Multicenter Retrospective Study of Neurostimulation With Exit of Therapy by Explant.

INTRODUCTION: Spinal cord stimulation (SCS) devices are cost effective and improve function as well as quality of life. Despite the demonstrated benefits of SCS, some patients have the device explanted. We are interested in exploring the patient characteristics of those explanted. METHODS: This is a retrospective chart review of neurostimulation patients who underwent explantation at 18 centers across the United States within the previous five years. RESULTS: Data from 352 patients were collected and compiled. Failed Back Surgery syndrome was the most common diagnosis (38.9%; n = 136/350) and over half of the patients reported numerical rating scale (NRS) scores ≥8 prior to implant (64.3%; n = 207/322). All patients reported changes in NRS scores across time, with an initial decrease after implant followed by a pre-explant increase (F (2, 961) = 121.7, p < 0.001). The most common reason for device explant was lack or loss of efficacy (43.9%; 152/346) followed by complications (20.2%; 70/346). Eighteen percent (18%; 62/343) of patients were explanted by a different physician than the implanting one. Rechargeable devices were explanted at a median of 15 months, whereas primary cell device explants occurred at a median of 36 months (CI 01.434, 2.373; median endpoint time ratio = 2.40). DISCUSSION: Loss or lack of efficacy and complications with therapy represent the most frequent reasons for neurostimulation explantation. Of the devices that were explanted, therapy was terminated earlier when devices were rechargeable, when complications occurred, or when pain relief was not achieved or maintained. Furthermore, in nearly 20% of the cases, a different provider than the implanting physician performed device removal. CONCLUSIONS: SCS is largely a safe and efficacious strategy for treating select chronic refractory pain syndromes. Further prospective data and innovation are needed to improve patient selection, maintain SCS therapeutic efficacy and reduce the reasons that lead to device explant.

The Polyanalgesic Consensus Conference (PACC): Recommendations for Trialing of Intrathecal Drug Delivery Infusion Therapy.

INTRODUCTION: Intrathecal (IT) drug infusion is an appropriate and necessary tool in the algorithm to treat refractory cancer and noncancer pain. The decision-making steps/methodology for selecting appropriate patients for implanted targeted drug delivery systems is controversial and complicated. Therefore, a consensus on best practices for determining appropriate use of IT drug infusion may involve testing/trialing this therapy before implantation. METHODS: This current Polyanalgesic Consensus Conference (PACC) update was designed to address the deficiencies and emerging innovations since the previous PACC convened in 2012. A literature search identified publications available since the previous PACC publications in 2014, and relevant sources were contributed by the PACC members. After reviewing the literature, the panel determined the evidence levels and degrees of recommendations. The developed consensus was ranked as strong (>80%), moderate (50-79%), or weak (<49%). RESULTS: The trialing for IT drug delivery systems (IDDS) remains an area of continued controversy. The PACC recommendations for trialing are presented in 34 consensus points and cover trialing for morphine, ziconotide, and medication admixtures; starting doses and titration practices; measurements of success; trial settings and monitoring; management of systemic opioids during trialing; and the role of psychological evaluation. Finally, the PACC describes clinical scenarios in which IT trialing is required or not required. CONCLUSION: The PACC provides consensus guidance on best practices of trialing for IDDS implants. In addition, the PACC recommends that no trial may be required in certain patient populations.

A Prospective, Randomized, Single-Blinded, Head-to-Head Long-Term Outcome Study, Comparing Intrathecal (IT) Boluses With Continuous Infusion Trialing Techniques Prior to Implantation of Drug Delivery Systems (DDS) for the Treatment of Severe Intractable Chronic Nonmalignant Pain.

OBJECTIVE: The study aims to compare intrathecal (IT) boluses to continuous infusion trialing techniques prior to implantation of drug delivery systems (DDS) for the treatment of severe intractable chronic nonmalignant pain. DESIGN: This is a prospective, randomized, head-to-head long-term outcome study. MATERIALS AND METHODS: Forty patients with comparable patient demographics were randomly assigned to two cohorts. Cohort A trialed with intermittent boluses; Cohort B trialed with continuous infusion. One patient failed trial in each group. Nineteen patients were implanted in each group. Follow-up was for 36 months with intervals at 6, 12, 18, 24, 36 months. The Brief Pain Inventory was used was used for assessment. OUTCOME MEASURES: We used the Brief Pain Inventory to measure pain (worst and average), physical function (walking, normal work, and general activity), behavioral function (mood, sleep, and relations with others), IT dose, and oral opioid use. RESULTS: We observed statistically significant reduction in pain and improvement of function in both cohorts following DDS implantation throughout the observation period. The IT dose remained virtually unchanged throughout as well, with overall limited dose escalation. Oral opioid use was significantly reduced. There was no statistically significant difference in prediction of trial success or long-term outcomes between the two cohorts. CONCLUSION: Low-dose IT opioids via DDS can provide significant and long-lasting reduction in pain, and improvement in function (physical and behavioral) for patients with chronic nonmalignant pain. The two trialing techniques tested, intermittent boluses, and continuous infusion delivered intrathecally showed no clinical significance difference in terms of predicting trial success or long-term outcomes.

Prospective study of 3-year follow-up of low-dose intrathecal opioids in the management of chronic nonmalignant pain.

OBJECTIVE: Long-term follow-up with the use of low-dose opioids in intrathecal (IT) drug delivery system (DDS) for the treatment of intractable, severe chronic nonmalignant pain. DESIGN: This is a prospective, cohort long-term outcome study. Intervention. The intervention was the implantation of DDS. METHOD AND PATIENTS: A total of 61 consecutive patients (60% females, 40% males) with a mean age of 59.2 years and a mean duration of symptoms prior to implant of 6.2 years were referred for implant of DDS for severe intractable noncancer pain. After adequate patient evaluation, each underwent a trial with IT opioids. Three patients failed the trial and 58 patients were implanted. Follow-up was 36 months, with intervals at 6, 12, 18, 24, and 36 months. The Brief Pain Inventory was used for follow-up assessment criteria at baseline prior to implant as well as throughout the duration of the study. OUTCOME MEASURES: Outcome measures included self-reported pain scores (worst and average), functional improvement, and IT dose, and oral opioid consumption. RESULTS: We observed a statistically significant reduction in both worst and average pain from baseline (8.91 and 7.47 at baseline) throughout the duration of the study (4.02 and 3.41, respectively, at 36 months) (P = 0.012 and P < 0.001, respectively). We also documented a statistically significant improvement in physical and behavioral function. All subjects showed a significant reduction in the oral opioid consumption. The dose of IT opioids remained low and virtually unchanged for 36 months of follow-up: 1.4 morphine equivalent/day at 6 months and 1.48 at 36 months. Oral opioid averaged 128.9 mg of morphine equivalent/patient/day at baseline to 3.8 at 3 month and remained at the same level throughout the study. CONCLUSION: Low-dose IT opioid can provide sustained significant improvement in pain and function for long-term follow-up in chronic noncancer pain.

Effectiveness of levetiracetam in the treatment of lumbar radiculopathy: an open-label prospective cohort study.

OBJECTIVE: The purpose of this open-label study was to assess the effectiveness and tolerability of levetiracetam (LEV) in the treatment of patients with lower lumbar radiculopathy diagnosed by clinical presentation, physical examination, and electrodiagnostics. DESIGN: Open-label, forced titration, prospective cohort intent-to-treat analysis. SETTING: Major teaching hospital. PATIENTS: Participants were recruited from the university pain clinic and through referrals from the community. Subjects were eligible to participate if they (1) were older than 18 years, (2) had leg pain greater than back pain, (3) had been symptomatic for 6 months and <5 years, (3) had a baseline visual analog scale of at least 6 on the 0-10 scale, (4) had undergone lumbar spine magnetic resonance imaging within the last 12 months that showed no surgically correctable etiology for their radicular symptoms, and (5) had undergone electrodiagnostics that was positive for lumbar radiculopathy (L4, L5, or S1 nerve roots). Twenty-six patients were enrolled, and 24 (92.3%) completed the study. INTERVENTIONS: Patients initially received LEV 500 mg twice a day for 2 weeks. Dosages were then increased to 750 mg twice day for 2 weeks, and then to 1500 mg twice a day for the remainder of the study. Patients were observed for 8 weeks after reaching the maximum dose. MAIN OUTCOME MEASUREMENTS: Treatment effectiveness was assessed with the use of biweekly brief pain inventory and patient global assessment scales. Frequency and severity of adverse events were recorded. RESULTS: The mean biweekly worst and average pain scores decreased from 7.17 and 6.27 at baseline to 4.2 and 3.9, respectively, at week 12 (P < or = .001). Improvements were reported in general activity, ability to walk, mood, and relationship with people. Side effects consisted of sedation/drowsiness (46%), gastrointestinal upset (23%), headache (19%), blurred vision (15%), weakness/fatigue (11%), and dyscoordination (11%). CONCLUSIONS: This study showed that LEV might be a well-tolerated and effective treatment for lumbar radiculopathy. A large randomized placebo-controlled trial is recommended and comparative studies with alternative agents should be sought.