title: Prediction of iopromide reduction rates during haemodialysis using an in vitro dialysis system.
abstract: BACKGROUND
  In clinical studies, it has been difficult to evaluate the influence of haemodialysis (HD) parameters on HD clearance (CL(HD)) and reduction rate (RR) of non-ionic contrast medium during HD sessions. We therefore predicted clinical values of CL(HD) and RR of iopromide, a non-ionic contrast medium, from findings obtained from in vitro experiments, and confirmed that these predictive values were comparable with the actual values in clinical cases.
  
  
  METHODS
  We developed a correlation equation for predicting CL(HD) on the basis of in vitro HD experiments by varying blood flow rates between 100 and 200 ml/min with a cuprammonium rayon dialyser (AM-SD-10H). Total body clearance of iopromide (CL(PT)) was estimated by the Cockroft-Gault equation. The volume of distribution (V(d)) was obtained from the reported value. By using the HD and three pharmacokinetic parameters (CL(HD), CL(PT) and V(d)), we predicted CL(HD) and RR for seven patients undergoing HD after the administration of iopromide.
  
  
  RESULTS
  In the in vitro study, the mean values (+/-SD) of iopromide clearance at blood flow rates of 100, 150 and 200 ml/min were 45.35 (2.54), 53.88 (6.46) and 57.61 (4.72) ml/min, respectively. There were highly significant correlations between clearance and blood flow rate (r = 0.975). Although the predicted CL(HD) showed a tendency towards underestimation, a good correlation was found. Predicted RR values were similar to observed values except for one case.
  
  
  CONCLUSIONS
  The in vitro model used in the present study provides pertinent information about CL(HD) and is helpful for predicting RR during HD in individual patients undergoing HD.
authors.affiliation: Department of Drug Information and Communication, Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba-shi, Chiba 260-8675, Japan. tera@p.chiba-u.ac.jp
authors.forename: Tomohisa
authors.initials: T
authors.lastname: Teraoka
authors.forename: Takao
authors.initials: T
authors.lastname: Sugai
authors.forename: Sunao
authors.initials: S
authors.lastname: Nakamura
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Hirasawa
authors.forename: Shigeto
authors.initials: S
authors.lastname: Oda
authors.forename: Hidetoshi
authors.initials: H
authors.lastname: Shiga
authors.forename: Mio
authors.initials: M
authors.lastname: Suga
authors.forename: Shinji
authors.initials: S
authors.lastname: Yamane
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Ishii
authors.forename: Shin-ichi
authors.initials: S
authors.lastname: Yamagata
authors.forename: Nobunori
authors.initials: N
authors.lastname: Satoh
authors.forename: Shiro
authors.initials: S
authors.lastname: Ueda
mesh_terms: D003287:Contrast Media / Q000493:pharmacokinetics*; D005544:Forecasting; D007472:Iohexol / Q000031:analogs & derivatives* / Q000493:pharmacokinetics; D008657:Metabolic Clearance Rate; D008961:Models, Structural; D006435:Renal Dialysis
chemical_list: D003287:Contrast Media; D007472:Iohexol; C038192:iopromide