Correlation of blood glucose variability based on CGMS monitoring during cardiopulmonary bypass and postoperative delirium in patients with rheumatic heart disease valve replacement

To investigate the relationship between blood glucose variability based on continuous glucose monitoring system (CGMS) monitoring and postoperative delirium (POD) in patients with rheumatic heart disease undergoing valve replacement during cardiopulmonary bypass. From July 2021 to July 2022, we conducted real-time dynamic blood glucose monitoring after admission to the operating room in 122 patients undergoing valve replacement for rheumatic heart disease. CGMS were used to record indicators related to blood glucose variation, including CV, GluAve, GluSD and MAGE, and MMSE was also used for evaluation one day before surgery. To rule out preoperative cognitive impairment. At postoperative days 1, 2, and 3, the CAM-ICU scale was used to assess patients' unconsciousness. Finally, binary logistic regression analysis was used to study the relationship between intraoperative blood glucose changes and POD. The age of patients with POD was significantly older than that of patients without POD, and the occurrence of POD was related to the duration of extracorporeal circulation and the value of the blood glucose variation index (CV, GluAve, GluSD, MAGE). By binary logistic regression analysis, we found that age, CPB cycle time and blood glucose variability were independent risk factors for postoperative delirium (POD) (P <0.05). In addition, we also found that the area under ROC curve of CV, GluAve, GluSD and MAGE were 0.684, 0.830, 0.820 and 0.802, respectively, which indicated that these indexes could predict the occurrence of postoperative delirium (POD). GluAve had the strongest prediction effect on POD (sensitivity 85.7%, specificity 81.5%). Blood glucose variability based on CGMS monitoring during cardiopulmonary bypass in patients with rheumatic heart disease valve replacement is associated with the occurrence of postoperative delirium. Longer duration of CPB and increased intraoperative blood glucose variability are independent risk factors for POD in patients with rheumatic heart disease valve replacement. Continuous monitoring of intraoperative blood glucose by CGMS can provide real-time guidance for early intervention of blood glucose fluctuations to reduce the incidence of postoperative POD.