RESUMEN
Objective:To evaluate the relationship between postoperative delirium and preoperative modified frailty index (mFI) score in elderly patients undergoing colorectal cancer surgery.Methods:The medical records of elderly patients of either sex, aged 65-90 yr, with primary tumor, without radiotherapy and chemotherapy before operation, with the expected operating time ≥ 2 h, undergoing colorectal cancer surgery under general anesthesia, were collected.The patients′ preoperative frailty was assessed using mFI scale.Primary outcome was the incidence of delirium within 7 days after operation, and delirium was assessed using Confusion Assessment Method.The preoperative baseline characteristics, BI score, mFI score and Mini-Mental State Examination were recorded; anesthesia-related information, surgery-related information, intraoperative adverse events, total volume of intraoperative fluid infused, blood loss, and urine output were recorded.The patients were divided into delirium group (D group) and non-delirium group (N group) according to whether delirium occurred or not, and logistic regression analysis was used to screen the risk factors for postoperative delirium in elderly patients with colorectal cancer.Results:A total of 370 patients were enrolled in this study, and the incidence of delirium was 10.8%.There were significant differences in age, ASA grading ratio, mFI score, anesthetic time and total volume of intraoperative fluid infused between group N and group D ( P<0.05). The results of multivariate logistic regression analysis showed that increased age and mFI were independent risk factors for the occurrence of postoperative delirium ( P<0.05). Conclusions:Increased mFI score and age are independent risk factors for postoperative delirium in elderly patients undergoing colorectal cancer.