Comparison between bupivacaine liposome injectable suspension and ropivacaine as local anesthetics for transversus abdominis plane block in postoperative pain management after laparoscopic sleeve gastrectomy: a randomized controlled trial

BACKGROUND: Postoperative pain management is critical for optimizing enhanced recovery after surgery (ERAS) in laparoscopic sleeve gastrectomy (LSG), where transversus abdominis plane block (TAPB) is a standard analgesic technique. Ropivacaine, the most commonly used local anesthetic for TAPB in LSG, has a short duration of action (4-6 h), which may be insufficient to control pain for up to 72 h and increase opioid dependence. Bupivacaine liposome injectable suspension (BLIS) provides extended analgesia (24-72 h) but has not been rigorously compared to ropivacaine in LSG-specific TAPB regarding 72-h analgesic efficacy, opioid-sparing effects, or ERAS-related outcomes. This randomized controlled trial was designed to fill this evidence gap. METHODS: In a single-center randomized controlled trial, 60 patients undergoing LSG were randomized to receive TAPB with either bupivacaine liposomal suspension (n = 30) or ropivacaine (n = 30). The primary outcome was the VAS score from 4- to 72-h postsurgery. Secondary outcomes included analgesic drug use, motor function, sleep quality, and adverse events. RESULTS: Compared with Group R, patients in Group B exhibited lower VAS scores from 4 to 72 h postoperatively, significantly reduced patient-controlled analgesia use, and markedly less need for rescue NSAIDs-approximately 75% lower than Group R (6.7% vs. 30%, P = 0.02). Although both groups ambulated within 24 h, no significant differences were observed in deep sleep proportion (24.3% vs. 23.9%, P = 0.90) or incidence of adverse events (20% vs. 16.7%, P = 0.50). CONCLUSIONS: BLIS offers prolonged analgesic effects, extending up to 72 h, and significantly reduces the reliance on additional analgesics, making it a valuable option in multimodal pain management for LSG. However, its impact on enhancing ERAS-related outcomes requires further investigation. Trial registration registration number ChiCTR2500104979, registration date 2025-06-26 00:00:00 (retrospectively registered).