Earthman Carrie, Traughber Diana, Dobratz Jennifer, Howell Wanda
University of Minnesota, 225 Food Science and Nutrition, 1334 Eckles Ave., St. Paul, MN 55108, USA.
Nutr Clin Pract. 2007 Aug;22(4):389-405. doi: 10.1177/0115426507022004389.
Body composition assessment has been used to evaluate clinical interventions in research trials, and has the potential to improve patient care in the clinical setting. Body cell mass (BCM) is an important indicator of nutrition status; however, its measurement in the clinic has been limited. BCM can be estimated by the measurement of intracellular water (ICW). The assessment of extracellular water (ECW) is also important because many clinical populations undergo alterations in fluid distribution, particularly individuals with wasting, those receiving dialysis, and obese individuals. Bioimpedance spectroscopy (BIS) is a unique bioimpedance approach that differs in underlying basis from the more readily recognized single-frequency bioelectrical impedance analysis (SF-BIA) in that it does not require the use of statistically derived, population-specific prediction equations. It has the potential advantage of not only measuring total body water (TBW), as does SF-BIA, but also offering the unique capacity to differentiate between ECW and ICW and, thus, to provide an estimate of BCM. This literature review was conducted to compare available BIS devices to multiple dilution for measuring fluid compartments or BCM in a number of populations. Variable results regarding the ability of BIS to measure absolute volumes, as well as the observation of wide limits of variation, make BIS problematic for individual assessment in the clinic, particularly in populations with abnormal fluid distribution or body geometry. BIS has been found to be more accurate for measuring changes in fluid volumes or BCM, particularly in post-surgical and human immunodeficiency virus (HIV)-infected individuals. It is certainly possible that population-specific adjustments may improve the accuracy of BIS for assessing individuals in the clinical setting; however, additional research and development is needed before the method can be accepted for routine clinical use.
身体成分评估已被用于研究试验中评估临床干预措施，并且有可能改善临床环境中的患者护理。身体细胞质量（BCM）是营养状况的重要指标；然而，其在临床中的测量一直有限。BCM可通过测量细胞内水（ICW）来估算。细胞外水（ECW）的评估也很重要，因为许多临床人群会出现液体分布的改变，特别是消瘦个体、接受透析的个体和肥胖个体。生物电阻抗光谱法（BIS）是一种独特的生物阻抗方法，其基础与更常见的单频生物电阻抗分析（SF - BIA）不同，因为它不需要使用基于统计得出的、特定人群的预测方程。它不仅具有与SF - BIA一样测量总体水（TBW）的潜在优势，还具有独特的能力来区分ECW和ICW，从而提供BCM的估计值。本综述旨在比较现有的BIS设备与多种稀释法在多个群体中测量液体成分或BCM的情况。关于BIS测量绝对体积能力的结果不一，以及观察到的广泛变异范围，使得BIS在临床个体评估中存在问题，特别是在液体分布或身体几何形状异常的人群中。已发现BIS在测量液体体积或BCM的变化方面更准确，特别是在术后和感染人类免疫缺陷病毒（HIV）的个体中。特定人群的调整有可能提高BIS在临床环境中评估个体的准确性；然而，在该方法被接受用于常规临床使用之前，还需要进一步的研究和开发。
