This prospective randomized controlled trial is designed to evaluate the analgesic efficacy of ultrasound-guided rectointercostal plane block (RICPB) in patients undergoing elective laparoscopic cholecystectomy. Patients will be randomized to receive unilateral right-sided RICPB at the end of surgery. Postoperative opioid consumption, Numeric Rating Scale (NRS) pain scores, and postoperative complications will be assessed to determine the effectiveness of RICPB in postoperative pain management.

Laparoscopic cholecystectomy is one of the most commonly performed abdominal surgical procedures. Although it is considered a minimally invasive technique, patients frequently experience moderate postoperative pain resulting from trocar insertion sites, surgical manipulation, and irritation of the abdominal wall and peritoneum. Effective postoperative pain management is essential to facilitate early mobilization, improve patient comfort, reduce opioid consumption, and enhance recovery.

The rectointercostal plane block (RICPB) is an ultrasound-guided fascial plane block that has recently emerged as a potential analgesic technique for upper abdominal surgery. By depositing local anesthetic between the rectus abdominis muscle and the costal cartilages/intercostal muscles, RICPB may provide analgesia to the anterior upper abdominal wall. However, evidence regarding its effectiveness in laparoscopic cholecystectomy remains limited.

This single-center, prospective, randomized controlled trial is designed to evaluate the analgesic efficacy of ultrasound-guided rectointercostal plane block in patients undergoing elective laparoscopic cholecystectomy. Eligible patients aged 18-65 years with American Society of Anesthesiologists (ASA) physical status I-III will be enrolled after providing written informed consent. Participants will be randomly allocated in a 1:1 ratio to either the RICPB group or the control group.

Patients assigned to the RICPB group will receive an ultrasound-guided unilateral right-sided rectointercostal plane block with 30 mL of 0.25% bupivacaine at the end of surgery before emergence from anesthesia. Patients in the control group will receive conventional port-site local anesthetic infiltration according to institutional practice. All patients will undergo a standardized general anesthesia protocol and receive the same multimodal postoperative analgesic regimen.

Postoperative pain assessments will be performed using the Numeric Rating Scale (NRS). Opioid consumption, pain scores and postoperative complications, including postoperative nausea and vomiting (PONV), will be recorded during the first 24 postoperative hours.

The primary outcome of the study is cumulative opioid consumption during the first 24 postoperative hours. Secondary outcomes include postoperative NRS pain scores, rescue analgesic requirements, and the incidence of postoperative complications. The study aims to determine whether ultrasound-guided rectointercostal plane block provides superior postoperative analgesia compared with conventional port-site local anesthetic infiltration in patients undergoing laparoscopic cholecystectomy.

Inclusion Criteria:

• Age between 18 and 65 years
• American Society of Anesthesiologists (ASA) physical status I-III
• Scheduled for elective laparoscopic cholecystectomy
• Body mass index (BMI) between 18 and 35 kg/m²
• Ability to understand the study procedures and provide written informed consent

Exclusion Criteria:

• Refusal to participate or inability to provide informed consent
• Known allergy or hypersensitivity to local anesthetics, opioids, or study medications
• Chronic opioid use or chronic pain syndrome
• Coagulation disorders or ongoing anticoagulant therapy
• Infection at the planned injection site
• Pregnancy or breastfeeding
• Cognitive impairment or inability to communicate pain scores
• Severe hepatic, renal, cardiac, or respiratory disease judged by the investigator to interfere with study participation
• Conversion from laparoscopic to open surgery
• Previous upper abdominal surgery that may interfere with the block technique or pain assessment

Participants will be unaware of group allocation. Postoperative assessments, including pain scores, opioid consumption, and postoperative complications, will be performed by an independent outcomes assessor who is blinded to treatment assignment. The anesthesiologist performing the intervention will not be blinded due to the nature of the procedure.