Correlation Between Postoperative Delirium And Preoperative Pain Threshold In Elderly Patients Undergoing Laparoscopic Surgery

Objective:To explore the correlation between postoperative delirium(POD)and preoperative pain threshold in elderly patients undergoing laparoscopic surgery,and explore the feasibility of predicting POD occurrence by preoperative pain threshold measurement.To provide reference for preoperative evaluation for reducing the occurrence and guidance for intervention treatment of POD.Methods:A total of 120 elderly patients with body mass index(BMI)of17-30kg/m~2 and ASA grade II-III were selected for laparoscopic surgery under general anesthesia in the Department of General Surgery of the Second Hospital of Hebei Medical University from August 2020 to January 2021.All patients were evaluated the preoperative cognitive and psychological status 1day before surgery by using Mini-Mental State Examination(MMSE),State-Trait Anxiety Inventory and Self-rating Depression Scale(SDS).Pain Vision was used to measure the pain threshold(PT)and pain tolerance threshold(PTT),and the pain degree(PD)was obtained.Visual Analog Scale(VAS)was used to obtain pain scores at the same time.POD was assessed 1～3days after operation using the Confusion Assessment Method(CAM),and was divided into two groups according to the assessment:the delirium group(POD group)and the non-delirium group(NPOD group).General clinical data,pain threshold test results,surgical anesthesia related data,occurrence of POD and postoperative related data were recorded.Results:A total of 11 patients(9.17%)developed POD.PTT in POD group was significantly lower than that in NPOD group(P<0.05).Multivariate Logistic regression analysis showed that the lower PTT was a risk factor for POD(P<0.05).The area under the ROC curve of POD predicted by PTT was0.697,the critical value was 136.1,the sensitivity was 81.8%,and the specificity was 56.0%(P<0.05).But PT and PD had little correlation with POD.Conclusions:Lower PTT is one of the risk factors for POD occurrence in elderly patients undergoing laparoscopic surgery,and its value lower than136.1 may have a certain predictive value for POD.PTT<136.1 can be used as an indicator to predict POD.