Clinical trials

Objective: To investigate the temporal dynamics of dexmedetomidine's analgesic effects in the brain using EEG. Methods: Eligible patients scheduled for total hip arthroplasty under intrathecal anesthesia received a continuous infusion of DEX at 1.5 μg/(kg·h) for 15 minutes before neuraxial puncture, followed by an additional 15-minute infusion. The study was divided into three phases: Phase 1: Non-dosing phase (Baseline). Phase 2: DEX preemptive analgesia phase (DEX infusion). Phase 3: DEX cessation phase (Post-infusion). Outcomes: Primary safety outcome: EEG spectral analysis at different phases. Secondary outcomes: NRS scores, postoperative nausea and vomiting (PONV), dizziness, agitation, and time to intestinal exhaust within 48 hours. Intraoperative hemodynamics were also monitored.

Background:Preemptive analgesia is the initiation of analgesic regimen before the onset of nociceptive stimulation, preventing the amplification of pain due to peripheral and central sensitization and thereby reducing subsequent pain. Preemptive analgesia of dexmedetomidine (DEX) in the epidural and subarachnoid space can effectively prevent the central sensitization, and significantly reduce the phantom limb pain, residual pain after one year of lower limb amputation. Objective: To investigate the per-operative effects of DEX preemptive analgesia. Method:The patients scheduled noncardiac surgery undergoing general anesthesia were selected and divided into DEX group and Placebo group randmized. The DEX group was continuously pumped at 1.5 μg /(kg·h) for 15 minutes before induction, and 15min after induction. The Placebo group was infused with equal amounts of normal saline.The Coprimary efficacy outcome was a composite of analgesia effect, one is the Compliance Rate of IOC2 target in intra-operation, another is the the rate of none-to-slight post-operative pain assessed with the p-NRS≦3 at 12 hours after surgery \[Pain numeric rating scale was assessed with the (Numeric Rating Scale, p-NRS)\].

1. Sufentanil as an strong analgesic is used widespreadly during laparoscopic cholecystectomy. 2. Lower dosages of sufentanil facilitated with dexmedetomidine can offer enough analgesia effect. 3. The investigator are planning use the most classical method for determining the ED50 or half effective concentration of sufentanil facilitated with dexmedetomidine using sequential method, which is also called" up and down method" and" ladder method".