Impact of Preoperative Quadratus Lumborum Block on Postoperative Opioid Consumption After Laparoscopic Hysterectomy

Context: (Background) Given the opioid epidemic, gynecologic enhanced recovery after surgery (ERAS) pathways have been developed to reduce post-operative narcotic use through multimodal pain regimens and pre-surgical anesthetic adjuncts. While local anesthetic injection at trocar incision sites has long been accepted as a standard practice to decrease postoperative pain in laparoscopic surgery, including hysterectomy, regional nerve blockades are emerging as a promising adjunct technique for management of perioperative pain. At this time, the data evaluating the effect of regional nerve blocks on postoperative pain after laparoscopic hysterectomy are limited, thus the investigators designed the following study.

Objectives: (primary and secondary objectives) To determine the impact of preoperative quadratus lumborum (QL) block on postoperative pain following laparoscopic hysterectomy. The primary outcomes will be intraoperative and immediate post-operative opioid use, measured in morphine equivalent dose (MED). Secondary outcomes will include pain scores, functional impact of pain, perception of pain and recovery, voiding dysfunction, time to discharge, nausea/vomiting, emergency room visits, readmission, and reoperation rates.

Study Design:

This study is designed as a prospective, double-blinded, randomized controlled trial comparing opioid use in women undergoing laparoscopic hysterectomy who receive a preoperative QL block to local injection of bupivacaine (common local anesthestic).

Setting/Participants:

The study will take place at a single academic medical center that is a referral center within the military health system. Eligible patients will include adult women undergoing laparoscopic hysterectomy, including robot-assisted, that are not pain management clinic patients and don't use opioids preoperatively. Patients who have contraindications to the study protocol will be ineligible. A total of 76 patients will be enrolled with 38 in each arm.

Study Interventions and Measures:

Study arm patients will receive a preoperative bilateral QL block with an admixture of liposomal bupivacaine and 0.25% bupivacaine then an intraoperative placebo injection at each incision site with 0.9% saline. Control arm patients will receive a preoperative bilateral placebo QL block with 0.9% saline then an intraoperative injection of 0.25% bupivacaine at each incision site. Pre, intra, and postoperative care will be standardized for all study patients using the Gynecologic ERAS protocol and standard hospital perioperative procedures/protocols.

Opioid use will be measured in morphine equivalent doses (MEDs) at the intraoperative and immediate postoperative (prior to discharge) timepoints, as well as, at postoperative days 1, 3, 5, 14, and 4-6 weeks. Pain scores and impact of pain on functional status will be assessed using the DVPRS and Quality of Recovery-15 survey at these timepoints.

• Opioid use after discharge [Time frame: From discharge from the hospital to the 4-6 week post-operative appointment.]
• Pain scores during inpatient post-operative care [Time frame: From time of arrival in the PACU to time of discharge from the hospital. Anticipated to be the same day, about 4-6 hours post-operative. Will be assessed up to 24 hours after surgery if the patient remains admitted.]
• Time to PACU discharge [Time frame: From time of arrival in the PACU to time of transfer to the second phase of post-operative care. Anticipated to be about 1-3 hours post-operative. Will be assessed up to 12 hours after surgery if the patient remains in the PACU.]
• Voiding dysfunction [Time frame: From time of arrival in the PACU to time of discharge from the hospital. Anticipated to be the same day, about 4-6 hours post-operative. Will be assessed up to 24 hours after surgery if the patient remains admitted.]
• Pain scores after discharge [Time frame: From discharge from the hospital to the 4-6 week post-operative appointment.]
• Quality of Recovery-15 scores after discharge [Time frame: From discharge from the hospital to the 4-6 week post-operative appointment.]