Baclofen is a muscle relaxant medication used to treat spasticity and dystonia. Baclofen works at receptor sites (called GABA) in the spinal cord and the brain. It is commonly taken in a tablet form however its effectiveness is limited as side-effects are common as dose is increased. By infusing the baclofen directly into the area around the spinal cord (the intrathecal space) it goes right to where it is needed. A much lower dose can therefore be used with a much greater effect. In this way, side effects of the medication can be limited.
How it works
Intrathecal baclofen treatment (ITB) has been used for people with severe dystonia or spasticity since the early 1990’s. Many reports have been published to support its use. In the literature, ITB therapy has been shown to improve spasticity and dystonia for children with cerebral palsy.
Improvements in quality of life may be seen for both child and family. Children may experience an improvement in pain management and sleep. Decreased spasticity or dystonia may lead to an improvement in ease of washing and dressing for a child with severe cerebral palsy. Seating and comfort when sitting may also be improved. Some children may also experience an improvement in functional skills.
The pump system
The infusion system consists of three parts:
- The pump (size of a hockey puck, about 2.5cms thick, weighing 180g). This is surgically implanted in the abdominal area under the skin. The pump delivers a controlled amount of baclofen to provide a continuous infusion. The computer system inside the pump can be programmed to give varying doses as needed throughout the day.
- The catheter. This carries the drug from the pump reservoir to the spinal cord.
- The control system. This is a hand held telemetry device which allows for changes in drug dosing by placing the device over the skin where the pump is implanted. To refill the pump, a nurse will place a needle directly into the pump reservoir and inject baclofen.
Medtronics, the makers of intrathecal baclofen pumps, provide written resources and DVD’s for families. These will be made available to you.
While drug related side effects are less common than with baclofen tablets the reported complication rate of ITB is high (between 20 and 50 per cent).
Problems tend to occur due to infection of the implantable device (including infection of the catheter that may lead to meningitis), catheter malfunction and pump malfunction.
Dosing errors causing overdose and under-dose can also occur when doses are changed or the pump is re-filled.
Suitability for ITB treatment
Children with spasticity or dystonia are eligible to be considered for ITB therapy when other treatments have been tested and shown to be insufficient. The goals of the child and family for ITB usually relate to improvement in comfort or ease of care.
Specific criteria for consideration of ITB include:
- Severe spasticity or dystonia that significantly impacts upon quality of life where other options for spasticity management have been trialed and shown to be inadequate.
- Children must be of sufficient size and nutritional status to support the size of the pump implanted under the skin on the abdominal wall.
- Families must be aware of the potential for complications and undertake to bring children to the Queensland Children’s Hospital for urgent review when needed. For children who live outside of Brisbane, support from local paediatric services is necessary.
- Children with intrathecal baclofen pumps need to be seen regularly for dosage changes, pump refills and ongoing monitoring for change. Families therefore need to commit to the regular hospital visits that this will require.
Queensland Paediatric Rehabilitation Service
Queensland Children’s Hospital
Level 6, 501 Stanley Street, South Brisbane 4101
t: 07 3068 2950
t: 07 3068 1111 (general enquiries)
f: 07 3068 3909
In an emergency, always call 000.
If it’s not an emergency but you have any concerns, contact 13 Health (13 43 2584). Qualified staff will give you advice on who to talk to and how quickly you should do it. You can phone 24 hours a day, seven days a week.
Offers information from both medical and patient perspectives for children and adults with ITB pumps.
Gives up-to-date information on spasticity and dystonia management including ITB.