Erector Spinae Plane Block Versus Thoracic Epidural Analgesia for Open Liver Resection

Background: Open liver resection is associated with severe postoperative pain. While thoracic epidural analgesia (TEA) is considered the gold standard for pain control, its clinical application is often limited by postoperative coagulation profile derangement, which increases the risk of epidural hematoma. Continuous erector spinae plane block (ESPB) has emerged as a promising, safer alternative with a lower risk of bleeding complications. Objective: This study aims to compare the postoperative analgesic efficacy, safety profiles, and impacts on respiratory function between ultrasound-guided continuous ESPB and TEA in patients undergoing elective open liver resection. Hypothesis: The investigators hypothesize that continuous ESPB using a programmed intermittent bolus (PIB) regimen is non-inferior to TEA regarding 72-hour postoperative pain scores at rest, while offering superior hemodynamic stability and fewer technique-related risks.