Low-dose dexmedetomidine improves postoperative sleep and pain in gynecological surgery: a randomized trial

Background: Postoperative sleep disturbances often lead to a vicious cycle with pain, severely hindering the recovery of patients. Women, due to fluctuations in sex hormones and their unique pain modulation mechanisms, are particularly vulnerable to both postoperative sleep disorders and pain. Dexmedetomidine (DEX) has shown potential in promoting sleep and providing analgesia. Therefore, exploring its application in optimizing postoperative pain management for gynecological patients is of great significance in enhancing recovery outcomes. Objective: This study aimed to assess the impact of adding low-dose dexmedetomidine (DEX) to a sufentanil-based patient-controlled intravenous analgesia (PCIA) regimen on postoperative sleep quality and pain in patients undergoing gynecological surgery. Methods: This single-center, randomized, double-blind, placebo-controlled trial was conducted between 28 September 2025, and 30 November 2025. A total of 130 patients scheduled for elective gynecological surgery were enrolled. Participants were randomly assigned to one of two groups (65 patients per group) using a computer-generated randomization sequence, with allocation concealed via sequentially numbered, opaque sealed envelopes. Patients in the experimental (DS) group received a PCIA) regimen consisting of DEX (0.06 μg/kg/h) combined with sufentanil (0.04 μg/kg/h). The control (S) group received PCIA with sufentanil alone at the same dosage of 0.04 μg/kg/h.The primary outcome was the incidence of sleep disturbance on the first postoperative night, defined as a Pittsburgh Sleep Quality Index (PSQI) global score ≥5. Secondary outcomes included PSQI scores on the first and second postoperative nights, Visual Analogue Scale (VAS) pain scores assessed at 6, 12, 24, and 48 h postoperatively, total postoperative sufentanil consumption, the number of PCA button presses recorded by the infusion pump, and the incidence of adverse events-specifically bradycardia (heart rate