The effect and safety of dexmedetomidine as an adjuvant to local anesthetics in erector spinae plane block: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND: Dexmedetomidine (DEX) has been thought to be an effective adjuvant to local anesthetics (LAs) in erector spinae plane block (ESPB), however, this method of use is not recorded in the drug instructions. Hence, our meta-analysis will evaluate its efficacy and safety for the first time. METHODS: A systematic search of published articles was conducted in the PubMed, Embase, Web of science, and Cochrane Library databases up to July 17, 2022, using specific keywords related to our aims. The time first to request rescue analgesia, number of patient controlled intravenous analgesia (PCIA) presses, rate of rescue analgesia use, postoperative nausea and vomiting (PONV), arrhythmia, and hypotension were calculated by using random-effect models. This systematic review and meta-analysis was registered with PROSPERO (registration number: CRD42022345488). RESULTS: Numerous electronic databases were searched and finally 8 studies with a total of 570 patients, 303 in the DEX arm, 267 in the control arm were included. As an adjuvant to LAs, DEX significantly increased the time to first request of rescue analgesia (mean difference [MD] = 8.40, 95% confidence interval [CI] = 4.70–12.10, P < 0.00001), reduced the number of PCIA presses (MD = -4.12, 95% CI = -7.79 to -0.45, P = 0.03) and the rate of rescue analgesia (odds ratio [OR] = 0.33, 95% CI = 0.17–0.65, P = 0.002). Moreover, the combination reduced the risk of PONV (OR = 0.57, 95% CI = 0.36–0.91, P = 0.02). In addition, there was no difference in the incidence of hypotension (OR = 1.01, 95% CI = 0.37–2.74, P = 0.99) and arrhythmia (OR = 0.76, 95% CI = 0.19–3.07, P = 0.70). CONCLUSION: DEX can reduce analgesic requirements after various surgical procedures when used as an adjuvant to LAs for ESPB. Moreover, there was no significant difference between the two groups in terms of safety indicators (arrhythmia, hypotension). SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12871-023-02019-x.