Abstract: SA-PO754

Control of Uremic Solute Levels in Smaller Pediatric Hemodialysis Patients

Session Information

Category: Dialysis

  • 601 Standard Hemodialysis for ESRD

Authors

  • O Brien, Frank J., Stanford University/VAMC Nephrology, Palo Alto, Alabama, United States
  • Fung, Enrica, Stanford University/VAMC Nephrology, Palo Alto, Alabama, United States
  • Plummer, Natalie, Stanford University/VAMC Nephrology, Palo Alto, Alabama, United States
  • Meyer, Timothy W., Stanford University/VAMC Nephrology, Palo Alto, Alabama, United States
  • Brakeman, Paul R., UCSF, San Francisco, California, United States
  • Sutherland, Scott M., Stanford University, Palo Alto, California, United States
  • Sirich, Tammy L., Stanford University/VAMC Nephrology, Palo Alto, Alabama, United States
Background

Current guidelines for hemodialysis (HD) in pediatric patients are adapted from those for adults, and dialysis is prescribed proportional to urea's distribution volume to achieve a target Kt/Vurea. Dosing HD proportional to volume in smaller patients, however, has been questioned. Uremic waste solutes may be produced in proportion to metabolic rate, may be more nearly proportional to body surface area (BSA) than volume. As body size decreases, the ratio of BSA to volume increases. Plasma levels of uremic solutes may thus remain higher in smaller patients when dialysis is prescribed proportional to volume. We tested this hypothesis by measuring plasma levels of pseudouridine (PU), a uremic waste solute whose generation is proportional to BSA, in pediatric dialysis patients.

Methods

PU and urea nitrogen (UN) were measured in plasma and dialysate obtained at the midweek session in 19 pediatric patients with BSA from 0.64 to 1.88 m2 receiving thrice weekly HD.

Results

The dialytic clearance (Kd) of PU was proportional to that of UN (KdPU/KdUN 0.83±0.06, R2 0.95, p<0.001). As expected, the generation of PU assessed by PU recovery in the dialysate was proportional to BSA (189±45 µmol/day/m2, R2 0.70, p <0.001). spKt/V was well maintained averaging 1.55±0.24 and did not vary over the range of BSA values. As shown in the figure, however, the pre-treatment plasma PU level was significantly higher in the patients with lower BSA (p <0.05).

Conclusion

Dosing HD by volume may leave uremic solutes at higher levels in smaller pediatric patients. Further studies are needed to determine whether prescription of HD based on BSA provides clinical benefit.

Pre treatment pseudouridine levels vs. Body Surface Area

Funding

  • Veterans Affairs Support