title: New high-cutoff dialyzer allows improved middle molecule clearance without an increase in albumin loss: a clinical crossover comparison in extended dialysis.
abstract: BACKGROUND
  Accumulation of middle molecules is thought to have adverse effects in patients with acute kidney injury (AKI). Elimination of middle molecules by non-convective means, i.e. hemodialysis, remains difficult. The aim of the study was to investigate the removal characteristics of a new high permeability membrane in AKI patients undergoing extended dialysis (ED).
  
  
  METHODS
  We performed a prospective, crossover study comparing the EMiC2 dialyzer (1.8 m(2), FMC, Germany) and AV 1000S (1.8 m(2), FMC) in 11 critically ill patients with AKI. β2-Microglobulin, cystatin c, creatinine, and urea were measured before and after 0.5, 5.0 and 10 h of ED. Serum reduction ratios, dialyzer clearances, and mass in the total collected dialysate were determined.
  
  
  RESULTS
  Dialyzer clearance of β2-microglobulin (EMiC2: 52 ± 1.7 ml/min, AV 1000S: 41.7 ± 1.5 ml/min, p = 0.0002) and cystatin c (EMiC2: 47.2 ± 1.2 ml/min, AV 1000S: 34.2 ± 2.3 ml/min, p < 0.0001) was markedly different, as was the reduction of serum levels of β2-microglobulin (EMiC2: 54.3 ± 3.6%, AV 1000S: 39.1 ± 4.5%, p = 0.025) and cystatin c (EMiC2: 38.9 ± 2.6%, AV 1000S: 28.0 ± 3.9%, p = 0.043). Additionally, we observed a higher total amount of these substances in the collected dialysate. There was no significant difference in the total amount of albumin eliminated per treatment.
  
  
  CONCLUSIONS
  The new EMiC2 dialyzer enhances removal of middle molecules without an increase in albumin loss. The clinical relevance of this finding needs to be determined.
authors.affiliation: Division of Nephrology and Hypertension, Department of Internal Medicine, Medical School Hannover, Hannover, Germany.
authors.forename: Julius J
authors.initials: JJ
authors.lastname: Schmidt
authors.forename: Carsten
authors.initials: C
authors.lastname: Hafer
authors.forename: Christian
authors.initials: C
authors.lastname: Clajus
authors.forename: Johannes
authors.initials: J
authors.lastname: Hadem
authors.forename: Gernot
authors.initials: G
authors.lastname: Beutel
authors.forename: Bernhard M W
authors.initials: BM
authors.lastname: Schmidt
authors.forename: Jan T
authors.initials: JT
authors.lastname: Kielstein
mesh_terms: D018806:APACHE; D058186:Acute Kidney Injury / Q000097:blood* / Q000628:therapy*; D000328:Adult; D003404:Creatinine / Q000097:blood; D018592:Cross-Over Studies; D055316:Cystatin C / Q000097:blood; D005260:Female; D017583:Hemodiafiltration / Q000295:instrumentation* / Q000379:methods / Q000592:standards*; D006801:Humans; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D012015:Reference Standards; D012709:Serum Albumin / Q000378:metabolism*; D014508:Urea / Q000097:blood; D001613:beta 2-Microglobulin / Q000097:blood
chemical_list: D055316:Cystatin C; D012709:Serum Albumin; D001613:beta 2-Microglobulin; D014508:Urea; D003404:Creatinine