Dexmedetomidine decreases postoperative delirium in the elderly undergoing long-term hepatopancreatobiliary surgery: a randomized controlled trail

Abstract

Objective To determine the effect of dexmedetomidine (Dex) on the postoperative delirium (POD) in elderly patients undergoing long-term hepatopancreatobiliary surgery with general anesthesia. Methods A total of 50 elderly patients who underwent scheduled hepatopancreatobiliary surgery over 4 h were enrolled in this study, and randomly divided into a control group (n=25) and a Dex group (n=25). After induction of anesthesia, a loading dose of Dex at 1 μg/kg was infused for 10 min and then changed to 0.5 μg/(kg·h) for maintenance in the Dex group. The same volume of normal saline was infused in the control group. Mean arterial pressure (MAP) and heart rate (HR) were recorded at the induction of anesthesia (T0), the end of the operation (T1), 5 min after extubation (T2), and 30 min after extubation (T3). Visual analogue score (VAS) and Riker sedation-agitation scale (RSAS) were performed on the patients at T2 and T3. Other data were collected as follows: the extubation time, postanesthesia care unit (PACU) stay time, incidence of emergence delirium, incidence of postoperative nausea and vomiting (PONV), and Aldrete score before leaving the PACU. Blood samples were collected for IL-6 measurements before surgery (Ta) and at 1 h after surgery (Tb). Mini-Mental state examination (MMSE) was completed on the first day after operation, and POD was assessed by the Confusion Assessment Method (CAM) on the first 3 d after operation. The neurological function of the patients was followed up by the electronic medical system and telephone. Results The RSAS scores in the Dex group were lower than those in the control group at T2 and T3 (P<0.05). The VAS score in the Dex group at T3 was lower than that of the control group (P<0.05). Compared with Ta, the IL-6 level in both 2 groups were significantly higher at Tb (P<0.05). At Tb, the level in the Dex group was lower than that in the control group (P<0.05). Compared with the Dex group, the number of patients with emergence delirium or with cognitive dysfunction on the first day after the operation was 3 times and twice, respectively, as in the control group. In both groups, there were no patients with postoperative delirium persists or reoccurrence after initial emergence from anesthesia. Conclusion The intraoperative use of Dex may reduce the emergence delirium after general anesthesia and improve the postoperative neurological function in elderly patients undergoing long-term hepatopancreatobiliary surgery. The mechanism may be associated with the anti-inflammatory effects of Dex.

Keywords

• dexmedetomidine
• aged
• postoperative delirium
• il-6
• long-term operation