EOI Block vs. TAP Block in Minimally Invasive Hepatectomy

This study aims to compare the analgesic efficacy of two different ultrasound-guided nerve blocks-the External Oblique Intercostal (EOI) block and the Subcostal Transversus Abdominis Plane (TAP) block-in patients undergoing minimally invasive hepatectomy. All participants will receive standardized general anesthesia and perioperative care at Seoul National University Hospital. Following anesthesia induction, patients will be randomly assigned to receive either an EOI block or a subcostal TAP block with 0.375% ropivacaine to provide regional pain relief. Postoperative pain will be managed using a combination of scheduled non-opioid analgesics and a fentanyl-based patient-controlled analgesia (PCA) device. The primary objective is to evaluate which regional technique more effectively reduces cumulative opioid consumption during the first 24 hours after surgery. Additionally, the study will assess pain intensity using the Numerical Rating Scale (NRS), the incidence of postoperative nausea and vomiting, and the overall recovery profile, including the time to first ambulation.

Inclusion Criteria: Scheduled to undergo elective robotic or laparoscopic minimally invasive hepatectomy Exclusion Criteria: * American Society of Anesthesiologists physical status IV or higher * History of chronic pain or current use of analgesics, antidepressants, or anticonvulsants for pain management * Known hypersensitivity to general anesthetics, opioids, or local anesthetics * Conversion to open hepatectomy * Requirement for mechanical ventilation for more than 2 hours within 48 hours postoperatively * Any other clinical condition that makes the patient unsuitable for participation in the study.