Transcript The Role of the Chronic Pain Physician in Palliative care

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Anesthesia and Chronic pain management,
Cape Breton Regional Hospital
I have no disclosures and do not receive any
sponsorships from any of the companies that
might be mentioned
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Background – evolution
in cancer care – earlier
diagnosis, more
effective treatment with
increased survival.
WHO ladder approachlimitations in certain
circumstances.
Multidisciplinary/multi
modal approach –
decision making.
The role of the
‘interventional
procedure’.
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Assessment is the key
? Tumor related
? Therapy side effects
? Chronic pain in cancer patients
Psychosocial assessment
Physical exam
Directed studies
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Realistic expectations
Rarely eliminate “all pain”
Spectrum of ‘success’:
Improve QOL
Reduce medication including side effects
Avoid complications
Obtain thoughtful, realistic informed consent
(including family)
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Radiation: Conventional/Stereotactic
Biphosphonates: MOA-supresses osteoclast mediated
bone resorption, eg IV zoledronic acid
Radiopharmaceuticals: samarium, strontium
Danosumab: (RANKL-Ab) – osteoclast maturation
inhibitor
Hormonal therapies: prostate/breast
Orthopedic treatments: Bracing/Surgery/PMMA
injection
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60-80% well addressed by oncologists
Poorly controlled group – who to call?
Depends on the problem
Depends on local expertise/availability
Depends on patient preferences
But call someone!!
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Traditional/Etiologic: Nociceptive vs. Neuropathic
New Challenge: ‘Acute’ vs. ‘Chronic Cancer Pain’
Pain Throughout the cancer cycle:
Pain at diagnosis
Painful diagnostic procedures and/or resective
surgery
Pain due to chemo/radiation
Painful progression/metastasis
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WHO 30 years on – time for critical reappraisal
? Treatments available in 1982
Lack or efficacy
Not evidence based
Long-term opioid efficacy and side effects problematic
Mechanism based, individualized approaches
important
Last resort WHO options offer better pain
control/fewer side effects
Pain problematic throughout cancer cycle – prevent
chronic pain by addressing acute pain better
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Treat pain early to prevent morbidity
Use adjuvants/procedures/physical medicine
techniques early to avoid morbidity and
transition to chronic pain
Adopt chronic pain treatment strategies early
in the cycle
‘Consider’ intervention the fourth step in the
WHO ladder approach
No rules exist for the timing of interventional
procedures – it is your call
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“Incidental” Nature
Peaks/Valleys hard to capture
Bracing challenging
Surgical options may be limited r/t
overall debility
“Snowball effect” of debility to morbidity
to mortality
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Multidisciplinary care
Primary care, pain specialist, physical medicine,
surgeon, psychologist, palliative care physician,
physical therapist, occupational therapist, social work,
chaplin
Multimodal Care
Adjuvant medications
Procedures/injections/RF/implantables, etc.
Opioids
Topicals
Holistic approaches
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When:
Refractory to usual management
Unacceptable side effects from analgesics e.g.
opiate induced hyperalgesia and myoclonus
Which:
Neuraxial infusions
Other pain procedures: Nerve blocks,
neurolytics, radiofrequency, vertebral
augmentation, etc …
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Neuraxial Treatment indicated in:
Intolerable side effects of existing
oral/intravenous management
Inadequate analgesia on oral intravenous
management
Options:
Tunneled/temporary epidural or plexus
infusions
Refractory Cancer Pain
Life expectancy ≤ 3 months
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Need for local anesthetics (e.g. chest wall mass) anticipated
Need for high dose LA
Epidural catheter (tunneled e.g. Du Pens)
Diffuse pain, epidural space obliterated, need for IT PCA/
unavailability of programmable pump
Intrathecal catheter (tunneled e.g. Du Pens)
Life expectancy ≥ 3 months
Somatic / visceral pain
Single Shot IT trial
Neuropathic Pain
Equivocal results
IT Catheter Trial
≥ 50% pain relief
Implant pump
≤ 50% pain relief
Further medical management
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Retrospective review (baseline vs. 3 months)
60 months, N=160
138 available at 3 months
Numerical pain scores reduced:
7.09 ± 1.8 to 3.7 ± 2.4 (p<0.001)
Oral opioid intake declined
577 mg/d to 206 mg/d MOED (p<0.001)
Drowsiness/mental clouding decreased:
- 5.4 to 2.9/10 and 4.5 to 2.5/10
Zhuang M et al, IARS 80th Congress March 2006, San Francisco, CA
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N = 300
Serious infections approx 10; 5 pump explants
(< 2%)
Paralysis 1 (<< 1%)
Revision rate/catheter, etc: 5 – 10%
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Meta-Analysis
Superficial infection 2.3%
Deep infection 1.4%
Every 71st patient will have an infection after 54 days of
therapy
Bleeding 0.9%
Neurological injury 0.4%
Aprili D et al, Anesthesiology 2009
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Likely to help
Focal pain
No contraindications
Neurolytic blocks (alcohol, phenol or glycerol)
where motor/sensory separation exists. Consider local
block first
RF ablation (nerves/tumor)? Role of pulsed RF
Vertebral augmentation
Plexus blocks
Simple injections
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Cancer patients can have coexisting VCF’s
Trend is towards ignoring these fractures
This is possibly benign neglect
Quick and relatively affordable procedure with
excellent results and pain relief
NEJM article condemning vertebroplasty had poor
design and statistics. It compared vertebroplasty to
poorly (non-ISIS standard) performed medial
branch blocks
Role of vertebroplasty vs. kyphoplasty vs. the
significant discrepancy in procedural cost vs.
benefit
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Indicated for intractable pain after failure of
less invasive procedures in patients with a
short life expectancy
May provide profound pain relief for pelvic
malignancies at the cost of bladder and bowel
control
Never the first treatment of choice
Experience very limited in the current
environment
A valuable tool however, should not be
discounted
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Severe intractable pain
Intolerable side effects of analgesic therapy
Intrathecal catheter not an option
Advanced/terminal malignancy
Pain well localized – unilateral, localized trunk or
involving only a few dermatomes
Primary somatic pain mechanism
Absence of intraspinal tumor spread
Pain relieved with prognostic local block
Realistic expectations by patient and family
Patient clearly understands possible side effects
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Quality of analgesia might be less than after
local anesthetic
Duration of effect not permanent
Requires downward titration of opiates
Lack of procedural skill in physician pool
Potential for long term complications
Neuropathic pain and dysesthesias
Analgesic failure – incomplete block, wrong
neural target
New pain at distal site
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Celiac plexus block – relieves pain from intra
abdominal viscera excluding left colon and
pelvic content
Superior hypogastric plexus block – manages
visceral component of pelvic pain
Ganglion Impar block – manages persistant
burning associated with pelvic pain
Intercostal blocks – manages chest wall
malignancy
Gasserian block – manages trigeminal tumor
infiltration pain
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Meticulous selection significantly increases
success
Inferior to intrathecal pumps, cost of the latter
often prohibitive – visible versus invisible cost
Both alcohol and phenol are cheap
Possible future resurgence of these techniques
due to increasingly hostile financial
environment
Do not allow perfect to be the enemy of good