US Army Research Institute of Environmental Medicine, Natick, MA, USA.
Am J Clin Nutr. 2013 Mar;97(3):455-62. doi: 10.3945/ajcn.112.044172. Epub 2013 Jan 23.
Dehydration (body water deficit) is a physiologic state that can have profound implications for human health and performance. Unfortunately, dehydration can be difficult to assess, and there is no single, universal gold standard for decision making. In this article, we review the physiologic basis for understanding quantitative dehydration assessment. We highlight how phenomenologic interpretations of dehydration depend critically on the type (dehydration compared with volume depletion) and magnitude (moderate compared with severe) of dehydration, which in turn influence the osmotic (plasma osmolality) and blood volume-dependent compensatory thresholds for antidiuretic and thirst responses. In particular, we review new findings regarding the biological variation in osmotic responses to dehydration and discuss how this variation can help provide a quantitative and clinically relevant link between the physiology and phenomenology of dehydration. Practical measures with empirical thresholds are provided as a starting point for improving the practice of dehydration assessment.
脱水（体液不足）是一种生理状态，可能对人类健康和表现产生深远影响。不幸的是，脱水很难评估，而且没有单一的、普遍的黄金标准来做出决策。在本文中，我们回顾了理解定量脱水评估的生理基础。我们强调了对脱水的现象学解释如何严重依赖脱水的类型（与容量不足相比）和程度（与中度相比，严重程度），这反过来又影响抗利尿和口渴反应的渗透（血浆渗透压）和血容量依赖性补偿阈值。特别是，我们回顾了关于脱水时渗透压反应的生物学变异性的新发现，并讨论了这种变异性如何有助于在脱水的生理学和现象学之间建立定量的、临床相关的联系。提供了具有经验阈值的实用措施作为改善脱水评估实践的起点。
