Chronic pain again l.jpg
Sponsored Links
This presentation is the property of its rightful owner.
1 / 78

Chronic Pain Again PowerPoint PPT Presentation


  • 54 Views
  • Uploaded on
  • Presentation posted in: General

Chronic Pain Again. Dr. MC Chu Anaesthesia and Intensive Care PWH. Agenda. Remember the cases last time? Bear in mind the complexity of chronic pain Let’s try to treat them. Treatment principles. Pain as a symptom Find the cause and fix it Pathology oriented Works well in acute pain

Download Presentation

Chronic Pain Again

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Chronic Pain Again

Dr. MC Chu

Anaesthesia and Intensive Care

PWH


Agenda

  • Remember the cases last time?

  • Bear in mind the complexity of chronic pain

  • Let’s try to treat them


Treatment principles

  • Pain as a symptom

  • Find the cause and fix it

  • Pathology oriented

  • Works well in acute pain

  • Well accepted by patient and doctor


Treatment principles

  • Pain as a symptom

  • Find the cause and fix it

  • Works well here


Treatment principles

  • Pain as a symptom

  • Find the cause and fix it

  • Does all headaches have a pathology?


Treatment principles

  • Pain as a symptom

  • Control the symptom

  • Passive

  • Long term effects and side effects

  • Case specific

  • What are the options?


Symptom control

  • Medications

  • Antipyretics (paracetamol)

  • NSAID

  • Opioids

  • Antidepressants

  • Anticonvulsants

  • Steroids, muscle relaxants, etc.


Symptom control

  • Paracetamol

  • Effective in OA knees

  • Amadio Curr. Ther. Res. 1983

  • Effectiveness ~ Ibuprofen

  • Bradley N. Eng. J. Med. 1991

  • Safe and economical, NSAID sparing for elderly

  • Nikles Am. J. Ther. 2005


Symptom control

  • Paracetamol

  • Evidence in OA only

  • Hepatic and renal toxicity do occur

  • Medication induced headache


Symptom control

  • Medications

  • Antipyretics (paracetamol)

  • NSAID

  • Opioids

  • Antidepressants

  • Membrane stabilisers (anticonvulsants)

  • Steroids, muscle relaxants, etc.


Symptom control

  • NSAID

  • Best evidence from rheumatoid arthritis

  • Also good for cancer pain

  • Effective in 5 out of 10 placebo-trials for LBP

  • Effective in 4 out of 9 Panadol-trials for LBP

  • Doubtful value for non-specific musculoskeletal pain

  • Koes Ann. Rheum. Dis. 1997

  • Eisenberg J. Clin. Onco. 1994


Symptom control

  • NSAID

  • Annual GI bleed risk: 0.8-18% / year

  • Annual death rate: 0.03-0.1% / year

  • MacDonald BMJ 1997


Symptom control

  • NSAID

  • Risk increase with age, > 4 week use,

  • history of GI bleed / ulcer / CVS disease

  • Least damaging: Ibuprofen

  • Only effective prophylaxis: PPI

  • Yeomans N. Eng. J. Med. 1998


Symptom control

  • COX-2 specific NSAID

  • You know what happened to your patients


Symptom control

  • COX-2 specific NSAID

  • You know what happened to your shares?


Symptom control

  • Medications

  • Antipyretics (paracetamol)

  • NSAID

  • Opioids

  • Antidepressants

  • Membrane stabilisers (anticonvulsants)

  • Steroids, muscle relaxants, etc.


Symptom control

  • Opioids

  • Gold standard for cancer pain management

  • (mostly) cheap and readily available

  • Administered at every route


Symptom control

  • Opioids

  • Controversial for non-cancer pain

  • Limited (but positive) evidence of efficacy

  • Extensive side effects

  • Tolerance

  • Dependence

  • Divergence


Symptom control

  • Opioids

  • Controversial for non-cancer pain

  • “Physicians should make every effort to control indiscriminate prescribing, even under pressure from patients…”

  • Ballantyne N. Eng. J. Med. 2003


Symptom control

  • Opioids

  • Controversial for non-cancer pain

  • “Opioids are our most powerful analgesics, but politics, prejudice, and our continuing ignorance still impede optimum prescribing”

  • McQuay Lancet 1999


Symptom control

  • Opioids

  • Practical guidelines for non-cancer pain

  • Exhaust other methods

  • Aim at functional improvement

  • Limit prescription authority, monitor behavior

  • Slow release, avoid injectables

  • Opioid contract


Symptom control

  • Medications

  • Antipyretics (paracetamol)

  • NSAID

  • Opioids

  • Antidepressants

  • Membrane stabilisers (anticonvulsants)

  • Steroids, muscle relaxants, etc.


Symptom control

  • Antidepressants

  • Analgesic at below mood altering doses

  • NNT for diabetic neuropathy ~ 3.4

  • Collins J. Pain & Sym. Manag. 2000


Symptom control

  • Antidepressants

  • Analgesic at below mood altering doses

  • NNT for post-herpetic neuralgia ~ 2.1

  • Collins J. Pain & Sym. Manag. 2000


Symptom control

  • Antidepressants

  • How good is NNT of 2.1 to 3.4?

  • It is not good for this


Symptom control

  • Antidepressants

  • How good is NNT of 2.1 to 3.4?

  • It is really good for pain


Symptom control

  • Antidepressants

  • Major problem: side effects

  • NNH (minor) ~ 2.7

  • No consensus which one is best

  • Classically TCA

  • SSRI: seemed more specific on mood


Symptom control

  • Medications

  • Antipyretics (paracetamol)

  • NSAID

  • Opioids

  • Antidepressants

  • Membrane stabilisers (anticonvulsants)

  • Steroids, muscle relaxants, etc.


Symptom control

  • Anticonvulsants

  • Carbamazepime for trigeminal neuralgia

  • NNT ~ 2.6

  • NNH ~ 3.4


Symptom control

  • Anticonvulsants

  • NNT for diabetic neuropathy (red) ~ 2.7

  • NNT for post-herpetic neuralgia (white) ~ 3.2

  • Collins J. Pain & Sym. Manag. 2000


Symptom control

  • Anticonvulsants

  • Gabapentin

  • Less organ damage

  • No drug interaction


  • Want to have a break?


Symptom control

  • Intervention

  • Nerve / joint block

  • Counter-stimulation


Symptom control

  • Nerve block

  • Where to cut

  • How to cut

  • What is left behind


Symptom control

  • Nerve block

  • Where to cut

  • How to cut

  • What is left behind


Symptom control

  • Nerve block

  • Where to cut

  • How to cut

  • What is left behind


Symptom control

  • Nerve block

  • Where to cut

  • How to cut

  • What is left behind


Symptom control

  • CNS nerve block

  • Physically protected, relatively immobile

  • Synapses are chemically vulnerable

  • Effects (and side effects) are wide spread


Symptom control

  • Peripheral nerve block

  • Thick bundles of conducting cables

  • Mobile, difficulties with catheters

  • Impairment is profound yet localised


Symptom control

  • Visceral nerve block

  • Contain visceral pain fibres k

  • Usually deep seated

  • Anatomically diffuse l

  • Visceral functions .


Symptom control

  • Nerve block in chronic non-cancer pain

  • Preferably purely sensory block

  • Chemical / thermal neurolysis

  • Minimal dysfunction


Symptom control

  • Nerve block in chronic cancer pain

  • Cover most abdominal viscera

  • 90% good to excellent relief

  • Eisenberg et al A&A 1995


Symptom control

  • Joint block


Symptom control

  • Joint block


Symptom control

  • Transcutaneous Electrical Nerve Stimulation

  • (TENS)

  • Product of Gate theory

  • Better than placebo in short term

  • Minimal side effects

  • No long term benefit


Symptom control

  • Spinal cord stimulation

  • Patient controlled

  • No medication

  • Permanent (almost)


Symptom control

  • Spinal cord stimulation


Symptom control

  • Spinal cord stimulation

  • Failed back surgery

  • Isolated neuropathy

  • Ischemic heart disease

  • Peripheral vascular disease

  • Pain relief as a therapy


Symptom control

  • Spinal cord stimulation

  • de Jongste et al Br Heart J 1994


Symptom control

  • Spinal cord stimulation

  • How does it compare with the “golden standard”?


Symptom control

  • Angina attacks per week

  • PreopPost-opp-value

  • CABG (51)16.25.2<0.001

SCS (53)14.64.4<0.001

Mannheimer et al Circulation 1998


Symptom control

  • 6-months cardiac mortality and morbidity

  • MortalityMorbidityStroke

  • CABG (51)778

SCS (53)172

Mannheimer et al Circulation 1998


Symptom control

  • Spinal cord stimulation

  • Only suitable for smart patients

  • Technical expertise and follow up facilities

  • Complications do occur


Symptom control

  • Spinal cord stimulation

  • Cost: $ 80,000 HKD

  • Would you take it?


Treatment principles

  • Pain as a symptom

  • Find the cause and fix it

  • Symptomatic control

  • Pain as a disease

  • How is this disease like?


Pain as a disease

  • Pain

Insomnia

Depression

Socially deprived

Medical

Dependence

Think negative

In-activity


Pain as a disease

  • Our contribution

  • “Degenerative”

  • “Bone spurs”

  • “Nothing wrong”

  • “It is in your mind”


Pain as a disease

  • Our contribution

  • Misunderstanding on Waddell’s signs esp. malingering

  • Incorrect attempts to test for placebo e.g. saline test


Pain as a disease

  • Need a multi-disciplinary approach

  • Clinical psychology

  • Physiotherapy

  • Occupational therapy

  • Nursing

  • Social work / vocational training


Pain as a disease

  • Need a multi-disciplinary approach


Pain as a disease

  • Alleviate their depression

  • Motivate them to mobilise despite pain

  • Encourage active coping

  • Reduce dependency on medical input

  • Stop searching for a cause

  • Stop giving analgesics together with side effects

  • Cognitive behavioral therapy


Pain as a disease

  • Cognitive behavioral therapy

  • Pain intensity (VAS)


Pain as a disease

  • Cognitive behavioral therapy

  • Depression (HADS)


Pain as a disease

  • Cognitive behavioral therapy

  • Catastrophising (PCS)


Pain as a disease

  • Cognitive behavioral therapy

  • 40 meter carrying load (pounds)


Pain as a disease

  • Cognitive behavioral therapy

  • Analgesic consumption (types)


Pain as a disease

  • Cognitive behavioral therapy

  • Pain is the same, but

  • More active

  • Less depressed

  • Less doped


  • Before we move on to the last bit


Pain as a specialty

  • Anaesthesia and pain

  • Expertise in peri-operative pain relief

  • Analgesics

  • Regional nerve blocks


Pain as a specialty

  • Anaesthesia and pain

  • Dr. John J. Bonica

  • “Father of pain medicine”


Pain as a specialty

  • Getting established

  • IASP and its 65 global chapters

  • Over 300000 members of multiple specialties


Pain as a specialty

  • Anaesthesiology

  • Orthopediac surgery

  • Neurosurgery

  • Oncology / palliative care

  • Neurology

  • Rheumatology

  • Rehabilitative medicine

  • Psychiatry

  • Radiology


Pain as a specialty

  • … is to specialize in everthing!


Pain as a specialty

  • Opportunity to work with other doctors


Pain as a specialty

  • Other activities


Pain as a specialty

  • Training

  • Diploma in Pain Management (HKCA)

  • Fellowship in Pain Medicine (ANZCA)


Pain as a specialty

  • Pain centres at HK (2006)

  • AHNHPWH

  • QEHUCH

  • QMHPYNEH

  • Smaller scale ones at DK, PM, etc.


Resources for you

  • Internation Association for the Study of Pain

  • www.iasp-pain.org

  • HK College of Anaesthesiologists

  • www.hkca.edu.hk

  • Oxford pain Internet site

  • www.jr2.ox.ac.uk/bandolier/booth/painpag/index.html


  • Login