目的 比较老年患者硬膜外联合全身麻醉和单纯全身麻醉对开腹结肠癌根治术调节性T淋巴细胞（Tregs）表达和术后认知功能障碍（POCD）的影响。方法 择期开腹行结肠癌根治术的100例老年患者，随机分为硬膜外联合全身麻醉组和全身麻醉组。麻醉诱导前、术后1天检测CD4，CD25和CD27，并计算其在CD4+ T淋巴细胞中的比例。术前及术后6小时、术后1天、3天、5天采用简易智能评分评估认知功能。结果 两组患者术后1天 CD4+CD25+CD127-Tregs占CD4+ T淋巴细胞的比例均较术前增加（P＜0.05），与全身麻醉组相比，硬膜外联合全身麻醉组术后1天的Tregs比例明显降低（P＜0.05）；术后各时点POCD发生率组间比较，硬膜外联合全身麻醉组低于单纯全身麻醉组（P＜0.05）；组内根据是否发生POCD分层，术后第1天未发生POCD患者中Tregs比例均低于发生POCD的患者（P＜0.05）。结论 硬膜外联合全身麻醉可降低老年患者Tregs表达水平，并可降低老年患者开腹结肠癌根治术POCD发生率。

Objective To observe the effect of epidural anesthesia combined with general anesthesia on regulatory T lymphocytes (Tregs) and postoperative cognitive dysfunction (POCD) in elderly patients underwent open colectomy. Methods Between September 2015 and October 2017, 100 elderly patients who underwent elective open colectomy were enrolled and randomly divided into two groups, epidural anesthesia combined with general anesthesia group and general anesthesia group. Venous blood was collected before the induction of anesthesia and 1 day after the operation. CD4, CD25 and CD27 were detected by flow cytometry, and the ratio of CD4 + CD25 + CD127-Treg in CD4 + T lymphocytes was calculated. Cognitive function was evaluated by Mini-Mental State Examination (MMSE) at 1d before the operation, 6h, 1d, 3d, and 5d postoperatively respectively. Results Compared with the value before the operation, the proportion of CD4 + CD25 + CD127-Tregs in both groups was significantly increased on the first day after the surgery(P <0.05), and that in epidural anesthesia combined with general anesthesia group was lower than that in general group (P <0.05). 6h, 1d, 3d, and 5d after the surgery, the incidence of POCD was lower in epidural anesthesia combined with general anesthesia group than that in general anesthesia(P <0.05); On the first day after the operation, the proportion of Tregs in CD4+ T lymphocytes indicated significantly lower expression in patients without POCD than that in patients with POCD (P <0.05). Conclusion The expression of Tregs in patients underwent general anesthesia combined with epidural anesthesia is lower than that of general anesthesia alone, and it can decrease the incidence of POCD in elderly patients with open colectomy.

内蒙古自然科学基金面上项目(项目名称：Tregs在不同麻醉方法中对老年患者术后脑认知功能的影响；内蒙古医科大学科技百万工程项目（项目名称：剖宫产患者采用对乙酰氨基酚联合PCEA多模式术后镇痛：一项随机双盲安慰剂对照临床试验；项目编号：YKD2020KJBW(LH)）项目编号：2017MS08107)；