There is no consensus on the optimal method to measure delivered dialysis dose in patients with acute kidney injury (AKI). The use of direct dialysate-side quantification of dose in preference to the use of formal blood-based urea kinetic modeling and simplified blood urea nitrogen (BUN) methods has been recommended for dose assessment in critically-ill patients with AKI. We evaluate six different blood-side and dialysate-side methods for dose quantification.
Methods:
We examined data from 52 critically-ill patients with AKI requiring dialysis. All patients were treated with pre-dilution CVVHDF and regional citrate anticoagulation. Delivered dose was calculated using blood-side and dialysis-side kinetics. Filter function was assessed during the entire course of therapy by calculating BUN to dialysis fluid urea nitrogen (FUN) ratios q/12 hours.
Results:
Median daily treatment time was 1,413 min (1,260–1,440). The median observed effluent volume per treatment was 2,355 mL/h (2,060–2,863) (p<0.001). Urea mass removal rate was 13.0±7.6 mg/min. Both EKR (r2=0.250; p<0.001) and KD (r2=0.409; p<0.001) showed a good correlation with actual solute removal. EKR and KD presented a decline in their values that was related to the decrease in filter function assessed by the FUN/BUN ratio.
Conclusions:
Effluent rate (mL/kg/h) can only empirically provide an estimated of dose in CRRT. For clinical practice, we recommend that the delivered dose should be measured and expressed as KD. EKR also constitutes a good method for dose comparisons over time and across modalities.
CasinoF.G., LopezT.. The equivalent renal urea clearance: a new parameter to assess dialysis dose.Nephrol Dial Transplant.1996; 11(8): 1574–1581.
3.
RoncoC., BellomoR., HomelP.Effects of different doses in continuous veno-venous haemofiltration on outcomes of acute renal failure: a prospective randomised trial.Lancet.2000; 356(9223): 26–30. Medline. doi: 10.1016/S0140-6736(00)02430-2
4.
SchifflH., LangS.M., FischerR.. Daily hemodialysis and the outcome of acute renal failure.N Engl J Med.2002; 346(5): 305–310. Medline. doi: 10.1056/NEJMoa010877
5.
TolwaniA.J., CampbellR.C., StofanB.S., LaiK.R., OsterR.A., WilleK.M.. Standard versus high-dose CVVHDF for ICU-related acute renal failure.J Am Soc Nephrol.2008; 19(6): 1233–1238. Medline. doi: 10.1681/ASN.2007111173
6.
VA/NIH Acute Renal Failure Trial Network, et al.Intensity of renal support in critically ill patients with acute kidney injury.N Engl J Med.2008; 359(1): 7–20. Medline. doi: 10.1056/NEJ-Moa0802639
7.
VesconiS., CruzD.N., FumagalliR.Delivered dose of renal replacement therapy and mortality in critically ill patients with acute kidney injury.Crit Care.2009; 13(2): R57. Medline. doi: 10.1186/cc7784
8.
ClarkW.R., MuellerB.A., KrausM.A., MaciasW.L.. Dialysis prescription and kinetics in acute renal failure.Adv Ren Replace Ther.1997; 4(2)(Suppl 1): 64–71.
9.
EvansonJ.A., IkizlerT.A., WingardR.Measurement of the delivery of dialysis in acute renal failure.Kidney Int.1999; 55(4): 1501–1508. Medline. doi: 10.1046/j.1523-1755.1999.00355.x
10.
KeshaviahP.. The solute removal index–a unified basis for comparing disparate therapies.Perit Dial Int.1995; 15(2): 101–104.
11.
MehtaR.L., PascualM.T., SorokoS.Spectrum of acute renal failure in the intensive care unit: the PICARD experience.Kidney Int.2004; 66(4): 1613–1621. Medline. doi: 10.1111/j.1523-1755.2004.00927.x
12.
MehtaR.L.. Continuous renal replacement therapy in the critically ill patient.Kidney Int.2005; 67(2): 781–795. Medline. doi: 10.1111/j.1523-1755.2005.67140.x
EvansonJ.A., HimmelfarbJ., WingardR.Prescribed versus delivered dialysis in acute renal failure patients.Am J Kidney Dis.1998; 32(5): 731–738. Medline. doi: 10.1016/S0272-6386(98)70127-1
15.
RatanaratR., PermpikulC., RoncoC.. Renal replacement therapy in acute renal failure: which index is best for dialysis dose quantification?Int J Artif Organs.2007; 30(3): 235–243. Medline.
16.
LeblancM., GarredL.J., CardinalJ.Catabolism in critical illness: estimation from urea nitrogen appearance and creatinine production during continuous renal replacement therapy.Am J Kidney Dis.1998; 32(3): 444–453. Medline. doi: 10.1053/ajkd.1998.v32.pm9740161
17.
MarshallM.R.. Current status of dosing and quantification of acute renal replacement therapy. Part 1: mechanisms and consequences of therapy under-delivery.Nephrology (Carlton).2006; 11(3): 171–180. Medline. doi: 10.1111/j.1440-1797.2006.00572.x
18.
BoumanC.S., Oudemans-Van StraatenH.M., TijssenJ.G., ZandstraD.F., KeseciogluJ.. Effects of early high-volume continuous venovenous hemofiltration on survival and recovery of renal function in intensive care patients with acute renal failure: a prospective, randomized trial.Crit Care Med.2002; 30(10): 2205–2211. Medline. doi: 10.1097/00003246-200210000-00005
19.
SaudanP., NiederbergerM., De SeigneuxS.Adding a dialysis dose to continuous hemofiltration increases survival in patients with acute renal failure.Kidney Int.2006; 70(7): 1312–1317. Medline. doi: 10.1038/sj.ki.5001705
20.
RENAL Replacement Therapy Study Investigators, et al.Intensity of continuous renal-replacement therapy in critically ill patients.N Engl J Med.2009; 361(17): 1627–1638. Medline. doi: 10.1056/NEJMoa0902413
21.
PaganiniE.P.. Dialysis is not dialysis is not dialysis! Acute dialysis is different and needs help!Am J Kidney Dis.1998; 32(5): 832–833. Medline. doi: 10.1016/S0272-6386(98)70142-8
Claure-Del GranadoR., MacedoE., ChertowG.M.Effluent Volume in Continuous Renal Replacement Therapy Overestimates the Delivered Dose of Dialysis.Clin J Am Soc Nephrol.2011; 6: 467–475. Medline. doi: 10.2215/CJN.02500310
24.
VenkataramanR., KellumJ.A., PalevskyP.. Dosing patterns for continuous renal replacement therapy at a large academic medical center in the United States.J Crit Care.2002; 17(4): 246–250. Medline. doi: 10.1053/jcrc.2002.36757
25.
UchinoS., FealyN., BaldwinI., MorimatsuH., BellomoR.. Continuous is not continuous: the incidence and impact of circuit “down-time” on uraemic control during continuous veno-venous haemofiltration.Intensive Care Med.2003; 29(4): 575–578.
26.
HimmelfarbJ., EvansonJ., HakimR.M., FreedmanS., ShyrY., IkizlerT.A.. Urea volume of distribution exceeds total body water in patients with acute renal failure.Kidney Int.2002; 61(1): 317–323. Medline. doi: 10.1046/j.1523–1755.2002.00118.x
MarshallM.R.. Current status of dosing and quantification of acute renal replacement therapy. Part 2: dosing paradigms and clinical implementation.Nephrology (Carlton).2006; 11(3): 181–191. Medline. doi: 10.1111/j.1440-1797.2006.00581.x
29.
KanagasundaramN.S., PaganiniE.P.. Critical care dialysis–a Gordian knot (but is untying the right approach?).Nephrol Dial Transplant.1999; 14(11): 2590–2594. Medline. doi: 10.1093/ndt/14.11.2590
30.
CasinoF.G., MarshallM.R.. Simple and accurate quantification of dialysis in acute renal failure patients during either urea non-steady state or treatment with irregular or continuous schedules.Nephrol Dial Transplant.2004; 19(6): 1454–1466. Medline. doi: 10.1093/ndt/gfh218
31.
CasinoF.G.. Is Kt/V Urea a Satisfactory Measure for Dosing the Newer Dialysis Regimens?Semin Dial.2001; 14(1): 18–21. Medline. doi: 10.1046/j.1525-139x.2001.00003-5.x
32.
MarshallM.R., MaT., GallerD., RankinA.P., WilliamsA.B.. Sustained low-efficiency daily diafiltration (SLEDD-f) for critically ill patients requiring renal replacement therapy: towards an adequate therapy.Nephrol Dial Transplant.2004; 19(4): 877–884. Medline. doi: 10.1093/ndt/gfg625
