Abstract: FR-PO818

Adjustment of Target Weight Based on Absolute Blood Volume Reduces the Frequency of Intradialytic Morbid Events

Session Information

Category: Dialysis

  • 601 Standard Hemodialysis for ESRD


  • SCHNEDITZ, Daniel, Medical University Graz, Graz, Austria
  • Kron, Susanne, Charite Universitatsmedizin Berlin, Berlin, Germany
  • Leimbach, Til, KfH Kidney Center Berlin-Köpenick, Berlin, Germany
  • Budde, Klemens, Charite Universitatsmedizin Berlin, Berlin, Germany
  • Kron, Joachim, KfH Kidney Center Berlin-Köpenick, Berlin, Germany

Adequate ultrafiltration (UF) avoiding intradialytic morbid events (IME) remains a core problem in current hemodialysis (HD) therapy. The aim of this study was to investigate the suitability of absolute blood volume (Vs, in mL/kg) to prescribe UF volume and to reduce the frequency of IME.


Following a 4 week baseline phase to quantify the frequency of IME, volume status was determined in a specified HD study during which relative blood volume (RBV, %) was measured by the blood volume monitor (BVM), Vs was measured using on-line dialysate dilution, and volume overload (Vo, L) was measured using bioimpedance spectroscopy. Symptomatic IME was defined as a drop in systolic blood pressure (PSYS) by more than 20 mmHg, or a PSYS below 90 mmHg, or the occurence of symptoms such as dizziness, light-headedness, sweating, or cramps. Suitability of different variables to discriminate for IME was examined by analysis of receiver-operator-characteristics (ROC-analysis) and calculation of the area under the ROC-curve (AUROC). Target weight was then increased or decreased based on measured Vs, Vo, and occurence of IME, and the frequency of IME was recorded during 4 weeks of follow-up.


45 patients participated in this study. 22 (49%) patients experienced 66 IME in 12% of HD treatments during baseline. In 15 (33%) patients who experienced IME during the volume assessment study 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) was lower than in stable patients, while RBV (87.9±4.4 vs. 90.2±4.2%, p=n.s.) was comparable. AUROC was 0.92, 0.80, and 0.61 for Vs, Vo, and RBV, respectively. The sensitivity, specificity, and accuracy of the Vs≤65 mL/kg threshold to predict IME was 87%, 100%, and 91%, respectively. Target weight was increased (+1.5 kg) or decreased (-5kg) in 32 patients. The frequency of IME fell to 0.9% of all HD sessions in the following 4 weeks (p<0.001).


Absolute blood volume (Vs, mL/kg) is more accurate in assessing the risk for IME-prone patients than relative blood volume (RBV, %). Adjustment of target weight based on information of Vs, Vo, and IME appears as a feasible approach to reduce the frequency of IME.