Effect Of Depth Of Anesthesia On Postoperative Delirium:A Meta-analysis

Background:China’s population aging is in a stage of rapid development.,Aging has become the current situation of the world’s population development,not only China,and the trend of aging will be more obvious in the future.Postoperative delirium(POD)will greatly increase the risk of postoperative complications in the elderly,and prolong hospital stay and increase medical expenses.According to the US survey,the annual cost of a series of medical problems caused by POD can reach$164 billion.Surgery and anesthesia are important risk factors for postoperative delirium,but the specific pathogenesis remains unclear.At present,studies have suggested that the prevention rate of postoperative delirium can reach40%.Therefore,it is especially important to prevent and improve the occurrence of postoperative delirium.Objective:The purpose of this meta-analysis was to investigate whether intraoperative anesthesia depth monitoring would reduce postoperative delirium.Methods:PubMed,EMBASE,Web Of Science,Cochrane Library,CBM,and Wanfang database were searched.From the establishment of the library to February 2019,randomized controlled trials of depth of anesthesia and postoperative delirium were performed,according to inclusion criteria and exclusion criteria.Literature screening and extraction of data.Main outcome measures:Postoperative delirium incidence,secondary indicators were postoperative hospital stay,ICU stay,and mortality.Statistics were analyzed using RevMan5.3 for meta-analysis.Results:Seven randomized controlled trials were included in the analysis,a total of 3907patients,6 interventions were BIS monitoring,and 1 was original EEG monitoring.The whole was divided into two groups,the monitoring group and the control group.After the combined analysis of the seven studies,the difference was statistically significant,but there was a large heterogeneity between the studies(P=0.008,RR:0.70,95%CI:0.54-0.91;I~2=72%);6 BIS Meta-analysis of the study to monitor the depth of anesthesia showed that the difference was statistically significant and non-heterogeneous(P<0.0001,RR:0.67,95%CI:0.57-0.78;I~2=0%),suggesting that the BIS monitoring guided non-deep Anesthesia reduces the incidence of postoperative delirium.Postoperative total mortality analysis showed that the difference was not statistically significant(P=0.16,RR:0.64;95%CI:0.34-1.20;I~2=57%),and the postoperative hospital stay and ICU hospitalization time were heterogeneous.Too big,the analysis cannot explain it.Conclusion:This meta-analysis suggests that BIS-guided non-deep anesthesia can reduce postoperative delirium.More research is needed on the depth monitoring of anesthesia in the original EEG.