Effects of Single Low Dose of Dexamethasone before Noncardiac and Nonneurologic Surgery and General Anesthesia on Postoperative Cognitive Dysfunction—A Phase III Double Blind, Randomized Clinical Trial

Postoperative cognitive dysfunction (POCD) is a multifactorial adverse event most frequently in elderly patients. This study evaluated the effect of dexamethasone on POCD incidence after noncardiac and nonneurologic surgery. METHODS: One hundred and forty patients (ASA I-II; age 60–87 years) took part in a prospective phase III, double blind, randomized study involving the administration or not of 8 mg of IV dexamethasone before general anesthesia under bispectral index (BIS) between 35–45 or 46–55. Neuropsychological tests were applied preoperatively and on the 3rd, 7th, 21st, 90th and 180th days after surgery and compared with normative data. S100β was evaluated before and 12 hours after induction of anesthesia. The generalized estimating equations (GEE) method was applied, followed by the posthoc Bonferroni test considering PTrial Registration:www.clinicaltrials.govNCT01332812

术后认知功能障碍（Postoperative Cognitive Dysfunction, POCD）是一种多因素不良事件，在老年患者中最为高发。本研究评估了地塞米松对非心脏、非神经外科手术后POCD发生率的影响。方法：本研究共纳入140例患者（美国麻醉医师协会（ASA）分级I~II级；年龄60~87岁），采用前瞻性Ⅲ期双盲随机研究设计，于全身麻醉诱导前给予或不予8 mg静脉注射地塞米松，麻醉期间维持脑电双频指数（bispectral index, BIS）于35~45或46~55区间。分别于术前、术后第3、7、21、90及180天实施神经心理学测试，并与常模数据进行对比分析。分别于麻醉诱导前及诱导后12小时检测S100β蛋白水平。本研究采用广义估计方程（generalized estimating equations, GEE）进行统计分析，随后采用事后Bonferroni检验；临床试验注册信息：www.clinicaltrials.gov，注册号NCT01332812。