Chronic Pain: Implantable Pain Control Devices (cont.)

KAPURAL:
Yes, exactly. The trial is essential to see how successful stimulation will be.

MODERATOR:
So a trial lasts seven to 14 days?

KAPURAL:
Trials should last at least seven days. The reason I do recommend a trial longer than seven days is that we can better assess improvement in functional capacity of the patients.

MODERATOR:
Is there any comparable trial for intrathecal drug delivery systems?

KAPURAL:
Yes, and we do it at the Cleveland Clinic inpatient, in the hospital. We place a temporary catheter in the patient's back and admit them for two or three days to adjust the level of medication delivered. When they have satisfactory pain relief, we pull the catheter out and send them home and set them up later for implant of the pump.

MODERATOR:
Can you explain how the stimulators are implanted?

KAPURAL:
The lead is positioned either by percutaneous approach or surgical approach. The percutaneous approach uses an epidural needle to position a tiny (like a hair), lead into the epidural space. That lead may have multiple electricals on it.

Once the lead is positioned in the epidural space, small cuts are made, less than one inch, in the middle of the back and about an inch and a half in the buttock area. This is where the battery will be positioned, or the generator. Later the generator and the lead are connected together with a connector extension under the skin.

During the procedure the patient is awakened and stimulation tried to make sure that they have perfect coverage of all of the painful areas, with what we call pleasurable tingling; that's the feeling they have from the stimulator.

Once everything is in place, both of those incisions are closed and patients stay for a short time in recovery and then go home.

"Over the last six years the devices became so well made that we are now very comfortable in implanting, especially spinal cord stimulating systems. "

MEMBER QUESTION:
Could such a device be used for the chronic pain of osteoarthritis?

KAPURAL:
Well, the electrical stimulation no, but the intrathecal pump, yes, it has been used before and it can be used in severe arthritis.

MEMBER QUESTION:
Are implantable devices appropriate for chronic migraines (daily pain that varies from dull to severe/throbbing)? Has an implantable device ever been used to prevent or abort chronic migraine attacks?

KAPURAL:
First of all, it has to be determined what types of headaches. If this is a classical migraine, my answer is no, but if you have a headache in the back of the head, occipital headaches, we do implant here at the Cleveland Clinic some of those peripheral nerve stimulators for headaches in the back of the head.

MEMBER QUESTION:
How effective are the spinal cord stimulators? If you insert them in 100 patients, how many will get significant improvement? I will have one inserted next month.

KAPURAL:
There are quite a few studies looking into the success rate of the spinal cord stimulation. It depends on what kind of disease the patients have, but studies from the Cleveland Clinic on RSD show a success rate of about 60 to 70 percent. On the other hand, if you have failed back surgery syndrome, the success rate is somewhat lower, in the range of 50 to 60 percent.


MODERATOR:
For those not familiar with these systems, can you please explain how they work?

KAPURAL:
The intrathecal pump is just a very expensive pump that slowly delivers concentrated morphine, local anesthetic, or other medication into the intrathecal space, which is nearby the spinal cord. By delivering those medications, the pain receptors in the spinal cord get blocked, therefore the pain subsides.

MODERATOR:
What is the advantage to this method of drug delivery?

KAPURAL:
The patients are frequently more awake, function better, receive much, much less systemic medication, and frequently they are more cost effective than oral or IV medication, in the long run, for severe chronic pain.

MEMBER QUESTION:
With people like me already taking a lot of painkillers, can we switch to the pump and not have withdrawal symptoms?

KAPURAL:
That's a good question. We develop a whole protocol for how we do this here at the Cleveland Clinic. The patient comes in and we transition them slowly to intrathecal infusion. That's not the major problem.