Application of Remote Dielectric Sensing in Volumetric Evaluation for Maintenance Hemodialysis Patients

Background: Fluid overload increases the risk of cardiovascular events and all-cause mortality in hemodialysis patients. Remote dielectric sensing (ReDS) is a newly wearable device which can evaluate the volumetric status via the ratio of fluid and air in pulmonary tissue. In this study we explored whether ReDS can be used in evaluation of volume status in dialysis patients. Methods: We involved maintenance hemodialysis patients in the cross-sectional study and obtained both pre- and post-dialysis ReDS values. We also collected pre- and post-dialysis over hydration values by bioelectrical impedance analysis and biochemistry indicators like brain natriuretic peptide and analyzed their correlations with ReDS values to explore whether ReDS was feasible in fluid assessment for hemodialysis patients. Results: 115 maintenance hemodialysis patients were enrolled. The average pre-dialysis ReDS reading was 27.47% ± 4.88% (range from 16.00% to 39.00%), and the median post-dialysis ReDS value was 24% (range from 16% to 37%). ReDS can distinguish fluid overload patients (pre-dialysis over hydration value≥2.5L, p<0.001). ReDS value has a positive correlation with over hydration value (pre-dialysis: R=0.38, p<0.001) and a negative correlation with left ventricular ejection fraction (R=-0.333, p=0.018). ROC analysis showed that cut-off of pre-dialysis ReDS value to discriminate pre-dialysis over hydration value≥2.5L was 26.5%.Conclusion: ReDS has potential in fluid evaluation for maintenance hemodialysis patients and can serve as a useful tool to assist in clinical hydration status assessment.