The Importance of Adjuvant Agents in Acute Intrathecal Baclofen Withdrawal: Case Report and Review of the Literature

摘要

Objective: Baclofen (β-p-chlorophenyl-GABA) selectively activates the GABAB subtype of γ-aminobutyric acid (GABA) receptors, a group of receptors known to provide inhibitory neurotransmission in the central nervous system. Available for over thirty years in oral form for the treatment of skeletal muscle spasticity, its availability now includes continuous intrathecal infusion via an internally implanted pump. While ideal for long-term attenuation of symptoms, this treatment modality can also become disastrous should the pump empty and withdrawal subsequently ensue. Case Report: A 48-year-old male with a past medical history of T8 spinal cord injury from a motor vehicle crash originally presented with altered mental status. Because of resultant paraplegia and spasticity from his injuries, a neurosurgeon implanted an intrathecal baclofen pump three years prior to presentation with symptomatic relief. Further exploration revealed that he had missed his scheduled pump refill appointment and interrogation of his pump confirmed a completely empty reservoir. The patient endured a protracted hospital course that included rhabdomyolysis, acute renal failure, lactic acidosis, respiratory failure, and systemic inflammatory response syndrome. Treatment included benzodiazepines, dantrolene, aggressive hydration, opiates, and refill of his intrathecal baclofen pump. His mentation and ventilatory status improved with recovery from his critical illness and eventual discharge. Conclusions: Treatment of intrathecal baclofen withdrawal should focus on restoration of previous intrathecal baclofen levels by refill of the intrathecal pump. Adjuvant medications such as benzodiazepines, propofol, cyproheptadine, dantrolene, tizanidine, and opiates may prove crucial in helping with muscle spasticity while these levels are reestablished. A high index of suspicion, leading to timely initiation of proper treatment, may serve as the most important factor in successful recovery from this life-threatening syndrome.