Effect of dexmedetomidine as an adjuvant to ropivacaine in stellate ganglion block on postoperative sleep quality in patients undergoing thyroid cancer surgery: a randomized double-blind controlled trial

Abstract

Postoperative sleep disturbance is common after thyroid cancer surgery and may delay recovery. Stellate ganglion block (SGB) can regulate sympathetic activity, but single local anesthetic blockade has limited duration. This trial aimed to evaluate whether perineural addition of dexmedetomidine to ropivacaine in right-sided SGB could improve early postoperative sleep quality among thyroid cancer patients. This randomized, double-blind controlled trial included 60 patients in the per-protocol efficacy analysis ( n = 30 per group); safety and recovery outcomes were assessed in all 62 treated participants. Before anesthesia induction, patients received ultrasound-guided right-sided SGB with a 6-mL injectate: 0.2% ropivacaine alone in group R and 0.2% ropivacaine plus dexmedetomidine 0.5 µg/kg in group RD. Actigraphy assessed sleep on the preoperative night, surgery night (D0), and postoperative nights 1 (D1) and 2 (D2). The retrospectively specified primary endpoint was D1 sleep efficiency (SE). Secondary outcomes included other sleep measures, the Insomnia Severity Index (ISI), Hospital Anxiety and Depression Scale (HADS), resting pain, and rescue analgesia; hemodynamic outcomes were exploratory. On D1, SE was higher in group RD than in group R (88.3 ± 5.8% vs. 81.3 ± 6.7%). The adjusted mean difference was 7.1 percentage points (95% CI 3.8 to 10.3; P < 0.001). In a post hoc Holm-adjusted analysis of the six originally registered sleep outcomes, group × time interactions remained statistically significant for SE, total sleep time (TST), wake after sleep onset (WASO), sleep onset latency (SOL), and ISI, but not for number of awakenings (NA). On D1, group RD also had longer TST (+ 59.4 min; P < 0.01), shorter WASO (− 24.3 min; P < 0.01), and shorter SOL (− 6.5 min; P < 0.001). Among the secondary outcomes, early ISI and HADS score differences favored group RD but were exploratory because standard recall periods overlapped across assessments; their clinical meaning is uncertain. Other secondary findings included lower overall resting pain scores and less rescue analgesic use in group RD. No serious adverse events occurred. The dexmedetomidine–ropivacaine regimen for right-sided SGB was associated with better early postoperative actigraphy-derived sleep outcomes than ropivacaine alone in patients undergoing thyroid cancer surgery. Chinese Clinical Trial Registry, ChiCTR2600118983. Registered 13 February 2026, retrospectively registered.