Abstract: FR-PO816

Measured versus Prescribed Dialysate Sodium Using Dialysis Machines from Different Manufacturers

Session Information

Category: Dialysis

  • 601 Standard Hemodialysis for ESRD


  • Gul, Ambreen, DCI, Albuquerque, New Mexico, United States
  • Miskulin, Dana, Tufts Medical Center, Sommerville, Massachusetts, United States
  • Harford, Antonia, UNM, Albuquerque, New Mexico, United States
  • Schrader, R., DCI, Albuquerque, New Mexico, United States
  • Paine, S., DCI, Albuquerque, New Mexico, United States
  • Bender, Walter L, Dialysis Clinic Inc., Kansas City, Missouri, United States
  • Thajudeen, Bijin, University of Arizona, Tucson, Arizona, United States
  • Zager, Philip, UNM, Albuquerque, New Mexico, United States

The optimal dialysate sodium (DNa) is unknown. We previously reported that differences (measured - prescribed DNa) in facilities using Fresenius and Gambro machines ranged from +13 mEq/L to - 6 mEq/L (mean + 2.5 mEq/L), which may contribute to the disparate results of published studies. We extended these observations by assessing differences in facilities using B. Braun machines.


We studied 2 DCI facilities that use B.Braun Dialog+ machines with either NaturaLyte or Diasol dialysate. Technicians entered DNa orders into the machine, which were verified by a nurse. We turned on dialysate machines ≥ 30 minutes prior to sampling. We clamped the saline line and sampled dialysate from the dialysate port 10 minutes prior to the start of dialysis in clinics 5 (24 machines, 97 treatments) and 6 (25 machines, 54 treatments). We sampled dialysate 10 minutes prior to end of dialysis in clinics 5 (n=91) and 6 (n=54). The DCI lab measured DNa concentrations with an indirect ion selective electrode. We assessed the differences (measured- prescribed DNa) by computing least square means with a linear mixed model that accounted for random machine effects and repeated measures.


Measured DNa was 3.36 mEq/L (95% CI 2.69 – 4.02) and 1.82 mEq/L (95% CI 1.08 – 2.56) higher than prescribed in Units 5 and 6, respectively. The percentages of DNa measurements within 2 mEq/L of that ordered were 22.2% and 59.5% in Unit 5 & 6, respectively. DNa in late in dialysis was also higher than prescribed in clinics 5 (4.14 mEq/L [ 95% CI 3.54 – 4.73]) and 6 (1.81 mEq/L, [95% CI 1.15 – 2.47]). Measured DNa in samples drawn pre- and late- dialysis were similar. In clinic 5 26 pairs (28.6%) matched and 67 (73.6%) were within 1mEq/L. Corresponding numbers in clinic 6 were 22 (40.7%) and 47 (87%). The weighted kappa was 0.63 indicating good agreement between pre- and late dialysis DNa.


Measured DNa is higher than prescribed with Fresenius, Gambro, and B.Braun machines. QAPI programs should incorporate measurements of DNa to ensure adherence to the dialysis prescription.