Microsoft word - persistent pain doc 2007.doc

Membrane Stabilisers - Medicines that ‘stabilise’ nerve cells and prevent them from
sending abnormal pain messages are proving to be very helpful in PPP. This type of
medicine was originally used in epilepsy and so belongs in the family of ‘anti-epileptics’.
Note that this is another example of a medicine being developed for one purpose,
and then as knowledge expands, finding that it can be used for another problem.
This is an important point to grasp because I find patients who, despite explanations to
the contrary, leave the consultation thinking the doctor is treating them for depression or
epilepsy when they came in with a pain problem!
Sodium Valproate (Epilim) The regime I usually follow is to start with a 200mg. tablet,
taken as a single dose with the evening meal. This is increased by 200mg. weekly until
six tablets are being taken. At this point blood levels are taken and used as a guideline
for adjusting the dosage. (The level in the blood depends on factors such as rates of
absorption, breakdown, and clearance by the body, and varies for different individuals).
When the appropriate level has been reached the medicine can be changed to a larger
dose tablet (500mg.), still taken as a single dose with the evening meal. This medicine
needs to be taken long term (probably greater than one year) to give the cells in the
spinal cord a chance to “calm down” and reduce the volume of pain messages being
sent to the brain.
Carbamazepine (Tegretol) has a similar action and is taken twice daily starting with
200mg controlled release tablets, half a tablet (100mg.) in the morning and half in the
evening, with food. Each week the dose is increased by 100mg. until adequate pain
control is achieved.
Gabapentin (Neurontin) often the medication of choice but needs applying for and this
can take up to 2 weeks to get.
Dose starts at 300 mg four times a day, and can be increased slowly up to 2 capsules
four times a day. The last dose at bedtime can be taken without food.
Mexiletine. This was developed as a medicine to stop irregular/fast heart rhythms, and
works to stabilise nerve cells carrying excessive “pain messages”.
Some patients respond well to quite low doses of this medicine, starting with 50 mg.
twice a day and building up by 50mg. each week. It is available in a slow release form
and some patients find that taking one of these capsules twice daily can modify their
pain messages considerably.
Other Medications - There are a range of specialised medicines that may have a part to
play in the management of PPP.
If they are appropriate for your type of pain problem, they will be discussed on an
individual basis.
APPENDIX:
Pain Killers - These include soluble aspirin (‘disprin’), paracetamol (‘panadol’), codeine/paracetamol Paradex), and nefopam (‘acupan’).
The problem with all these drugs is that they need to be taken regularly, eg every four
hours, so that a steady level is built up and maintained in the bloodstream, and in turn,
in the body’s tissues. This is particularly important for paracetamol, which is effective on
the cells in the spinal cord but needs to be taken four hourly for at least three days,
before good analgesic (pain blocking) effects are obtained.
Note that dextropropoxyphene can cause muscle pain (Paradex, Digesic)
Non-Steroidal Anti-inflammatory Drugs (NSAID’s) - These include Indocin, Brufen,
Voltaren, Naprosyn, Oruvail, Feldene, Tilcotil and Surgram. They have, as the name
suggests, an effect against inflammatory substances, thus reducing the pain associated
with inflammation. However, some also have a recently discovered role in blocking pain
message transmission in the spinal cord, this depends whether the medication can get
in the right region to work (lipid soluble or water soluble). The NSAID’s vary in their
‘pain blocking’ effects and I prefer Naprosyn, followed by Brufen as the ones of choice.
Approximately fifteen percent of people have problems with side-effects which cause
stomach and intestinal upsets. The tablets/capsules must be taken with food and
stopped if indigestion, or other gut upsets, occur.
They should be taken for a minimum of four weeks before discarded as ‘no good.’ My
usual regime is to prescribe Naprosyn 500 mg. tablets, one with breakfast and one with
the evening meal. Alternatively, Brufen 800 mg. CR tablets, two with the evening meal.
Tricyclic Antidepressants (TCA) - These were developed about fifty years ago as
antidepressants. Much more recently, it has been found that TCA’s in much lower
doses than required for depression can have an effect on cells in the spinal cord and
thus reduce pain messages reaching the brain. Perhaps ‘TCA’ should stand for “Tri
Cyclic Analgesics …. They may be accepted better! They also can have a sleepy ‘side
effect’. So, by taking TCA’s regularly in the evening, pain gradually reduces and sleep
improves.
I find that patients with PPP are often very sensitive to the effects of medication and so I
start them at a very low dose and build up as required.
My usual approach is to use Amitriptyline tablets 10 mg. and start with half a tablet (5
mg.) about two hours before bed. After one week the dose is increased to 10mg. Two
weeks later the dose is increased to 20mg. If there isn’t an adequate response at this
level the dose is increased by 10 mg. per fortnight until a full night’s sleep is obtained, or
a dosage of 50mg. is reached. In most cases there doesn’t appear to be a lot of
advantage in increasing the dosage higher than this.
I find, in practice, that most people respond to doses between 10-30mg. The time of
taking the tablets is designed to coincide with the maximum ‘sleepy’ effect of the TCA.
If you feel sleepy in the morning just take the tablet an hour or two earlier in the evening.
By you adjusting the timing and the dosage, the maximum advantages of the medication
can be obtained to suit you.
At the low dosages involved side-effects are unlikely to be troublesome, but there are
several TCA’s in the same ‘family’ and these can be substituted if necessary eg doxepin
SUMMARY:
The management (note I didn’t use the word ‘cure’), of PPP is complicated, and time
consuming. It requires a lot of commitment and hard work.
Results seem better if several aspects are tackled at the same time, rather than trying
each in turn in a sequential way.

There is no simple remedy or magic cure. (If there was a simple cure I would be rich
and famous and sure wouldn’t be working here!)
However, with understanding of the causes of PPP, the aims of treatment, and the
guidance of people experienced in pain management, improvement can be expected.


Write your questions here:
management. They include recognition of pain causing events and their avoidance, relaxation techniques, stress management techniques, etc. WORKPLACE (AND HOME) MODIFICATION: There will be many things you do that can make your pain worse that are caused by bad design, and inappropriate use of equipment. Recognition, and the subsequent altering, of these factors can play a big part in improving pain management. Examples include pillow design and bed construction, work-station design, the way you drive a vehicle, the way you hold a power tool, the way you hold the needles when knitting etc. An Occupational Therapist can advise on engaging in self care, work and leisure activities. MODIFICATION OF OTHER FACTORS: Several other factors are known to play a part in the maintenance of PPP. Modification of these can help improve the overall picture. They include: * Sleeping Tablets - although a person with PPP usually has poor sleep patterns, the use of ‘standard’ sleeping tablets is not supported at the pain clinic, as they all contain substances that can ultimately make pain worse. (See TCA’s later). Alcohol - initially, alcohol can appear to deaden pain and help sleep. However, there is a price to pay for this. Alcohol is a depressant and although it may appear to help in the initial stages, it reduces the capacity to cope with PPP in the long term. Nicotine - nicotine is a neurotransmitter substance (one that helps nerves to conduct) in its own right. Taking it into your system in the form of smoking will only contribute to the pain. (I’m not saying you must stop smoking, but you must realise that every time you light up a cigarette you are undoing the good that you are achieving with the rest of the treatment programme). Caffeine - caffeine is found in coffee, tea and ‘colas.’ This substance affects nerves and blood vessels, and consequently, affects pain. A recommended maximum amount of caffeine is in the order of four large cups of tea or coffee daily. Less than this is thought to be even more desirable. Recreational Drugs - there is no evidence that ‘recreational drugs’ help reduce PPP in the long term. Indeed, the evidence to date suggests only long term problems with illegally obtained, non-prescription drugs, so their use in PPP is not supported at the pain clinic. While there has recently been a lot of publicity in the media about the use of Marijuana for pain, there is, to date, no hard scientific data available that supports the claims made that persistent pain is helped by taking this drug. Cold Weather - many patients with PPP complain that cold weather seems to make their pain worse. Consequently, keeping yourself warm makes good sense. This may include wearing thermal underwear (eg polypropylene), and avoid sitting in drafts. Surgery - surgery has a place for well-defined pain problems that surgery is
known to help, such as, nerve entrapment (that is confirmed by nerve conduction
studies), or for prolapsed disc with clear-cut signs of nerve damage. But to carry
out surgery in an area that is supplied by nerve cells in the spinal cord that are
already subject to ‘wind-up’ is to risk increasing the excitation of these cells even
more, and thus make the persistent pain worse. Hence, pain cannot be cut
out!
nervous system and stop the amplified pain messages reaching the brain can help with persistent pain. Some medicines can actually make the pain problem appear worse, eg using sleeping tablets, or taking pain killers ‘as a last resort.’ (by “holding out” and not taking medication early enough, much higher doses of medicines may be required to help bring the pain under control) At the end of this handout is a list of common medications that you might be asked to try, and the recommended way of taking them to achieve the best results. PHYSIOTHERAPY: Most of the people seen for PPP have had ‘physio’ and say that it didn’t help much; or was okay at the time but ‘didn’t last’ etc. The role of physiotherapy here is different and will include the following: a) Teach about chronic pain and how it can be maintained by lifestyle etc. The role of muscles in maintaining PPP (myofascial pain) The importance of general exercises and the need to do the correct ones regularly. Aerobic programme (exercise that increases blood flow around the body). Stretching programme for specific muscles Preventative advice and management, including: Pain control self-management, including the correct use of heat, Transcutaneous Electrical Nerve Stimulators (TENS), posture and pacing at work and home. Hands on modalities by Physiotherapist, including: TENS, Acupuncture, Trigger Point needling, Ultrasound therapy, Short Wave diathermy, etc. PHYSICAL EXERCISE: The guidance for choosing the most suitable type of exercise for you will come from the Physiotherapist, and will aim at raising the heart rate and increasing the blood circulation (aerobic) around the body. It is important to start slowly and build up gradually. Suitable exercises may include brisk walking, jogging, bike riding, stepping, swimming, aqua-jogging etc. Such regular exercise will help improve chronic pain, sleep etc. PAIN MANAGEMENT SKILLS: These are techniques for coping in an appropriate way when the persistent pain is present, and are best taught by a clinical psychologist with a special interest in pain Lack of understanding of the processes involved in the causes and maintenance of the pain, by the patient, their family, and their employer and workmates. Lack of sleep making coping difficult and the pain overwhelming. Experiencing delays with acceptance of there being a problem and receiving appropriate help from employers and the ACC. Loss of hope of a “cure” as cycles of hope and despair occur with each new treatment’s suggestion, implementation and failure. The use of ‘drugs’ that modify the brains responses to nerve signals. These can include: - alcohol, nicotine, caffeine, and recreational drugs such as cannabis.
DIAGNOSIS:
The diagnosis of ‘persistent pain problem’ (PPP) is arrived at after a full history of the
problems has been taken, a full medical examination has been carried out, and other
possible causes eliminated. This should be done with a multidisciplinary approach, ie a
group of people with similar interests but different skills working together in a pain relief
clinic concept.
MANAGEMENT
It must be stated at the outset that a ‘cure’ is not a realistic goal in PPP, due to
secondary events being able to trigger the pain’s recurrence. However, what is
attainable is a considerable improvement in symptoms, with a reduction in pain, and a
better quality of life.
Most of the advice that follows is just that - advice - and YOU must decide whether you
wish to apply this advice to your situation. You will be given assistance, based on our
current knowledge, but only you can put in the effort needed to reverse the pain
processes.
Areas that need attention include:
*
modification of activities, and the intake of substances believed to worsen pain. Now to discuss each of these in turn:- MEDICATIONS: Medications play an important part in helping to bring PPP under control. With the increased understanding of the many factors involved in PPP a more rational use of medicines can occur. For example medicines that reduce the pain messages to the brain can allow a better nights sleep, or medicines that stabilise cells in the central PROBLEMS WITH PERSISTENT PAIN
DEFINITION
Pain that has persisted for more than three months is termed ‘persistent pain’, (but in
practice, acute pain that has gone on longer than one month should be seen as
‘persistent’).
WHO DOES IT AFFECT?
Up to one quarter of the population who have acute pain may have the disposition to
develop a persistent pain condition. There is some evidence that this may be
genetically determined. At present, it is not possible to predict who will develop this
problem.
HOW DOES IT HAPPEN?
One of the roles of the nervous system is to protect the body from initial, and then
further, damage. For example, if you break a leg the pain stops you from walking on it
while healing takes place. As you heal the pain subsides and function returns. If
however, the pain does not settle and is still present after healing is complete, then this
pain is abnormal, and no longer serves a useful, protective, purpose.
This is what happens in persistent pain. The pain persists long after its usefulness has
finished and is not thought to be signalling further tissue damage.
The nerves, and their junction cells, that carry messages to the brain can become
‘sensitised’ and send abnormal messages. These are usually messages of pain, but
can also include temperature, touch, itch, etc. So part of the problem can include
burning or cold sensations, light touch that can invoke pain, an intense itching, etc.
Also, while the brain is good at recognising these different sensations (pain, burning,
cold, itch etc) it has difficulties in determining where the sensation is arising from . an
extreme example of this is phantom limb pain, where a person can experience pain in a
limb that has been removed . I will return to this when answering the comment I often
hear, “I just want someone to cut out my pain .”
So, the important message at this stage is the pain is always real, only the site where
it is perceived to be coming from may not be accurate.
Although most of the original pain signals we have been talking about arise from the
peripheral nervous system, it appears that in persistent pain problems, the pain is
maintained by cells in the central nervous system (spinal cord, brain). These cells
undergo a ‘wind-up’ phenomenon which results in the pain getting more and more
severe. I see it like a telephone exchange, a relay along the line, where a small signal
results in many signals sent out to the next exchange.
By the time the signal has reached the brain it registers a large amount of pain from a
small signal at the periphery. With time, the telephone exchange can keep on sending
many signals out when no signals are coming in . in other words, the brain can get
messages it interprets as pain, often severe, that no longer depend on the original
irritation that started the process, but rather, arise from cells of the central nervous
system itself.
Of course, this is not the total story . there are many other factors which contribute to
the pain.
With pain comes muscle tightness and spasm; stresses on tendons, nerves and joints
which can increase the pain and add to the ‘wind-up’.

Source: http://www.occmedpaindoc.co.nz/files/persistant_pain_2007.pdf