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

BACKGROUND

Dexmedetomidine plays a pivotal role in mitigating postoperative delirium and cognitive dysfunction while enhancing the overall quality of life among surgical patients. Nevertheless, the influence of dexmedetomidine on such complications in various anaesthesia techniques remains inadequately explored. As such, in the present study, a meta-analysis was conducted to comprehensively evaluate its effects on postoperative delirium and cognitive dysfunction.

METHODS

A number of databases were searched for randomised controlled trials comparing intravenous dexmedetomidine to other interventions in preventing postoperative delirium and cognitive dysfunction in non-cardiac and non-neurosurgical patients. These databases included PubMed, Embase, and Cochrane Library. Statistical analysis and graphing were performed using Review Manager, STATA, the second version of the Cochrane risk-of-bias tool for randomised controlled trials, and GRADE profiler.

MAIN RESULTS

This meta-analysis comprised a total of 24 randomised controlled trials, including 20 trials assessing postoperative delirium and 6 trials assessing postoperative cognitive dysfunction. Across these 24 studies, a statistically significant positive association was observed between intravenous administration of dexmedetomidine and a reduced incidence of postoperative delirium (RR: 0.55; 95% CI 0.47 to 0.64, p < 0.00001, I2 = 2%) and postoperative cognitive dysfunction (RR: 0.60; 95% CI 0.38 to 0.96, p = 0.03, I2 = 60%). Subgroup analysis did not reveal a significant difference in the incidence of postoperative delirium between the general anaesthesia and non-general anaesthesia groups, but a significant difference was observed in the incidence of postoperative cognitive dysfunction. Nonetheless, when the data were pooled, it was evident that the utilisation of dexmedetomidine was associated with an increased incidence of hypotension (RR: 1.42; 95% CI 1.08 to 1.86, p = 0.01, I2 = 0%) and bradycardia (RR: 1.66; 95% CI 1.23 to 2.26, p = 0.001, I2 = 0%) compared with other interventions. However, there was no significantly higher occurrence of hypertension in the DEX groups (RR = 1.35, 95% CI 0.81-2.24, p = 0.25, I2 = 0%).

CONCLUSION

Compared with other interventions, intravenous dexmedetomidine infusion during non-cardiac and non-neurosurgical procedures may significantly reduce the risk of postoperative delirium and cognitive dysfunction. The results of subgroup analysis reveal a consistent preventive effect on postoperative delirium in both general and non-general anaesthesia groups. Meanwhile, continuous infusion during general anaesthesia was more effective in reducing the risk of cognitive dysfunction. Despite such findings, hypotension and bradycardia were more frequent in patients who received dexmedetomidine during surgery.

The role of dexmedetomidine administered via intravenous infusion as adjunctive therapy to mitigate postoperative delirium and postoperative cognitive dysfunction in elderly patients undergoing regional anesthesia: a meta-analysis of randomized controlled trials

STUDY OBJECTIVE

This meta-analysis aimed to assess whether continuous intravenous administration of DEX during surgery can be part of the measures to prevent the onset of postoperative delirium and postoperative cognitive dysfunction in elderly individuals following regional anesthesia.

METHODS

We searched the databases of PubMed, Embase, the Cochrane Library and China National Knowledge Infrastructure (by June 1, 2023) for all available randomized controlled trials assessing whether intravenous application of dexmedetomidine can help with postoperative delirium and postoperative cognitive dysfunction in the elderly with regional anesthesia. Subsequently, we carried out statistical analysis and graphing using Review Manager software (RevMan version 5.4.1) and STATA software (Version 12.0).

MAIN RESULTS

Within the scope of this meta-analysis, a total of 18 randomized controlled trials were included. Among them, 10 trials aimed to assess the incidence of postoperative delirium as the primary outcome, while the primary focus of the other 8 trials was on the incidence of postoperative cognitive dysfunction. The collective evidence from these 10 studies consistently supports a positive relationship between the intravenous administration of dexmedetomidine and a decreased risk of postoperative delirium (RR: 0.48; 95%CI: 0.37 to 0.63, p < 0.00001, I2 = 0%). The 8 literature articles and experiments evaluating postoperative cognitive dysfunction showed that continuous intravenous infusion of dexmedetomidine during the entire surgical procedure exhibited a positive preventive effect on cognitive dysfunction among the elderly population with no obvious heterogeneity (RR: 0.35; 95%CI: 0.25 to 0.49,p < 0.00001, I2 = 0%).

CONCLUSION

Administering dexmedetomidine intravenously during surgery can potentially play a significant role in preventing postoperative delirium and postoperative cognitive dysfunction in patients older than 60 years with regional anesthesia according to this meta-analysis.