Intraoperative neurophysiological monitoring and spinal cord stimulator implantation.

INTRODUCTION: Spinal cord injury (SCI) is one of the most dreaded complications after spinal cord stimulation (SCS) implantation surgery. As a result, intraoperative neurophysiological monitoring (IONM) has been proposed to avoid accidental damage to nervous structures under anesthesia and confirm positioning for optimal stimulation. Our study uses a large administrative claims database to determine the 30-day risk of SCI after SCS implantation. METHODS: This retrospective cohort study used the IBM MarketScan Commercial and Medicare Supplemental Databases from 2016 to 2019. Adult patients undergoing SCS surgical procedures with at least 90 days of follow-up, IONM use, the type of sedation used during the procedure, and subsequent SCI were identified using administrative codes. In addition, logistic regression was used to examine the relationship between various risk factors and subsequent SCI. RESULTS: A total of 9676 patients underwent SCS surgery (64.7% percutaneous implants) during the study period. Nine hundred and forty-four (9.75%) patients underwent SCS implantation with IONM. Conscious sedation, Monitored Anesthesia Care anesthesia, and general anesthesia were used in patients with 0.9%, 60.2%, and 28.6%, respectively. Eighty-one (0.8%) patients developed SCI within 30 days after SCS implant surgery. The SCI rate was higher in the group that underwent IONM (2% vs 0.7%, p value <0.001) during the implantation procedure, reflecting the underlying risk. After adjustment for other factors, the OR of SCI is 2.39 (95% CI: 1.33 to 4.14, p value=0.002) times higher for those with IONM than those without IONM. CONCLUSIONS: Increased SCI risk among patients with IONM likely reflects higher baseline risk, and further research is needed for risk mitigation.

Neck Pain Secondary to Post Radiation Fibrosis Managed With Ultrasound-Guided Adhesiolysis.

BACKGROUND: Radiation therapy may result in complications, including fibrosis, which can result in pain and difficulty with movement - especially in the neck. CASE PRESENTATION: A 52-year-old man with right-sided vague neck pain unresponsive to conservative management had a computed tomography scan that showed a vagal paraganglioma in the carotid sheath surrounding the right carotid arteries and internal jugular vein. Following radiation therapy, he noticed a new pain in his right jaw and neck worse with certain movements of the neck. Nonsurgical conservative measures including physical therapy and pharmacological management were unsuccessful. An ultrasound evaluation demonstrated fibrosis beneath the sternocleidomastoid muscle and in proximity to the carotid sheath. After careful trajectory planning using ultrasound imaging, a 25 G needle was introduced real time in proximity to the fibrosis. Using a dexamethasone/saline mixture under real-time ultrasound guidance, adhesions were released. After 3 injections, the patient reported greater than 90% pain relief, which lasted 4 months. Subsequently, he required similar injections approximately every 3 months to achieve greater than 75% pain relief. CONCLUSIONS: This is a successful demonstration of the utility of ultrasound evaluation and guidance for adhesiolysis following radiation therapy.

Lead and Pulse Generator Migration After Spinal Cord Stimulation Implantation: Insights From an Analysis of 7322 Patients.

OBJECTIVES: Lead migration (LM) after spinal cord stimulation (SCS) implantation surgery is the most common device-related complication. Our study of lead and implantable pulse generator (IPG) migration using a large administrative claims data base aims to understand rates, risk factors, and outcomes after SCS implantation. MATERIALS AND METHODS: This retrospective cohort study used the IBM® MarketScan® (Armonk, NY) Commercial and Medicare Supplemental Databases from 2016 to 2018. Adult patients who underwent SCS surgical procedures with at least 90 days of follow-up were identified using Current Procedural Terminology (CPT®) codes. Patients with LM and IPG migration after SCS surgery were identified using the International Classification of Diseases, 10th Revision, Clinical Modification (ICD-10 CM) codes. Patients who underwent revision surgery after SCS implantation were identified using the CPT codes and ICD-10 CM codes. In addition, patient characteristics associated with LM or IPG migration, the temporal relationship of migration diagnosis, and revision surgery were evaluated in the cohort. Continuous outcomes were compared between groups using the two-sample Student t-test. The Fisher exact test was used to compare categorical outcomes between groups. RESULTS: A total of 7322 patients (64.4% percutaneous SCS) underwent SCS surgery during the study period. A total of 141 patients (1.9%) had LM or IPG migration. Of those, 116 patients (1.6%) had LM only; 18 patients (0.2%) had IPG migration; and seven patients (0.1%) had LM and IPG migration. The mean duration for migration diagnosis after initial SCS implantation was 168 (±163.1) days. The mean duration to revision surgery after the migration diagnosis was 12.3 (±35.2) days only. Most patients with migration (105, 74.5%) underwent revision surgery. Only younger age (p = 0.02) was associated with migration in this study. CONCLUSIONS: LM and pulse generator migration that required revision surgery occurred in a small proportion of patients who underwent SCS surgical procedures.

Postoperative Oral Antibiotic Use and Infection-Related Complications After Spinal Cord Stimulator Surgery.

OBJECTIVES: Spinal cord stimulation (SCS) is considered a minimally invasive and reversible neuromodulation therapy for various chronic pain disorders. The rates of infection following SCS surgery reported in the literature range from 2.8% to 10%. Several studies indicated no potential benefit of postoperative antibiotics (beyond 24 hours) on subsequent device infection. This study aimed to understand the characteristics of postoperative antibiotic prescriptions and subsequent infections following SCS surgery. MATERIALS AND METHODS: The study was a retrospective cohort using the IBM® MarketScan® Commercial and Medicare Supplemental Databases from 2013 to 2018. Adult patients undergoing SCS surgical procedures with at least 90 days of follow-up were identified using Current Procedural Terminology (CPT®) codes. Postprocedural oral antibiotics within 14 days and preprocedural corticosteroid use within seven days were identified using National Drug Codes (NDC). Administrative claims were analyzed to understand the characteristics of prescribed postoperative antibiotics. Infection-related complications within 90 days were identified using administrative codes. RESULTS: A total of 18,105 patients (age 55.5 ± 13.1 years, 40.2% male) underwent SCS surgery during the study period. Postprocedural oral antibiotics and preprocedural steroids were prescribed for 35.3% and 2.6%, respectively, for SCS surgery patients. The most commonly used postprocedural antibiotics were cephalexin (55.4%) and sulfamethoxazole-trimethoprim (10.6%). The most common duration of antibiotic prescriptions was seven, ten, and five days in our study, from most to least common duration. Superficial surgical site infection (SSI), deep SSI, device infection, or any infection within 90 days occurred in 2.9%, 1.0%, 1.8%, and 4%, respectively, of the patients undergoing SCS surgery. CONCLUSIONS: Prospective studies are needed to understand the reasons for noncompliance with expert consensus recommendations on postoperative antibiotic use beyond 24 hours of SCS surgery. Neuromodulation team members should play an important role in antibiotic stewardship.

Procedure-Related Outcomes Including Readmission Following Spinal Cord Stimulator Implant Procedures: A Retrospective Cohort Study.

BACKGROUND: Spinal cord stimulation (SCS) has been shown to reduce opioid consumption, reduce pain, improve quality of life compared to conventional therapy, and be more effective than spine reoperation in carefully selected patients. In this study, we evaluate readmissions after SCS implantation procedures, costs, predictors, and etiologies for readmission following implantation procedures. METHODS: The study was a retrospective cohort using the National Readmissions Database from 2013 to 2017. Administrative billing codes were used to identify patients undergoing SCS implantation procedures. The primary outcome of our study was 30-day readmission following the SCS implantation procedure. Continuous outcomes were compared between groups using the Student t test or Wilcoxon rank sum test. In addition, multivariable predictors of 30-day readmission were assessed by hierarchical logistic regression analysis. RESULTS: A total of 3737 (26.7% open surgical SCS implants [OS-SCS]) individuals admitted to the hospital for SCS implantation were included in the final cohort analysis. The cohort consisted of predominantly female patients (58.71%) and in the 50- to 64-year age group (35.46%). Patients who underwent open surgical SCS implantation had a longer length of stay during the initial admission and a higher 30-day readmission rate (9.4% vs 7% P = .01). OS-SCS, older age, lower socioeconomic status, patients with specific comorbidities (ie, hypertension or chronic obstructive pulmonary disease [COPD]), and home discharge are associated with readmission. CONCLUSIONS: Readmission rates after SCS implantation are around 7.7% in the United States. Infection and postoperative complications remain the top etiologies for readmission. Open surgical SCS implantation is associated with more extended initial hospitalization and a higher rate of readmission when compared to percutaneous SCS implantation procedures.

Industry Payments to Pain Medicine Physicians: An Analysis of the Centers for Medicare and Medicaid Services Open Payments Program.

OBJECTIVE: To analyze industry payments to pain medicine physicians in the United States. DESIGN: Retrospective cohort study using publicly available databases. SUBJECTS: The study includes U.S. pain medicine physicians (PMPs) with reports in the Open Payments program from 2013 to 2018. METHODS: The Centers for Medicare and Medicaid Services Open Payments program was analyzed for general, investment, and ownership payments to PMPs reported from 2013 to 2018. The nature, type, and geographic variation of payments were analyzed. RESULTS: The main findings of the study are as follows: 1) Payments made to PMPs constituted a small proportion of the payments made to all physicians in the United States, and the number of transactions and the total dollar amount seem to have decreased from 2016 to 2018. 2) The median number of payments among physicians with reported payments was around 4 (interquartile range: 18), and the majority of them were under $20. 3) The majority of payments were for in-kind items and services (85%) and were made for food and beverages (91%), travel and lodging (5.5%). 4) Some of the ownership and investment interest payments exceeded $500,000. 5) The top five drugs associated with physician payments included medications with opioids. 6) A very small minority of payments were made for entertainment or gifts. 7) A third of PMPs with reports had payments reported under more than one taxonomy. CONCLUSIONS: Overall payments made to PMPs seem to be decreasing since 2016. The majority of the payments are made for the food, beverage, and travel categories. Public and physician awareness of the Open Payments system reports is essential to promote transparency and to minimize adverse effects of financial relationships on patient care.

American Society of Regional Anesthesia and Pain Medicine expert panel recommendations on point-of-care ultrasound education and training for regional anesthesiologists and pain physicians-part II: recommendations.

Point-of-care ultrasound (POCUS) is a critical skill for all regional anesthesiologists and pain physicians to help diagnose relevant complications related to routine practice and guide perioperative management. In an effort to inform the regional anesthesia and pain community as well as address a need for structured education and training, the American Society of Regional Anesthesia and Pain Medicine Society (ASRA) commissioned this narrative review to provide recommendations for POCUS. The recommendations were written by content and educational experts and were approved by the guidelines committee and the Board of Directors of the ASRA. In part II of this two-part series, learning goals and objectives were identified and outlined for achieving competency in the use of POCUS, specifically, airway ultrasound, lung ultrasound, gastric ultrasound, the focus assessment with sonography for trauma exam, and focused cardiac ultrasound, in the perioperative and chronic pain setting. It also discusses barriers to POCUS education and training and proposes a list of educational resources. For each POCUS section, learning goals and specific skills were presented in the Indication, Acquisition, Interpretation, and Medical decision-making framework.

American Society of Regional Anesthesia and Pain Medicine expert panel recommendations on point-of-care ultrasound education and training for regional anesthesiologists and pain physicians-part I: clinical indications.

Point-of-care ultrasound (POCUS) is a critical skill for all regional anesthesiologists and pain physicians to help diagnose relevant complications related to routine practice and guide perioperative management. In an effort to inform the regional anesthesia and pain community as well as address a need for structured education and training, the American Society of Regional Anesthesia and Pain Medicine (ASRA) commissioned this narrative review to provide recommendations for POCUS. The guidelines were written by content and educational experts and approved by the Guidelines Committee and the Board of Directors of the ASRA. In part I of this two-part series, clinical indications for POCUS in the perioperative and chronic pain setting are described. The clinical review addresses airway ultrasound, lung ultrasound, gastric ultrasound, the focus assessment with sonography for trauma examination and focused cardiac ultrasound for the regional anesthesiologist and pain physician. It also provides foundational knowledge regarding ultrasound physics, discusses the impact of handheld devices and finally, offers insight into the role of POCUS in the pediatric population.

Opioid Prescriptions by Pain Medicine Physicians in the Medicare Part D Program: A Cross-Sectional Study.

BACKGROUND: Pain medicine physicians (PMP) are a group of physicians with background training in various primary specialties with interest and expertise in managing chronic pain disorders. Our objective is to analyze prescription drug (PD) claims from the Medicare Part D program associated with PMP to gain insights into patterns, associated costs, and potential cost savings areas. METHODS: The primary data source for Part D claims data is the Centers for Medicare and Medicaid Services (CMS) Chronic Conditions Data Warehouse, which contains Medicare Part D prescription drug events (PDE) records received through the claims submission cutoff date. Only providers with taxonomies of pain management (PM) and interventional pain management (IPM) were included in the study. The analysis of PDE was restricted to drugs with >250 claims. The distribution of claims and costs were analyzed based on drug class and provider specialty. Subsequently, we explored claims and expenses for opioid drug prescriptions in detail. Prescribing characteristics of the top 5% of providers by costs and claims were examined to gain additional insights. The costs and claims were explored for the top 10 drugs prescribed by PMP in 2017. RESULTS: There were a total of unique 3280 PMP-prescribed drugs with an associated expense of 652 million dollars in the 2017 Medicare Part D program. Prescriptions related to PMP account for a tiny fraction of the program's drug expenditure (0.4%). Opioids, anticonvulsants, and gabapentinoids were associated with the largest number of claims and the largest expenses within this fraction. Among opioid drug prescriptions, brand-named drugs account for a small fraction of claims (8%) compared to generic drugs. However, the expenses associated with brand name drugs were higher than generic drugs. Prescribers in the top 5% by PD costs had a higher number of claims, prescribed a higher proportion of branded medications, and had prescriptions associated with longer day supply compared to an average PMP. There were several opioid medications in the top 10 PD list by cost associated with PMP. CONCLUSIONS: Opioids were the most common medications among Medicare part D claims prescribed by PMP. Only 12% of the total opioid PD claims were by PMP. The top 5% of PMP prescribers had 10 times more claims than the average PMP.

Outcomes Associated With Infection of Chronic Pain Spinal Implantable Electronic Devices: Insights From a Nationwide Inpatient Sample Study.

OBJECTIVES: Chronic pain spinal implantable electronic devices (CPSIEDs) include devices that provide spinal cord stimulation and intrathecal drug therapy. In this study, we sought to evaluate the trends of CPSIED infections, related complications, and outcomes following the treatment of infection. MATERIALS AND METHODS: The Nationwide Inpatient Sample database contains data from 48 states, and the District of Columbia was used to identify patients with a primary diagnosis of CPSIED infection during the years 2005-2014. Patients with intrathecal pumps for the treatment of spasticity were excluded to limit the study population to patients with chronic pain disorders. Treatments were categorized as: 1) without device removal, 2) pulse generator or pump only removal, 3) intrathecal pump system removal, and 4) spinal cord stimulation system removal. Complications associated with CPSIED infections were identified using administrative billing codes. RESULTS: During the study period 2005-2014, a total of 11,041 patients were admitted to the hospital with CPSIED infections. The majority of the patients were treated without surgical intervention (56%), and a smaller proportion underwent complete system explantation (22.7%). In-hospital mortality or permanent disability due to paralysis after CPSIED infection was around 1.83% and 2.77%, respectively. Infectious complications such as meningitis, abscess formation, and osteomyelitis occurred in 4.93%, 5.08%, and 1.5%, respectively. The median cost of hospitalization was around US $14,118.00, and the median length of stay was approximately six days (interquartile range = 4-13 days). CONCLUSIONS: The complications of CPSIED infection were higher among patients that did not undergo device removal.

Adverse Events and Complications Associated With Intrathecal Drug Delivery Systems: Insights From the Manufacturer and User Facility Device Experience (MAUDE) Database.

BACKGROUND: Modern intrathecal drug delivery systems (IDDS) are technologically advanced to deliver medication through various automated and patient-controlled programs. They also are associated with unique complications ranging from post-operative complications, medication-related adverse events (AE), device malfunction, to refill associated AE. OBJECTIVES: To systematically analyze real-world complications and AE reported on the Food and Drug Administration's Manufacturer and User Facility Device Experience database (MAUDE) associated with IDDS among patients predominantly with chronic pain disorders. MATERIALS AND METHODS: MAUDE database was sampled for a month four times a year during the study period, February 2018 to February 2019. The database was resampled every six months till August 2020 to evaluate for any additional reported cases during the index months. The two FDA approved IDDS, were included. AE were broadly classified into causes related to catheter malfunction, pump malfunction, biologic, and medication-related AE. RESULTS: A total of 1001 reports were included in the final analysis. The top three reasons for adverse report are infection/erosion (15.7%, n = 157), motor stall (12.4%, n = 125) and adverse medication reactions (11.8%, n = 119), respectively. There were five deaths among patients with IDDS. Epidural hematoma (n = 3) after IDDS surgery resulted in a death and residual neurological deficits after surgical evacuation. Programming errors, medication concentration discrepancy, and failure to turn on the pump after reprogramming are various preventable causes of medication-related IDDS AEs. CONCLUSIONS: Analysis of AE associated with IDDS from the MAUDE database provided a real-world perspective different from reported registry complications. Awareness and vigilance of preventable IDDS-related complications is the first step toward mitigating risks to provide safe and effective intrathecal drug delivery for chronic pain management.

Inappropriate Defibrillator Shocks During Cervical Medial Branch Radiofrequency Ablation: A Case Report.

A 52-year-old woman with a history of cervical spondylosis, nonischemic dilated cardiomyopathy, and complete heart block with implantation of a cardiac resynchronization therapy defibrillator (Inogen XR, Boston Scientific, Natick, MA) underwent bilateral fluoroscopy-guided radiofrequency ablation of the medial branch nerves at C4, C5, and C6 levels at an ambulatory surgery center. After completion of the seemingly routine procedure, several alerts, including 1 inappropriate shock, were received via Boston Scientific's remote monitoring system. Tracings also showed that pacing inhibition occurred. When performing radiofrequency ablation in patients with a cardiac implantable electronic device, it is imperative to follow published best practice recommendations to minimize the risk of adverse events.

Indented intrathecal drug delivery system with loss of reservoir volume.

OBJECTIVES: We report two patients who underwent elective revision surgery were found to have reduced reservoir volumes and indented bottom shield of intrathecal drug delivery system (IDDS). CASE REPORTS: Case #1: A 59-year-old man stable on IDDS medications for chronic neck and upper back pain was found to have an irreversible reduction in reservoir volume from 40 to 28 cc on routine refill appointment. Despite having stable pain control, the reservoir volume decreased from 40 to 22 cc and subsequently to 17 cc when the patient had inadequate pain control. During replacement surgery, the posterior shield of the IDDS was found to be collapsed. The patient had exposure to hyperbaric oxygen treatments for chronic non-healing wounds of the lower extremities. Case #2: A 68-year-old woman had an IDDS implanted for chronic low back pain secondary to failed back surgery syndrome. The reservoir volume was found to be reduced to 15 cc of medication from 20 cc during the seventh year of therapy. There was a report of a fall. Routine reservoir exchange at the end of battery life revealed that the bottom shield of the reservoir was indented. CONCLUSIONS: Inability to refill the medication to full capacity should be an indication to investigate device deformation. Information about exposure to hyperbaric therapy or local trauma should be obtained.

Complications associated with stellate ganglion nerve block: a systematic review.

Stellate ganglion nerve blockade (SGNB) is a vital tool in our armamentarium for the treatment of various chronic pain syndromes. SGNB can be performed using the traditional landmark-based approach, or with image guidance using either fluoroscopy or ultrasound. In this review, we systematically analyzed reported SGNB-related complications between 1990 and 2018. Seven databases were queried for SGNB between January 1, 1990 and November 27, 2018. Search results of the complications associated with SGNB were reported as per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses recommendations. Out of a total of 1909 articles, 67 articles met our inclusion criteria, yielding 260 cases with adverse events. In 134 of the 260 (51.5%) cases, SGNB was performed with image guidance. Sixty-four (24.6%) and 70 (26.9%) of the complication cases reported the use of ultrasound and fluoroscopy guidance, respectively. One hundred and seventy-eight (68.4%) patients had medication-related or systemic side effects, and 82 (31.5%) had procedure-related or local side effects. There was one report of death due to massive hematoma leading to airway obstruction. There was one case report of quadriplegia secondary to pyogenic cervical epidural abscess and discitis following an SGNB. Complications following SGNB have been reported with both landmark-based techniques and with imaging guidance using fluoroscopy or ultrasound. In our systematic review, most adverse events that were reported occurred during or shortly after SGNB. Vigilance, American Society of Anesthesiologists standard monitors for conscious sedation, and accessibility to resuscitation equipment are vital to the safe performance of SGNB.

Ultrasound-Assisted Versus Fluoroscopic-Guided Lumbar Sympathetic Ganglion Block: A Prospective and Randomized Study.

BACKGROUND: Fluoroscopy (FL)-guided lumbar sympathetic ganglion block (LSGB) is widely performed to diagnose and manage various diseases associated with sympathetically maintained pain. Recently, numerous ultrasound (US)-assisted procedures in pain medicine have been attempted, showing an advantage of low radiation exposure. This randomized, prospective trial compared the procedural outcomes and complications between FL-guided and US-assisted LSGBs. METHODS: Fifty LSGBs were randomly divided into 2 groups: FL-guided (FL group) or US-assisted (US group) LSGB group. Both groups received FL-guided or US-assisted LSGB with 10 mL of 0.25% levobupivacaine. The primary end point was the total procedure time. Secondary outcomes were success rate, imaging time, onset time (based on temperature rise), dosage of radiation exposure, other procedure-related outcomes, and complications. RESULTS: Total procedure time and success rate were not statistically different between the 2 groups, whereas imaging time of the US group was longer than that of the FL group (P = .012). The onset time was faster in the US group (P = .019), and bone touching during the procedure was less frequent in the US group (P = .001). Moreover, radiation exposure was significantly lower in the US group than in the FL group (P < .001). No serious complications were reported in all patients. CONCLUSIONS: US-assisted LSGB appears to be a feasible method with the added benefit of lower radiation exposure. In our study, we did not find an advantage of US-assisted LSGB over FL-guided LSGB in terms of performance time.

Review of Sympathetic Blocks: Anatomy, Sonoanatomy, Evidence, and Techniques.

The autonomic nervous system is composed of the sympathetic and parasympathetic nervous systems. The sympathetic nervous system is implicated in situations involving emergent action by the body and additionally plays a role in mediating pain states and pathologies in the body. Painful conditions thought to have a sympathetically mediated component may respond to blockade of the corresponding sympathetic fibers. The paravertebral sympathetic chain has been targeted for various painful conditions. Although initially injected using landmark-based techniques, fluoroscopy and more recently ultrasound imaging have allowed greater visualization and facilitated injections of these structures. In addition to treating painful conditions, sympathetic blockade has been used to improve perfusion, treat angina, and even suppress posttraumatic stress disorder symptoms. This review explores the anatomy, sonoanatomy, and evidence supporting these injections and focuses on ultrasound-guided/assisted technique for the performance of these blocks.

Ultrasound-Guided Peristyloid Steroid Injection for Eagle Syndrome.

The styloid process arising from the temporal bone is normally about 2.5 cm in length. For various reasons, including trauma and inflammation, it may become elongated. This elongated styloid process, when symptomatic with clinical signs and symptoms suggestive of local compression or neuropathic pain, is termed Eagle syndrome. Glossopharyngeal neuralgia is characterized by intermittent shooting sharp pain in the jaw, throat, tongue, and ear. Conservative management includes anticonvulsants, tricyclic antidepressants, and anti-inflammatory agents. Interventional and surgical options are pursued when these fail. Fluoroscopy is usually used to position the needle adjacent to the styloid process for injecting steroid and or local anesthetic. We describe a case of a 41-year-old woman with Eagle syndrome who failed conservative management and subsequently underwent an ultrasound-guided peristyloid steroid injection with short-duration pain relief.