Development of a Novel Device for Non-invasive Leg Fluid Volume Measurement

Cole, Thomas 1, 2; Popovic, Milos 1, 2; Yadollahi, Azadeh 1, 2

1. Institute of Biomaterials and Biomedical Engineering, University of Toronto; 2. Toronto Rehabilitation Institute, University Health Network

Accurate estimation of hydration status is important for the management of hemodialysis. Clinical observation is typically inaccurate and only observable after excess edema has accumulated. Bioimpedance analysis is a cost-effective and convenient method of measuring body fluid volumes. Recent studies have indicated that bioimpedance analysis of the calf can accurately predict when subjects undergoing hemodialysis have achieved “dry weight”. There is a gap in the market for a portable device that can perform continuous bioimpedance analysis to predict calf fluid volume.

Therefore the objective of my research is to develop a portable device that can continuously measure bioimpedance, and, through collaboration with Myant, a company specializing in e-textiles, produce a convenient dry electrode textile sock that will work with the device to estimate calf fluid volume. The preliminary device design has achieved results comparable to equivalent devices on the market, and, the dry electrode textile socks show promising results, in early testing, when compared with typical gel electrodes. Future work will test the integration of the device prototype with the dry electrode socks. The system will fill the need for a practical tool that is portable and easy to use to measure fluid volume in the leg. The proposed system can have a significant clinical role in monitoring edema and body composition in the leg.