Monday, January 11, 2010

Dr. Teicheira, Chronic Pain, and New Theories

Dr. Teicheira's theory on fibromyalgia is that it's caused by untreated pain; essentially, the nerves are trained to interpret every signal, even neutral ones, as pain, because the majority of the signals they receive are pain.  Teicheira would like to draw and quarter any doctor who tells a patient "just tough it out" rather than prescribing pain pills; since it took me 7 years between first request and finally getting the RX (while hearing every ridiculous excuse in the book), I'll gladly hold them down while he does the "surgery".
 
Just heard about a woman with a chronic pain condition whose doctor has the theory that by putting her in a medically-induced coma, he can re-boot the system and re-train the nerves.
 
Which is when it dawned on me that I'm still working on my July refill of Vicodin.  Apparently we've achieved the same thing without the hospitalization: got the nerves used to not feeling pain so now they only signal pain when I've actually done something stupid (like lift a 50-lb box), which is why I was looking at the date on the pill bottle. 

Was referring to these notes from a lecture I went to a few years ago, and  thought it was worth a re-visit here, too.

- - - - -

DAVID TEICHEIRA, M.D.   Sacramento Pain Clinic

"Pain is not well understood"

The International Association for the Study of Pain defines pain as: "An 
unpleasant sensory and emotional experience associated with actual or
potential  tissue damage, or described in terms of such damage"

ACUTE pain is an alarm system    nociceptive pain

nerve impulses are translated by the limbic system   if you  didn't have a
limbic system, you wouldn't have emotions

PERSISTENT pain is a complex state of mind that is the result of many 
combinations

people with chronic pain have trouble sleeping   stimulation of 
thalmic/limbic system

if severe pain is allowed to persist for more than 24 hours, neuroplastic  changes associated with the development of intractable chronic pain syndromes  are evident --  damaged mechano-receptor nerve grows over the nociceptor  nerve after 24-48 hours; the nociceptor atrophies.  -- This may be  permanent  
no one knows.

Referred pain uses the same set of nerves

Prescriptions do not take pain away, they just make it easier to ignore 
your pain

You only feel your pain when you're paying attention to it   when  you are
thinking about your pain, that's your cue to do ANYTHING ELSE

as a result of intense pain, neurons in the spinal cord that help to  prevent pain transmissions actually die.  At the same time,  pain-transmitting neurons grow more connectors to other nerves, become more  sensitive, and react more strongly to a painful stimulus

CFS/FMS deal abnormally with pain as a memory.  On a PET scan, the  brain is all lit up all the time.  The process is abnormal, but the pain is  real.

Chronic back pain patients lose 5-11% of their cortex.

Your brain can't tell the difference between chronic pain and new  injury  
flares are not damage indicators

He recommends work through the pain, but don't fight through the pain

MEDICAL MANAGEMENT
opiates
muscle  relaxants
anti-neuropathic agents

Chronic pain is different   it's pathological

Neurontin wasn't a good seizure drug, but decreases rate of nerve firing,  no known long-term effects

morphine and other opiates are incredibly safe.

RX doesn't make the pain go away   there's a plateau where more  doesn't do
more   they're better than nothing

pseudo-addiction means you're undertreating   if patient asks for  more, it
usually means more works better

only two ways to entirely take away pain:
local  anesthetic
Saponin SP (for Substance P)   FDA approved only  for use on elderly
animals who'll die in a few days, because it kills all the  pain nerves   doing
this will cause more damage in the long run

distinct neurological pathways for acute vs. chronic pain

NNT   Number Needed to Treat   number of people who  need to take the drug
to get one to feel better
Neurontin's NNT is 3.4  = only 1/4 will get relief
Morphine's NNT is 8 = only 1 in 8 will get  relief
Ibuprofen's NNT is 5 = only 1/5 will get relief

WHY WE HAVE MEMORY PROBLEMS
both chronic pain and long term memory  require the NMDA pathway for
processing
mice with poor memory didn't  develop chronic pain if they were deficient
in NMDA
but with 2x NMDA,  they had a great memory and developed chronic pain easily

intense pain can result in permanent changes in the Central Nervous System 
resulting in phantom pain   this can take years to develop

chronic pain does go away for most people
chicken pox ends up in  your RNA => shingles => nerve damage

reticular activating system   pain and sleep are connected

HERBAL TREATMENTS SHOWN TO REDUCE MUSCULOSKELETAL PAIN
Devil's claw  extract   the most effective dosage for both osteoarthritis
and low  back pain is 50 mg of harpagophytum procumbens daily for at least
2-3  months
Bromelain   ananas comosus, pineapple   shown to  significantly decrease
Substance P release
Turmeric root   curcuma  longa   1125 to 2500 mg/day
Omega 3 fatty acids   salmon,  halibut, cod, herring, mackerel and tuna,
flax seeds, canola oil and  walnuts   1200 to 2400 mg daily

Research links pain sensitivity to gene   Johns Hopkins  neuroscientist
George R. Uhl, M.D., Ph.D.

ABNORMAL PAIN MEMORY HELPS TO EXPLAIN FIBROMYALGIA
The symptoms of  fibromyalgia may be the result of a central nervous system
that "remembers" pain  sensations for an abnormally long time, according to
research presented at the  American College of Rheumatology Annual
Scientific Meeting in  Philadelphia.  Fibromyalgia affects about 2% of the US
population.

Researchers at the University of Florida applied heat stimuli to the hands 
of healthy controls and fibro patients.  Fibro patients experienced 
CUMULATIVE pain, indicating abnormalities in spinal cord pain processing, and 
RESIDUAL pain when the stimuli were applied at intervals.  Researchers  found
that the residual pain experienced by fibromyalgia patients was widespread 
and not limited to a single area of the body.

"Because the effect of the first experimental stimulus does not rapidly 
decay in fibromyalgia patients, the effect of subsequent stimuli adds to the 
first, and so on, resulting in ever increasing pain sensations," said lead 
investigator Roland Staud, M.D.  "Our findings provide evidence for 
abnormal central nervous system mechanism of pain in fibromyalgia patients and 
have significant implications for future therapies, which need to target these 
abnormal central pain mechanisms."

1 comment:

Joanne said...

My 6 1/2 years of chronic pain arthritis and muscle weakness diagnosed as Fibromyalgia/ ME/CFS was eventually diagnosed as Lyme Disease. Simple antibiotic Amoxycillin improved my health and after many months I no longer have pain and have my health back. So in my case it was a bacterial infection causing all my symptoms.
Sadly with the controversy over diagnosis and treatment of Lyme Disease see http://www.ilads.org/ there will be many thousands of patients who are not properly assessed for Lyme disease.