Effectiveness And Safety Of Dexmedetomidine And Midazolam For Sedation In Adults Under Local Anesthesia Or Regional Block: A Meta-analysis

Objective:Stressful factors in the operating room and during surgery may cause discomfort,anxiety,and restlessness in the awake patient.The purpose of this meta-analysis was to compare the efficacy and safety of dexmedetomidine and midazolam for sedation in adult patients who were undergoing surgery with local or regional anesthesia.Methods: English databases including Pub Med,Embase and Cochrane Library were searched.The time limit for literature search was from the start of the database to December 2020.Researchers will choose a randomized controlled trial that use dexmedetomidine and midazolam for sedation under local anesthesia or regional block in adult patients.Effectiveness indexes of sedation evaluation: The main indexes were Ramsay score,OAA/S score and BIS index.The secondary outcome was the time when the patient’s BIS index reached 70.Safety indicators: residence time of PACU,incidence of hypotension,bradycardia,nausea,vomiting,dizziness,respiratory depression,and shivering.Data were extracted from the final literature and meta-analysis was performed by using Rev Man5.4 software.Results: A total of 12 English articles were included for Meta-analysis,including1006 patients,and there were 505 patients in the dexmedetomidine group and 501 patients in the midazolam group.The results of the meta-analysis showed that there were no statistical significance in Ramsay score between the DEX group and the MID group before injection,and 5,10,15,20 and 60 minutes after the injection.However,the Ramsay score of the DEX group was higher than that of the MID group [MD =0.21,95%CI(0.06,0.37),P = 0.008] when the reference Hong2018 was removed after30 minutes of administration.After 45 minutes of administration,Ramsay score in the DEX group was higher than that in the MID group [MD = 0.35,95%CI(0.19,0.50),P <0.0001].There was no significant difference in OAA / S score and BIS index between the two groups at different administration times(P > 0.05).The time of BIS value reaching 70 in DEX group was shorter than that in MID group [MD =-3.12,95%CI(-5.61,-0.62),P = 0.01].There was no significant difference in the duration of stay between two groups in PACU [MD = 7.65,95%CI(-1.01,16.31),P = 0.08].Compared with MID group,the incidence of hypotension was higher in DEX group [OR =2.60,95%CI(1.34,5.04),P = 0.005].Compared with MID group,the incidence of bradycardia in DEX group was significantly increased [OR = 4.30,95%CI(2.61,7.08),P < 0.00001];There was no statistical significance in the incidence of nausea,vomiting and dizziness between two groups(P > 0.05).The incidence of respiratory depression in the DEX group was lower than that in the MID group [OR =0.51,95%CI(0.29,0.90),P = 0.02].Compared with MID group,the incidence of shivering was significantly lower in DEX group [OR = 0.06,95%CI(0.01,0.48),P =0.008].Conclusion: According to the results of meta-analysis,dexmedetomidine has better sedative effect and higher safety than midazolam in local anesthesia or regional block during adult surgery.