Correlation between Withdrawal Symptoms and Medication Pump Residual Volume in Patients with Implantable SynchroMed Pumps

Interaction between a smartphone and intrathecal baclofen pump case report

INTRODUCTION

Intrathecal Baclofen (ITB) is used for the treatment of spasticity. Pump complications are most commonly related to surgical implantation or catheter dysfunction. Less common complications include catheter access port dysfunction, motor failure from excessive wear on motor gear shafts, or a complete stall of the motor.

CASE PRESENTATION

37-year-old with T9 motor complete paraplegia with ITB presented in baclofen withdrawal. Workup revealed that the pump's motor was not turning, requiring pump replacement. Questioning revealed that he had not undergone any MRI studies within the past six months, but that he recently purchased a new iPhone. The phone was 2-3 inches away from the pump for up to twelve hours a day, carried in a fanny pack around his waist.

DISCUSSION

We present a case of motor pump failure from long term exposure to a magnetic field from a new iPhone. The ability of iPhones to overpower an ITB pump magnet is not widely known. In 2021, the Food and Drug Administration published a report regarding the effects of magnets in consumer electronics on implanted medical devices, recommending that such electronics should be kept at least 6 inches from the device. Providers should be aware of the ability of new models of commonly used electronic devices to stall the ITB motor to avoid life-threatening complications of baclofen withdrawal.

Potential for Intrathecal Baclofen in Treatment of Essential Tremor

INTRODUCTION

Essential tremor (ET) is the most common movement disorder of adults, affecting an estimated 7 million Americans. Symptoms of ET range from slightly noticeable to debilitating, with 1 cohort study finding 15% of patients were forced into early retirement. Additionally, depression has also been correlated with the severity of disability of ET. Treatment options include propranolol and primidone. Current treatment options are not very effective, with more than half (56.3%) of patients discontinuing medications because of no changes in symptoms.

METHODS

Unfortunately, there is a relative void and controversy in the literature explaining ET pathophysiology; however, the gamma-aminobutyric acid (GABA) hypothesis is the strongest. We conducted a PubMed search on 30 September 2015 with no time constraints using the search terms "essential tremor" and "baclofen," which resulted in a total of 5 articles.

RESULTS

Neurohistopathologic studies have demonstrated decreased GABA-A and GABA-B receptors in the cerebellar cortex of ET patients. GABA, the major inhibitory neurotransmitter in the central nervous system, is proposed to have an inhibitory effect on pacemaker output activity of the cerebello-thalamo-cortical pathway, with lower receptors resulting in decreased inhibition of baseline tremors. Tariq et al showed delayed onset and intensity of tremor with oral administration of R-baclofen in a mouse model of ET.

CONCLUSION

With a better side-effect profile and success in a physiologically related condition, we propose more clinical trials and research be carried out on intrathecal baclofen as a potential treatment option, especially drug refractory ET, so as to increase the quality of life of this patient population.

Continuous intrathecal baclofen for children with spasticity and/or dystonia: Goal attainment and complications associated with treatment

AIM

To describe complications and outcomes of intrathecal baclofen (ITB) therapy in children with spasticity and/or dystonia.

METHODS

A prospective study of goal attainment after ITB therapy and a retrospective review of medical records for complications. The children were described as dystonia-predominant or spasticity-predominant and the subgroups were compared. Goals were assessed at baseline and goal attainment at 6 months post-implant. Data were analysed using Wilcoxon signed-rank test. The patients' goals were measured with the Canadian Occupational Performance Measure (COPM) and goal attainment scaling (GAS). Complication rates were calculated by dividing the number of complications by the duration of pump implantation.

RESULTS

Twenty-five children were included, 16 with complete goal attainment data. The mean age was 10 years and 3 months. Eighty-eight percent had a diagnosis of cerebral palsy. The most common goals were improved positioning and transfers. A statistically significant increase (P < 0.001) in both domains of the COPM was demonstrated. The mean GAS T-score was significantly higher at 6 months post implant (P < 0.001). Seventy percent of the subjects achieved their goals at 6 months. The complication rate was 0.38 per year of pump operation, higher in subjects with dystonia (0.71) compared with those with spasticity (0.25).

CONCLUSIONS

ITB results in statistically significant levels of satisfaction and goal attainment in children with spasticity and/or dystonia. GAS was a useful measure of goal attainment. While, ITB is effective for children with spasticity and dystonia, those with dystonia have a higher rate of complications.

Intrathecal drug therapy for long-term pain management

PURPOSE

The use, safety, and efficacy of intrathecal medication administration with implantable pumps for cancer and chronic pain management are reviewed.

SUMMARY

Implanted intrathecal drug-delivery systems (IDDSs) are used for long-term management of persistent, severe pain despite a multimodal approach with conventional pain treatment options. Currently, consensus papers published in the literature are used as guidelines for determining patient selection and medication administration, because there is a lack of supporting evidence from randomized, controlled, clinical trials. Pharmacists have a critical role in the safe use of intrathecal medication. Most of the medication concentrations and combinations administered through IDDSs are not commercially available and therefore must be compounded in a pharmacy. Medications commonly administered through IDDSs include opioids, local anesthetics, clonidine, baclofen, and ziconotide. It is important for pharmacists who prepare products for IDDSs to understand the pharmacology, adverse effects, and concentration limitations of each medication in order to prevent adverse events related to postoperative subarachnoid hemorrhage, infection, catheter-tip inflammatory masses, withdrawal, and overdose. Pharmacists play an important role in maintaining quality assurance of intrathecal drug use, including the use of standard procedures for ordering and compounding medications, documentation of patient education, and monitoring of patient outcomes.

CONCLUSION

The use of long-term intrathecal drug delivery for the treatment of intractable pain or intolerable medication adverse effects has expanded to include the treatment of patients with chronic or cancer-related pain. Important considerations for the use of intrathecal drug therapy include the appropriate selection of patients, delivery systems, and medications, as well as potential complications of therapy and quality-assurance measures necessary to ensure patient safety.

Programmable intrathecal opioid delivery systems for chronic noncancer pain: a systematic review of effectiveness and complications

OBJECTIVES

We conducted a systematic review of the literature on the effectiveness and complications of programmable intrathecal opioid and ziconotide drug delivery systems (IDDS) for patients with chronic noncancer pain.

METHODS

We searched MEDLINE, Cochrane, and other bibliographic databases to identify English-language journal articles reporting programmable IDDS complications or effects on pain or functioning. Additional study methodology criteria were applied for the effectiveness review. Two authors independently abstracted data from each included article.

RESULTS

Six articles met the inclusion criteria for the effectiveness and complications reviews, and 4 others met the criteria only for the complications review; none were randomized trials or of ziconotide. All 6 articles reviewed for effectiveness reported improvement in pain and functioning on average among patients who received a permanent IDDS. Two articles reported the proportion of patients with > or =50% improvement in pain at 6 months (38%, 56%) and 2 at longer follow-ups (30%, 44%). Intrathecal morphine-equivalent doses increased over time. The most commonly reported permanent IDDS drug side effects were nausea/vomiting (mean rate weighted by sample size=33%), urinary retention (24%), and pruritus (26%). Catheter problems were also reported commonly. Rare but serious complications included intrathecal catheter tip granulomas.

CONCLUSIONS

The studies reviewed found improvement in pain and functioning on average among patients with chronic noncancer pain who received permanent IDDS. However, their methodologic limitations preclude conclusions concerning the effectiveness of this technology long-term and as compared with other treatments. Drug side effects and hardware complications were common. Suggestions are made for methodologic improvements in future studies.

Intrathecal baclofen in the treatment of spasticity

Spasticity is a disorder of the sensorimotor system resulting in velocity-dependent increased muscle tone and tendon reflexes. Intrathecal baclofen is currently the most effective means of treating diffuse abnormal spasticity of both cerebral and spinal origin in the adult and pediatric patient. Careful patient assessment, selection and continued therapies are essential to a successful intrathecal baclofen management program. Once a patient receives a baclofen pump, close monitoring is needed for dose adjustment and pump problems. Baclofen overdose and withdrawal by either system failure or human error can cause significant side effects and be life threatening. Excellent understanding of the baclofen delivery system, programming and dose effects are needed to evaluate any patient complaints. Future uses of intrathecal pump therapy includes use of other intrathecal drugs besides baclofen (or in combination with baclofen) and the effects of placing the catheter tip at various spinal levels. At the University of Minnesota, Sister Kenny Institute and Gillette Children's Specialty Healthcare our experience has shown excellent results with this form of therapy over the last 12-16 years.

Management of spasticity in multiple sclerosis by intrathecal baclofen

Since its introduction, chronic intrathecal baclofen (ITB) infusion has been proved to improve spasticity, spasms and related pain. In the literature, the reported clinical improvement is evident in more than 85% of the patients suffering from spasticity and in more than 66% of the patients suffering from spasms. Usually, the evaluation of spasticity is carried out by the Asworth Scale although there is not yet general accordance on the validity of this scale. It is possible that some of the scales used to assess the implanted patients are not sensitive enough to detect changes in the quality of life or functional outcome. After the pump's implantation, the overall care seems to be rather simple for a devoted team. The side effects are usually temporary but they can worry the patients. The most dangerous side effects are baclofen overdose and withdrawal syndrome. These complications are totally avoidable by adopting an approach attentive to the details regarding the patient, the device, and the procedure.