Dantrolene treatment for abrupt intrathecal baclofen withdrawal

Transient alteration of consciousness in spinal cord injury secondary to Baclofen use: a case report

INTRODUCTION

Oral baclofen is commonly used for spasticity management, especially with neurogenic bladder in spinal cord injury (SCI). A less common side effect of baclofen is transient alterations of consciousness, which can easily be confused for altered mental status secondary to orthostatic hypotension in SCI.

CASE PRESENTATION

A 43-year-old man with an acute SCI secondary to an aortic dissection was found to have episodes of confusion after titrating oral baclofen from 5 mg three times per day to 10 mg three times per day at an acute rehabilitation facility. Orthostatic hypotension was initially suspected as the cause of transient alterations of consciousness; however, he was never found to be hypotensive during these episodes. His confusion resolved several days after discontinuation of baclofen.

DISCUSSION

Although, confusion and lightheadedness in SCI are commonly caused by orthostatic hypotension, it is important for physicians to be cognizant of baclofen's side effects, which increase in the setting of acute kidney injury (AKI). If an adverse effect is suspected, baclofen should be tapered while remaining observant for signs of baclofen withdrawal, which can be life-threatening. This case report is a reminder for clinicians to be aware of the uncommon adverse effects of baclofen when initiating therapy in SCI, especially in patients with AKI and neurogenic bladders.

Baclofen therapeutics, toxicity, and withdrawal: A narrative review

Baclofen is an effective therapeutic for the treatment of spasticity related to multiple sclerosis, spinal cord injuries, and other spinal cord pathologies. It has been increasingly used off-label for the management of several disorders, including musculoskeletal pain, gastroesophageal reflux disease, and alcohol use disorder. Baclofen therapy is associated with potential complications, including life-threatening toxicity and withdrawal syndrome. These disorders require prompt recognition and a high index of suspicion. While these complications can develop following administration of either oral or intrathecal baclofen, the risk is greater with the intrathecal route. The management of baclofen toxicity is largely supportive while baclofen withdrawal syndrome is most effectively treated with re-initiation or supplementation of baclofen dosing. Administration of other pharmacologic adjuncts may be required to effectively treat associated withdrawal symptoms. This narrative review provides an overview of the historical and emerging uses of baclofen, offers practical dosing recommendations for both oral and intrathecal routes of administration, and reviews the diagnosis and management of both baclofen toxicity and withdrawal.

A Novel Approach to Avoid Baclofen Withdrawal When Faced With Infected Baclofen Pumps

BACKGROUND

Intrathecal (IT) Baclofen is beneficial for spasticity, but if pumps become infected necessitating removal, baclofen withdrawal is difficult to manage and life-threatening. Furthermore there is no consistency between dosing and severity of withdrawal. Case reports detail full baclofen withdrawal at dosages of 260 μg/day.

OBJECTIVE

To demonstrate that in patients on stable IT baclofen for prolonged periods, externalizing a patient's original IT pump is a safe, effective way to wean IT doses.

METHODS

Here, we describe a technique of continuing IT baclofen when urgent pump removal is needed. Specifically, we remove the infected pump. Then using a new or existing lumbar drain based on extent of infection, we reconnect the pump after cleaning with betadine and administer therapy externally during IT weaning.

RESULTS

Hundred forty seven baclofen pumps were implanted or replaced within four years. Infections occurred in seven patients. We utilized this technique in five of seven patients. Mean IT dose at time of explant was 400.5 ± 285.3 μg/day. We titrated the dose by 20-50% per day based on clinical response over a mean of 6.2 ± 1.3 days. The catheter was removed at bedside once weaning was complete. No patients had any signs of withdrawal, excluding minimal spasticity increases while optimizing oral treatment.

CONCLUSION

Here, we show preliminary evidence that an externalized IT pump is an effective means of weaning IT baclofen when infection of the pump occurs. This treatment strategy warrants further investigation, but appears to be a safe and effective.

CONFLICT OF INTEREST

Dr. Pilitsis is a consultant for Medtronic, Boston Scientific, Nevro, Jazz Pharmaceuticals, Neurobridge Therapeutics, and Abbott and receives grant support from Medtronic, Boston Scientific, Abbott, Nevro, Jazz Pharmaceuticals, GE Global Research and NIH 1R01CA166379. She is medical advisor for Centauri and Karuna and has stock equity. Dr. Sukul receives consultant fees from Medtronic. Julia Prusik receives grant support from Jazz Pharmaceuticals.

Dexmedetomidine for acute baclofen withdrawal

BACKGROUND

Intrathecal baclofen is widely accepted as a treatment option for severe spasticity through its γ-Aminobutyric acid-B (GABAB ) agonist properties. Abrupt cessation can lead to severe and life-threatening withdrawal characterized by altered mental status, autonomic dysreflexia, rigidity, and seizures. This symptomatic presentation is similar to alcohol withdrawal, which is mediated by modification of GABAA expression. Use of the α2-adrenergic agonist dexmedetomidine for the treatment of ethanol withdrawal has been widely reported, raising the question of its potential role in baclofen withdrawal. We present a case of the successful treatment of acute severe baclofen withdrawal with a dexmedetomidine infusion.

METHODS

A 15-year-old patient with spastic quadriparesis and cerebral palsy underwent unexpected removal of his baclofen pump due to an infection that was encountered during a planned pump revision. Following removal, he was placed on high dose enteral baclofen every 6 h. Despite further benzodiazepine supplementation, he had progressive hemodynamic instability, severe rebound spasticity, and intermittent spontaneous clonus consistent with baclofen withdrawal. A dexmedetomidine infusion was titrated to a peak dose of 16 mcg per hour with successful treatment of withdrawal symptoms.

RESULTS

The patient became normotensive without tachycardia. Tone and agitation improved.

CONCLUSION

Dexmedetomidine is to our knowledge a previously unreported option for treatment of acute severe baclofen withdrawal. We report a case of safe and efficacious use in a patient with spastic quadriparesis on chronic intrathecal baclofen. Scientifically rigorous comparison with other options remains to be performed.

Accidental intoxication with 60 mg intrathecal baclofen: survived

BACKGROUND

Intrathecal baclofen (ITB) is an effective and well-tolerated treatment for patients with severe spasticity. Intoxications are rare and usually iatrogenic, with reported intrathecal boluses varying between 0.050 and 30 mg.

METHODS

We here report the case of a 47-year-old woman with severe spastic paraplegia due to multiple sclerosis who, during a routine filling procedure, accidentally received a bolus of 60 mg ITB because of injection into the side-port instead of the reservoir of her ITB pump (Archimedes(®), Codman, Germany).

RESULTS

After a short period of dizziness, she lost consciousness and stopped breathing. She was immediately intubated, mechanically ventilated, and admitted to the intensive care unit. As specific treatment, she received cerebrospinal fluid drainage through a newly implanted lumbar catheter. A series of generalized and complex partial seizures were treated with levetiracetam and lacosamide. Acute autonomic dysfunction with episodic arterial hypo- and hypertensions was controlled by catecholamines and clonidine, respectively. Recurrent hyperthermia, however, responded neither to drugs nor to physical treatment. After 3 weeks, the patient was discharged without any relevant new neurologic signs or symptoms.

CONCLUSIONS

This case demonstrates that even excessive doses of ITB can let the patients survive without sequelae if treated promptly and offensively. A pertinent problem during detoxification is the question of when to restart ITB to avoid drug withdrawal.

Acute intrathecal baclofen withdrawal: a brief review of treatment options

BACKGROUND

Acute baclofen toxicity and withdrawal can present with a constellation of symptoms making differentiation between these two entities and other potential diagnoses challenging. Baclofen withdrawal is associated with numerous complications which may require neurocritical care expertise such as respiratory failure, refractory seizures, delirium, and blood pressure lability.

METHODS

Case report and literature review.

RESULTS

This case report discusses a case of intrathecal baclofen (ITB) withdrawal, focusing on the differential diagnosis for acute baclofen withdrawal and reviews the various options that exist to treat the symptoms of acute baclofen withdrawal such as benzodiazepines, propofol, skeletal muscle relaxants, and tizanidine.

CONCLUSIONS

Critical care practitioners should be prepared to treat this potentially devastating and often refractory complication of ITB therapy.

Intrathecal baclofen therapy: indications, pharmacology, surgical implant, and efficacy

Intrathecal baclofen (ITB) therapy is an option for those in whom predominantly lower extremity spasticity is severe, problematic, and intractable to oral doses of medications and/or focal treatment. When delivered to the lumbar area, ITB avoids high concentrations from reaching the brain (4:1 ratio lumbar to brain cisterns). A screening test dose is done prior to implanting the pump via a lumbar puncture with 50 microg baclofen, working up to 100 microg if necessary. There are two [2] types of pumps. The electronic programmable type has the advantage of flexibility of dosing and frequent change of doses for fine-tuning the patient's optimal dose. The mechanical constant flow type has the advantages of (1) being gas driven and not needing battery replacement, and (2) not needing a programmer to refill, thus allowing geographically removed patients to benefit from ITB. Catheter complications are reduced by using a shallow-angle paramedian oblique insertion to the spine, and meticulous anchoring of the catheter. Threading the catheter to T6/7 rather than the traditional T10/11 can allow upper limb relief also. Long term efficacy is excellent, although catheter complications are frequent. and if not recognized and treated, can lead to significant effects of withdrawal of baclofen.

Epidural analgesia in a patient with an intrathecal catheter and subcutaneous pump to deliver baclofen

Baclofen is used for the treatment of spasticity. Small doses administered intrathecally achieve high cerebrospinal fluid concentrations with reduced side-effects. Pediatric anesthesiologists are often reluctant to consider epidural analgesia in children receiving baclofen via an intrathecal catheter and subcutaneous pump. This reluctance is based on concerns for damaging the intrathecal catheter and introducing infection. In addition, the acute cessation of intrathecal baclofen can precipitate a life-threatening withdrawal state. We report a case of successful epidural analgesia in a patient receiving intrathecal baclofen and discuss the steps we took to minimize the chance of harm with this technique. We conclude that an intrathecal catheter and subcutaneous pump to deliver baclofen should not preclude the use of an epidural catheter for perioperative analgesia.

A benefit-risk assessment of baclofen in severe spinal spasticity

Baclofen is used for treatment of the spasticity of spinal origin that is a common sequela of spinal cord injury and multiple sclerosis; spasticity occurs in about 50% of patients affected by these disorders. In open-label studies of oral baclofen, the drug improved spasticity in 70-87% of patients; additionally, improvement in spasms was reported in 75-96% of patients. In double-blind, crossover, placebo-controlled trials, baclofen was reported to be effective, producing statistically significant improvements in spasticity. Tizanidine is the antispasticity drug that has been most widely compared with oral baclofen; studies have generally found the two drugs to have equivalent efficacy. However, tizanidine has better tolerability, in particular weakness was reported to be occur less frequently with tizanidine than with baclofen. The main adverse effects of oral baclofen include: sedation or somnolence, excessive weakness, vertigo and psychological disturbances. The incidence of adverse effects is reported to range from 10% to 75%. The majority of adverse effects are not severe; most are dose related, transient and/or reversible. The main risks of oral baclofen administration are related to withdrawal: seizures, psychic symptoms and hyperthermia can occur. These symptoms improve after the reintroduction of baclofen, usually without sequelae. When not related to withdrawal; these symptoms mainly present in patients with brain damage and in the elderly. The limited data on baclofen toxicity in patients with renal disease suggest that administration of the drug in these persons may carry an unnecessarily high risk. Intrathecal baclofen is indicated for use in patients with spasticity of spinal origin unresponsive to treatment with maximum doses of oral baclofen, tizanidine and/or dantrolene. The benefits of continuous intrathecal baclofen infusion have been demonstrated: >80% and >65% of patients have improvement in tone and spasms, respectively. The main risks of intrathecal baclofen infusion are symptoms related to overdose or withdrawal; the latter is more important because of the associated severe effects on clinical status and the possibility of death, but it is responsive to rapid treatment. Overdose primarily arises from drug test doses or human error during refill and programming of the pump, and withdrawal most commonly occurs as a result of a problem with the delivery system. Since the adverse consequences do not exceed the benefits of oral and intrathecal baclofen for patients with spinal spasticity, the benefit/risk assessment is favourable.

Intrathecal baclofen withdrawal syndrome- a life-threatening complication of baclofen pump: a case report

Background

Intrathecal baclofen pump has been used effectively with increasing frequency in patients with severe spasticity, particularly for those patients who are unresponsive to conservative pharmacotherapy or develop intolerable side effects at therapeutic doses of oral baclofen. Drowsiness, nausea, headache, muscle weakness, light-headedness and return of pretreatment spasticity can be caused by intrathecal pump delivering an incorrect dose of baclofen. Intrathecal baclofen withdrawal syndrome is a very rare, potentially life-threatening complication of baclofen pump caused by an abrupt cessation of intrathecal baclofen.

Case presentation

A 24-year-old man with a past medical history of cerebral palsy and spastic quadriparesis developed hyperthermia, disseminated intravascular coagulation, rhabdomyolysis, acute renal failure and multisystem organ failure leading to a full-blown intrathecal baclofen withdrawal syndrome. Intrathecal baclofen pump analysis revealed that it was stopped due to some programming error. He was treated effectively with supportive care, high-dose benzodiazepines and reinstitution of baclofen pump.

Conclusion

The episodes of intrathecal baclofen withdrawal syndrome are mostly caused by preventable human errors or pump malfunction. Educating patients and their caregivers about the syndrome, and regular check-up of baclofen pump may decrease the incidence of intrathecal baclofen withdrawal syndrome. Oral baclofen replacement may not be an effective method to treat or prevent intrathecal baclofen withdrawal syndrome. Management includes an early recognition of syndrome, proper intensive care management, high-dose benzodiazepines and prompt analysis of intrathecal pump with reinstitution of baclofen.