Abstract: FR-OR051

Determinants of Interdialytic Volume Overload During More Frequent Hemodialysis: Time-Integrated Estimate of Fluid Load (TIFL)

Session Information

  • Home Hemodialysis
    November 03, 2017 | Location: Room 295, Morial Convention Center
    Abstract Time: 05:06 PM - 05:18 PM

Category: Dialysis

  • 604 Home and Frequent Dialysis


  • Leypoldt, J. Ken, None, San Clemente, California, United States
  • Collins, Allan J., Chronic Disease Research Group, Minneapolis, Minnesota, United States
  • Weinhandl, Eric D., NxStage Medical, Inc., Victoria, Minnesota, United States

The Frequent Hemodialysis Network has recently demonstrated that a novel measure of interdialytic volume overload, the time-integrated estimate of fluid load (TIFL), is inversely associated with left ventricular mass reduction and could therefore be used to evaluate the effect of volume overload on cardiac stress (Raimann et al, Blood Purif 2016). The relative importance of clinical factors, such as dietary sodium intake (NaI), interdialytic weight gain (IDWG) and dialysate sodium concentration (dialNa), on TIFL during conventional and more frequent hemodialysis (HD) are incompletely understood.


We compared the effect of clinical factors on the mean interdialytic excess of extracellular fluid volume (eECV) and TIFL using mathematical model simulations. A conventional model of sodium and fluid kinetics was used to simulate intradialytic and interdialytic changes in serum sodium and extracellular fluid volume (Kimura & Gotch, Int J Artif Organs 1984). TIFL was calculated using the approach of Raimann et al (Blood Purif 2016) that assumes rapid post-dialysis fluid intake to maintain the sodium set-point and accounts for the length of the interdialytic interval. Residual kidney urine volume was assumed negligible. We compared eECV and TIFL for conventional HD, daily HD and nocturnal HD.


As expected, eECV and TIFL were strongly and positively associated with IDWG. In contrast, eECV and TIFL were inversely associated with NaI when not accompanied by increased IDWG. The effects of treatment modality and dialNa are tabulated.


More frequent (daily and nocturnal) HD result in substantial reductions in eECV and TIFL. Similar reductions in these measures cannot be achieved with reductions in dietary Na intake or dialysate Na concentrations. The use of increased HD frequency for reduction of interdialytic fluid overload should be preferred over stringent dietary Na restriction or reductions in dialysate Na concentration.

HDTreatments/wkTreatment Time (min)dialNa (meq/L)eECV (L)TIFL (L-days)


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