Patients with implanted spinal cord stimulators (SCS) present to the anesthesia care team for management at many different points along the care continuum. Currently, the literature is sparse on the perioperative management. What is available is confusing; monopolar electrocautery is contraindicated but often used, full body magnetic resonance imaging (MRI) is safe with particular systems but with other manufactures only head and specific extremities exams are safe. Moreover, there are anesthetizing locations outside of the operating room where implanted SCS can interact with surrounding medical equipment and pose significant risk to patient and device.The objective of this review is to present relevant known literature about the safe management of SCS in the perioperative period and to begin to develop recommendations.A review of current literature and each manufacturers' labeling was performed to assess risk of interference and patient harm between SCS and technology used in and around typical anesthetizing locations.A systematic search of the literature was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement. A computerized search was conducted for English articles in print up to April 2016 via PubMed www.ncbi.nlm.nih.gov/pubmed; EMBASE www.embase.com; and Cochrane Library www.thecochranelibrary.com. Search terms included "spinal cord stimulator AND MRI," "spinal cord stimulator AND ECG," "spinal cord stimulator AND implanted cardiac device," "spinal cord stimulator AND electrocautery," and "spinal cord stimulator AND obstetrics." In addition, a search of Google and Google Scholar was performed. Websites of SCS manufactures were reviewed.Generalized recommendations include turning the amplitude of the SCS to the lowest possible SETTING and turning off prior to any procedure. Monopolar electrocautery is contraindicated but is still often utilized; placing grounding pads as far away from the device can reduce the risk to device and patient. Bipolar cautery is favored. Implanted cardiac devices can interfere with SCS, but risks can be minimized. Neuraxial anesthesia can be attempted in a patient with implanted SCS, provided the device is not in the expected path. MRI labeling differences present the biggest difference among SCS manufactures. Medtronic's SureScan SCS, Boston Scientific's Precision system, St. Jude's Proclaim, and Stimwave's Freedome SCS are full body MRI compatible under specific conditions, while other manufacturers have labeling that restricts exams of the trunk and certain extremities.This review was intended to be a comprehensive, cumulative review of recommendations for perioperative SCS management; however, the limitations of a review of this nature is the complete reliance on previously published research and the availability of these studies using the methods outlined.SCS is being used earlier in the treatment algorithm for patients with chronic pain. The anesthesia care team needs working knowledge of where the device resides in the neuraxial space and what risks different medical technologies pose to the patient and device. This understanding will lead to appropriate perioperative management which can reduce risk and improve patient outcomes.
Spinal cord stimulators are most often placed through a percutaneous approach using minimal sedation and local anesthesia to facilitate intraoperative testing. However, when leads need to be placed using a laminectomy incision additional anesthesia is required which can complicate intraoperative testing. There is no consensus as to the best anesthetic choice when laminectomy-placed leads are required.We present 2 cases where spinal cord stimulator leads were implanted through a surgical laminectomy under sedation using dexmedetomidine infusion and local anesthesia to provide a cooperative patient for intraoperative testing.Patient #1: A 40-year-old female with Complex Regional Pain Syndrome secondary to an automobile accident who had good pain control with a spinal cord stimulator until a lead fracture resulted in loss of stimulation. She required a laminectomy-placed lead which was implanted under dexmedetomidine infusion and local anesthesia. Patient #2: A 54-year-old female with Failed Back Syndrome who had good pain control until a lead fracture resulted in loss of stimulation. She underwent a laminectomy-placed lead, new battery pocket, and removal of the old system under a dexmedetomidine infusion and local anesthesia.Report of only 2 cases.The anesthetic management from a laminectomy-placed spinal cord stimulator can present a difficult choice. A general anesthetic or even deep sedation can provide good operative conditions but limits intraoperative testing or in the case of deep sedation risks losing the airway in the prone position. On the other hand, minimal sedation, which facilitates intraoperative testing, can make the surgical procedure extremely uncomfortable or even unbearable. Dexmedetomidine infusion and local anesthesia provide sedation for the operative portions while rendering the patient alert and cooperative during intraoperative testing.
Introduction: The benefits of opioid therapy must be balanced by any adverse effects. In recent years, prescription opioids have been increasingly prescribed, but have also been associated with increased abuse, overdose and death.Areas covered: This review will categorize the common risks of opioid administration. Recognized adverse effects of opioid therapy include constipation, tolerance, endocrinopathies, sleep disorders, cognitive effects, respiratory depression, overdose and addiction. Studies have shown that there is increased risk of overdose and death with higher daily opioid doses, particularly above a morphine equivalent oral daily dose of 100 milligrams. Extended-release/long acting (ER/LA) opioid formulations may be beneficial for the compliant patient, yet may expose a higher risk for abuse if used inappropriately since each tablet carries a larger dose of medication.Expert opinion: Prospective, controlled one-year trials are needed to establish the efficacy and safety profile of chronic opioid therapy. In addition to the well known side effects of chronic opioid therapy, the influence and serious effect of opioids on sleep and central sleep apnea is only recently being investigated. The lowest possible daily opioid must be used to manage chronic pain, and all clinicians should be cautious in the use of daily morphine equivalent doses above 50-100 milligrams.
