Efficacy of ultrasound-guided external oblique intercostal plane block in laparoscopic common bile duct exploration: A double-blinded randomized controlled study.

Laparoscopic common bile duct exploration (LCBDE) is a safe, reliable, cost-effective, and common treatment for common bile duct stones [,]. However, postoperative pain stimulation can easily lead to pain, tension, anxiety and other adverse emotions in patients, which affects the surgical outcome and prognosis and prolongs the hospital stay; therefore, effective analgesia is essential for patients undergoing LCBDE []. Opioids or epidural analgesia are the first choice for postoperative abdominal wall analgesia. However, they are associated with risks of hypotension, urinary retention, nausea, vomiting, and respiratory depression [–]. External oblique intercostal plane block (EOIPB) is a recent modified block technique that blocks the lateral and anterior cutaneous branches of the intercostal nerves from T6/7 to T10/11 for analgesia of the anterolateral upper abdominal wall []. Compared to other analgesia options, EOIPB is safer, simpler, less time-consuming, and has fewer complications []. Although some case series have demonstrated that EOIPB provides effective analgesia in upper abdominal surgeries [,], there is still a lack of randomized studies examining LCBDE. The study aimed to observe the efficacy of EOIPB in LCBDE. This study was carried out at the First Hospital of Qinhuangdao from March 2023 to February 2024 and was approved by the Ethics Committee of the First Hospital of Qinhuangdao (ID: 2023KZ077). The study was registered on ClinicalTrials.gov (, registration date: 17/10/2024). It adheres to the principles outlined in the Declaration of Helsinki and the CONSORT 2010 guidelines. Informed consent was obtained from all enrolled patients concerning study enrollment, anonymized data collection, and publication.