Effects of dexmedetomidine on perioperative stress, inflammation, and immune function: systematic review and meta-analysis

Background: Dexmedetomidine (DEX) is a highly selective alpha2 adrenoceptor agonist with broad pharmacological effects, including sedation, analgesia, anxiolysis, and sympathetic tone inhibition. Here we report a systematic review and meta-analysis of its effects on stress, inflammation, and immunity in surgical patients during the perioperative period. Methods: We searched MEDLINE, METSTR, Embase, and Web of Science for clinical studies or trials to analyse the effects of DEX on perioperative stress, inflammation, and immune function. Results: Sixty-seven studies (including randomised controlled trials and eight cohort studies) with 4842 patients were assessed, of which 2454 patients were in DEX groups and 2388 patients were in control (without DEX) groups. DEX infusion during the perioperative period inhibited release of epinephrine, norepinephrine, and cortisol; decreased blood glucose, interleukin (IL)-6, tumour necrosis factor-alpha, and C-reactive protein; and increased interleukin-10 in surgical patients. In addition, the numbers of natural killer cells, B cells, and CD4(+) T cells, and the ratios of CD4(+):CD8(+) and Th1:Th2 were significantly increased; CD8(+) T-cells were decreased in the DEX group when compared with the control group. Conclusions: DEX, an anaesthesia adjuvant, can attenuate perioperative stress and inflammation, and protect the immune function of surgical patients, all of which may contribute to decreased postoperative complications and improved clinical outcomes.