Perioperative dexmedetomidine administration to prevent delirium in adults after non-cardiac surgery: A systematic review and meta-analysis.

STUDY OBJECTIVE

To evaluate the efficacy of perioperative dexmedetomidine (DEX) administration for preventing delirium in adults after non-cardiac surgery.

DESIGN

Systematic review and meta-analysis of randomized controlled trials (RCTs).

INTERVENTIONS

Perioperative administration of DEX to prevent delirium in adults following non-cardiac surgery.

MEASUREMENTS

The incidence of postoperative delirium (POD).

METHODS

The databases of PubMed, Embase and Cochrane Central Register were searched from inception to Mar 4, 2021 for all available RCTs that assessed DEX for POD in adults after non-cardiac surgery. Risk ratio (RR) with a 95% confidence interval (CI) was calculated for dichotomous data. Standardized mean difference (SMD) was calculated for continuous data. Risk of bias was assessed using the second version of the Cochrane risk-of-bias tool for RCTs (RoB 2.0), and the level of certainty for main outcomes were assessed by the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) methodology.

MAIN RESULTS

Thirteen studies, including the meta-analysis with a total of 4015 patients (DEX group: 2050 patients; placebo group: 1965 patients), showed that DEX significantly reduced the incidence of POD in adults after non-cardiac surgery compared with control group (RR: 0.60; 95%CI: 0.46 to 0.77, P = 0.0001, I = 55%, GRADE = moderate). Meanwhile, there was a statistical difference by the subgroup analysis between the mean age ≥ 65 years group and the mean age<65 years group. There were no statistical differences in length of hospital stay following surgery (SMD: -0.36; 95%CI: -0.80 to 0.07, P = 0.1, I = 97%, GRADE = low) and all-cause mortality rate (RR:0.57; 95%CI: 0.25 to 1.28, P < 0.17, I = 0%, GRADE = moderate) compared with placebo group. However, Meta-analysis showed that DEX administration significantly resulted in intraoperative bradycardia when compared with placebo group (RR: 1.39; 95%CI: 1.14 to 1.69, P = 0.0009, I = 0%, GRADE = high), and as well as intraoperative hypotension (RR: 1.25; 95%CI: 1.11 to 1.42, P = 0.0004, I = 0%, GRADE = high).

CONCLUSION

This systematic review and meta-analysis suggests that perioperative administration of DEX could significantly reduce the incidence of POD in patients elder than 65 years following non-cardiac surgery. However, there was no definite evidence that perioperative DEX could reduce the incidence of POD in patients younger than 65 years of age after non-cardiac surgery. In addition, perioperative DEX administration was associated with an elevated risk of bradycardia and hypotension.