A New Device to Monitor Blood Volume in Hemodialysis Patients

We developed a new optical device (Nikkiso) to assess changes through blood volume monitoring (BVM) during hemodialysis and were able to determine the ideal levels in which changes in blood volume percentage (BV%) occur among hemodialysis patients in one hemodialysis center. We evaluated both the reliability of BVM and these ideal levels in a multicenter group. The purpose of this manuscript is to develop a navigating system to set dry weight in a variety of situations as the final goal. First, based on the obtained BVM (BV%(BVM) ) measurements, the relationships between BV% and hematocrit (BV%(HT) ) and between BV% and CRIT-LINE (BV%(CLM) ; Hema Metrics, Kaysville, UT, USA) were then evaluated. In 30 hemodialysis patients, there was a close correlation between both BV%(BVM) vs. BV%(HT) and BV%(BVM) vs. BV%(CLM) (n=30, r=0.967, P<0.001, and n=36, r=0.7867, P<0.001, respectively). Second, BV% data were obtained from 464 treatment cases performed on 26 subjects in one satellite hemodialysis center on patients whose body weight was deemed clinically suitable. The formulas for the levels of BV% (standardized by the percent change in body weight at the end of hemodialysis treatment: BW%end) were determined. Finally, we revalidated the reliability of the above levels. A total of 1126 measurements were performed on 201 patients whose body weights were deemed suitable in seven hemodialysis centers. New ideal levels were then recalculated. We therefore conclude that BVM is a sufficiently accurate method of monitoring BV% in hemodialysis treatment. Most well-controlled hemodialysis patients display the same pattern of BV%/BW%end. Monitoring BV% during hemodialysis is beneficial for determining dry weight (DW).