Abstract: Objective: To investigate the relationship between post-operative cognitive dysfunction (POCD) and regional cerebral oxygen saturation (rSO₂) and β-Amyloid protein (Aβ) in patients undergoing laparoscopic pancreaticoduodenectomy. Methods: Fifty patients undergoing elective laparoscopic pancreaticoduodenectomy received five groups of neuropsychological tests 1 d pre-operatively and 7 d post-operatively, with continuous monitoring of rSO₂ intra-operatively. Before anesthesia induction (t ₀), at the beginning of laparoscopy (t ₁), and at the time of pneumoperitoneum 120 min (t ₂), pneumoperitoneum 240 min (t ₃), pneumoperitoneum 480 min (t ₄), the end of pneumoperitoneum (t ₅), and 24 h after surgery, jugular venous blood was drawn respectively for the measurement of Aβ by enzyme-linked immunosorbent assay (ELISA). Results: Twenty-one cases of the fifty patients suffered from POCD after operation. We found that the maximum percentage drop in rSO₂ (rSO_{2, %max}) was significantly higher in the POCD group than in the non-POCD group. The rSO_{2, %max} value of over 10.2% might be a potential predictor of neurocognitive injury for those patients. In the POCD group, the plasma Aβ levels after 24 h were significantly higher than those of pre-operative values (P<0.01). After 24 h, levels of plasma Aβ in the POCD group were significantly higher than those in the non-POCD group (P<0.01). Conclusions: The development of POCD in patients undergoing laparoscopic pancreaticoduodenectomy is associated with alterations of rSO₂ and Aβ. Monitoring of rSO₂ might be useful in the prediction of POCD, and Aβ might be used as a sensitive biochemical marker to predict the occurrence of POCD.

术后认知功能障碍与脑氧饱和度及血浆β-淀粉样蛋白的关系

研究目的：探讨腹腔镜胰体尾切除术患者术后认知功能障碍（POCD）的发生与脑氧饱和度（rSO₂）及血浆β-淀粉样蛋白（Aβ）水平的相关性。
创新要点：POCD的发生机制与rSO₂及Aβ有一定的相关性；rSO₂较基础值下降的最大百分数（rSO_{2, %max}）>10.2%有可能发生POCD，因此，rSO₂监测可能是预测POCD发生的有效工具；Aβ可能是发生POCD敏感的生化预警指标。
研究方法：择期行腹腔镜胰十二指肠切除术患者50例，于术前1天和术后7天分别行简明精神状态量表（MMSE）、数字广度、数字符号、循迹连线、词汇流畅性（VFT）和单词辨认神经心理测验。分别于麻醉诱导前（t₀）、气腹开始前（t₁）、气腹120min（t₂）、气腹240min（t₃）、气腹480min（t₄）、气腹结束（t₅）及术毕24h，抽取颈内静脉血3ml，采用酶联免疫法（ELISA）方法测定Aβ含量。术中利用近红外光谱技术（NIRS）连续监测rSO₂，并计算术中rSO₂平均值、术中rSO₂最小值（rSO_{2, min}）和rSO_{2, %max}。
重要结论：POCD的发生与rSO₂及Aβ有关；危险因素可能有老年、低教育水平、较高基础体温、rSO₂下降、CO₂蓄积、血浆Aβ升高等；rSO₂监测有可能是POCD的有效预测工具之一；Aβ有可能是发生POCD敏感的生化预警标志物之一。
术后认知功能障碍；局部脑氧饱和度；β-淀粉样蛋白

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