Effectiveness of dexmedetomidine on postoperative cognitive dysfunction in elderly patients with fracture: A systematic review

Background:Previous studies have explored the effectiveness of dexmedetomidine on postoperative cognitive dysfunction (POCD) in elderly patients with fracture. However, no systematic review has addressed this issue. Thus, this systematic review investigated the effectiveness of dexmedetomidine on POCD in elderly patients with fracture. Methods:In this study, we searched electronic databases of PubMed, EMBASE, Cochrane Library, China National Knowledge Infrastructure, Wang Fang and China Science and Technology Journal Database from their initiation to July 1, 2022. We considered randomized controlled trials of dexmedetomidine on POCD in elderly patients with fracture in this study. Primary outcome was measured by mini-mental state examination. Secondary outcomes were measured by total occurrence rate of postoperative cognitive dysfunction, occurrence rate of delirium, visual analogue scale and occurrence rate of adverse events. Results:A total of 10 studies involving 969 elderly patients with fracture are included in this study. Meta-analysis results showed that there were significant differences on mini-mental state examination at 1-day post-surgery [mean difference (MD) = 2.17; random 95% confidence interval (CI), 1.06, 3.28; P I-2=98%], 3-day post-surgery (MD = 2.70; random 95% CI, 1.51, 3.89; P I-2=98%), and 7-day post-surgery (MD = 1.21; random 95% CI, 0.50, 1.93; P I-2=86%), total occurrence rate of postoperative cognitive dysfunction (odds ratio [OR] = 0.26; fixed 95% CI, 0.11, 0.60; P = .002; I-2= 0%), occurrence rate of delirium (OR = 0.29; fixed 95% CI, 0.11, 0.78; P = .01; I-2= 0%), visual analogue scale (MD = -1.23; random 95% CI, -1.74, -0.72; P I-2=95%), and occurrence rate of adverse events (OR = 0.32; fixed 95% CI, 0.20, 0.50; P I-2= 0%) between the 2 groups. Conclusion:The results of this study showed that dexmedetomidine could effectively manage POCD in elderly patients with fracture. However, the overall quality of included trials is not too high. Thus, the present findings should be cautiously referred.