Regional Analgesia Techniques for Laparoscopic Cholecystectomy

Overview

This single-center, prospective, randomized controlled trial aims to compare the effects of paravertebral block (PVB), external oblique intercostal (EOI) block, and intravenous patient-controlled analgesia (PCA) with tramadol on postoperative pain and opioid consumption in patients undergoing elective laparoscopic cholecystectomy. The primary endpoint is total tramadol consumption within 24 hours postoperatively. Secondary outcomes include pain scores, additional analgesic use, incidence of nausea/vomiting, mobilization time, and length of hospital stay.

This single-center, prospective, randomized controlled clinical trial aims to compare the analgesic efficacy and opioid-sparing effects of paravertebral block (PVB), external oblique intercostal (EOI) block, and intravenous patient-controlled analgesia (IV PCA) in adult patients undergoing elective laparoscopic cholecystectomy (LC) under general anesthesia. Although laparoscopic cholecystectomy is a minimally invasive procedure, postoperative pain remains a significant clinical problem, particularly during the first 24 hours after surgery. Effective multimodal analgesia is essential to improve patient comfort, facilitate early mobilization, and reduce opioid-related side effects. Regional anesthesia techniques, such as PVB and EOI block, target both somatic and visceral components of pain and may offer superior postoperative analgesia compared with systemic opioid administration alone. After obtaining informed consent, eligible patients (aged 18-65 years, ASA I-III) scheduled for elective LC will be randomly assigned to one of three groups using the sealed envelope method: Group P (Paravertebral Block): After induction of general anesthesia, bilateral paravertebral blocks will be performed at thoracic levels with 0.25% bupivacaine (20 mL per side; total 40 mL). Group E (External Oblique Intercostal Block): After induction, bilateral EOI blocks will be performed using 0.25% bupivacaine (20 mL per side; total 40 mL) injected into the fascial plane between the external oblique and intercostal muscles under ultrasound guidance. Group C (Control): Patients will receive standard general anesthesia followed by IV PCA with tramadol (maximum dose 400 mg/24h) and IV paracetamol 1 g every 8 hours. All patients will receive standard intraoperative monitoring and anesthesia management. Postoperative analgesia will be evaluated using an 11-point Numerical Rating Scale (NRS, 0-10) both at rest and during movement at 20 minutes, 6 hpurs, 12 hours, and 24 hours after surgery. If the NRS score is ≥4 in the postoperative care unit, IV morphine (0.05 mg/kg), If the NRS score is ≥7 Meperidine 0.3 mg/kg will be administered as rescue analgesia. The primary outcome is total tramadol consumption within the first 24 postoperative hours. Secondary outcomes include pain scores at predefined time points, requirement for rescue analgesics, incidence of postoperative nausea and vomiting (PONV), time to mobilization, and length of hospital stay. Patients will be followed for 24 hours postoperatively. The anesthesia team performing the blocks will not participate in data collection. Pain assessments will be conducted by an investigator blinded to group allocation to minimize bias. This study will provide comparative data on two ultrasound-guided regional anesthesia techniques and systemic opioid-based analgesia for LC, aiming to identify the method that ensures optimal postoperative pain control with the least opioid requirement and side effects.