Department of Rehabilitation, Nagoya University Hospital, Nagoya, Japan; Multidisciplinary Pain Center, Aichi Medical University, Nagakute, Japan; Department of Rehabilitation, Aichi Medical University, Nagakute, Japan.
Department of Cardiac Surgery, Nagoya University Graduate School of Medicine, Nagoya, Japan.
Ann Thorac Surg. 2018 Aug;106(2):505-512. doi: 10.1016/j.athoracsur.2018.03.010. Epub 2018 May 10.
Postoperative cognitive dysfunction (POCD) is a neurologic dysfunction that occurs after surgery. POCD persists for a long period, ranging from weeks to months, and affects a patient's quality of life. A 6-minute walk distance (6MWD) has been used to predict postoperative complications after several operations. The present study investigated whether there was an independent association of a low preoperative 6MWD with POCD in patients who underwent cardiac operations.
The study included 181 patients who underwent a cardiac operation. The 6MWD was performed prospectively on admission for the operation. POCD was defined as a decrease of 2 points or more in a patient's Mini-Mental State Examination score. POCD developed in 51 (28%) of these patients. Patients were categorized into a POCD or a non-POCD group, and the perioperative variables were compared between the groups. Multivariable logistic regression analysis was performed to identify risk factors for the development of POCD.
The patients were a mean age of 71.4 years. The POCD group showed a significantly lower 6MWD (median, 400 m) than the non-POCD group (median, 450 m). The 6MWD, intensive care unit length of stay, age, and Mini-Mental State Examination score were identified as independent risk factors for POCD by multivariable analysis. The odds ratio for each increase of 50 m in the 6MWD was 0.807 for POCD.
The 6MWD is useful in identifying patients with a higher chance of developing POCD after a cardiac operation.
术后认知功能障碍（POCD）是手术后发生的神经功能障碍。POCD 持续时间长，从数周到数月不等，影响患者的生活质量。6 分钟步行距离（6MWD）已被用于预测多种手术后的术后并发症。本研究旨在探讨术前 6MWD 较低与接受心脏手术的患者发生 POCD 是否存在独立关联。
该研究纳入了 181 例接受心脏手术的患者。在手术前，前瞻性地进行了 6MWD 测试。POCD 定义为患者的简易精神状态检查评分下降 2 分或以上。这些患者中有 51 例（28%）发生了 POCD。将患者分为 POCD 组或非 POCD 组，比较两组之间的围手术期变量。采用多变量逻辑回归分析确定 POCD 发展的危险因素。
患者平均年龄为 71.4 岁。POCD 组的 6MWD（中位数，400m）明显低于非 POCD 组（中位数，450m）。多变量分析显示，6MWD、重症监护病房住院时间、年龄和简易精神状态检查评分是 POCD 的独立危险因素。6MWD 每增加 50m，POCD 的比值比为 0.807。
6MWD 可用于识别心脏手术后发生 POCD 几率较高的患者。
