Department of Anesthesiology & Perioperative Care, University of California, Irvine, USA.
Anesth Analg. 2012 Jan;114(1):130-43. doi: 10.1213/ANE.0b013e318230e9e0. Epub 2011 Sep 29.
Closed-loop (automated) controllers are encountered in all aspects of modern life in applications ranging from air-conditioning to spaceflight. Although these systems are virtually ubiquitous, they are infrequently used in anesthesiology because of the complexity of physiologic systems and the difficulty in obtaining reliable and valid feedback data from the patient. Despite these challenges, closed-loop systems are being increasingly studied and improved for medical use. Two recent developments have made fluid administration a candidate for closed-loop control. First, the further description and development of dynamic predictors of fluid responsiveness provides a strong parameter for use as a control variable to guide fluid administration. Second, rapid advances in noninvasive monitoring of cardiac output and other hemodynamic variables make goal-directed therapy applicable for a wide range of patients in a variety of clinical care settings. In this article, we review the history of closed-loop controllers in clinical care, discuss the current understanding and limitations of the dynamic predictors of fluid responsiveness, and examine how these variables might be incorporated into a closed-loop fluid administration system.
闭环（自动）控制器在现代生活的各个方面都有应用，从空调到太空飞行。尽管这些系统无处不在，但由于生理系统的复杂性以及从患者那里获得可靠和有效反馈数据的困难，它们在麻醉学中很少使用。尽管存在这些挑战，但闭环系统仍在不断被研究和改进，以用于医疗用途。最近的两项发展使输液成为闭环控制的候选对象。首先，对液体反应性的动态预测器的进一步描述和发展为使用控制变量来指导输液提供了一个强有力的参数。其次，非侵入性心输出量和其他血流动力学变量监测的快速发展使得目标导向治疗适用于各种临床护理环境中的广泛患者。本文回顾了闭环控制器在临床护理中的历史，讨论了目前对液体反应性的动态预测器的理解和局限性，并探讨了这些变量如何被纳入闭环输液系统。
