To systematically evaluate the efficacy of dexmedetomidine in elderly patients undergoing cardiac surgery.

Clinical controlled trials in PubMed, Embase, Ovid, Web of Science, CNKI, Wanfang database and VIP database were retrieved. Two researchers independently extracted data and evaluated the quality of the included literature. A meta-analysis was performed on the extracted data by RevMan 5.3.

A total of 2 072 patients in 10 studies were included. The results of the meta-analysis showed that the incidence of postoperative delirium and the operative mortality in dexmedetomidine group were significantly lower than that in control group (RR=0.77, 0.40; 95%CI: 0.63-0.95, 0.17-0.91; Z=2.46, 2.18; P < 0.05), and the postoperative mechanical ventilation time was shorter than that in control group (WMD=-2.07, 95%CI:-2.73--1.41, Z=6.13, P < 0.01). However, there were no significant differences in postoperative ICU stay, postoperative hypotension and postoperative bradycardia between the two groups (P > 0.05).

Dexmedetomidine can reduce the incidence of postoperative delirium, postoperative mortality and mechanical ventilation time in elderly cardiac surgery patients, but has no significant effect on postoperative ICU stay, incidence of postoperative hypotension, and postoperative bradycardia.