Efficacy of dexmedetomidine as a neuraxial adjuvant for elective cesarean sections: a meta-analysis of randomized trials

Objective: To evaluate the efficacy and safety of dexmedetomidine as a neuraxial adjuvant for elective caesarean section. Methods: We searched the randomized controlled trials (RCTs) assessing the effect of dexmedetomidine as a neuraxial adjuvant in elective caesarean section in PubMed, EMbase, Web of science, EBSCO, and Cochrane library databases. Results: 11 RCTs were included. Overall, compared with control intervention in patients with elective cesarean section, dexmedetomidine intervention could significantly improve the characteristics of the block, including onset of sensory block (MD: -1.31 minutes; 95% CI: -2.68 to -0.06; P < 0.1), onset of motor block (MD: -0.79 minutes; 95% CI: -1.13 to -0.46; P < 0.05), duration of the sensory block (MD: 64.30 minutes; 95% CI: 21.67 to 106.93; P < 0.05) and duration of the motor block (MD: 24.69 minutes; 95% CI: 8.67 to 44.31; P < 0.05). Additionally, when compared with control group dexmedetomidine could prolong time to rescue analgesia (SMD: 3.81; 95% CI: 2.92 to 4.70; P < 0.05) and reduce the fentanyl consumption (RR= 0.20, 95% CI: 0.10-0.38, P < 0.05). The incidence of shivering in the dexmedetomidine group was significantly lower than that in the control group (RR= 0.41, 95% CI: 0.29-0.58, P < 0.05). The incidences of nausea and vomiting, bradycardia, hypotension and pruritus were not different between the two groups. Conclusion: Dexmedetomidine as a neuraxial adjuvant can improve the characteristics of the block, prolong time to rescue analgesia, reduce fentanyl consumption, and decrease the incidence of shivering during elective cesarean section.