External oblique intercostal plane block vs port-site infiltration for postoperative analgesia after laparoscopic cholecystectomy: a randomized trial

Effective postoperative analgesia after laparoscopic cholecystectomy (LC) remains challenging because postoperative pain is multifactorial and may negatively affect recovery. Although port-site infiltration (PSI) is widely recommended as part of multimodal analgesia, its analgesic effect may be limited to superficial somatic pain. The external oblique intercostal plane block (EOIPB) has emerged as a promising fascial plane block for upper abdominal surgery; however, evidence of its efficacy in LC remains limited. This study compared the analgesic efficacy of bilateral EOIPB and PSI after LC. In this prospective, randomized trial, 60 patients undergoing elective LC were included and received either bilateral ultrasound-guided EOIPB (n = 30) or PSI (n = 30). Both groups received a standardized multimodal analgesic regimen including intravenous paracetamol and tenoxicam together with postoperative morphine PCA. The primary outcome was cumulative opioid consumption during the first 24 postoperative hours, expressed as intravenous morphine milligram equivalents (IV MME). Secondary outcomes included pain scores at rest and during coughing, cumulative IV MME at 12 h, time to first PCA morphine request, QoR-15 score at 24 h, rescue analgesic and antiemetic requirements, and perioperative complications. Twenty-four-hour cumulative IV MME was significantly lower in the EOIPB group than in the PSI group (20.38 ± 6.90 mg vs. 29.14 ± 7.96 IV MME; p < 0.001). Opioid consumption during the first 12 postoperative hours was also reduced in the EOIPB group (14.25 ± 5.25 vs. 20.29 ± 8.15 mg IV MME; p < 0.001). The time to the first PCA morphine request was significantly prolonged with EOIPB (25 [15] min vs. 20 [10] min; p = 0.013). Linear mixed-effects analysis showed significantly lower overall pain scores during coughing in the EOIPB group (group effect, p = 0.041), whereas the overall between-group difference in resting pain did not reach statistical significance (p = 0.052). Group × time interactions were not significant for either resting or coughing-related pain. In addition, QoR-15 scores at 24 h were significantly higher in the EOIPB group (128.50 ± 9.56 vs. 123.43 ± 9.18; p = 0.013). Rescue analgesic use, antiemetic requirement, and postoperative nausea and vomiting were comparable between the groups. Bilateral EOIPB provided superior opioid-sparing analgesia compared with PSI in patients who underwent LC. The EOIPB may be an effective component of multimodal analgesia for LC. ClinicalTrials.gov (Registration No: NCT07164664, registration date: 02 September 2025).