Just because the patient has subjective complaint of pain, he is no candidate for infusion pump. Just because the patient has been taken off strong medications and still has complaints of pain, that does not pass him for infusion pump. Just because the patient has had multiple operations and has a failed back or multiple surgical procedures on damaged nerve areas, that does not pass him as a candidate for infusion pump.

If the patient is using the pain has a handle to have primary or secondary gain, or if the patient has a constant complaint of pain without any objective findings, the patient can not be considered an infusion pump candidate.

On the positive side, what prompts us to consider infusion pump is as follows.

The infusion pump is usually installed in advanced cancer patients as a palliative treatment. In a small minority of noncancerous patients infusion pump is indicated because of the following reasons.

In our practice, which consists of a tertiary referral practice, we do not get fresh cases of straight forward cervical or lumbar disc herniation, acute, subacute or chronic nerve injuries, or patients with a short history of pain due to different types of injuries.

What we have is the cases that are like a used car, already dumped into the junkyard. These are the patients who not infrequently have had multiple operations, have been to pain clinics, have had to be detoxified, and every body has given up on them.

Even this type of patient is not automatically a candidate for the infusion pump. The patient has to go through the procedures of detoxification, placebo treatment, other types of treatment for

chronic pain such as large doses of antidepressants and anticonvulsants, and even then the patient will not be a candidate for infusion pump.

The key to the patient becoming a candidate for infusion pump is the word OBJECTIVE. This usually does not mean a positive MRI or CAT scan or x-ray finding. Already these patients have had multiple operations and any kind of positive abnormality on MRI such as disc herniation has already been repeatedly operated on. So anatomically these patients look pretty good. In our study of the chronic pain patients, (I am enclosing a test book that I have written on the subject for your review) disc herniation is the source of the pain in less than one third of such patients. Our group shows 26% of the patients have such severe intractable pain due to disc herniation and Dr. Rosomof's study in the pain clinic in Miami shows 28% of such patients having such severe pain due to disc herniation.

By objective findings we mean NERVES INJURIES in different forms. The nerve injuries are usually not in the form of impingement or compression by a bone or disc. These usually consist of the following injuries.

1. Nerve roots contusions.

2. Spinal canal arachnoiditis.

3. Crush injuries.

4. Ephaptic electric short between the sympathetic and somatic

nerves. (This subject is discussed in detail in the enclosed

textbook.)

5. Advanced cases of reflex sympathetic dystrophy.

6. Electrical injuries, chemical injuries, or sharp object

injuries in the "watershed zones" over the dorsum of the foot

or hand or over the ankle, elbow, or knee. In such watershed

zones, the adjacent sensory dermatomes from different parts of

intractable pain.

The type of patients mentioned above usually have gone through years of treatment for chronic pain, have had multiple usually unnecessary operations, and have been tried on every kind of treatment such as spinal canal stimulators. Unfortunately, the SPINAL STIMULATORS are the stylish forms of treatment now a days for such intractable chronic pain patients.

Enclosed you will find a copy of my letter to Dr. Urechio regarding spinal stimulators that summarizes the reason for failure of such operations. It is going to take a few years before the people realize that they are adding more sources of pain to the patient's complex chronic pain, and they are wasting everybody's time and money with these stimulators.

Many other such patients have undergone rhizotomy, tractotomy, and neurectomy. Such operations may be helpful in advanced fatal cases of cancer just to provide a few months of relief,

but the invariably practically always aggravate the chronic pain by becoming a new source of pain in the area of surgical scar. In such patients the OBJECTIVE SIGNS are not hard to find. The key is the clinical correlation. The patient may have a small electric short between the somatic and sympathetic nerve causing severe pain and yet at the same time, the patient may have an already healed disc herniation that is objectively quite impressive, but is not related to his pain. The conventional wisdom of common practice goes after the disc herniation and removal of an asymptomatic disc in such a patient will only create a new iatrogenic source of pain without fixing the original source of pain.

The key is that the OBJECTIVE FINDINGS SHOULD GENERATE AND REPRODUCE THE SAME PAIN THAT THE PATIENT IS BEING TREATED FOR.

The useful objective tests consist of:

1. A careful neurologic examination with judicious clinical

correlation.

2. Neurophysiologic tests such as EMG, evoked potential, bone scan

thermography, etc.

3. Proper nerve blocks and test treatments to objectively and

physiologically prove or disprove that the patient's pain is

related to the abnormalities found on paraclinical tests.

Finally, such patients have to undergo extensive proper treatment for chronic pain which consists of but is not limited to the following forms of treatment.

1. Discontinuation of narcotics.

2. Discontinuation of Benzodiazepines.

3. Proper use of antidepressants which are the treatment of choice

for management of chronic pain.

4. Extensive physical therapy.

5. As is discussed in the enclosed textbook of chronic pain, we

prefer treatment with ACTH to stimulate the patient's own

endorphines and corticosteroids to counteract the pain.

6. Correction of any other hormonal disturbance such as the use of

Estrogen for menopause, the use of Calcitonin for osteoporosis.

7. A proper diet instruction (the diet book that we give to the

patients is enclosed).

In our experience, the use of Stadol which is a Morphine agonist antagonist, and is not even a controlled drug is quite helpful in facilitating the discontinuation of addictive narcotics.

Of over 500 severe intractable noncancerous chronic pain patients that we have reviewed, only 38 so far have passed the above criteria and have become the candidates for infusion pump treatment.

Even then, the infusion pump is tried for 1-5 days on a trial basis with placebo versus narcotic medications and then if it works the patient undergoes the permanent treatment

The first part of the question that is addressed to us in regarding the infusion pump is the fact that we have gone through such a tedious trouble to detoxify the patient and then we recommend a form of narcotic treatment on a permanent basis (Morphine Pump).

I am enclosing the information on Morphine Pump that we provide to the patients, physicians, and third party providers as a source of information. As the enclosed material reflects, the Morphine Pump is different from other forms of narcotic treatment due to the fact that:

A. The infusion pump provides a slow drip continuous small amount analgesic. This form of drip irrigation emulates the way the endorphine works. On the other hand, other forms of long term narcotic administration such as patient controlled anesthesia (PCF), Duragesic skin patch, IM subcutaneous IV, or oral narcotic administration expose the patient to a flood irrigation of large doses of narcotic followed by a significant withdrawal after a few hours.

During such withdrawal, the central nervous system is devoid of both exorphins and endorphines with the resultant alarm panic agitation and the sensation of pain even in the absence of any lesion originating the pain.

B. Most importantly the patient is being given the equivalent of one and a half to two days of standard narcotic dose in the pump to be dripped in 30 days. As a result, the patient is given 1/15 to 1/20 of the standard dose of narcotic.

This sharp reduction of intake of narcotics will prevent the inhibitory and suppressive effect that large doses of narcotics have on other CNS hormones such as Estrogen, antidepressants, and hypothalamic hormonal secretions. As a result, the patient does not end up having the side effects of insomnia, depression, suicidal tendency, a lack of desire for sex, and poor appetite.

In 5 of the 38 patients, superimposed infection in the area of foreign body insertion, has complicated the use of Morphine Pump.

Of the 5, 3 had reinsertion of the pump without any further complication. This was done after several weeks to a few months interval between the first and second

either not a candidate on one case and did not want to have the Morphine Pump reinserted on another case.

In one patient, extensive scar formation developed forcing the withdrawal of Morphine Pump.

In three patients, there was a significant degree of intolerance to the medication administered in the pump. In two out of these three patient, other medications such as Dilaudid and Fentanyl were tried and two were successful.

With this, approximately 10% complication adverse reaction and failure of the pump is compared to all the other treatments that the patient has already been exposed to which have been 100% failure.

The 38 pumps have been inserted in the past 9 years and practically half of them have been inserted in the past 2 years, so the long term effects of the pump have not been completely finalized.

I am enclosing the reference material that we have retrieved from the medical literature through the library computer facility of the University of Miami.

A brief summary of the review of literature reveals that whereas infusion pumps have been used for practically three decades for intractable cancer pain, they have been applied from chronic pain since 1978.

The standard narcotics such as Morphine and Dilaudid have been usually used and in some cases the water soluble Sufentanil has been used.

In chronic pain patients, the infusion pump has been most effective in patients suffering from pain below the shoulder level. The patients who suffer from craniofacial pain usually need lateral ventricular infusion pump inserted. This is usually given to the patients suffering from crainocervical cancer lesions.

The enclosed reference #13 published in the Journal of Neurosurgery by the researchers from Cleveland Clinic is quite informative and I will quote "intraspinal narcotic (usually intrathecal Morphine) infusions with implanted pumps are increasingly used in patients with intractable chronic pain not caused by cancer. In some patients, pain control is difficult with infusion pump. Seven patients with diagnoses of arachnoiditis, epidural scaring, and/or vertebral body compression fracture were treated with alternative solutions in an epidural route. For maximum flexibility, medtronic implanted programmable infusion pumps with catheters to T6-T10 were used, and pain was monitored by verbal pain scales. In three patients epidural infusions of Morphine in 0.5% Bupivacaine resulted in little or no pain relief without significant side effects (e.g., headache, nausea, or vomiting).

In these same patients epidural infusions of Sufentanil Citrate resulted in pain scale reduction of 92%, 82%, and 40% respectively, with no side effects. Four other patients found more effective pain relief when switched from initial Sufentanil Citrate infusion to Morphine Sulfate Marcaine. Pain scale reductions (with no side effects) were 92%, 76%, 59%, and 47% in these patients. Pain relief and minimal side effects with Sufentanil Citrate is theorized to result from its higher lipophilicity promoting local transdural diffusion to spinal cord and limiting upward diffusion to the brain stem. Sufentanil Citrate is also advantageous for programmable pumps because it is a hundred times more potent than Morphine and therefore allows long pump refill times and higher infusion doses. Although this study was done on a limited number of patients, Sufentanil Citrate and MS Marcaine in epidural infusions used in programmable infusion pumps for noncancer patients provide significant alternative drug combination and routes."

The references numbered 2,3,6,10,11, and 13 have limited their studies to the use of infusion pump in noncancerous intractable pain patients.

The literature also reflects limitations and side effects of such treatment. The craniocervical pain can not as easily be controlled by the infusion pump because of the suppressive effect of these medications on respiratory centers.

The complications have been outlined as headache as a rare complication, meningitis in two cases, and in one case they have had similar experiences as we have had in the form of granuloma formation at the tip of the catheter pressing on spinal cord. In the case of our patient developing such complication, removal of granuloma and replacement of the tube solved the problem.

We have compared 40 RSD patients who have been treated with spinal stimulators with 40 non-RSD patients who have been treated with spinal stimulators for chronic pain. The latter group consisted of patients who have had failed back, nerve roots contusion, lumbar arachnoiditis, and other forms of chronic pain in absence of RSD.

In the non-RSD group of patients, spinal stimulators were effective in management of chronic pain and to even a small extent suppressing the pain in 23% of the patients. The beneficial effect would last up to 18 months on the average, and then it would lose its effect.

In the RSD patient on the other hand, the success rate after 2 years follow-up was nil and the beneficial effect in helping the pain to even a small extent would last on an average of 3 1/2 to 4 months.

What was more significant in this study was that in the long run the insertion of metal in the spinal canal would act as a new source of RSD in over 4/5 of the patients suffering from the RSD to begin with.

One probable reason for the failure of the stimulators may be the fact that the stimulators are digital versus the pain being analogue in nature.

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