Effect of ultrasound-guided quadratus lumborum block with dexmedetomidine as an adjuvant on postoperative analgesia for gynecological laparoscopic surgery: a randomized controlled trial

To evaluate and compare the postoperative analgesic efficacy and safety of ultrasound-guided quadratus lumborum block using ropivacaine alone or ropivacaine supplemented with dexmedetomidine in patients undergoing elective gynecological laparoscopic surgery. We conducted a randomized controlled trial at a tertiary hospital in China, between April 5 and December 23, 2024. Adult females undergoing gynecological laparoscopic surgery were randomly assigned to two groups. Following surgery, both groups received an ultrasound-guided posterior quadratus lumborum block; the control group (R) received ropivacaine, while the experimental group (RD) received ropivacaine combined with dexmedetomidine. Data collected included patient demographics, surgical details, consumption of rescue analgesics, Numerical Rating Scale (NRS) scores for incisional and visceral pain at rest and during movement at multiple time points, recovery outcomes, and adverse reactions. The RD group required less rescue analgesia: total morphine consumption was 14.00 [12.00, 15.50] mg vs. 21.00 [14.00, 28.00] mg in Group R (P < 0.01); patient-controlled analgesia demands were also reduced (0.00 [0.00, 1.75] vs. 3.00 [1.00, 5.50] presses, P < 0.01); and required significantly less postoperative intravenous rescue morphine (0.0 [0.0, 0.0] mg vs. 2.5 [0.0, 5.0] mg, P < 0.01). Additionally, at most postoperative time points, the RD group had significantly lower NRS scores for incisional and visceral pain at rest and during movement (P < 0.05). No significant differences were observed in postoperative recovery or adverse events. In patients undergoing gynecologic laparoscopic surgery, ultrasound-guided quadratus lumborum block with ropivacaine combined with dexmedetomidine was significantly associated with a reduction in early postoperative opioid consumption, improved analgesia-related indicators, and no significant increase in adverse reactions. chictr.org.cn/index.aspx(ChiCTR2400082539; April 1st, 2024).