Effect of preoperative ultrasound-guided stellate ganglion block on pain thresholds and postoperative nausea and vomiting in gynecological laparoscopy: a randomised clinical trial

Despite advancements in laparoscopic techniques, postoperative pain and nausea/vomiting (PONV) remain primary barriers to optimal Enhanced Recovery After Surgery (ERAS) outcomes in gynecology. While stellate ganglion block (SGB) modulates autonomic function, its efficacy in elevating pain thresholds, reducing rescue medication use, and accelerating functional recovery requires robust evidence. This randomized trial evaluated whether preoperative SGB could refine these ERAS metrics. This single-center randomized controlled trial included 84 patients undergoing elective gynecological laparoscopy, who were randomly allocated via computer-generated sequence to receive ultrasound-guided right-sided SGB (5 mL 0.25% ropivacaine at C6) or standard care. Primary endpoints were mechanical pain thresholds (von Frey filaments) and 48-h cumulative PONV incidence; secondary outcomes included VAS pain scores, rescue analgesic/antiemetic requirements, gastrointestinal recovery (time to first flatus/oral intake), and hospital stay. The SGB group exhibited significantly higher mechanical pain thresholds at 24 h (P < 0.001) and a lower 48-h cumulative PONV incidence (24.4% vs. 48.8%, P = 0.036) compared to the Control group. Specifically, PONV incidence was significantly reduced during the 0–6 h, 7–12 h, and 13–24 h intervals (all P < 0.05), with no significant difference observed between 25 and 48 h (P = 0.713). Furthermore, the SGB group required significantly fewer rescue analgesics (31.7% vs. 55.8%, P = 0.026) and antiemetics (17.1% vs. 39.5%, P = 0.023), and achieved faster gastrointestinal recovery (first flatus and oral intake; both P < 0.01). No significant differences were found in 48-h pain thresholds or time to first ambulation (all P > 0.05). Transient Horner’s syndrome occurred in all SGB patients, with no severe complications reported. Preoperative SGB serves as a potent adjunct in gynecological ERAS protocols. By simultaneously elevating pain tolerance and curbing PONV, it facilitates a smoother and faster early recovery phase. Chinese Clinical Trial Registry, ChiCTR2300068430. Registered 18 February 2023, http://www.chictr.org.cn/showproj.aspx?proj=189182.