Effect of Dexmedetomidine Dose on Reducing Delirium in Adults: An Indirect Comparison of Controlled Trials.

BACKGROUND Postoperative delirium affects recovery. Dexmedetomidine shows promise in reducing it, but the ideal dose is unclear. MATERIAL AND METHODS We performed a systematic review of randomized controlled trials and meta-analyses. Studies from PubMed, Embase, Web of Science, and the Cochrane Library were retrieved. Only trials involving adults (≥18 years) were considered. The effectiveness of high (loading dose, >0.5 µg/kg) and low doses (loading dose, ≤0.5 µg/kg) of dexmedetomidine in preventing delirium was examined, along with the incidence of delirium and adverse events like hypotension and bradycardia. RESULTS High-dose dexmedetomidine was associated with a lower delirium incidence compared to low-dose. The incidence of bradycardia or hypotension did not differ significantly between the 2 groups. However, some included studies had small sample sizes, focused on intraoperative use, or had potential data bias and heterogeneity in the low-dose group. CONCLUSIONS High-dose dexmedetomidine may be more effective in reducing postoperative delirium without increasing the risk of bradycardia or hypotension. But due to study limitations, more randomized controlled trials are required to confirm these findings.