Simultaneous Use of Neurostimulators in Patients With a Preexisting Cardiovascular Implantable Electronic Device

Military concerns for chronic pain stimulator devices

Spinal cord stimulators (SCS) and peripheral nerve stimulators (PNS) are increasingly used in the treatment of chronic pain, allowing more patients to resume working and return to activities. Military service members face environmental and occupational hazards that expose them to mechanical and electromagnetic forces, both clinical and industrial, that could potentially alter their function. While there are reports of individual hazards, the risk appears to be nominal based on the large number of devices in use and the limited reported complications with these devices. Since a variety of hazards encountered by military patients have the potential to alter SCS and PNS devices, a brief discussion of each patient's specific exposures and related hazards should occur prior to placement. Overall, these devices have demonstrated safety in hazardous areas and few military patients have contraindications for placement based on these factors alone.

Ethical Considerations in the Implantation of Neuromodulatory Devices

OBJECTIVES

Neuromodulatory devices are increasingly used by neurosurgeons to manage a variety of chronic conditions. Given their potential benefits, it is imperative to create clear ethical guidelines for the use of these devices. We present a tiered ethical framework for neurosurgeon recommendations for the use of neuromodulatory devices.

MATERIALS AND METHODS

We conducted a literature review to identify factors neurosurgeons should consider when choosing to offer a neuromodulatory device to a patient.

RESULTS

Neurosurgeons must weigh reductions in debilitating symptoms, improved functionality, and preserved quality of life against risks for intraoperative complications and adverse events due to stimulation or the device itself. Neurosurgeons must also evaluate whether patients and families will maintain responsibility for the management of neuromodulatory devices. Consideration of these factors should occur on an axis of resource allocation, ranging from provision of neuromodulatory devices to those with greatest potential benefit in resource-limited settings to provision of neuromodulatory devices to all patients with indications in contexts without resource limitations. Neurosurgeons must also take action to promote device effectiveness throughout the duration of care.

CONCLUSIONS

Weighing risks and benefits of providing neuromodulatory devices and assessing ability to remain responsible for the devices on the level of the individual patient indicate which patients are most likely to achieve benefit from these devices. Consideration of these factors on an axis of resource allocation will allow for optimal provision of neuromodulatory devices to patients in settings of varied resources. Neurosurgeons play a primary role in promoting the effectiveness of these devices.

Coexistence of deep brain stimulators and cardiac implantable electronic devices: A systematic review of safety

As the number of patients implanted with deep brain stimulation systems increases, coexistence with cardiac implantable electronic devices (CIEDs) poses questions about safety. We systematically reviewed the literature on coexisting DBS and CIED. Eighteen reports of 34 patients were included. Device-device interactions were reported in 6 patients. Sources of complications were extensively reviewed and cautious measures which could be considered as part of a standard checklist for careful consideration are suggested.

Burst Stimulation of the Thoracic Spinal Cord near a Cardiac Pacemaker in an Elderly Patient with Postherpetic Neuralgia: A Case Report

New developments in spinal cord stimulation (SCS) have improved the treatment of patients with chronic pain. Although the overall safety of modern SCS has been established, there are no published reports regarding safety considerations when implanting a burst-mode spinal cord stimulator in patients with permanent cardiac pacemakers (PCPs). An 80-year-old man with a complete atrioventricular block implanted with a PCP was considered as a candidate for burst-mode SCS due to well-established postherpetic neuralgia (>180 days after rash). Cardiac monitoring during the burst-mode spinal cord stimulator trial and insertion did not indicate any interference. After the insertion of the burst-mode spinal cord stimulator, the patient showed functional improvement and significant pain relief. The safety of traditional tonic-mode SCS in patients with PCP has been previously reported. This is the first case report describing the safe and effective use of burst-mode SCS in a patient with PCP.

Deep Brain Stimulation in Patients With Concomitant Cardiac Pacemakers: A Case Series

BACKGROUND

Deep brain stimulation (DBS) is a treatment modality increasingly utilized in the management of neurological and psychiatric conditions. Neurosurgical technical considerations and contraindications have yet to be thoroughly characterized in the literature. The patient population for DBS includes many elderly patients with multiple comorbidities who require treatments and investigations that expose them to electromagnetic fields of varying strengths and durations, including other implanted electromodulatory devices.

OBJECTIVE

To determine if clinically significant interference arises between DBS and cardiac pacemaker systems.

METHODS

Here we audited 8 patients, mean age 72, with cardiac pacemakers and DBS implanted from 2007 to 2015. We investigated details of their neurological and electrocardiological treatment and progress and sought evidence for interference between the two systems.

RESULTS

We found no evidence of DBS dysfunction, and only one case of abnormal pacemaker interrogation 2 yr post-DBS implantation was found, which was thought to be secondary to a medication issue rather than neuromodulation interference.

CONCLUSION

Our research reassures the clinician that pacemakers and DBS systems do not appear to affect one another and provides guidance on minimizing possibility of this.

Development of an Educational Curriculum for Spinal Cord Stimulation

BACKGROUND

Spinal cord stimulators (SCSs) are used for treating chronic pain. The number of SCSs implanted each year is on the increase. The North American Neuromodulation Society (NANS) education committee aimed to develop a SCS curriculum as a tool to guide physicians at different training levels, based on the most recent evidence.

MATERIAL AND METHODS

A multidisciplinary (anesthesiology, physical medicine, neurosurgery, and neurology), taskforce representing the education committee of the NANS met to develop a SCS curriculum following the Accreditation Council for Graduate Medical Education (ACGME) milestones. The task force used the best available evidence and knowledge to develop the curriculum. Once developed, the SCS curriculum was then approved by the NANS board.

RESULTS

The task force developed a SCS training curriculum. Milestones included patient care and procedural skills, system-based practice, medical knowledge, interpersonal communication, practice based learning and professionalism. Each milestone was defined for three categories, early learner, advanced learner, and practitioner.

CONCLUSION

A multidisciplinary task force of the NANS education committee developed a SCS training curriculum that defines ACGME milestones for basic learners, advanced learners, and practitioners.

Pacemaker and Defibrillator Implantation and Programming in Patients with Deep Brain Stimulation

The need for cardiac device implantation in patients receiving deep brain stimulation (DBS) is increasing. Despite the theoretical risk of the two systems interacting, there are no clear guidelines for cardiologists carrying out cardiac device implantation in this population. We performed a review of the literature and describe 13 case reports in which patients have both DBS and a cardiac pacemaker or ICD implanted. Except for one early study, in which an ICD shock reset the deep brain stimulator, no significant interactions have been reported. We discuss the potential interactions between DBS and cardiac devices, and provide practical advice for implanting cardiologists. We conclude that, provided that specific precautions are taken, cardiac device implantation is likely to be safe in patients with DBS.

Some Non-FDA Approved Uses for Neuromodulation in Treating Autonomic Nervous System Disorders: A Discussion of the Preliminary Support

INTRODUCTION

Neuromodulation, including cavernous nerve stimulation, gastric electrical stimulation, deep brain stimulation, and vagus nerve stimulation, has been used with success in treating several functional disease conditions. The FDA has approved the use of neuromodulation for a few indications. We discuss in our review article the evidence of using neuromodulation for treating some important disorders involving the autonomic nervous system that are not currently FDA approved.

METHODS

This was a review article that included a systematic online web search for human clinical studies testing the efficacy of neuromodulation in treating erectile dysfunction, gastroparesis, gastroesophageal reflux disease, obesity, asthma, and heart failure. Our review includes all feasibility studies, nonrandomized clinical trials, and randomized controlled trials.

RESULTS

Our systematic literature search found 3, 4, 5, 4, 1, and 4 clinical studies relating to erectile dysfunction, gastroparesis, gastroesophageal reflux disease, obesity, asthma, and heart failure, respectively.

CONCLUSION

This review article shows preliminary support based on clinical studies that neuromodulation can be of benefit for patients with important autonomic nervous system disease conditions that are not currently approved by the FDA. All of these investigational uses are encouraging; further studies are necessary and warranted for all indications discussed in this review before achieving FDA approval.

Do we need to establish guidelines for patients with neuromodulation implantable devices, including spinal cord stimulators undergoing nonspinal surgeries?

Background:

Spinal cord stimulation is currently approved to treat chronic intractable pain of the trunk and limbs. However, such implantable electronic devices are vulnerable to external electrical currents and magnetic fields. Within the hospitals and modern operating rooms (ORs), there is an abundance of electrical devices and other types of equipment that could interfere with such devices. Despite the increasing number of patients with neuromodulation implantable devices, there are no written guidelines available or consensus of cautions for such patients undergoing unrelated surgery.

Case Descriptions:

A 60-year-old female with a permanent St. Jude's spinal cord stimulator (SCS) presented for open total abdominal hysterectomy. Both the anesthesia and gynecology staffs were aware of the device presence, but were unaware of any precautions regarding intraoperative management. The device was found to be nonmagnetic resonance imaging compatible, and bipolar cautery was used instead of monopolar cautery. A 59-year-old female with a 9-year-old permanent Medtronic SCS, presented for right total hip arthroplasty. The device was switched off prior to entering the OR, bipolar cautery was used, and grounding pads were placed away from her battery site. In each case, the manufacturer's representative was contacted preoperative. Both surgeries proceeded uneventfully.

Conclusions:

The Food and Drug Administration safety information manual warns about the use of diathermy, concomitant implanted stimulation devices, lithotripsy, external defibrillation, radiation therapy, ultrasonic scanning, and high-output ultrasound, all of which can lead to permanent implant damage if not turned off prior to undertaking procedures. Lack of uniform guidelines makes intraoperative management, as well as remote anesthesia care of patients with previously implanted SCSs unsafe.

The appropriate use of neurostimulation of the spinal cord and peripheral nervous system for the treatment of chronic pain and ischemic diseases: the Neuromodulation Appropriateness Consensus Committee

INTRODUCTION

The Neuromodulation Appropriateness Consensus Committee (NACC) of the International Neuromodulation Society (INS) evaluated evidence regarding the safety and efficacy of neurostimulation to treat chronic pain, chronic critical limb ischemia, and refractory angina and recommended appropriate clinical applications.

METHODS

The NACC used literature reviews, expert opinion, clinical experience, and individual research. Authors consulted the Practice Parameters for the Use of Spinal Cord Stimulation in the Treatment of Neuropathic Pain (2006), systematic reviews (1984 to 2013), and prospective and randomized controlled trials (2005 to 2013) identified through PubMed, EMBASE, and Google Scholar.

RESULTS

Neurostimulation is relatively safe because of its minimally invasive and reversible characteristics. Comparison with medical management is difficult, as patients considered for neurostimulation have failed conservative management. Unlike alternative therapies, neurostimulation is not associated with medication-related side effects and has enduring effect. Device-related complications are not uncommon; however, the incidence is becoming less frequent as technology progresses and surgical skills improve. Randomized controlled studies support the efficacy of spinal cord stimulation in treating failed back surgery syndrome and complex regional pain syndrome. Similar studies of neurostimulation for peripheral neuropathic pain, postamputation pain, postherpetic neuralgia, and other causes of nerve injury are needed. International guidelines recommend spinal cord stimulation to treat refractory angina; other indications, such as congestive heart failure, are being investigated.

CONCLUSIONS

Appropriate neurostimulation is safe and effective in some chronic pain conditions. Technological refinements and clinical evidence will continue to expand its use. The NACC seeks to facilitate the efficacy and safety of neurostimulation.

Spinal cord stimulation is safe and feasible in patients with advanced heart failure: early clinical experience

AIMS

Pre-clinical work suggests that upper thoracic spinal cord stimulation (SCS) may have therapeutic effects in the treatment of heart failure (HF). We therefore aim to assess the safety and feasibility of SCS in HF patients.

METHODS AND RESULTS

A prospective, randomized, double-blind, crossover pilot study was conducted in symptomatic HF patients receiving optimal medical therapy. Patients were implanted with an SCS system and randomized to an SCS-ACTIVE, delivered at 90% paraesthesia threshold, or an SCS-INACTIVE phase for 3 months, followed by a 1-month washout period and crossover to the alternative phase. The safety of SCS therapy was assessed by death and cardiac events. Implantable cardioverter defibrillator (ICD) function in the presence of SCS was tested by defibrillation testing during SCS system implant and review of real-time and stored electrograms during follow-up. The efficacy of SCS therapy was assessed by changes in patient symptoms, LV function, and BNP level. Nine patients were investigated. In all cases, ICD sensing, detection, and therapy delivery were unaffected by SCS. During follow-up, one patient died and one was hospitalized for HF while in the SCS-INACTIVE phase, and two patients had HF hospitalizations during the SCS-ACTIVE phase. Symptoms were improved in the majority of patients with SCS, while markers of cardiac structure and function were, in aggregate, unchanged.

CONCLUSION

This study shows that an SCS system can be safely implanted in patients with advanced HF and that the SCS system does not interfere with ICD function.

Implantation of a cardiac resynchronization therapy defibrillator in a patient with bilateral deep brain stimulator: feasibility and technique

Uncommonly, a patient with a NeuroStimulator Device (NSD) for a neurologic indication requires a cardiovascular implantable electronic device (CIED) for a cardiac indication. Typically in those with a unilateral pectoral NSD, the contralateral pectoral space is used for CIED implantation; however, in very rare occasions the patient has bilateral pectoral NSDs which makes subsequent implantation of a CIED challenging both because of placement and device interaction. Herein, we introduce the case of a 68-year-old gentleman with bilateral pectoral deep brain stimulators for Parkinsonism who received cardiac resynchronization therapy-defibrillator (CRT-D) for advanced heart failure. The CRT-D generator was implanted in the abdomen and the CRT-D leads were placed through a minimally invasive epicardial approach. Both devices were tested without any evidence of device interaction.