Effects of inhaled oxygen concentrations on cerebral oxygen saturation and postoperative short-term cognitive function in elderly patients undergoing lumbar surgery

Ye Xuefei; Jiang Xiaofeng; Wang Chenyu; Zeng Ruifeng; Liu Huacheng

doi:10.3760/j.issn.1673-4777.2023.12.018

Abstract：Objective To explore the effects of inhaled oxygen concentrations on cerebral oxygen saturation and postoperative short-term cognitive function in elderly patients undergoing lumbar surgery.Methods Totally 45 elderly patients who underwent elective lumbar surgery in the Second Affiliated Hospital of Wenzhou Medical University from October 2020 to January 2021 were selected.They were divided into groups A,B,and C by the random number table method,with 15 cases in each group.The intraoperative inhalation oxygen concentrations in groups A,B,and C were 30％,60％and 80％,respectively.The general information of patients was recorded,and the vital signs,oxygen saturation,pain visual analog scale scores,arterial blood gas analysis results,and Mini-Mental State Examination(MMSE)scores were compared at different time points in each group.Results There were no statistically significant differences in surgical time and anesthesia time among the three groups(all P＞0.05).There were no statistically significant differences in cerebral oxygen saturation among the three groups at three time points before induction(T1),30 min before surgery(T2),and 5 min after extubation(T3)(all P＞0.05).There were no statistically significant differences in the scores of the visual analog pain scale among the three groups immediately after surgery and on the first and third day after surgery(all P＞0.05).The partial pressure of arterial oxygen in group B and group C was higher than that in group A,group C was higher than that in group B at T2 and T3(all P＜0.05);however,there was no significant difference in arterial blood partial pressure of carbon dioxide and arterial blood lactate level among groups at each time point(all P＞0.05).There was no significant difference in MMSE score among three groups at each time point(all P＞0.05).The MMSE scores of the three groups decreased to varying degrees on the first and third day after surgery compared to the first day before surgery,and increased again on the third day after surgery compared to the first day after surgery;the MMSE scores on the first day after surgery showed statistically significant differences compared to the first day before surgery[(21.2±1.6)vs(23.2±1.6),(21.4±1.5)vs(23.1±1.8),(21.1±2.0)vs(23.0±1.7)](P＜0.01 or P＜0.05).The analysis of variance of grouping and time and their interaction showed no interaction effect between grouping and time(F=0.329,P=0.858).Conclusions After the lumbar surgery,elderly patients may suffer from cognitive impairment in the short-term.Different inhaled oxygen concentrations had no significant effect on cerebral oxygen saturation and postoperative short-term cognitive function.