Is Depth Of Anesthesia Related To Postoperative Cognitive Dysfunction ?

Objective:Postoperative Cognitive Dysfunction(POCD)is a postoperative complication of the central nervous system,which mainly refers to the dysfunction of orientation,memory,attention,calculation,cognition and sleep in patients with normal mental and cognitive function before operation.Postoperative Cognitive dysfunction may occur at various times,and cognitive impairment occurring within 7 days after operation is called early postoperative cognitive dysfunction,and cognitive dysfunction may also occur in all age groups,especially in the elderly.The purpose of this study is to study the correlation between the monitoring of anesthesia depth and postoperative cognitive dysfunction in order to provide a new perspective for the treatment of postoperative cognitive dysfunction.Methods : Patients who were planned for gastrointestinal laparoscopic surgery in general anesthesia were included between February 2017 and December 2017.A total of 80 patients were divided into two groups.In the BIS group,the anesthesiologist according to the bispectral index to maintain the appropriate depth of anesthesia,while the control group used the screen obscured the bispectral index in monitoring depth of anesthesia,and anesthesiologists unknown values,anesthesiologists according to clinical experience to maintain the depth of anesthesia.Two groups of patients were evaluated before and after 24 hours,first to 7 days afteroperation,first days,3 days,7 days,discharged time,30 days,180 days,postoperative cognitive dysfunction and postoperative delirium were recorded.The scale of Mini-mental State Examination(MMSE)and the scale of Confusion Assessment Method(CAM)was used for assessment.the score of Mini-mental State Examination was more than 2 points before the operation,that is,the postoperative cognitive impairment was considered;postoperative delirium was considered when the scale of Confusion Assessment Method was more than 22 points.Results: 74 people were included in the experiment,39 in the BIS group and 35 in the control group.There was no significant difference in age,sex,height,weight and so on between the two groups before operation.BIS monitoring did not alter the incidence of postoperative delirium in the BIS group cpmpared with the control group in first to 7 days after surgery.And the incidence of postoperative delirium in the two groups was low.The incidence of postoperative cognitive dysfunction in two groups of patients after first days,3 days,7 days,discharge time and postoperative 30 days after surgery,were no significant difference.Although there was no significant difference between the two groups,the overall incidence of cognitive impairment was higher in the control group except the first day after the operation.There was no significant difference in the intraoperative condition,postoperative hospitalization time and intraoperative anesthetic dose between the two groups.However,there was a significant difference in the incidence of postoperative cognitive dysfunction between two groups of patients 180 th daysafter operation(P=0.026<0.05).The incidence of POCD in group BIS was7.7%(3/39),While the incidence of POCD in control group was 27.3%(9/33,there were 2 missing patients).In addition,the incidence of cognitive impairment in the patients over 60 years old accounted for a large proportion of the population,and the incidence of cognitive dysfunction after 180 days after operation was 18.2%.There was also a significant difference in satisfaction between the two groups(P=0.039 < 0.05),and the satisfaction of BIS group was higher.Conclusion: It is confirmed that the incidence of postoperative cognitive dysfunction is high,especially in elderly patients.The use of BIS to monitor the depth of anesthesia can effectively reduce the incidence of postoperative cognitive dysfunction after 180 days after surgery,and increase the satisfaction of the patients with anesthesia.