AGING AND COGNITION AFTER CARDIAC SURGERY

据估计，将有30万名患者接受冠状动脉搭桥术 (CABG)手术于1994年。其中越来越多的患者是 老年人，我们刚刚发现这个患者群体是 尤其易患心脏术后早期认知功能障碍 做手术。术后即刻的神经心理功能障碍 月经是一个令人不安的临床问题，通常(在多达 83%的患者)使手术成功复杂化。我们将测试 低温保护大脑免受损伤的假说(如图所示 在心脏手术期间)。这是第一次 亚低温对大鼠脑损伤保护作用的前瞻性研究 冠心病患者术后神经心理功能障碍的发生率 动脉搭桥术(CABG)患者。400名冠脉搭桥术患者将接受 入伍超过四年。这一假设将通过随机化进行检验。 年龄分层的患者达到常温(36%摄氏度)和中等(28摄氏度) 冠状动脉旁路移植术中的低温灌流。体温过低会产生 大脑代谢抑制和两者之间的关系 体温灌流会改变脑氧代谢 用Xe133清除率和颈动脉球静脉测定 计算脑氧代谢率的氧梯度 (CMRO2)。调查的主要目的是确定 体温过低可保护患者免受认知功能障碍的影响。这些变化 在CMRO2中以及低温保护时间将相关 在一系列神经学和药物治疗中的变化 心理测试。认知功能的改变将与 CPB期间CMRO2和时间积分(低温)的降低。一个 调查的次要目标是确定认知能力 功能障碍会导致生活质量的下降，并增加 医院费用。这将通过使用开发的一组测试来完成 由我们的调查人员衡量生活质量，并通过详细的成本 这里还开发了分析程序，以检查医疗保健成本之后 心脏手术。在这次调查中产生的新知识将会 立即适用于临床心脏手术。结果可能是 从以下方面论证维持认知功能的重要性 生活质量和经济措施。此外，这些信息将 扩大我们对体温过低的保护作用的理解 缺血性侮辱。

An estimated 300,00 patients will undergo coronary artery bypass graft (CABG) surgery in 1994. An increasing number of these patients are elderly, and we have just found that this patient population is particularly susceptible to early cognitive dysfunction after cardiac surgery. Neuropsychologic dysfunction in the immediate postoperative period is a disturbing clinical problem which often (in up to as many as 83% of patients) complicates successful surgery. We will test the hypothesis that hypothermia protects the brain from injury (as manifested in altered cognitive function) during cardiac surgery. This is the first prospective study of the protective effect of hypothermia on the postoperative incidence of neuropsychologic dysfunction in coronary artery bypass surgical (CABG) patients. 400 CABG patients will be enrolled over four years. The hypothesis will be tested by randomization of age stratified patients to normothermic (36%C) and moderate (28$C) hypothermic perfusion during CABG surgery. Hypothermia produces cerebral metabolic suppression and the degree to which the two temperature perfusions alter cerebral oxygen metabolism will be determined using Xe133 clearance and arterial - jugular bulb venous oxygen gradients to calculate the cerebral metabolic rate of oxygen (CMRO2). The primary aim of the investigation is to determine whether hypothermia protects the patient from cognitive dysfunction. The changes in CMRO2 as well as the time of hypothermic protection will be correlated with the changes in a serially administered battery of neurologic and psychometric tests. Change in cognitive function will be correlated with the reduction in CMRO2 and time integral (hypothermia) during CPB. A secondary aim of the investigation is to determine whether cognitive dysfunction leads to impairment in the quality of life and adds to hospital costs. This will be done by using a battery of tests developed by our investigators to measure quality of life and by a detailed cost analysis program also developed here to examine health care costs after cardiac surgery. New knowledge generated in this investigation will have immediate applicability to clinical cardiac surgery. The results may demonstrate the importance of maintaining cognitive function in terms of quality of life and economic measures. Furthermore, the information will expand our understanding of the protective effects of hypothermia against ischemic insult.