Abstract
BACKGROUND: This study compared the analgesic effects and adverse effects of liposomal bupivacaine and bupivacaine in patients undergoing posterior lumbar interbody fusion (PLIF) with retrolaminar block (RLB). The study evaluated the efficacy and safety of liposomal bupivacaine for postoperative analgesia in patients undergoing PLIF. METHODS: A total of 70 patients undergoing elective PLIF were enrolled and randomly divided into two groups: the liposomal bupivacaine group (LB group, n = 35) and the bupivacaine group (B group, n = 35), for RLB. The primary outcomes were postoperative 30-minute, 6-hour, 12-hour, 18-hour, 24-hour, 36-hour, 48-hour, and 72-hour static visual analog scale (VAS) scores and perioperative opioid consumption. Secondary outcomes included bupivacaine blood concentrations at 5 time points within 72 h after injection of the test drug, incidence of postoperative adverse events, Quality of Recovery-15 scores (QoR-15) of patients at 24 h, 48 h, and 72 h postoperatively, length of postoperative hospitalization, and changes in IL-6 and IL-10 after 2 h, 24 h, and 72 h of administration of the intervention. RESULTS: Compared with B group, resting VAS in the LB group were significantly decreased at 18 h, 24 h, 36 h, 48 h, and 72 h postoperatively (P = 0.003, 0.022, 0.009, 0.001, and 0.000, respectively). The QoR-15 scores of the LB group at 24 h, 48 h, and 72 h after surgery were significantly higher (P = 0.001, 0.009, and 0.001, respectively) compared with the B group. No significant differences were observed in opioid consumption, postoperative adverse events, length of postoperative hospitalization, and postoperative inflammatory factors at 72 h between the groups. The blood concentrations of bupivacaine in both groups did not exceed the toxicity threshold at 72 h postoperatively. CONCLUSION: The use of liposomal bupivacaine for ultrasound-guided RLB in PLIF patients did not reduce perioperative opioid consumption compared to bupivacaine. Howerve, liposomal bupivacaine did not increase complication rates and prolonged the duration of nerve block analgesia, which is safe and reliable in the postoperative analgesia in patients undergoing PLIF. TRIAL REGISTRATION: Clinicaltrials.gov. Identifier ChiCTR2400091488, 29 October 2024. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12871-026-03721-2.