Effectiveness of Liposomal Bupivacaine With Bupivacaine Hydrochloride vs Bupivacaine Hydrochloride Alone as a Local Anesthetic for Children Undergoing Ambulatory Urologic Surgery: The Baby ORIOLES Randomized Clinical Trial.

We sought to determine if the addition of liposomal bupivacaine to bupivacaine hydrochloride improves opioid-free rate and postoperative pain scores among children undergoing ambulatory urologic surgery. A prospective, phase 3, single-blinded, single-center randomized trial with superiority design was conducted in children 6 to 18 years undergoing ambulatory urologic procedures between October 2021 and April 2023. Patients were randomized 1:1 to receive dorsal penile nerve block (penile procedures) or incisional infiltration with spermatic cord block (inguinal/scrotal procedures) with weight-based liposomal bupivacaine plus bupivacaine hydrochloride or bupivacaine hydrochloride alone. The primary outcome was opioid-free rate at 48 hours. Secondary outcomes included parents' postoperative pain measure scores, numerical pain scale scores, and weight-based opioid utilization at 48 hours and 10 to 14 days. We randomized 104 participants, with > 98% (102/104) with complete follow-up data at 48 hours and 10 to 14 days. At interim analysis, there was no significant difference in opioid-free rate at 48 hours between arms (60% in the intervention vs 62% in the control group; estimated difference in proportion -1.9% [95% CI, -20%-16%]; The addition of liposomal bupivacaine to bupivacaine hydrochloride did not significantly improve opioid-sparing effect or postoperative pain compared with bupivacaine hydrochloride alone among children ≥ 6 years undergoing ambulatory urologic surgery.