Preemptive Analgesia Of Dexmedetomidine Reduces Per-operation Pain

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 \[Pain numeric rating scale was assessed with the (Numeric Rating Scale, p-NRS)\].