Phantom Limb Pain

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Amputation & Phantom Pain
Thom Bloomquist
MSN, CRNA, CH, FAAPM
Advanced Anesthesia
& Pain Management
Bow, NH
Mass. knows about amputees
Learning Objectives

To explore and discuss;

the incidence and causes

the pathophysiology

neuroplasticity in phantom pain and other
acute-to-chronic pain states

strategies for management with a multimodal
and multidisciplinary approach

the possibility of phantom pain prevention
Amputation

New amputee each year –
185,000

Estimated total US
amputees (limb) –
2, 000,000.

Lower extremity
amputation,
(diabetes) - 55% will
require amputation of
other leg within 2‐3 years
Amputation health care
costs per year $8.3 billion
(U.S. only)
Incidence of Phantom Pain
 70%
- burning, cramping
other qualities of
phantom pain

first few weeks post-op
 50%


suffer
7yrs after
some life-long continuous
or intermittent
 Burning
 Stabbing
 Crushing
 Twisting
 Lightning-like
 Mal-positioned
part
Phantom pain

Also reported after
amputation of
intestines, breasts,
teeth and genitals.

What is special about
cuts nerves and
amputation?

NOTHING!
Wow! I didn’t
know that!
Causes
 Vascular
disease (54%) including diabetes
and peripheral arterial disease,

amputations caused by diabetes
increased 24% from 1988 to 2009.
 Trauma
(45%),
 Cancer (less than 2%)
 Congenital malformation (small %)
Under-treated Amputation Pain
 Can
lead to chronic pain
 Also
common after thoracotomy +

mastectomy, herniorrhaphy….
~20-40%
of ALL surgeries
Elements of Chronic
Phantom Pain
 Somatic
pain
 Psychogenic
 Myofacial
Pain
 Neuropathic

aspects
pain
Sympathetically Maintained Pain (SMP)
Psychogenic Factors

Of course! But not
psychosomatic - there
is true anatomic basis
for this pain

The illogic of pain in a
part that is no longer
there - “Am I nuts?”

Life long phantom
limb pain?
Somatic Pain
 Remaining
primary pathology (vascular
disease, tissue damage from trauma)
 Additional
stress on affected & nonaffected joints/tissues due to altered
biomechanics.
 Overuse
syndrome of remaining structures
and tissues
Neuropathic pain
 Post
amputation neuroma - can take
weeks to form but spontaneous ectopic
discharge begins at moment of nerve
division and in some nerves never fades.
 “…self
sustaining neuronal activity at the
spinal cord level….if exceeds a critical
level pain may occur in the phantom limb”
(Raj)
Sympathetically Maintained
Pain (SMP)
 Neuroma
firing is increased by
sympathetic activity (Nor-Epi)
 Example:
urination, defecation and
ejaculation can activate sympathetic
efferents and trigger episodes of phantom
arm pain.
“Wind-Up”
 Once
the noiceptive system is stimulated,
suppression of pain signaling becomes
more difficult and leads to …


Hyperalgesia (severe pain from mildly noxious
stimuli)
Allodynia (pain produced by innocuous
stimuli)
Sherman, R.A. , Phantom Pain, 1997, New York: Plenum Publishing.
Transmission in Spinal Cord
Neuroplasticity of Entire
Nocoiceptive System?

Peripheral,.e.g., neuroma

Spinal cord level
(sensitization and perhaps
hardwired WDRs)

Cortical-reorganization
alteration of neuromatrix
Neuroplasticity
 Critical
adaptability us evolve when
dinosaurs died out (a trait we may need in
the future?) can work against us in this
situation.
 However,
that very stimulus-response
relationship gives us a clue.

Cause  Effect
Cause of Phantom Limb Pain
 Not
clearly established
 Combination
of peripheral, central and
sympathetic factors
 Positive
correlation between painful limb
pre-op and developing phantom limb pain
 Recruitment
of normally silent highthreshold nociceptors
 Genetics
 Chemically
induced?
How to Treat Changed Anatomy?
 Best
Rx may be prevention!
 Nociception
drives the changes.
Effective pain management may
decouple the stimulus-response
relationship.
stimulus – prevent the
response!
 Diminish
Evidence? Yes!
 “Pre-op
epidural……. (Bach).
 “Perioperative
epidural with diamorphine,
clonidine and bupivacaine….. (Jahangiri).
 “Pre-,
intra- and postoperative
epidural…(Gehling)
In other words …
 Preliminary
evidence - effective
pre-operative analgesia
IN COMBINATION WITH
effective sustained post-operative pain
management
……can lower the incidence +/or severity of
phantom limb pain.
How?
 “Because
of the
low success rate of
treatment in
chronic phantom
limb pain, …
prevention cannot
be
overemphasized”
(Raj).
Multi-Modal and Multidisciplinary
Pain Management
• Pharmacological
• Non pharmacological
• Psychchological / social
Primum non nocere!
 Acute
pain strategies can be
counterproductive in chronic pain
 Higher
amputation attempted –
------ restarted same process!
Neuropathic Pain - Rx
 NSAIDs
are ineffective and opiates are not
first line for neuropathic pain
 Local
anesthetics (Na+ Channel blockers)
can provide pain relief in doses that will
not cause sensory or motor block
MMPM - Medications for
Chronic Pain
 Antidepressants
(Tricyclics, SNERIs,
SSRIs, Dopamenerics)
 Alpha
2 agonists (clondine)
 Antiarrhythmics
(mexiletine, lido)
 NSAIDs
(Cox 1 or Cox 2)
 Opiates
- when appropriate
Anticonvulsants



Carbamazepine
Gabapentin
Lamotrigine

Pregabalin
 P.O. Pre-op -D.O.S.

Topiramate
Valproic Acid and
Derivatives ***

Narcotics for Chronic Pain
(selected cases)
 Oxycontin
and MSContin - work well
(expensive)
 Methadone
(just as effective and less
expensive)
 Provide
immediate release preparation for
breakthrough pain
 Use
MMPM to lower narcotic requirement
and increase effectiveness
PERCOCET
VICONDIN
EUPHORIA
METHADONE
OXYCONTIN
MS CONTIN
WITHDRAWAL
PAIN
LEVEL
Topical - Pharmacolgic
(peripheral factors)

Mutli-cmpd topical preparations


E.g. gabapentin, NSAID, local anesthetic
combination from compounding pharmacist.
5% lidocaine patches (Lidoderm)
 OTCs
(capsaicin, ASA)
NMDA Blockers
 Receptor
site modulates nociceptive
afferent signals.

resting state, blocked by Mg+.
 Ketamine
 Also


amantadine (antiviral),
dextromethorphan (cough medicine).
Perioperative Epidurals
 Effective
but may not feasible in your
setting
 Expensive
 Invasive
 Complication
rate
Option? – O. P. MMPM

Consider mutli-modal program including:






NSAID (Cox1 or Cox2)
Opiates (SR & IR)
Antidepressants (multi-pathway)
Anticonvulsant
NMDA blocker (dextromethorphan)
Clonidine ?
Outpatient Program - cont’d
 Important
- include counseling with
prepared amputee & psych.
 Meet with Prosthetist
 Include family/spouse
 Amputee support group
(no “Whine fests)
 ACA Peer Visitor
Non-Pharmacologic Modalities

Acupuncture

Heat

Biofeedback

Massage

Chiropractic

Meditation

Cold

Psychotherapy

Electrical Stimulation

Shrinker Socks

Exercise

Wearing Your Artificial
Limb
Hypnosis (huge!)

When desired, the
mind can literally
affect what the body
does/perceives.
 Proof?
 Visualize a lemon
 Smell the lemon – cut
the lemon- feel the
juice – bite the lemon
– taste the lemon
Did you salivate?
(I did)
It’s that
simple and
this was the
merest
example
Mirror Therapy
The subconscious mind can
re-map perception
Multi-disciplinary PM Team
 Anesthesia/Pain
Mgt.
 Primary
 PT/OT/Massage
 Prosthetist
 Psych
(ARNP, PhD, MD/DO)
 Support group

Survivors or “whine festival”
Progress - but more to do
What’s in he pipeline?
Osseointegrated pins

Neuroplasticity as a
treatment?
 You
can play an important role in
preventing unwanted neuroplastic
changes!
 You can be somebody’s hero!
Thank You!
My family sleeps well & safe – because of them
History
The Rig-Veda, an ancient sacred poem of
India, is said to be the first written record
of a prosthesis.
Written in Sanskrit between 3500 and
1800 B.C., it recounts the story of a
warrior Queen Vishpla, who lost her leg in
battle, was fitted with an iron prosthesis,
and returned to battle.
History
 Herodotus
wrote of a prisoner who
escapes his chains by cutting off his own
foot. He later fashioned a substitute from
wood.
 The
oldest known artificial limb, dating
from 300 BC was made from copper and
wood - unearthed near Capri, Italy.
In France
 Parre,
a French surgeon describes
Phantom limb pain in 1551.
 Larry,
Napoleon's surgeon, recorded in his
memoirs that extremely cold weather
(-19 oF) allowed him to perform painless
amputations.
Revolutionary War
“If amputation was chosen, the patient was
laid out at table height, covered with
double blankets, and given pillows for his
head. Alcohol, if available, was used to
help sedate the patient. The following
procedure was then performed by a
surgeon.
A good surgeon cut fast, performing the
procedure in about a minute. If the patient
was lucky, he'd pass out before feeling the
searing pain.”
Civil War
 Chloroform
came into use for anesthesia,
for PM. Opium and derivatives were widely
used.
 Civil
War veterans
commonly suffered
in agony from war
wounds for the rest
of their lives
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