Objective: To evaluate the effect of dexmedetomidine on post-operative cognitive dysfunction (POCD) and possible action mechanisms.
Methods: A total of 148 aged surgical patients were divided into two groups, which were treated with dexmedetomidine (Dex group) or normal saline (control group) during general anesthesia. The incidence of POCD one day after surgery was evaluated using Mini-Mental State Examination and serum levels of interleukin 6 (IL-6) and tumor necrosis factor α (TNF-α) were measured using ELISA. The correlation between the two cytokines and POCD was evaluated using quartile division assay.
Results: The incidence of POCD was 9.20% and 21.31% in Dex and control groups, respectively. It is significantly different between the two groups (P < 0.05). The levels of IL-6 and TNF-α were significantly increased after surgery, as compared to before surgery (P < 0.05). Compared to control group, Dexmedetomidine significantly inhibited the increase of post-operative IL-6 and TNF-α levels (P < 0.05). The incidence of POCD was significantly different between quartile divisions of IL-6 and TNF-α (P < 0.05). Pearson correlation analysis showed that IL-6 and TNF-α were positively correlated with the POCD (r = 0.689, P = 0.043 and r = 0.711, P = 0.038, respectively).
Conclusions: The results demonstrate that dexmedetomidine reduces the incidence of POCD in aged patients, and inflammation suppression may underlie the action mechanism.
Keywords: Dexmedetomidine; POCD; inflammation; quartile division.