Intraoperative Spindle Waves And Emergence Delirium In Elderly Patients Undergoing Joint Replacement Surgery

Objective To investigate the relationship between emergence delirium(ED)and the intraoperative spindle waves in elderly patients who underwent joint replacement surgery,and to analyze the independent risk factors of ED.Methods This single-center,prospective,observational cohort study involving 69 elderly patients who underwent joint replacement surgery in The Affiliated Hospital of Qingdao University between November 2020 and February 2021.Preoperative,intraoperative and postoperative informations of all patients were recorded.Patients were divided into spindle-loss group and the spindle group according to EEG analysis during operation,χ2test was used to analyze the relationship between ED and spindle.ED was assessed by the Confusion Assessment Method(CAM)every 10 minutes from the time the patients awoke to the time they came out of the post-anesthesia care unit(PACU).ED was the primary outcome.Secondary outcome included PACU duration and postoperative delirium(POD).The patients were then divided into the ED group and the non-ED group according to the occurrence of ED after surgery.Univariate analysis was conducted on the relevant observation indicators of the two groups.Factors with P < 0.05 in univariate analysis and risk factors reported in previous studies were enrolled into multivariate logistic regression to analyze the independent risk factors of ED.Results There were 17 patients spindle-loss,and ED occurred in 22 of 69(31.9%)patients,and the absence of intraoperative spindle occurred in 11(50%)of ED patients.Univariate analysis showed that there were no significant differences in preoperative and intraoperative information,PACU duration and POD between the spindle-loss group and the spindle group(P>0.05).The incidence of ED in the spindle-loss group was higher than the spindle group(64.7% vs 21.2%),the difference between the two groups was statistically significant(χ2=11.20,P<0.05).Univariate analysis showed that there were significant differences in age,gender,stroke history and spindle wave between the ED group and the non-ED group(t=-3.804,χ2=4.071～11.189,P<0.05).The results of the multivariate logistic regression analysis showed that: age(OR=1.197,95%CI=1.066～1.344)and the absence of intraoperative spindle wave(OR=6.062,95%CI=1.384 ～ 26.543)were independent risk factors for ED in elderly patients after joint replacement surgery.Conclusions The absence of intraoperative spindle waves was significantly associated with ED.Lack of the intraoperative spindle waves and age are independent risk factors for ED in elderly patients with joint replacement.