Sergi G, Bussolotto M, Perini P, Calliari I, Giantin V, Ceccon A, Scanferla F, Bressan M, Moschini G, Enzi G
Department of Internal Medicine, University of Padova, Italy.
Ann Nutr Metab. 1994;38(3):158-65. doi: 10.1159/000177806.
Bioelectrical impedance analysis (BIA) is a noninvasive method recently introduced for body fluid evaluation in healthy subjects. The purpose of this paper is to verify the reliability of bioelectrical measurements in extracellular water (ECW) prediction in healthy subjects and in fluid retention states. We studied 40 subjects (19 males and 21 females) aged 21-81 years; 22 were healthy subjects, 12 were affected by chronic heart failure, and 6 by chronic renal failure. In all subjects resistance (R) and reactance (Xc) at 1 and 50 kHz corrected for height were compared with ECW measured by the bromide dilution method. Our results suggested a different behavior of the current in fluid-retention states with respect to healthy subjects. ECW was best predicted by resistance at 1 kHz corrected for height, group (considered as dummy variable), weight and gender (R2 = 0.89, p < 0.001, SEE = 1.7 liters). The bioelectrical impedance analysis at 50 kHz explained the 89% of ECW variability when resistance and reactance corrected for height are considered with gender group and weight (R2 = 0.89, p < 0.001, SEE = 1.7 liters). In conclusion, the bioelectrical method at 1 kHz can be considered sufficiently accurate in ECW prediction in healthy subjects and in fluid retention states. Also, the bioelectrical impedance analysis at 50 kHz is useful for predicting ECW, but his role must be further investigated.
生物电阻抗分析（BIA）是最近引入的一种用于评估健康受试者体液的非侵入性方法。本文的目的是验证生物电测量在预测健康受试者以及体液潴留状态下细胞外液（ECW）方面的可靠性。我们研究了40名年龄在21 - 81岁之间的受试者（19名男性和21名女性）；其中22名是健康受试者，12名患有慢性心力衰竭，6名患有慢性肾衰竭。在所有受试者中，将身高校正后的1kHz和50kHz时的电阻（R）和电抗（Xc）与通过溴化物稀释法测量的ECW进行比较。我们的结果表明，与健康受试者相比，体液潴留状态下电流的行为有所不同。通过身高校正后的1kHz电阻、组别（视为虚拟变量）、体重和性别对ECW的预测效果最佳（R2 = 0.89，p < 0.001，标准误差估计值SEE = 1.7升）。当考虑身高校正后的电阻和电抗以及性别组和体重时，50kHz的生物电阻抗分析解释了89%的ECW变异性（R2 = 0.89，p < 0.001，SEE = 1.7升）。总之，1kHz的生物电方法在预测健康受试者以及体液潴留状态下的ECW方面可被认为具有足够的准确性。此外，50kHz的生物电阻抗分析对预测ECW有用，但其作用还需进一步研究。
