| |
November 2000
Volume 64 |
Number 11
|
| |
|
| Pain
Medicine in the Year 2020 |
Doris K. Cope, M.D.
Case 1
V.F., a 55-year-old woman comes to the
pain clinic with a diagnosis of osteoarthritis and degenerative
joint disease in her hips, knees, lumbosacral facets, ankles,
feet and cervical spine. She is 4'11" tall, weighs 384 pounds,
is depressed and has an eating disorder. She has been noncompliant
with her physical therapy and exercise program and now finds it
difficult to walk as far as her mailbox in the front yard. She
has tried unsuccessfully to lose weight on various regimens, including
the high-protein, low-fat goldfish diet, the ginger ale and bananas
diet, and the papaya juice diet. In fact, she has gained 33 pounds
on her last diet that consisted solely of falafel and lentils.
Her HMO is no longer paying for any surgical intervention until
the year 2028, should she find a surgeon to offer her a procedure
to relieve her chronic unremitting bone and joint pain that is
now a 15/10 in intensity. She arrives at the interdisciplinary
pain/behavioral medicine clinic a desperate woman.
Her physician whisks her next door to
the PET scanner where no one is surprised to find she has rampaging
activity in the ventromedial nucleus of her hypothalamus (VMH)
with an induced hyperphagia as well as decreased activity of her
descending antinociceptive pathways with resultant low levels
of serotonin and norepinephrine. Under a local anesthetic in the
sterile treatment suite next door, the pain medicine interdisciplinary
team implants electrodes in her thalamus and midbrain.
| The ability to map transmission
of pain and other disorders not only to block but to alter
and reprogram neurotransmission is now a very active and ever-changing
research area. |
She is then returned to the PET scanner
with high frequency stimulation applied to her dorsal columns
and thalamus and low frequency stimulation to her VMH, which normalizes
her radioactive uptake picture, improves her depressive symptoms
and decreases her desire for binge eating. She then is sent home
with a computer chip embedded in her designer computer earring
that can also be worn in the navel for evening wear. Whenever
she feels depressed or has the urge to binge, she just presses
the reset button. The high- and low-frequency stimulators communicate
with each other in appropriate reverberating feedback loops, fire
up, and she is once again restored to electro-physiological balance.
Case 2
Dr. O.C.D. is an amazing man. He began
life as an infant picking specks of lint off his crib bumper pads.
He was always a fastidious child who worried about germs he could
not see and eschewed "dirty" activities in the sandbox.
He was careful in his personal activities, checking his door and
window latches and plug-in appliances multiple times after leaving
his house. Of course he sailed through medical school, excelling
in microbiology and the more arcane biochemical pathways. Not
surprisingly, he became an anesthesiologist, where he specialized
in having the tidiest intravenous lines in the hospital, the most
immaculate anesthetic records, with all the checks lined up in
perfectly straight rows, and a spotless anesthesia machine. He
got into trouble, however, when he began raging at the operating
room personnel about the clutter in the hallways and throwing
boxes of orthopedic equipment at the surgical residents. When
he physically assaulted a misplaced C arm, the department chair
knew she needed to take action.
Dr. O.C.D. was sent to the interdisciplinary
pain/behavioral medicine clinic where his PET scan showed hyperactivity
in the fiber bundles of the anterior capsule. He had not only
abnormal firing rates, but also abnormal firing patterns that
fortunately were correctable with deep brain stimulation. He had
high and low limits set on his neuronal firing rate and pattern
grid placement to avoid further disturbing outbreaks in the future.
After reprogramming, he was returned to his duties, once again
a productive citizen and contributor to his anesthesiology department.
Case Discussion
Far-fetched? Indeed. Impossible? No. We
already have the technology to diagnose abnormal firing rates
and patterns and the ability to intervene. The state of spinal
cord stimulation (SCS) and deep brain stimulation (DBS) is now
rudimentary, similar to the radio jammers of World War II who
disrupted the airwaves with their interfering signals. But soon,
with sophisticated diagnostic and interactive feedback-generating
capabilities, modern medicine may be able to not only block pain
and other inappropriate signals, but operationally define healthy
signals and reprogram aberrant signal transduction.
In pain medicine, we are currently implanting
dorsal column stimulators at multiple sites in the spinal cord
to compete with pain signal transmission. Newer electrode arrays
with increasingly sophisticated communication between individual
electrodes and combinations of electrodes in an exponential number
of varying patterns are now a reality. SCS is being used today
to treat failed back surgery syndrome, peripheral neuropathy,
complex regional pain syndrome, ischemic heart disease, refractory
angina and even refractory interstitial cystitis, among other
conditions.
Research in diagnostic imaging of neuronal
activity is also endemic at many academic medical centers, including
positron emission tomography (PET), single photon emission computed
tomography (SPECT), functional magnetic resonance imaging (fMRI)
and near infrared spectroscopy techniques (NIRS). This new technology
is currently being utilized to detect changes in neuronal activity
induced by stimulating electrodes placed at specific sites in
the thalamus and cortex and more peripheral nerve tracts in a
group of techniques termed deep brain stimulation. The ability
to map transmission of pain and other disorders not only to block
but to alter and reprogram neurotransmission is now a very active
and ever-changing research area. The future uses that we in medicine
will make of these expanding capabilities can only barely be imagined.
The old truism in medicine "you can either lead the disease
or let the disease lead you" suddenly has new meaning.
| |
|
Doris
K. Cope, M.D., is Professor, Anesthesiology and Critical Care
Medicine, University of Pittsburgh Medical Center (UPMC),
and Clinical Director of UPMC Pain Medicine, Pittsburgh, Pennsylvania.
|
|
return to top
|