title: Iohexol transmembrane clearance during modeled continuous renal replacement therapy.
abstract: OBJECTIVE
  Urea clearance during continuous renal replacement therapy (CRRT) is not representative of middle molecular weight solute clearances. We aimed to characterize iohexol, molecular weight 821 Da, clearance during continuous hemofiltration (CH) and continuous hemodialysis (CHD).
  
  
  METHODS
  Using an in vitro model, iohexol sieving coefficients (SC) and saturation coefficients (SA) were determined with the M100 membrane at ultrafiltration/dialysate rates of 1, 2, 3, 4, and 6 l/h. Iohexol transmembrane clearance was calculated using the measured SC and SA.
  
  
  RESULTS
  During CH, the value of iohexol SC remained approximately 1 at all ultrafiltration rates studied. In contrast, during CHD iohexol the mean SA was 1.02 ± 0.05 at a dialysate rate 1 l/h and decreased significantly with higher dialysate rates to a mean SA of 0.57 ± 0.12 at a dialysate rate of 6 l/h.
  
  
  CONCLUSIONS
  At higher effluent flow rates, CH was more effective in removing iohexol than CHD. CH transmembrane clearance of iohexol appears to approximate the ultrafiltration rate.
authors.forename: J Michael
authors.initials: JM
authors.lastname: Yardman-Frank
authors.forename: Renee-Claude
authors.initials: RC
authors.lastname: Mercier
authors.forename: Craig S
authors.initials: CS
authors.lastname: Wong
authors.forename: A Mary
authors.initials: AM
authors.lastname: Vilay
mesh_terms: D000818:Animals; D002417:Cattle; D003287:Contrast Media / Q000378:metabolism*; D015314:Dialysis Solutions / Q000737:chemistry; D006440:Hemofiltration / Q000379:methods*; D018056:Hemorheology; D006801:Humans; D007472:Iohexol / Q000378:metabolism*; D007700:Kinetics; D008567:Membranes, Artificial; D008954:Models, Biological; D006435:Renal Dialysis / Q000379:methods*; D014462:Ultrafiltration; D014508:Urea / Q000097:blood
chemical_list: D003287:Contrast Media; D015314:Dialysis Solutions; D008567:Membranes, Artificial; D007472:Iohexol; D014508:Urea