咪达唑仑不同剂量和时机给药的遗忘程度

Extent of Amnesia with Midazolam Different Doses and Timing Administration

目的探讨咪达唑仑遗忘作用的合适给药时机和剂量。方法以240例ASAⅠ级病人对椎管内麻醉穿刺操作的遗忘程度为评价指标,分为椎管内麻醉穿刺操作前(A)组和后(B)组,每组120例;每大组又随机分为4小组,分别给予不同剂量的咪达唑仑,分为0.01mg/kg(M1组)、0.03mg/kg(M2组)、0.1mg/kg(M3组)和生理盐水(NS)组,每组30例。记录用药后的警觉-镇静(OAA/S)评分和手术后1h的遗忘评分(amnesiascore,AS)。结果OAA/S评分:A组和B组中,不同剂量M组与NS组之间,不同OAA/S评分所占人数比例有明显差异;B组中M2与A组中M2相比,OAA/S评分秩次有显著差异,B组中M3组与A组中M3组相比,秩次有显著差异;AS评分:A组中,各剂量M组均有不同程度的遗忘;M2、M3组与M1组间相比,遗忘程度增加,P<0.05;而M2、M3组之间P>0.05;B组中,M1、M2组与NS组遗忘程度相似(P>0.05),而M3组与其余三组相比,遗忘程度明显增加,但其与A组中M3组相比,遗忘程度明显不如后者。结论咪达唑仑的镇静作用同其剂量成正相关;咪达唑仑具有明确的顺行性遗忘作用,并同镇静程度相关,但有封顶效应(ceilingeffect);在较大剂量情况下,亦能产生逆行性遗忘作用,但是效力不及同等剂量下预先给药;这提示咪达唑仑应以适当剂量、在有创操作前给药,可以产生满意的遗忘作用,剂量过大并不能够产生更强的遗忘作用。

Objective To investigate the appropriate timing and dose administration of midazolam that can induce amnesia and it＇ s extent. Methods After ethics committee approval and consent,240 adult female patients undergoing total or sub - total hysterectomy were randomly allocated to 2 groups： before puncture procedure of intravertebral anesthesia （A） and after puncture procedure of intravertebral anesthesia （ B）, 120 patients in each group; Each group was randomly divided into 4 sub - groups ： midazolam O. O1 mg/kg （ ML ） , midazolam O. 03 mg/kg（ ME ） , midazolam O. 1 mg/kg（ M3 ） and normal saline （NS）. 30 patients in each sub -group. OAA/S after Midazolam administration and amnesia score after operation finished in I h were recorded respectively. Results Both group A and group B, there was a dose - dependent deteriortion in OAA/S, sub - group M2 in group B compare with sub - group ME in group A , sub - group M3 in group B compare with sub -group M3 in group A , there was a significant difference in OAA/S （P 〈0.05）respectively. In group A , there was a significant difference in amnesia score （P 〈 0. 05） , but not dose - dependent, there was a significant difference in amnesia score between sub - group M2 and sub-group Ml, sub- group M3 and sub -group Ml respectively, but there was no significant differences between sub -group ME and sub - group M3. In group B, there was no significant differences in amnesia score between sub - group Ml , sub - group ME and normal sa- line, there was a significant difference between sub - group M3 and other sub - group, Particularly, the sub - group M3 in in group B per- formances lighter amnesia than sub - group M3 in in group A （ P 〈 0. 05 ）. Conclusions The sedation of Midazolam showed its dose - dependent. Midazolam can demonstrate anterograde amnesia and correlate with the degree of sedation, but there was a ceiling effect . In larger dosage circumstances, midazolam can also produce retrograde amnesia, but the extent of amnesia induce by same dose lighter than pretreatment. This suggests that we should administer midazolam before invasive operation with appropriate dose. Administration of midazolam before invasive operation could have satisfied amnesia. There is no stronger amnesia effect when adminiser of overdose midazolam.