目的：研究不同麻醉深度指数（CSI）调控对老年创伤骨科手术患者血清S100β蛋白水平与术后认知功能障碍（POCD）的相关性。方法：选择我院2022年9月至2024年9月收治的100例老年创伤骨科手术患者为研究对象，依据随机数字表法分为高CSI组（CSI维持60~70，n=50）和低CSI组（CSI维持40~50，n=50）。比较两组麻醉时间、术后苏醒时间、定向力恢复时间、麻醉药物用量、平均动脉压（MAP）、心率（HR）、血清S100β蛋白（S100β）、简易智能量表（MMSE），通过Spearman系数分析CSI水平与S100β、POCD的相关性。结果：两组术后苏醒时间、定向力恢复时间、麻醉药使用情况比较，差异无统计学意义（P>0.05）；与低CSI组比较，高CSI组麻醉时间降低（P<0.05）。两组麻醉前、麻醉30 min后、手术结束时HR、MAP水平比较，差异无统计学意义（P>0.05）。麻醉30 min后、手术结束时S100β水平比较，高CSI组低于低CSI组（P<0.05）。与术前1 d比较，两组术后7 d MMSE评分降低且高CSI组高于低CSI组；与低CSI组比较，高CSI组CSI增高，POCD发生率降低（P<0.05）。经相关性分析，CSI水平与S100β、POCD呈显著负相关（P<0.05）。结论：保持CSI指数在60~70范围内，对于老年创伤骨科手术患者的围手术期指标具有积极影响，有助于保持血流动力学的稳定状态，并能有效降低S100β蛋白含量及术后POCD的风险。此外，CSI指数与S100β蛋白水平及POCD的发生率之间存在显著的负相关性，在临床治疗中应予以高度关注。

Objective： To study the correlation of cerebral state index （CSI） regulation on serum S100β protein level and postoperative cognitive dysfunction （POCD） in elderly patients undergoing orthopedic trauma surgery.Methods： 100 elderly patients underwent traumatic orthopedic surgery in our hospital from September 2022 to September 2024 were selected as the research objects and randomly divided into the high CSI group （CSI maintained at 60-70， n=50） and the low CSI group （CSI maintained at 40-50， n=50）. The anesthesia time， postoperative recovery time， recovery time of orientation， anesthetic dosage， mean arterial pressure （MAP）， heart rate （HR）， serum S100β protein （S100β） and mini-mental state examination （MMSE） were compared between the two groups， and the correlation between CSI level and S100β and POCD was analyzed by Spearman's correlation.Results： There was no significant difference in the postoperative recovery time， orientation recovery time， and anesthetic dosage between the two groups （P>0.05）. Compared with the low CSI group， the anesthesia time in the high CSI group was significantly lower （P<0.05）. There was no significant difference in the HR and MAP levels before anesthesia， after 30 min of anesthesia， and at the end of surgery between the two groups （P>0.05）. Comparing S100β levels after 30 min of anesthesia and at the end of surgery， the high CSI group was significantly lower than the low CSI group （P<0.05）. Compared with one day before operation， the MMSE score of the two groups decreased on the seventh day after operation， and the high CSI group was higher than the low CSI group. Compared with the low CSI group， the high CSI group significantly increased the CSI and decreased the incidence of POCD （P<0.05）. After correlation analysis， CSI level was significantly negatively correlated with S100β and POCD， both （P<0.05）.Conclusion： Keeping the CSI index in the range of 60-70 has a positive impact on the perioperative indexes of elderly trauma orthopedic surgery patients， which helps to maintain the hemodynamic steady state and effectively reduces the S100β protein level and the risk of postoperative POCD. In addition， there is a significant negative correlation between CSI index and S100β protein level and the incidence of POCD， which should be highly concerned in clinical treatment.