaes
Breast
11-49%
23-49%
Thoracotomy
22-67%
5-67%
Type of surgery
Cholecystectomy 3-56%
3-27%
Inguinal hernia
15-63%
Vasectomy
0-37%
0-37%
Risk factors for chronic pain after
surgery or trauma
Severe acute pain after surgery or trauma
Pain before surgery
Immobilization after trauma or surgery
Re-operation
Radiation and cytotoxic drugs
Genetics!
How do we build an algorithm
NNT (Number needed to treat)
EBM
Safety Profile NNH (Number needed to
harm)
Side effect
Price
Registration
Treatment of Chronic Neurophatic
Pain
1) Pharmacologic
2) Physical and occupational therapy
3) Alternative approaches
5) Cognitive behavioral strategies, relaxation
techniques
6) Interventional procedures
Multi Disciplinary Integrative
approach
Barriers to Optimal Pain Management
Factors related to health care professionals
–
–
–
–
–
–
inadequate knowledge of analgesic pharmacology and pain therapy
poor pain assessment
concern about regulatory oversight
fear of patient addiction
concern about the side effects of analgesics
concern about development of tolerance to analgesics
Factors related to patients
– reluctance to report pain
– reluctance to take pain medications
Factors related to the health care system
– low priority given to pain management
– inadequate or inappropriate provisions for reimbursement
– restrictive regulation of therapeutic agents that are controlled substances
‫הולכת הכאב‬
Dysregulation of 5-HT and NE
in the brain are strongly
Pain
associated with depression.
Signal
The brain may perceive an
amplified
NE pain signal due to the
imbalance of 5-HT 5-HT
and NE in
the spinal cord.
This may explain why physical
symptoms are often the chief
complaint in depressed
patients presented in primary
care settings.
5-HT
NE
Pain
Signal
Epidurals for Post –Op Analgesia .
‫הזרקה אפידורלית‬
Brachial Nerve Block –Axillary
approach
SCS Technique
Patient controlled analgesia
PCA
120
100
80
intramuscular
PCA
60
40
20
0
0
1
2
3
4
5
6
7
8
Special issues
Postoperative Pain Management in:
Chronic Pain Patients
Patients on Chronic Opioid Treatment