Dexmedetomidine-Esketamine Combination and Sleep Disturbances After Major Noncardiac Surgery

Dexmedetomidine 0.4 μg/kg and esketamine 0.2 mg/kg is infused over 10 minutes before anesthesia induction. Dexmedetomidine 0.20 μg/kg/h and esketamine 0.10 mg/kg/h is then infused until 60 minutes before the expected end of surgery. Patient-controlled intravenous analgesia is established with 100 μg dexmedetomidine, 50 mg esketamine, and 100 μg sufentanil, diluted to 100 mL with normal saline, and programmed to deliver 2-mL boluses with a lock-out interval of 8 minutes and background infusion rate at 1 mL/h for up to 72 hours after surgery.

Placebo (normal saline) is administered in the same rate and volume as that in the dexmedetomidine-esketamine group. Patient-controlled intravenous analgesia is established with 100 μg sufentanil, diluted to 100 mL with normal saline, and programmed to deliver 2-mL boluses with a lock-out interval of 8 minutes and background infusion rate at 1 mL/h for up to 72 hours after surgery.