EOIB for Pain After Laparoscopic Cholecystectomy

This prospective, randomized, controlled, assessor-blinded trial will evaluate whether bilateral ultrasound-guided external oblique intercostal block (EOIB) reduces postoperative opioid consumption and improves pain control after laparoscopic cholecystectomy, compared with no block.

Inclusion Criteria: * Aged 18-85 years, regardless of gender * American Society of Anesthesiologists (ASA) physical status classification I-III * Scheduled for elective laparoscopic cholecystectomy * Ability to use the intravenous patient-controlled analgesia (IV PCA) system Exclusion Criteria: * Hepatic disease (e.g., liver enzyme levels ≥ 2× the upper limit of normal) * Renal disease (e.g., serum creatinine levels ≥ 2× the upper limit of normal) * Allergy or known hypersensitivity to local anesthetics * Females who are pregnant or lactating * Conversion to open surgery * Coagulopathy or current use of anticoagulant medications * Opioid use for more than 2 weeks in the past 6 months