Intrathecal Pump

An intrathecal pump is a medical device used to deliver very small quantities of medications directly to the spinal fluid of a human being. Medications such as baclofen, morphine, or ziconotide may be delivered in this manner to minimize the side effects often associated with the higher dosages commonly found in oral medications of the same type.

People with spastic diplegia or other forms of spasticity, or people in intolerable pain and nociception, who cannot tolerate side effects of the higher-dose oral medications of the same medication type, are potential candidates for that medication being administered via an intrathecal pump. In about 5% of patients, the intrathecal baclofen route has no effect on the nervous system.

The intrathecal pump consists of a metal pump which stores and delivers the medication, and a catheter which delivers the medication from the pump to the intrathecal space in the spine where the medication takes effect. Two types of pumps are available: a constant rate pump delivers the medication at a constant rate, and a programmable pump delivers the medication according to a rate determined by a programmable computer program.

The implantable medical device requires a surgical procedure; a surgeon usually performs a trial intrathecal injection or a temporary intrathecal pump to determine if the medication works to begin with, and thus if a pump is appropriate. A permanent intrathecal pump is then implanted if the patient derives at least 50% improvement in his or her symptoms.

Despite the potential benefits of the intrathecal pump, complications from the implantation can occur even when the initial implantation is successful for several years in a row. Complications from the surgery itself are actually very rare in the present day — infection and excessive bleeding during the surgery, spinal cord injury during the surgery, or catheter fracture or migration on the operating table do exist as risks, but typically do not happen. One potential post-op complication is the malfunction of the pump, which can occur immediately after surgery or several years later. Alternatives to intrathecal pumps include rhizotomy or stable oral doses of the medication.