Neuropathic Pain Dr. Christopher A. Jenner MB BS, FRCA Consultant in Pain Medicine, Imperial Healthcare NHS Trust Medical Director London Pain Consultants and Spinal Healthcare 5 th November 2009 VXXXX Date of preparation October 2009
Nov 03, 2014
Neuropathic Pain
Dr. Christopher A. Jenner MB BS, FRCA
Consultant in Pain Medicine, Imperial Healthcare NHS Trust
Medical Director London Pain Consultants and Spinal Healthcare
5th November 2009VXXXX
Date of preparation October 2009
Agenda
• Definition• Neuropathic v. nociceptive • Physiology• Epidemiology• Diagnosis• Management options
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Definitions (1)
• Pain. ‘An unpleasant sensory and emotional experience which we primarily associate with tissue damage or describe in terms of tissue damage, or both.’ (IASP 2001)
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Definitions (2)
• Time-course:
• acute
• chronic
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Definitions (3)
• Type:
• nociceptive
• neuropathic
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Nociceptive Pain
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Neuropathic Pain
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Pain Physiology
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Neuropathic Pain
Aetiology of NP
I
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Aetiology of NP
Infection
Neoplasia
Vascular
Iatrogenic
Trauma
Endocrine
Drugs
Autoimmune
Metabolic
Psychiatric
Congenital
Peripheral
Chemotherapy-induced neuropathyComplex regional pain syndromeHIV sensory neuropathyNeuropathy secondary to tumour infiltrationPainful diabetic neuropathyPhantom limb painPostherpetic neuralgiaPostmastectomy painTrigeminal neuralgia
Central
Central post-stroke painMultiple sclerosis painParkinson disease painSpinal cord injury pain
Dworkin R.H. A overview of Neuropathic pain: Syndromes, Symptoms, Signs and several Mechanisms
Clin J Pain (2002) 18:343-349
Neuropathic pain syndromes
Epidemiology of Neuropathic Pain
The Neuropathy Trust
Epidemiology of Neuropathic Pain
Prevalence of 2-4% in UK Over 30% neuropathy prevalence in
diabetesPredicted by 2010 ~ 1 million diabetes
sufferers with neuropathyUp to 70% neuropathy patients
experience pain
The Neuropathy Trust
Neuropathic Pain in Primary Care
Common after surgery? 1 in 6 experience post mastectomy phantom pain 1 in 7 experience post-thoracotomy neuralgia 1 in 8 experience severe post herniorraphy pain 1 in 33 experience phantom tooth pain after extraction
Macrae WA. Chronic pain after surgery BJA 87 (2001) 88-98
How Common is Neuropathic Pain in Primary Care?
Epidemiology of conditions (per 100,000 person yrs)
Post Herpetic Neuralgia = 40 ↓
Trigeminal Neuralgia = 27
Phantom Limb Pain = 1 ↓
Painful Diabetic Neuropathy = 15 ↑
Hall G. et al. Epidemiology and treatment of neuropathic pain: The UK primary care perspective.
Pain 2006; 122: 156–162
Clinical features of Neuropathic Pain
History
• Pain description- – burning/ shooting/ stabbing/ electric shock/
lancinating/ severe/ constant…..
• Local hypersensitivity- – allodynia/ hyperalgesia/ dysaesthesia
• Dysfunction
Examination
Check for: Allodynia (mechanical, thermal &
punctate)
Skin changes (autonomic activity)
Sensory disturbances Cold
Pin
Vibration
Soft touch
Diagnostic & Screening Tools
All based on use of pain descriptors and simple examination
LANSS scale Bennett, 2001 Neurop. Pain Questionnaire Krause, 2003 DN4 Bouhassira, 2005 ID Pain Portenoy, 2006 Pain Detect Freynhagen, 2006
Diagnostic & Screening Tools
LANSS Questionnaire
Items Common to all Screening Tools
Bennett et. al. Using screening tools to identify neuropathic painPain 127 (2007) 199–203
Pharmacological Treatment
• WHO analgesic ladder (abridged)
• + tramadol
• + opioids- buprenorphine TDD/ oxycontin/ fentanyl TDD
(New: sufentanyl TDD/ product X)
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Pharmacological treatment of Neuropathic Pain
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Neuropathic Pain Management
• Antidepressants – Amitryptilline
• Anticonvulsants- Gabapentin/ Pregabalin/ Carbamazepine/ Valproate
• Opioids• Local Anaesthetics/Analgesics
– Lidocaine/ EMLA
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• NMDA antagonists
• Sympatholytics
• GABA –ergics
• Capsaicinwww.londonpainconsultants.com
Future Agents for Neuropathic Pain
• Ziconotide (sea snail, conus magnus)
• P2X3- (purine) receptor antagonists (ATP) (knockout mice)
• Epibatidine (Equadorian poison dart frog)
• Morphine and ketamine
• Regular gabapentinwww.londonpainconsultants.com
Lidocaine plaster v. Pregabalin in PHNBaron et al., 2009: Study overview and design
* according to SmPC
Baron et al., (2009) CMRO. 25: 1663-1676.
NRS-3 response rate after 4 weeks, Per protocol (PP)
Baron et al., 2009: Results – PHN
Baron et al., (2009) CMRO. 25: 1663-1676.
Subject-based adverse event (AE) evaluation, Safety population
* p = 0.0020 * * p = 0.0001
Baron et al., 2009: Results – PHN
Baron et al., (2009) CMRO. 25: 1663-1676.
Physical and Alternative Treatments
Physical and Alternative Treatments
• Graded desensitisation
• Mirror box therapy
• Rehabilitation
Psychologically based therapy
Pain Management
• Psychological
CBT
Operant Conditioning
Psychoanalysis
Relaxation
Biofeedback
• Psychiatricwww.londonpainconsultants.com
Pain Management Programmes
Medication
• Goals (SMART- specific/ measured/ agreed/ realistic/ timed)
• Coping
• Contingency
• Pacing
• Education
• Pain Behaviours
• Reinforcement www.londonpainconsultants.com
Advanced Pain Management Techniques
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Nerve Stimulation
Nerve Stimulation (2)
Intrathecal Pumps
The Future?
• Demographics
• Healthcare advances
• ↑ Patient expectations and involvement
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Summary
• Incidence of NP increasing
• Nociceptive v neuropathic
• Management of NP in primary care
• When to refer
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Case reports/ Blogs/ Links/ Appointments
0845 045 0250
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Any Questions