Intrathecal drug delivery, or “pain pump,” is a method of giving medication directly to your spinal cord. The system uses a small pump that is surgically placed under the skin of your abdomen and delivers medication through a catheter to the area around your spinal cord – similar to an epidural that women may have during childbirth. A pain pump may be a treatment option if all other traditional methods have failed to relieve your long-term symptoms. Because the medication is delivered directly to the spinal cord, your symptoms can be controlled with a much smaller dose than is needed with oral medication. The goal of a drug pump is to better control your symptoms and to reduce oral medications; thus reducing their associated side effects.
What is an intrathecal drug pump?
The fluid filled space around your spinal cord is called the subarachnoid or intrathecal space. Cerebrospinal fluid (CSF) flows through this area, bathing and protecting your brain and spinal cord. An intrathecal drug pump works much more efficiently than oral medication because it delivers medicine directly into the CSF, bypassing the path that oral medication takes through your body. In fact, you generally need about 1/300 the amount of medication (morphine or baclofen) with a pump than when taken orally.
The pump is a round metal device about the size of a hockey puck that is surgically implanted beneath the skin of your abdomen. A small plastic tube, called a catheter, is surgically placed in the intrathecal space of the spine and is connected to the pump (Fig. 1). A space inside the pump called the reservoir holds the medication.
The pump is programmed to slowly release medication over a period of time. It can also be programmed to release different amounts of medication at different times of the day, depending on your changing needs. The pump stores the information about your prescription in its memory, and your doctor can easily review this information with the programmer. When the reservoir is empty, the doctor or nurse refills the pump by inserting a needle through your skin and into the fill port on top of the reservoir.
This therapy is completely reversible if you should ever decide to have the pump removed.
Who is a candidate?
You may be a candidate for intrathecal drug delivery if you meet the following criteria:
- Conservative therapies have failed
- You would not benefit from additional surgery
- You are dependent on pain medication
- You do not have psychological problems
- You have no medical conditions that would keep you from undergoing implantation
- You are not allergic to any of the drugs used in the pump
- You have had positive response with a trial dose of medication