Laparoscopic administration of bupivacaine at the uterosacral ligaments during benign laparoscopic and robotic hysterectomy: a randomized controlled trial

BACKGROUND: Postoperative pain continues to be an undermanaged part of the surgical experience. Multimodal analgesia has been adopted in response to the opioid epidemic, but opioid prescribing practices remain high after minimally invasive hysterectomy. Novel adjuvant opioid-sparing analgesia to optimize acute postoperative pain control is crucial in pre-venting chronic pain and minimizing opioid usage.OBJECTIVE: This study aimed to determine the effect of direct laparo-scopic uterosacral bupivacaine administration on opioid usage and post-operative pain in patients undergoing benign minimally invasive (laparoscopic and robotic) hysterectomy.STUDY DESIGN: This was a single-blinded, triple-arm, randomized controlled trial at an academic medical center between March 15, 2021, and April 8, 2022. The inclusion criteria were patients aged >18 years undergoing benign laparoscopic or robotic hysterectomy. The exclusion criteria were noneEnglish-speaking patients, patients with an allergy to bupivacaine or actively using opioid medications, patients undergoing transversus abdominis plane block, and patients under-going supracervical hysterectomy or combination cases with other surgical services. Patients were randomized in a 1:1:1 fashion to the following uterosacral administration before colpotomy: no adminis-tration, 20 mL of normal saline, or 20 mL of 0.25% bupivacaine. All patients received incisional infiltration with 10 mL of 0.25% bupiva-caine. The primary outcome was 24-hour oral morphine equivalent usage (postoperative day 0 and postoperative day 1). The secondary outcomes were total oral morphine equivalent usage in 7 days, last day of oral morphine equivalent usage, numeric pain scores from the universal pain assessment tool, and return of bowel function. Patients reported postoperative pain scores, total opioid consumption, and re-turn of bowel function via Qualtrics surveys. Patient and surgical characteristics and primary and secondary outcomes were compared using chi-square analysis and 1-way analysis of variance. Multiple linear regression was used to identify predictors of opioid use in the first 24 hours after surgery and total opioid use in the 7 days after surgery.RESULTS: Of 518 hysterectomies screened, 410 (79%) were eligible, 215 (52%) agreed to participate, and 180 were ultimately included in the final analysis after accounting for dropout. Most hysterectomies (70%) were performed laparoscopically, and the remainder were performed robotically. Most hysterectomies (94%) were outpatient. Patients ran-domized to bupivacaine had higher rates of former and current tobacco use, and patients randomized to the no-administration group had higher rates of previous surgery. There was no difference in first 24-hour oral morphine equivalent use among the groups (P1/4.10). Moreover, there was no difference in numeric pain scores (although a trend toward significance in discharge pain scores in the bupivacaine group), total 7-day oral morphine equivalent use, day of last opioid use, or return of bowel function among the groups (P>.05 for all). The predictors of increased 24-hour opioid usage among all patients included only increased postanesthesia care unit oral morphine equivalent usage. The predictors of 7-day opioid usage among all patients included concurrent tobacco use and mood disorder, history of previous laparoscopy, estimated blood loss of >200 mL, and increased oral morphine equivalent usage in the postanesthesia care unit. CONCLUSION: Laparoscopic uterosacral administration of bupiva-caine at the time of minimally invasive hysterectomy did not result in decreased opioid usage or change in numeric pain scores.