Effect of Liposomal Bupivacaine for Sciatic Nerve Block on Opioid Use in Patients Undergoing Maxillofacial Reconstruction with Free Fibular Flap: a randomized, controlled trial

Background We investigated the efficacy and safety of preoperative popliteal sciatic nerve block (PSNB) using liposomal bupivacaine (LB) to reduce preoperative opioid consumption and improve recovery quality in patients undergoing maxillofacial reconstruction with a free fibular flap. Methods Patients were randomly allocated into two groups. The PSNB group received ultrasound guided PSNB using 133 mg of LB after anesthesia induction. In the control group, patients underwent nerve block preparation procedures without puncture or drug injection. The primary endpoint was cumulative opioid consumption during the perioperative period (from anesthesia induction to 48 h post-surgery). Results A total of 74 patients were included in the intention-to-treat analysis. There was no significant difference in cumulative opioid consumption between the control group (3020 [2163,3570] µg of remifentanil equivalents) and the PSNB group (2856 [2204,3771] µg; p = 0.863). The incidence of moderate to severe pain at the donor site within 48 h after surgery was significantly lower in the PSNB group (3 [8.1%] of 37 patients) than in the control group (18 [48.6%] of 37 patients; p < 0.001). The consumption of rescue opioids was significantly reduced in the PSNB group (0 [0, 50]) compared with that in the control group (50 [0, 100]; p = 0.007). The subjective sleep quality numeric rating scale score was significantly lower in the PSNB group than in the control group (day of surgery: 6 [5, 8] vs . 8 [6, 9], p = 0.029; postoperative day 1: 5 [4, 5] vs . 7 [6, 8], p < 0.001; postoperative day 2: 5 [4, 6] vs . 6 [5, 8], p = 0.001). The incidence of postoperative nausea and vomiting was significantly lower in the PSNB group (0 [0.0%]) compared with that in the control group (5 [13.5%]; p = 0.021). There was no significant difference in the incidence of adverse events between the two groups. Conclusion Preoperative administration of PSNB by LB did not spare opioids during the intraoperative period, but significantly relieved postoperative pain at the donor site, reduced rescue opioid consumption, and improved postoperative sleep quality, without additional adverse events. Trial registration Clinicaltrials.gov. Identifier ChiCTR2400080944