Swarthmore College, Swarthmore, PA 19081, United States of America.
Physiol Meas. 2018 Dec 24;39(12):125009. doi: 10.1088/1361-6579/aaf277.
To evaluate the relationship between calf bioimpedance measurements and fluid removal in a controlled environment (hemodialysis) as a first step toward using these measurements for remote congestive heart failure (CHF) monitoring.
Calf bioimpedance measurements were recorded in 17 patients undergoing hemodialysis (9/17 (53%) CHF, 5/17 (30%) female). Measurements were performed before and after hemodialysis. Additional parameters related to hemodialysis and patient fluid status such as estimated dry weight were also recorded.
Calf bioimpedance changes depended on calf fluid status as assessed by calf normalized resistivity (CNR). Patients with lower calf fluid overload (as assessed by CNR greater than [Formula: see text] [Formula: see text]m[Formula: see text] kg[Formula: see text]) had larger decreases in calf fluid than patients with higher calf fluid overload. High CNR patients had fluid changes within the calf that depended on the ultrafiltration rate, with patients with lower ultrafiltration rates experiencing fluid shifts from extracellular to intracellular fluid. Additionally, there were correlations between changes in calf extra-, intra- and total- water and the ultrafiltration volume removed for high CNR patients ([Formula: see text], respectively, all p-values [Formula: see text] 0.05).
These results suggest that while the relationship between calf fluid status and total fluid status is complex, changes in calf volumes comparable to those expected in an ambulatory setting are measurable and relate to changes in total volume. This suggests that calf bioimpedance measurements for CHF remote monitoring warrant future investigation, as remote fluid status management could reduce fluid overload related hospitalizations in CHF patients.
评估在受控环境（血液透析）中，小腿生物阻抗测量与液体清除之间的关系，作为将这些测量值用于远程充血性心力衰竭（CHF）监测的第一步。
对 17 名接受血液透析的患者（9/17（53%）为 CHF，5/17（30%）为女性）进行了小腿生物阻抗测量。在血液透析前后进行了测量。还记录了与血液透析和患者液体状态相关的其他参数，如估计的干体重。
小腿生物阻抗的变化取决于小腿归一化电阻率（CNR）评估的小腿液体状态。与小腿液体过载（CNR 大于[公式：见文本] [公式：见文本]m[公式：见文本]kg[公式：见文本]）评估较高的患者相比，小腿液体过载较低的患者的小腿液体减少量更大。高 CNR 患者的小腿内液体变化取决于超滤率，超滤率较低的患者经历了从细胞外液到细胞内液的液体转移。此外，高 CNR 患者的小腿细胞外、细胞内和总水的变化与超滤体积去除之间存在相关性（[公式：见文本]，所有 p 值均小于 0.05）。
这些结果表明，尽管小腿液体状态与总液体状态之间的关系很复杂，但在可测量的范围内，与在非卧床环境中预期的变化相当的小腿体积变化与总体积的变化相关。这表明，CHF 远程监测的小腿生物阻抗测量值得进一步研究，因为远程液体状态管理可以减少 CHF 患者与液体过载相关的住院治疗。
