Intrathecal Baclofen Therapy

Intrathecal Baclofen Therapy (ITB) for Treating Spasticity

 

About Intrathecal Baclofen Therapy

ITB Therapy (Intrathecal Baclofen Therapy) for the management of severe spasticity uses an implantable infusion system to deliver precise amounts of Lioresal® Intrathecal (baclofen injection) directly to the intrathecal space via a surgically implanted pump and catheter.

The precise mechanism of action of baclofen as a muscle relaxant and antispasticity agent is not fully understood. Baclofen inhibits both monosynaptic and polysynaptic reflexes at the spinal level, possibly by decreasing excitatory neurotransmitter release from primary afferent terminals, although actions at supraspinal sites may also occur and contribute to its clinical effect. Baclofen is a structural analog of the inhibitory neurotransmitter gamma-aminobutyric acid (GABA), and may exert its effects by stimulation of the GABAB receptor subtype.2

Lioresal Intrathecal, when introduced directly into the intrathecal space, permits effective CSF concentrations to be achieved with resultant plasma concentrations 100 times less than those occurring with oral administration.2

In people, as well as in animals, baclofen has been shown to have general CNS depressant properties as indicated by the production of sedation with tolerance, somnolence, ataxia, and respiratory and cardiovascular depression.2

Baclofen has also been shown to have general CNS depressant properties such as sedation, which suggests activity at supra spinal sites as well.

Indications

Lioresal Intrathecal is indicated for use in the management of severe spasticity of spinal cord origin or cerebral origin.

Contraindications

Hypersensitivity to baclofen. Lioresal Intrathecal is not recommended for intravenous, intramuscular, subcutaneous, or epidural administration.

When infection is present; when the pump cannot be implanted 2.5 cm or less from the surface of the skin; when body size is not sufficient to accept pump bulk and weight; when contraindications exist relating to the drug; drugs with preservatives. Do not use the Personal Therapy Manager accessory to administer intrathecal baclofen or to administer opioid to opioid-naïve patients or to administer ziconotide.

References

  1. www.MDVU.org, web site accessed 12/08/08 http://www.wemove.org/spa/spa_epi.html
  2. Lioresal® Intrathecal (baclofen injection) Drug Package Insert.

Treatment & Diagnosis

Spasticity is an abnormal increase in muscle tone caused by injury of upper motor neuron pathways regulating muscles. Spasticity may be a result of multiple sclerosis (MS), cerebral palsy (CP), stroke, brain injury, or spinal cord injury.

Although the pathophysiology of spasticity is not completely understood, it is most commonly defined clinically as "...a motor disorder characterized by a velocity-dependent increase in tonic stretch reflexes ('muscle tone') with exaggerated tendon jerks, resulting from hyperexcitability of the stretch reflex, as one component of the upper motor neuron syndrome."2 The velocity-dependent nature of spasticity distinguishes it from other forms of hypertonia, such as dystonia and rigidity.3

Spasticity can have a distressing effect on function, comfort, and caregiving. Spasticity may result in musculoskeletal complications, incoordination, loss of function, pain, and permanent muscle shortening or contracture.

Treating spasticity may:

  • Improve gait, hygiene, activities of daily living, and ease of care
  • Decrease spasm frequency, pain, and fatigue
  • Promote tone reduction, increased range of motion, and joint position
  • Increase patient mobility
  • Complement other interventions, such as physical therapy, occupational therapy, and speech therapy

It can be difficult to effectively control severe spasticity. While physical rehabilitation and oral pharmacologic treatments work for many patients, some patients may not experience enough relief using these treatments alone. In addition, some patients encounter intolerable side effects from systemic medications. Patients who are unresponsive to oral baclofen or who experience intolerable central nervous system (CNS) side effects from oral medications may benefit from ITB Therapy. ITB Therapy can significantly decrease severe spasticity and spasms4-12

References

  1. www.MDVU.org, web site accessed 12/08/08 http://www.wemove.org/spa/spa_epi.html
  2. Lance JW: Synopsis. In: Feldman RG, Young RR, Koella WP, eds. Spasticity: Disordered Motor Control. Chicago: Year Book Medical Publishers. 1980: 480 485.
  3. Sanger TD, Delgado MR, Gaebler-Spira D, Hallet M, Mink JW; Task Force on Childhood Motor Disorders. Classification and definition of disorders causing hypertonia in childhood. Pediatrics. 2003;111 (1):e89-97.
  4. Francisco GC, Boake C. Improvement in walking speed in poststroke spastic hemiplegia after intrathecal baclofen therapy: a preliminary study. Arch Phys Med Rehabil. 2003;84(8):1194-1199.
  5. Meythaler JM, Guin-Refroe S, Brunner RC, Hadley MN. Intrathecal baclofen for spastic hypertonia from stroke. Stroke. 2001;32(9):2099-2109.
  6. Ivanhoe CB, Francisco GE, McGuire JR, Subramanian T, Grissom SP. Intrathecal baclofen management of poststroke spastic hypertonia: implications for function and quality of life. Arch Phys Med Rehabil. 2006;87(11):1509–1515.
  7. Gilmartin R. Intrathecal baclofen for management of spastic cerebral palsy: multicenter trial. J Child Neurol. 2000;15(2):71-77.
  8. Penn RD. Intrathecal baclofen for spasticity of spinal origin: seven years of experience. J Neurosurg. 1992;77(2):236-240.
  9. Albright AL, Gilmartin R, Swift D, Krach LE, Ivanhoe CB, McLaughlin JF. Long-term intrathecal baclofen therapy for severe spasticity of cerebral origin. J Neurosurg. 2003;98(2):291-295.
  10. Coffey RJ, Cahill D, Steers W. Intrathecal baclofen for intractable spasticity of spinal origin: results of a long-term multicenter study. J Neurosurg. 1993;78(6):226-232.
  11. Ordia JI, Fischer E, Adamski E, Chagnon KG, Spatz EL. Continuous intrathecal baclofen infusion by a programmable pump in 131 consecutive patients with severe spasticity of spinal origin. Neuromodulation. 2002;5(1):16-24.
  12. Becker R, Alberti O, Bauer BL. Continuous intrathecal baclofen infusion in severe spasticity after traumatic or hypoxic brain injury. J Neurol 1997; 224(3): 160-166