SPINAL DRUG INFUSION (INTRATHECAL DRUG THERAPY OR ITD)
A spinal drug infusion system is a special pump that can be implanted to deliver pain-relief or spasticity relief medication directly into the spinal fluid through a small tube. This is a treatment method for patients experiencing chronic, intractable pain or spasticity that has not been alleviated through more conservative methods. The spinal infusion system reduces patients’ reliance on oral medications because it can provide strong pain relievers directly to the pain receptors of the spinal cord to achieve substantial relief. Infusion of spasticity reducing medication (baclofen) can also be infused via these systems to treat muscle tone abnormalities associated with central nervous system injury.
Candidates for Intrathecal Drug Therapy
Patients who may benefit from intrathecal drug therapy include those with pain from cancer, failed back syndrome, complex regional pain syndrome, and other forms of intractable pain that cannot be adequately controlled with pain medication. Patients who may benefit from intrathecal drug therapy also include those with severe muscle spasticity that can occur after a stroke, spinal cord injury or neurological degenerative diseases. Patients must be free of allergy history of potential medications that would be place in the pump.
Spinal Drug Infusion (Intrathecal Drug Therapy) Procedure
The procedure for intrathecal drug therapy is two stages. The first is the injection of a trial drug either pain medication such as morphine or the muscle relaxant baclofen to test the relief of patient symptoms to the medication and for lack of side effects. This done in the office via placement of a small spinal needle into the spinal canal. It is usually not uncomfortable and involves a brief office observation stay to assure safety. If symptoms are relieved, then the permanent implantation procedure is done in the hospital outpatient department done under local anesthesia with sedation provided by an anesthetist. There is a small incision in the midline of the upper lumbar spine for catheter placement done via a needle. There is an incision where the pump will be located either on the abdomen or in the upper flank or buttock. The procedure takes about an hour and a half with most patients being discharged home an hour or so after reaching the recovery room. The pump will be filled for the first time in the office about one week after the implantation surgery and then every 2 months after that to assure fresh medication potency.
Risks of the Spinal Drug Infusion
Side effects and complications of surgery can infrequently occur including heart attack, cardiac arrest, stroke and blood clot formation. Other risks with intrathecal drug therapy include headache, bruising, and infection that could lead to meningitis. Loss of therapy can result in withdrawal symptoms which can be life threatening in some cases. Pumps rarely malfunction but the catheter can become occluded leading to loss of therapeutic effect. MRI can affect pump operation so pump health check by PCI providers or the manufacturer technician is advised after MRI is done. The pump will need to be replaced every 5 years as the battery becomes end-of-life at that point.
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