Abstract: Objective To investigate the effect of different time points of operation on perioperative complications and length of hospital stays in the elderly patients undergoing robot-assisted laparoscopic radical prostatectomy (RARP). Methods In this study, 358 elderly patients who underwent elective RARP surgery in Nanjing Drum Tower Hospital from April 2018 to June 2021 were divided into the morning group and the afternoon group according to whether the starting time of the operation was before 12:00. There were 141 cases in the morning group and 217 cases in the afternoon group. The differences in the preoperative general clinical data and the incidence of intraoperative and postoperative complications were compared between the two groups. Results There were no significant differences in preoperative clinical data between the two groups (P>0.05). Intraoperative blood glucose levels, incidence rate of hyperglycemia and intraoperative blood loss were significantly higher in the morning group than those in the afternoon group(P<0.05).The incidence rate of postoperative acute kidney injury (AKI) showed no significant difference between the two groups. While the level of creatinine was significantly higher and the glomerular filtration rate was significantly lower in the morning group than that in the afternoon group (P<0.05). Furthermore,there was no significant difference in the postoperative urea nitrogen level, postoperative infection rate,the incidence rate of other complications and the length of hospital stays between the two groups (P>0.05).However, the levels of white blood cell count, Neutrophil count, Monocyte count and C-reactive protein level in the morning group were higher than those in the afternoon group(P<0.05). Conclusions Under the conditions of this study, the elderly patients undergoing RARP in the afternoon were more likely to reduce the occurrence of intraoperative hyperglycemia and intraoperative blood loss, protect kidney function and alleviate immune response. However, the starting time of surgery has no significant effect on the incidence of other complications and length of hospital stay.

Key words: aged, starting time of operation, complication