title: Effect of hematocrit on dialyzer urea and creatinine clearance indices in a hemodialysis patient with erythrocytosis.
abstract: The association between azotemic index dialyzer clearances and hematocrit was investigated in a 63-year-old dialysis-dependent man with acquired renal cysts. During 43 months of hemodialysis, hematocrit rose from 27.3 to 65.0 vol%, as a consequence of high serum erythropoietin levels. Concomitantly, dry weight also increased from 116.8 to 140.8 kg. Both hematocrit and dry weight correlated with: (a) urea reduction ratio, (b) creatinine reduction ratio (CRR), and (c) KT/V urea. All correlations were negative. Stepwise regression showed that only hematocrit was an independent correlate of the CRR (CRR = 0.662 - 007* Hct, R2 = 0.770); whereas, both hematocrit (Hct) and weight (W) were independent correlates of KT/V urea (KT/V = 2.070 - 0.005*Hct - 0.009*W,R2 = 0.721). In addition to creatinine clearance, urea clearance through the dialyzer is reduced by a rising hematocrit. The effect of hematocrit on urea clearance is relatively small. Therefore, it requires large changes in hematocrit in order to be detected.
authors.affiliation: Renal Section, Veterans Affairs Medical Center, Albuquerque, New Mexico, USA.
authors.forename: A C
authors.initials: AC
authors.lastname: Nwosu
authors.forename: A H
authors.initials: AH
authors.lastname: Tzamaloukas
authors.forename: D
authors.initials: D
authors.lastname: Malhotra
authors.forename: M C
authors.initials: MC
authors.lastname: Saddler
authors.forename: G H
authors.initials: GH
authors.lastname: Murata
mesh_terms: D003404:Creatinine / Q000652:urine*; D004921:Erythropoietin / Q000097:blood; D006400:Hematocrit; D006801:Humans; D052177:Kidney Diseases, Cystic / Q000150:complications / Q000628:therapy; D008297:Male; D008875:Middle Aged; D011086:Polycythemia / Q000209:etiology / Q000503:physiopathology*; D012044:Regression Analysis; D006435:Renal Dialysis; D014508:Urea / Q000652:urine*
chemical_list: D004921:Erythropoietin; D014508:Urea; D003404:Creatinine