Relationship Between RScO₂ Change Rate And Postoperative Delirium In Cardiac Valve Replacement With Cardiopulmonary Bypass

Objectives To study the relationship between regional cerebral oxygen saturation change rate and postoperative delirium in cardiac valve replacement with cardiopulmonary bypass.Methods A prospective clinical study was conducted to collect 54 patients undergoing cardiopulmonary bypass cardiac valve surgery from January 2021 to January 2022.Patients were divided into postoperative delirium group（P group）and non-postoperative delirium group（NP group）according to CAM evaluation results 1 to 7 days after surgery.The rScO₂,nasal temperature,anal temperature and oxygenation index were recorded at 6time points after entry（T0）,end of anesthesia induction（T1）,beginning of surgery（T2）,completion of cardiac arrest and cooling（T3）,end of cardiopulmonary bypass（T4）and end of surgery（T5）,and calculate the various points rScO₂change rate and the ratio ofrScO₂to T0;The maximum and minimum of rScO₂during surgery and cardiopulmonary bypass were recorded,the change rate of rScO₂and the ratio of rScO₂to T0 at each time point were calculated.Other indicators including age,sex,BMI,hemoglobin,preoperative MMSE score,history of hypertension,history of diabetes,education level,operation time,anesthesia time,cardiopulmonary bypass time,intraoperative fluid volume,urine volume,intraoperative dosage of anesthetics,vasoactive drugs,postoperative mechanical ventilation time and ICU stay time were recorded.SPSS 24.0 software was used to analyze the data,and P<0.05 was considered statistically significant.Results 1 Among the patients finally included in the study,31 cases were male,accounting for 57.4%;23 cases were female,accounting for 42.6%.There were 25 cases of POD,accounting for 46.30%,among which 15 cases were male accounting for 60%.10cases were female,accounting for 40%;The age of P group was higher than that of NP group,and the difference between the two groups was statistically significant（P=0.03）.The preoperative MMSE score of the P group was lower than that of the NP group,and the difference between the two groups was statistically significant（P=0.02）.There were no significant differences in ASA grade,NYHA grade,BMI,education level,gender,diabetes and hypertension between the two groups（P>0.05）.2 The intraoperative dosage of midazolam,dexmedetomidine,dopamine,norepinephrine and nitroglycerin in the P group were higher than those in the NP group,and the mechanical ventilation time and ICU stay time were longer than those in the NP group,with statistically significant differences between the two groups（P<0.05）,while there was no statistically significant difference in the dosage of propofol between the two groups.3 There were no significant differences in oxygenation index,nasal temperature and anal temperature between the two groups.4 The minimum rScO₂and minimum rScO₂/T0 in the P group were lower than those in the NP group during surgery and cardiopulmonary bypass,and the change rate of minimum rScO₂was higher than that in the NP group.The difference between the two groups was statistically significant（P<0.001）.5 The rScO₂and rScO₂/T0 of P group at T3 were lower than that of NP group,and the rScO₂change rate at T3 was higher than that of NP group,the difference between the two groups was statistically significant（P<0.05）.6 In univariate analysis,cardiopulmonary bypass time,mechanical ventilation time,intraoperative red blood cell and precipitation infusion amount,midazolam dosage,intraoperative minimum rScO₂change rate and rScO₂change rate of T3 had statistical significance（P<0.05）.7 In multivariate analysis,rScO₂change rate of T3,mechanical ventilation time and red blood cell infusion volume were statistically significant（P<0.05）.The rScO₂change rate of T3,mechanical ventilation time and red blood cell infusion volume are the risk factors of POD.8 Anal temperature,nasal temperature and Hct are the influencing factors of rScO₂.Conclusions The rScO₂changed the most at T3 time point compared with T0,and the rate of change at T3 time point was correlated with postoperative delirium.Figure 0;Table 9;Reference 141...