This prospective randomized controlled trial aims to evaluate whether the timing of ultrasound-guided subcostal transversus abdominis plane (TAP) block combined with rectus sheath block (RSB) affects postoperative pain in patients undergoing laparoscopic cholecystectomy.

Participants will be randomly assigned to receive the combined regional blocks either before surgical incision or after completion of surgery. The primary outcome is postoperative pain intensity measured using a numerical rating scale. Secondary outcomes include opioid consumption, incidence of postoperative nausea and vomiting, and other recovery parameters.

The results of this study may help optimize the timing of abdominal wall blocks to improve postoperative analgesia and recovery following laparoscopic cholecystectomy.

Postoperative pain after laparoscopic cholecystectomy remains a significant clinical concern despite the minimally invasive nature of the procedure. Ultrasound-guided abdominal wall blocks, including subcostal transversus abdominis plane (TAP) block and rectus sheath block (RSB), are widely used to reduce postoperative pain and opioid requirements. However, the optimal timing of block administration relative to surgical incision remains unclear.

This prospective, single-center, randomized controlled trial will compare the analgesic efficacy of pre-incisional versus post-operative administration of combined ultrasound-guided subcostal TAP block and RSB in adult patients undergoing elective laparoscopic cholecystectomy under general anesthesia.

Participants will be randomized in a 1:1 ratio using block randomization with randomly permuted block sizes. Standardized general anesthesia and postoperative analgesia protocols will be applied to all participants.

The primary outcome will be postoperative pain intensity measured using a numerical rating scale at predefined time points after surgery. Secondary outcomes will include cumulative opioid consumption, incidence of postoperative nausea and vomiting, rescue analgesic requirements, and recovery profiles.

The findings of this study are expected to provide evidence for optimizing the timing of abdominal wall block administration to improve postoperative analgesia and patient recovery after laparoscopic cholecystectomy.

Inclusion Criteria:

• Elective laparoscopic cholecystectomy
• Adults aged 18 to 80 years
• Ability to understand the study procedures and provide informed consent
• American Society of Anesthesiologists (ASA) physical status I-III

Exclusion Criteria:

• Presence of significant pain unrelated to the target disease that may interfere with pain assessment
• Known allergy or contraindication to study medications (ropivacaine, acetaminophen, nefopam, or pethidine)
• Planned single-port laparoscopic cholecystectomy
• American Society of Anesthesiologists (ASA) physical status IV or higher
• Infection of the abdominal wall or skin at the injection site, or anatomical abnormalities of the abdominal wall
• Major neurological, psychiatric, or systemic diseases that may affect pain perception, treatment response, or study evaluation
• Requirement for postoperative mechanical ventilation
• Pregnancy or breastfeeding
• Considered unsuitable for the study by the investigator
• Refusal to participate or inability to provide informed consent

Participants and outcome assessors will be blinded to group allocation. The anesthesiologist performing the block will not be blinded due to the nature of the intervention.