Effects Of Remimazolam At Different Levels Of Sedation On Explicit And Implicit Memory In Patients With Regional Anesthesia

Objective:To assess the effects of different sedation depths of remimazolam on explicit memory(EM)and implicit memory(IM)in patients with regional anesthesia.Methods:A total of 34 patients,19 males and 15 females,BMI 18～30kg/m2,aged 18～55 years with ASA physical status Ⅰ or Ⅱ,were selected from the First Hospital of Shanxi Medical University during January 2022 to February 2022.They underwent elective surgery under regional anaesthesia and were randomly divided into mild sedation group(group M)and deep sedation(group D).Regional anesthesia was performed after enter the operating room,visual analog scale(VAS)score was performed before cuting skin,then to control the BIS index for more than 3 min in the corresponding range during the operation which the initial dose of 0.1mg·kg-1·h-1 was continuously injected with 1mg/ml remimazolam for sedation and the dosage was gradually increased at a gradient of 0.1mg·kg-1·h-1,to controll BIS index in group M and group D for 60～80 and 40～60 respectively,maintained for more than 3 minutes,maintenance dose of remimazolam and Observer’s assessment alert/Sedation(OAAIS)were recorded after that,auditory stimulus was presented during the operation,and OAA/S score was conducted again after auditory stimulus finished.The duration of operation was recorded at the end of the operation,a simple questionnnaire interview was conducted after four to twenty-four hours and time between discontinuation and interview was recorded,then take the memory test and calculated hit ratio,than explicit and implicit memory was assessed by process dissociation procedure extended model.Results:Excluding 4 cases that failed to complete the experimenter due to force majeure,a total of 34 patients were finally included,with 17 cases in each group.None of the patients recalled any of the intraoperative events during a simple questionnaire interview in which EM was initially assessed before the memory test.EM and IM scores in the group M were 0.041(-0.015～0.076)and 0.198(0.043～0.353)respectively.EM and IM scores in the group D were 0.080(0.004～0.151)and 0.062(-0.003～0.114)respectively.The IM score was significantly greater than zero in the group M(P<0.05).Conclnsion:The IM can be eliminated by remimazolam in the deep sedation maintained BIS40-60.