BACKGROUND: Some studies have revealed that intravenous dexmedetomidine and esketamine improve the quality of sleep after surgery. The investigators investigated whether co-administration dexmedetomidine and esketamine could better improve the the quality of sleep after modified radical mastectomy.

METHODS: One hundred and five women with elective modified radical mastectomy were randomly divided into 3 groups: Patients in group D received dexmedetomidine (0.5 µg/kg over 10 min before the induction of anesthesia), and then dexmedetomidine was infused at a rate of 0.4 μg/kg/h until 20 min before the end of operation. Patients in group DE1 received a bolus infusion of dexmedetomidine (0.5 µg/kg) and esketamine (0.5 mg/kg)over 10 min before the induction of anesthesia, and then dexmedetomidine were infused at a rate of 0.4 µg/kg/h and 2 µg/kg/min until 20 min before the end of operation, respectively. Patients in group DE2 received received a bolus infusion of dexmedetomidine (0.5 µg/kg) and esketamine (0.5 mg/kg)over 10 min before the induction of anesthesia, and then dexmedetomidine were infused at a rate of 0.4 µg/kg/h and 4 µg/kg/min until 20 min before the end of operation, respectively. Primary outcome was the quality of sleep (PSQI) at the day after surgery and 1 day after surgery. The secondary outcomes included MAP, HR, postoperative VAS pain scores, side effects such as the incidence of postoperative nausea and vomiting, hallucination, as well as agitation, drowness, postoperative rescue analgesics and anti-emetics, recovery time, and extubation time.

Inclusion Criteria:

• American Society of Anesthesiologists (ASA) physical status Ⅰ- Ⅱ
• Scheduled for elective modified radical mastectomy

Exclusion Criteria:

• Severe respiratory disease
• Renal or hepatic insufficiency
• History of preoperative psychiatric
• Preoperative bradycardia
• Preoperative atrioventricular block
• Preoperative hypertension
• BMI>30