Toward the optimal dose metric in continuous renal replacement therapy.

Abstract

PURPOSE:

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.

• Authors: Rolando Claure-Del Granado, Etienne Macedo, Glenn M Chertow, Sharon Soroko, Jonathan Himmelfarb, T Alp Ikizler, Emil P Paganini, Ravindra L Mehta
• Journal: The International journal of artificial organs (Int J Artif Organs) Vol. 35 Issue 6 Pg. 413-24 (Jun 2012) ISSN: 1724-6040 [Electronic] United States
• PMID: 22466995 (Publication Type: Comparative Study, Journal Article, Multicenter Study, Research Support, N.I.H., Extramural)

Chemical References

• Biomarkers
• Dialysis Solutions
• Membranes, Artificial
• Urea
• Creatinine

Topics

• Acute Kidney Injury (blood, physiopathology, therapy)
• Adult
• Biomarkers (blood)
• Blood Urea Nitrogen
• Creatinine (blood)
• Critical Illness
• Dialysis Solutions (administration & dosage, metabolism)
• Equipment Design
• Female
• Humans
• Kinetics
• Male
• Membranes, Artificial
• Middle Aged
• Models, Biological
• Renal Dialysis (instrumentation, methods)
• Treatment Outcome
• United States
• Urea (blood)
• Urination