Ultrasound-Guided Intermediate Cervical Plexus Block for Postoperative Analgesia in Vagus Nerve Stimulation Surgery

This prospective, randomized, double-blind, placebo-controlled clinical trial aims to evaluate the analgesic efficacy of ultrasound-guided intermediate cervical plexus block (ICB) in patients undergoing vagus nerve stimulation (VNS) implantation surgery under general anesthesia. Participants are randomly assigned to receive either an ultrasound-guided ICB with 10 mL of 0.25% bupivacaine or a placebo injection with 10 mL of normal saline following induction of general anesthesia. The primary outcome is total postoperative morphine consumption during the first 24 hours after surgery. Secondary outcomes include intraoperative remifentanil consumption, postoperative pain intensity assessed using the Numeric Rating Scale (NRS), time to first analgesic request, length of hospital stay, and postoperative seizure incidence.

Inclusion Criteria: * Adults aged 18-60 years * American Society of Anesthesiologists (ASA) physical status II-III * Drug-resistant epilepsy * Scheduled for elective vagus nerve stimulation implantation surgery under general anesthesia * Written informed consent obtained Exclusion Criteria: * Allergy or contraindication to local anesthetics * Coagulopathy or current anticoagulant therapy * Infection at the injection site * Pregnancy or breastfeeding * Severe pulmonary disease * Inability to understand or use the Numeric Rating Scale (NRS) * Refusal to participate