Influence of dexmedetomidine on postoperative cognitive dysfunction in the elderly: A meta‐analysis of randomized controlled trials

Abstract

Introduction Dexmedetomidine (Dex) is suggested to be neuroprotective. However, influence of Dex on postoperative cognitive dysfunction (POCD) in the elderly remains unknown. Methods We performed a meta‐analysis of randomized controlled trials (RCTs) to evaluate the effect of Dex on POCD. Relevant studies were obtained by search of PubMed, Embase, and Cochrane's Library databases. A random‐effect model was used to pool the results. Results Fourteen RCTs including 1626 adults of 60 years or older who received surgery with general anesthesia were included. Because methodologically diverse scales were used for POCD, eight RCTs with POCD diagnosed with Mini‐Mental State Examination (MMSE) were included in the meta‐analysis, while the remaining six RCTs with POCD diagnosed with other scales were qualitative synthesized. Pooled results of RCTs with MMSE showed that Dex significantly reduced the incidence of POCD (risk ratio: 0.47, 95% confidence interval: 0.37–0.60, p < 0.001) with no significant heterogeneity (I2 = 0%) or publication bias (p for Egger's regression test = 0.579). For the remaining six RCTs with POCD diagnosed with other scales, three of them showed that Dex was associated with a significantly lower incidence of POCD, while the other three RCTs did not show a significant difference. Conclusions Dex is associated with a reduced risk of POCD in elderly patients receiving surgeries with general anesthesia, and the results were mainly obtained in studies with POCD diagnosed with MMSE. Based on these findings, Dex may be considered as a preventative measure for POCD in elderly patients.

Dexmedetomidine alleviates hippocampal neuronal loss and cognitive decline in rats undergoing open surgery under sevoflurane anaesthesia by suppressing CCAAT/enhancer‐binding protein beta

“…Perioperative administration of Dex also significantly improves early postoperative cognitive function in children undergoing tonsillectomy (Peng et al, 2021). Studies have found that Dex injection during laparoscopic cholecystectomy reduces serum proinflammatory cytokines and the occurrence of POCD (Wu et al, 2022; Yu et al, 2022). Dex was shown to reduce the severity of neuroinflammation and neuronal apoptosis in animal models of systemic inflammatory response syndrome (SIRS) and surgical injury (Du et al, 2021; Wang et al, 2020).…”

Correlation between neutrophil/lymphocyte ratio, platelet/lymphocyte ratio and postoperative cognitive dysfunction in elderly patients with esophageal cancer

“…[18] Although it has limitations such as learning effect and capping effect, it is easy to be carried out in a short time with high-sensitivity and specificity for the diagnosis of POCD, which has already been widely applied in clinical practice. [19] POCD occurred after surgery with incidence ranging from 17% to 56% and with a tendency to resolve over time from 3% to 34.2%. [20] In the present study, elderly patients with esophageal cancer were included as research objects, and the incidence of POCD detected by MMSE scale revealed to be 23.1%, which was also consistent with previous research results.…”

Intravenous infusion of dexmedetomidine during the surgery to prevent postoperative delirium and postoperative cognitive dysfunction undergoing non-cardiac surgery: A meta- analysis of randomized controlled trials

“…Two meta-analyses published in 2019 [44] and 2022 [45] were conducted to investigate the impact of DEX on postoperative neurocognitive function of elderly patients who underwent non-cardiac surgery. Regarding the elderly patients who had non-cardiac surgery, both studies found that DEX administration during the perioperative period was more effective than other sedatives in maintaining cognitive function after the surgical intervention.…”