Anesthetic Management of Patients for Vagal Nerve Stimulator Placement: A Narrative Review

Vagal nerve stimulation (VNS) is an established neuromodulation therapy used in the treatment of drug-resistant epilepsy and treatment-resistant depression. This therapy is expanding to avenues in autonomic disorders, heart failure, and chronic migraine. Utilization of this therapy is continuing to grow, and anesthesiologists will increasingly encounter patients undergoing primary implantation or revision of VNS devices. Understanding of device mechanisms, implantation techniques, and physiologic responses to vagal stimulation is imperative to safer perioperative management. This narrative review summarizes current evidence regarding vagal nerve anatomy, VNS device components, perioperative assessment, intraoperative considerations, and postoperative complications. A targeted literature review was performed to identify clinical trials, cohort studies, device safety analyses, and review articles related to anesthetic management of VNS implantation. Preoperative considerations include evaluation of seizure control, prior surgical history, psychiatric comorbidities, and familiarity with magnet function for terminating or increasing stimulation. Intraoperatively, the proximity of the surgical field to the airway requires secure endotracheal tube positioning and alternes to displacement. Direct manipulation of the cervical vagus nerve can elicit bradycardia, hypotension, and, rarely, asystole. Further, electrocautery use should be minimized, with bipolar techniques being preferred to decrease the risk of lead or generator damage. Postoperative management involves appropriate analgesia without excess respiratory depression, prevention of seizure recurrence, and recognition of complications. Hematoma, pocket infection, lead fracture, pulse generator migration, and vocal cord dysfunction are device-related and transient physical complications. Overall, anesthetic management for VNS implantation must take an individualized and comprehensive approach that encompasses patient-specific factors, surgical technique, and device characteristics.