Several chronic spasmodic conditions like post-stroke spacisity and multiple sclerosis are successfully treated with intrathecal infusion of baclofen. It is used if the patient fails to respond to oral baclofen. The pump used for baclofen is the same as the one used for intrathecal opoids. In some cases, chronic pain and spasticity are treated by the combination of baclofen and morphine.
Trial phase: Most of the patients undergo a trial run of intrathecal baclofen injection. A test dose of baclofen of about 50 micrograms is usually injected in the spine. The patient is re-evaluated every 2 hours for about 8 hours after the injection to determine the extent of reduction in spasticity. If a significant change has been noticed, the patient will qualify for the intraspinal baclofen pump.
Pump Placement: The procedure will take 1.5-2 hours to insert the catheter in the spine and to implant the pump usually under the skin in the abdominal wall. The catheter is inserted through a needle into the spine and a small incision is made to anchor the catheter then tunneled under the skin from the back to the front where it is connected to the implanted pump. The pump is filled with medicine before insertion. The pump dose is increased on a regular basis for the next couple of weeks to control the spasticity.
Some patients can be monitored in the hospital 23 hours; others can be released after the procedure depending upon the health of the patient. Patient will return to the physician’s office 1-2 times a week to increase the pump dose, until the spasticity improves. Patient will notice a significant in spasticity, usually in 2-3 weeks.
Once the patient’s maintenance dose is determined, the patient will return to the office every 3-6 months to refill the pump. The pump refill is done in the office by placing a needle through the skin into the pump reservoir. Patient may require periodical dose changes depending upon the intensity of their spasticity.
The pump’s battery life is about 5-7 years; after that, the pump will need to be replaced with a new one by connecting it to an existing catheter.