Dexmedetomidine versus fentanyl as adjuvants to ropivacaine for epidural anaesthesia: A systematic review and meta-analysis

Background Several randomized controlled trials (RCTs) have evaluated the use of dexmedetomidine versus fentanyl as adjuvants to ropivacaine for epidural anaesthesia, yet the results are conflicting. We aimed to conduct this meta-analysis to assess the effects and safety of dexmedetomidine and fentanyl as adjuvants to ropivacaine for epidural anaesthesia. Methods Cochrane Library et al databases were searched from inception to Jan 28, 2020. The synthesised effect sizes were presented as mean difference (MD) or odd of risk (OR) and 95% confidence intervals (95% CI). Results Nine RCTs with a total of 672 patients were included. The synthesised results indicated that the mean time to the onset of sensory block (MD: -2.82, 95% CI (-4.84, -0.80)), and the time to maximum motor block (MD: -4.35, 95% CI (-7.31, -1.40)) in dexmedetomidine group was significantly less than that of fentanyl group, while the mean time to rescue analgesia in dexmedetomidine group was significantly increased (MD: 99.13, 95% CI (82.89, 115.37)). The incidence of nausea and vomiting (OR: 0.43, 95% CI (0.29, 0.66)), and shivering (OR: 0.34, 95% CI (0.18, 0.63)) in dexmedetomidine group was significantly reduced, yet the incidence of oral dryness in dexmedetomidine group was significantly increased OR: 5.31, 95% CI (1.69, 16.69)). Conclusions Dexmedetomidine is better than fentanyl as adjuvant to ropivacaine for epidural anaesthesia with better effects and less adverse events.