Sedative effect of dexmedetomidine during regional anesthesia:a randomized,double-blinded,controlled trial

Objective: To evaluate the efficacy and safety of dexmedetomidine during regional anesthesia.Methods: Patients undergoing regional anesthesia(n=60) were randomly assigned to dexmedetomidine(n=30) or fentanyl plus midazolam group(control,n=30).In all the patients,the medicines were intravenously administrated for 10min.Blood pressure(BP),heart rate(HR),respiratory rate(RR),oxygen saturation(SpO2) and OAA/S(Observer's Assessment of Alertness-Sedation) scale were evaluated at time-points of before(baseline) and 5min(T1),8min(T2),10min(T3),12min(T4),15min(T5),20min(T6),25min(T7),30min(T8) and 40min(T9) after the treatment.The side effects in patients of the two groups were also recorded.Results: In dexmedetomidine group,compared with the baseline parameters,systolic blood pressure(SBP) and diastolic blood pressure(DBP) decreased at T4～T7,HR decreased at T3～T7,and OAA/S decreased at T4～T7.In control group,compared with the baseline parameters,SBP decreased at T3,and OAA/S decreased at T4 and T5(P0.05 or P0.01).In dexmedetomidine group,compared with control group,SBP decreased at T5～T7,DBP decreased at T6 and T7,HR decreased at T4～T6,and OAA/S decreased at T5～T7.The incidences of respiratory inhibition,nausea and vomiting were significantly reduced in dexmedetomidine group(P0.05 or P0.01).There were no significant differences in RR and SpO2 between 2 groups(P0.05).Conclusion: Dexmedetomidine can provide a good sedation with low side effects.It is safe and effective for the patients undergoing regional anesthesia.