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Abstract: TH-PO184

Calculation of Extracellular Fluid Volume from Regular Blood Test Results of Patients Undergoing Hemodialysis

Session Information

Category: Dialysis

  • 701 Dialysis: Hemodialysis and Frequent Dialysis


  • Nakai, Shigeru, Fujita Health University School of Health Scieneces, Toyoake, Aichi, Japan
  • Shibata, Kazuhiko, Yokohama Minami Clinic, Yokohama, Japan
  • Masakane, Ikuto, Honcho-Yabuki Clinic, Yamagata, Japan
  • Ito, Takahito, Kataguilli Medical Center, Shibata, Japan
  • Matsuoka, Teppei, taiseikai medical corporation, ogaki-city Gifu pref., Japan
  • Aoki, Takeshi, Nagoya Municipal Industrial Research Institute, Iwakura-shi, Aichi-ken, Japan
  • Shinzato, Takahiro, Daiko Medical Engineering Research Institute, Nagoya-shi,, Japan
  • Hayashi, Hiroki, Fujita Health University School of Medicine, Aichi, Japan
  • Tsuboi, Naotake, Fujita Health University School of Medicine, Aichi, Japan
  • Hasegawa, Midori, Fujita Health University School of Medicine, Aichi, Japan
  • Inaguma, Daijo, Fujita Health University School of Medicine, Aichi, Japan
  • Yuzawa, Yukio, Fujita Health University School of Medicine, Aichi, Japan
  • Ookawara, Susumu, Saitama Medical Center, Jichi Medical University, Saitama-city, Japan

Uric acid (UA) is a solute that cannot cross cell membranes in the general tissues via simple diffusion, facilitated diffusion, or active transport, indicating that the UA distribution volume (UDiV) is equal to the extracellular fluid volume (ECFV). At ASN 2018, we reported that UDiV is closely correlated with ECFV predicted using the bioimpedance method (BIA-ECFV); however, whether UDiV is a useful tool for distinguishing different hydration statuses remains unclear.


We compared UDiV calculated from regular blood test results with BIA-ECFV of 53 patients undergoing hemodialysis (HD) predicted using BCM (Fresenius Medical Care). Further, we compared UDiV normalized with the post-HD body weight (nUDiV) in nine patients with pedal edema (overhydrated patients), five with intradialytic hypotension (underhydrated patients), and 24 without any clinical symptoms relating to hydration status (symptom-free patients).


We observed a significant correlation between UDiV (x) and BIA-ECFV (y) (y = 0.69x + 3.25; r-square = 0.61; p < 0.0001). The regression line substantially coincided with the line of identity. Bland-Altman analysis showed a systematic error for UDiV versus BIA-ECFV. In addition, we found a significant difference between UDiV and BIA-ECFV (mean difference = 0.94 L; 95% CI = 0.37-1.52 L). As shown in the figure, the nUDiV could help distinguish different hydration statuses.


UDiV is a plausible alternative marker of BIA-ECFV for the assessment of the hydration statuses of HD patients.

nUDiV and hydration statuses