Intrathecal Pain Pump
An intrathecal pain pump is a method of delivering pain medication directly to a patient’s spinal cord. The system uses a small pump that is surgically placed under the skin of the abdomen and delivers medication through a catheter into the area around the spinal cord. A pain pump may be a treatment option if other traditional methods have failed to relieve long-term symptoms of chronic pain. Because medication is delivered directly to the spinal cord, symptoms can be controlled with a much smaller dose than what is needed with oral medication. The goal of an intrathecal pain pump is to better control a patient’s symptoms while drastically reducing side affects noted with oral medications.
An intrathecal pain pump works much more efficiently than oral pain medication because it delivers medicine directly into the cerebral spinal fluid, bypassing the path that oral medication takes through the body. In fact, the potency of the medication is about 100-300x more with the 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 the abdomen. A small plastic tube, called a catheter, is surgically placed in the intrathecal space (the sac of fluid around the spinal cord) and is connected to the pump. A space inside the pump called the reservoir holds medication, usually enough for several months.
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 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.
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 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
Determining whether an implantable drug pump will be a beneficial pain management option for you is a complex process. Before a permanent pump can be implanted, you must undergo a trial to determine if the device decreases your level of pain. Depending on your particular condition, one of the following screening tests will be necessary:
- Single injection: you will receive one injection of intrathecal medicine (morphine) through a spinal injection.
- Multiple injections: you are given multiple injections over a series of days by either a lumbar puncture or catheter.
- Continuous trial: a catheter is placed in the correct area of your spine and connected to an external pump. The dose is increased every two hours until you notice pain relief.
During the trial, Pain Management Specialists at Virginia Spine Institute will gather information about the best location for the catheter and the type and amount of drug that works best for you. If the trial is successful, you will be scheduled for surgery.
Side effects for intrathecal drug pumps are minimal, although they do exist. As with all surgeries, complications may include infection and bleeding. The catheter could move or become blocked, or the pump could stop working which is rare. Accumulation of fluid (cerebrospinal fluid leak) can occur around the pump causing a clear watery discharge from your incisions and cause a headache. These leaks are usually self limited, but may require a drain. Reasons for removal of the device include infection, failure to relieve pain, and patient misuse.
Side effects from the drugs (over or under dose) may include respiratory depression, twitching, muscle spasm, urinary retention, constipation, nausea, vomiting, dizziness, anxiety, depression, and edema. Depending on how much medication the pump delivers, the battery will eventually need to be replaced every five to seven years.