Adjustment of target weight based on absolute blood volume reduces the frequency of intradialytic morbid events.

Abstract

Adequate volume management removing excess volume and at the same time avoiding intradialytic morbid events (IME) remains a core problem in current hemodialysis (HD) therapy. Recently, we developed a feasible method to determine absolute blood volume (Vs, in mL/kg) in patients on HD. The aim of this study was to investigate the suitability of Vs measurements for volume management. Following a 4 week baseline phase to quantify the frequency of IME, volume status was determined in a single specified HD session during which Vs was measured using dialysate dilution, volume overload (Vo, L) was measured using bioimpedance spectroscopy, and the occurrence of IME was recorded. Target weight was then adjusted and the frequency of IME was recorded during 4 weeks of follow-up. Forty-five patients participated in this study. Twenty-two (49%) patients experienced 66 IME in 12% of HD treatments during baseline. In 15 (33%) patients who experienced IME during volume assessment both Vs (60.7 ± 4.0 vs. 73.7 ± 11.3 mL/kg, P < 0.001) and Vo (1.1 ± 0.9 vs. 2.5 ± 1.8 L, P < 0.01) were significantly lower than in stable patients, respectively. The sensitivity, specificity, and accuracy of the ≤65 mL/kg Vs threshold to predict IME was 87%, 100%, and 91%, respectively. Target weight was increased (+1.5 kg) or decreased (-5 kg) in 32 patients. The frequency of IME fell to 0.9% of all HD sessions in the following 4 weeks (P < 0.001). Adjustment of target weight based on information of Vs, Vo, and IME appears as a feasible approach to reduce the frequency of IME.