Measurement accuracy of total cell volume by automated dialyzer reprocessing: A prospective cohort study

INTRODUCTION: Dialyzer reprocessing machines have replaced human labor in preparing re-usable dialyzers. It also made the process of total cell volume (TCV) measurement become faster. Nevertheless, there has been a lack of data on efficacy of weight evaluation on TCV by machine compared to volume evaluation by the conventional method. The aim of this study was to evaluate the efficacy of TCV measurement performed by Kidney-Kleen(®) reprocessing machine, produced by MEDITOP Company in Thailand, compared to that of the conventional method. METHODS: This prospective cohort study was performed during September 2014 to December 2015.The low-flux (N = 101) and high-flux dialyzers (N = 100) were included for TCV evaluation. Reused times were up to 5 in the low-flux and 20 in the high-flux dialyzers. The Bland Altman analysis was used to evaluate value measured by different methods. RESULTS: The values measured by weight evaluation (by machine) were higher than those obtained by volumetric evaluation of the conventional method in the low-flux (0.81 ± 0.20%) and high-flux (1.32 ± 0.39%) dialyzers. The correlation of TCV values of the two methods were r = 0.98, p < 0.001 and r = 0.71, p < 0.001 for the low- and high-flux dialyzers. Moreover, there was robust association and agreement between the two methods, confirmed by the Bland-Altman Analysis, which suggested that the values acquired by machine were within the limits of agreement, indicating acceptable accuracy of equipment. CONCLUSION: The approach of measurement differed from that of the conventional method (weight evaluation was used instead of volumetric evaluation), the reprocessing machine could offer accurate results.