title: Toward the optimal dose metric in continuous renal replacement therapy.
abstract: OBJECTIVE
  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.affiliation: University of California San Diego, San Diego, California - USA.
authors.forename: Rolando
authors.initials: R
authors.lastname: Claure-Del Granado
authors.forename: Etienne
authors.initials: E
authors.lastname: Macedo
authors.forename: Glenn M
authors.initials: GM
authors.lastname: Chertow
authors.forename: Sharon
authors.initials: S
authors.lastname: Soroko
authors.forename: Jonathan
authors.initials: J
authors.lastname: Himmelfarb
authors.forename: T Alp
authors.initials: TA
authors.lastname: Ikizler
authors.forename: Emil P
authors.initials: EP
authors.lastname: Paganini
authors.forename: Ravindra L
authors.initials: RL
authors.lastname: Mehta
mesh_terms: D058186:Acute Kidney Injury / Q000097:blood / Q000503:physiopathology / Q000628:therapy*; D000328:Adult; D015415:Biomarkers / Q000097:blood; D001806:Blood Urea Nitrogen; D003404:Creatinine / Q000097:blood; D016638:Critical Illness; D015314:Dialysis Solutions / Q000008:administration & dosage* / Q000378:metabolism; D004867:Equipment Design; D005260:Female; D006801:Humans; D007700:Kinetics; D008297:Male; D008567:Membranes, Artificial; D008875:Middle Aged; D008954:Models, Biological; D006435:Renal Dialysis / Q000295:instrumentation / Q000379:methods*; D016896:Treatment Outcome; D014481:United States; D014508:Urea / Q000097:blood; D014554:Urination
chemical_list: D015415:Biomarkers; D015314:Dialysis Solutions; D008567:Membranes, Artificial; D014508:Urea; D003404:Creatinine