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An improved method to estimate absolute blood volume based on dialysate dilution
Susanne Kron1, Daniel Schneditz2, David F Keane3
1Department of Nephrology and Internal Intensive Care Medicine, Charité-Universitätsmedizin Berlin, Berlin, Germany.
Artificial Organs
|April 28, 2021
Summary
Online hemodiafiltration machines can measure absolute blood volume. Measurements after one hour of dialysis are more reproducible and precise, making them suitable for guiding ultrafiltration in patients.
Area of Science:
- Nephrology
- Medical Engineering
Background:
- Online hemodiafiltration (OL-HDF) utilizes advanced technology for enhanced dialysis treatments.
- Blood volume monitors integrated into OL-HDF machines offer potential for precise blood volume assessment.
Purpose of the Study:
- To evaluate the intra-individual reproducibility of absolute blood volume measurements using OL-HDF.
- To determine the optimal timing for accurate blood volume assessment during dialysis.
Main Methods:
- Ten patients undergoing OL-HDF were studied.
- Absolute blood volume was measured at hourly intervals within a single dialysis session.
- Statistical analysis was performed to assess the reproducibility of measurements.
Main Results:
- Absolute blood volumes differed significantly at the start versus one hour into dialysis (80.6 ± 14.5 vs. 63.9 ± 14.3 mL/kg, P < .001).
- Measurements taken after the first hour demonstrated high reproducibility (63.9 ± 14.3, 61.4 ± 13.8, and 60.9 ± 13.9 mL/kg, P = n.s.).
- Blood volume measurement accuracy improved after one hour of treatment.
Conclusions:
- Absolute blood volume measurement via OL-HDF is reproducible after the initial hour of dialysis.
- Measurements obtained one hour post-initiation are more precise than earlier measurements.
- This method may be valuable for guiding ultrafiltration strategies in clinical practice.
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