Introduction: Intrathecal baclofen is an effective treatment for neurogenic spasticity. However, some patients develop refractory symptoms, presumably due to tolerance or incomplete treatment with baclofen alone. Clinically, these patients complain of refractory hypertonus or spasticity-related pain. In this study, we explore the efficacy of adding low dose narcotic to intrathecal baclofen in order to reduce refractory symptoms.
Methods: This is a retrospective case series of eleven patients at Buffalo General Medical Center being treated with intrathecal baclofen for neurogenic spasticity. Seven of the patients had poorly controlled spasticity-related pain. Four of the patients had refractory hypertonus. These patients subsequently underwent addition of low dose intrathecal narcotic to their ongoing baclofen therapy.
Results: When narcotic was added to the intrathecal baclofen, the baclofen dose was initially decreased by twenty percent, and then adjusted for symptom control. In the four patients with refractory hypertonus, marked reduction in tone was achieved at a lower dose of intrathecal baclofen following addition of narcotic. The seven patients with sporadic painful spasms experienced significant improvement in their pain, but no reduction in baclofen dose. The low dose narcotic was well tolerated in both groups, and did not result in any adverse effects.
Conclusions: This preliminary study suggests that addition of narcotic to intrathecal baclofen is efficacious in the treatment of refractory hypertonus and spasticity-related pain. Our findings demonstrate clinical improvement in all patients that underwent the addition of intrathecal narcotic. This clinical improvement was achieved via either reduction in tone or improvement in spasticity-related pain. Further research is required to investigate the pathophysiology behind these findings.
Patient Care: This manuscript with help create guidelines for use of dual therapy agents intrathecal treatment of pain and spasticity.
Learning Objectives: This paper focuses on the role of dual anti-anelgesc and anti-spastic intrathecal therapy.
References: 1. Coffey, J.R., et al., Intrathecal baclofen for intractable spasticity of spinal origin: results of a long-term multicenter study. J Neurosurg, 1993. 78(2): p. 226-32.
2. Penn, R.D., Intrathecal baclofen for spasticity of spinal origin: seven years of experience. J Neurosurg, 1992. 77(2): p. 236-40.
3. Akman, M.N., et al., Intrathecal baclofen: does tolerance occur? Paraplegia, 1993. 31(8): p. 516-20.
4. Wallace, M. and T.L. Yaksh, Long-term spinal analgesic delivery: a review of the preclinical and clinical literature. Reg Anesth Pain Med, 2000. 25(2): p. 117-57.
5. Vidal, J., et al., Efficacy of intrathecal morphine in the treatment of baclofen tolerance in a patient on intrathecal baclofen therapy (ITB). Spinal Cord, 2004. 42(1): p. 50-1.
6. Hara, K., et al., The interaction of antinociceptive effects of morphine and GABA receptor agonists within the rat spinal cord. Anesth Analg, 1999. 89(2): p. 422-7.