Dexmedetomidine as a sedative and analgesic adjuvant in spine surgery: a systematic review and meta-analysis of randomized controlled trials

Purpose This systematic review and meta-analysis appraise the clinical evidence on efficacy and safety of dexmedetomidine (DEX), as a sedative and analgesic adjunct in adult patients undergoing spine surgery. Methods A database search was conducted to identify randomized clinical trials (RCTs) pertinent to the perioperative use of DEX in spine surgery. Sedative and analgesic efficacy of DEX constituted the primary outcomes, whilst the incidence of hemodynamic changes, quality of recovery and occurrence of adverse events served as secondary ones. Results Fifteen studies enrolling a total of 913 patients were selected for qualitative analysis, among which eight RCTs incorporating a placebo comparison group were included in the meta-analysis. Most of the retrieved studies were of moderate to good quality and demonstrated an acceptable risk of bias. DEX-treated patients showed a significant reduction of both propofol [mean difference (MD), -214.47 mg; 95%CI, -253.16 to -175.78; P < 0.001] and morphine equivalents consumption both intraoperatively and postoperatively (MD, -2.69; 95%CI, -3.05 to -2.33; P < 0.001 and MD, -4.36 mg; 95%CI, -6.93 to -1.79; P < 0.001, respectively) compared to those assigned to placebo. Postoperative nausea and vomiting incidence were comparable between DEX and placebo groups, whilst other adverse events were not consistently reported. Conclusions DEX emerges as an attractive alternative to standard sedative and analgesic modalities applied in spine surgery, by attaining a notable sedative and opioid-sparing effect, which goes with an enhanced safety profile. Yet, no definite conclusion can be drawn due to the considerable heterogeneity of available data.