Prediction of hemodialysis vascular access failure using segmental bioimpedance analysis parameters.

Abstract

Segmental bioimpedance analysis (BIA) can identify fluid volume changes in the arms of patients on hemodialysis (HD) after vascular access surgery. We investigated whether the difference in fluid volumes between the arms of the patients using segmental BIA is associated with vascular access outcome. Body composition measurements were taken for 127 patients on HD with segmental, multi-frequency BIA equipment (InBody 1.0, Biospace Co. Ltd, Seoul, Korea). The difference in fluid volume between the arms of the patients was calculated from the fluid volume of the arm with the vascular access minus that of the other. The primary outcome was the loss of vascular access patency within 3months of BIA measurement. The median absolute and relative inter-arm fluid volume differences were 150ml [interquartile range (IQR) 90-250ml] and 9.6% (IQR 4.9-14.4%), respectively. Within 3months of BIA measurement, 38 patients (30.0%) experienced vascular access failure. When the patients were divided into three groups based on the tertiles of relative inter-arm fluid volume differences (lowest tertile:<6.8%; middle tertile: 6.8-12.7%; highest tertile:>12.7%), greater difference in relative inter-arm fluid volume differences was associated with higher vascular access failure rates (14 vs. 28 vs. 48%, p value for trend across tertiles=0.003). We conclude that segmental BIA may be used as a tool that can predict vascular access failure in patients on HD by calculating the relative difference in fluid volume between the arms of the patients with and without vascular access.