Is Response to a Pre-implant Diagnostic Peripheral Nerve Block Associated With Efficacy After Peripheral Nerve Stimulation Implantation? A Ten-Year Enterprise-Wide Analysis.

OBJECTIVES: This study aimed to assess whether patient response to targeted diagnostic peripheral nerve block before peripheral nerve stimulator (PNS) device implantation is associated with efficacy after PNS implantation. MATERIALS AND METHODS: The electronic medical records from the Mayo Clinic Enterprise (three quarternary care medical centers and additional satellite medical centers) were reviewed to identify patients who underwent PNS implantation between January 2014 and January 2023. A primary outcome of interest was to assess whether administration of a preimplant diagnostic peripheral nerve block predicted pain relief at three months and six months after temporary and permanent PNS implantation. Another primary outcome was to investigate whether there was an association between the pain relief from a preimplant diagnostic peripheral nerve block and pain relief after three and six months after temporary or permanent PNS therapy. Linear regression analysis was conducted for outcomes of interest. RESULTS: Of 193 eligible patients who underwent PNS therapy, a total of 173 patients were included in the final analysis and were stratified into either the temporary PNS cohort (n = 112) or the permanent PNS cohort (n = 61). Overall, 77.5% of all patients (134/173) underwent a preimplant diagnostic peripheral nerve block and reported a mean percentage relief of 70.1 ± 27.0 from the diagnostic block. Of patients in the temporary PNS cohort, there was no difference in postimplant percentage pain relief between patients who received a diagnostic block (n = 93) and control patients (n = 19) at three months (35.4 ± 36.0 vs 49.8 ± 36.1, respectively; ß -14.45, 95% CI -32.98 to 4.07, p = 0.125) or at six months (23.3 ± 30.8 vs 45.7 ± 40.0, respectively; ß -22.39, 95% CI -46.86 to 2.08, p = 0.072). Of patients in the permanent PNS cohort, there was no difference in postimplant percentage pain relief between patients who received a diagnostic block (n = 41) and control patients (n = 20) at three months (42.4 ± 34.3 vs 43.2 ± 42.4, respectively; ß -0.79, 95% CI -23.56 to 21.99, p = 0.945) or at six months (44.3 ± 35.0 vs 38.8 ± 40.9, respectively; ß 5.42, 95% CI -20.04 to 30.88, p = 0.669). Pain relief from preimplant diagnostic blocks was associated with postimplant pain relief from temporary PNS at three months (ß 0.33, 95% CI 0.04-0.61, p = 0.025). However, pain relief from preimplant diagnostic blocks did not predict postimplant pain relief from temporary PNS at six months, or permanent PNS at three months and six months. CONCLUSIONS: Administration of a diagnostic block is not associated with superior pain relief at three or six months after PNS implantation to that of an approach without diagnostic block. Pain relief from a diagnostic block may potentially predict short-term pain relief after temporary PNS therapy, although future prospective studies are warranted to evaluate the prognostic utility of diagnostic blocks.

Incidence of Temporary Peripheral Nerve Stimulator Lead Tip Retention: A Retrospective Review of 80 Lead Placements.

OBJECTIVES: The primary objective of this study was to determine the current rate of lead fracture during temporary percutaneous peripheral nerve stimulator (PNS) lead removal at the Mayo Clinic Rochester Division of Pain Medicine. MATERIALS AND METHODS: A retrospective review of electronic medical records was performed for patients implanted with a temporary percutaneous PNS device between January 1, 2018, and December 31, 2020. Patients were included if they underwent temporary percutaneous PNS system implant, with planned lead removal at 60 days. Data collection included date of implant, diagnosis, peripheral nerve target(s), number of leads, and lead tip status at the time of removal (intact vs fractured). RESULTS: Fifty patients underwent a total of 80 temporary percutaneous PNS leads placed during the time frame analyzed. Of the 80 temporary percutaneous PNS leads implanted, there were five lead fractures at the time of intentional lead removal. CONCLUSIONS: This retrospective review of 50 patients with 80 temporary percutaneous PNS leads implanted for chronic peripheral neuropathic pain resulted in a 6.25% rate of retained lead fragment at the time of lead removal by the provider at the end of 60-day treatment. This fracture and retention rate is consistent with previous published retrospective data on PNS, which has shown a 3% to 21% lead fracture rate during intentional lead removal.

Speaker Gender Representation at the North American Neuromodulation Society Annual Meeting (2017-2021): Have We Made Progress in Closing the Gender Gap?

Background: Speaker gender representation at medical conferences is a significant site of gender disparity. Our primary objective was to quantify the proportion of female speakers and compare plenary session opportunities by gender at the North American Neuromodulation Society (NANS) Annual Conference. Methods: Data from the 2017-2021 NANS Annual Conference presentations were abstracted. Primary outcomes included gender composition of speaker slots, gender composition of individual speakers, and comparison of plenary speaker slots by gender. Secondary outcomes included comparisons of session size, age, professional degree, and number of presentations per speaker based on gender. Results: Gender composition of annual speaker slots was (% slots presented by women): 2017:14.6%; 2018:20.5%; 2019:23.5%; 2020:21.0%; 2021:41.4%. Annual gender composition of individual speakers was (% women): 2017:18.7%; 2018:20.6%; 2019:24.6%; 2020:24.9%; 2021:33.8%. Of all speaker slots, the percentage of plenary slots did not differ based on gender, with 11.4% presented by female speakers versus 11.2% presented by male speakers (OR 1.0, 95% CI 0.7-1.5, P=0.893). Compared to male speaker slots, there was an association of lower age (43.9±5.6 vs 50.8±8.9, P<0.001), lower odds of holding a single doctorate degree (OR 0.3, 95% CI 0.2-0.5, P<0.001), and lower odds of holding a dual MD/PhD or DO/PhD degree (OR 0.3, 95% CI 0.1-0.5, P<0.001) in female speaker slots. Compared to male speakers, there was an association of higher number of presentations per female speaker at the 2021 NANS Annual Meeting (2.48±1.60 vs 1.79±1.30, P=0.008). Conclusion: Although the volume of female speaker slots and individual speakers trailed behind their male counterparts, female speaker representation steadily increased at each subsequent annual NANS meeting. We identified no difference in plenary session slots based on gender.

An Advanced Practice Provider Guide to Peripheral Nerve Stimulation.

Objective: To describe the team approach of an interventional pain management practice, with particular emphasis on advanced practice providers (APPs), in the selection, education, care, and management of peripheral nerve stimulation (PNS) patients. Materials and Methods: We devised an APP guide to PNS based on an in-depth search of multiple databases for studies on neuromodulation, pain management, and APPs. Results: Of 65 articles captured in the search strategy, three articles were pertinent to the topic of APP involvement in neuromodulation. More specifically, only one of the three publications on neuromodulation discussed APP involvement in PNS. This single publication was from 1995 and focused on electrical stimulation of the trigeminal ganglion using a permanent percutaneously placed electrode. Conclusion: PNS is growing in clinical indication and use for both acute and chronic pain conditions. With the increasing need for APPs in both general and specialty medicine, it is imperative that APPs are well educated on PNS. Here, we have outlined ways in which APPs can optimize the care of PNS patients and how the skillset of the APP in a PNS practice can potentially improve patient outcomes.