Spasticity

Intrathecal Baclofen Therapy (ITB)

A programmable pump with a reservoir; a clear, flexible silicone catheter; and a programming device comprise the delivery system for intrathecal baclofen therapy (ITB™). Typically, candidates for ITB therapy have severe spasticity that does not respond to conservative treatment with medications or have intolerable side effects at therapeutic doses. The system is surgically implanted after the patient has responded favorably to a test dose of the intrathecally delivered medication. The pump, which is implanted subdermally, is usually refilled in the physician's office on a four- to eight-week basis, depending on the capacity of the reservoir and the dosage of ITB that is administered, and typically lasts for five or more years. The usual starting dose is 25 μg per day, with titration to efficacy, up to a maximum dose of 200+ μg per day.

Because ITB therapy delivers the drug directly to its site of action, much less baclofen is needed than when it is delivered orally. The drowsiness and sedation related to the use of ITB baclofen are much milder than when baclofen is delivered orally. However, approximately 5% of people develop infections that require temporary removal of the ITB therapy pump. Other equipment-related risks include pump failure, catheter kinking or breakage, or dislodgement of the catheter. Abrupt discontinuation of intrathecal baclofen is not advised—it may cause serious sequelae, including high fever, altered mental status, exaggerated rebound spasticity, and muscle rigidity. Rare cases have advanced to rhabdomyolysis, multiple organ-system failure, and death. To prevent withdrawal syndrome, families must be educated about the signs of baclofen withdrawal and have a plan to respond to possible emergencies.