title: Etanercept clearance during an in vitro model of continuous venovenous hemofiltration.
abstract: OBJECTIVE
  Etanercept is a tumor necrosis factor-alpha antagonist used in inflammation-mediated conditions. Continuous venovenous hemofiltration (CVVH) has also been used in patients with inflammatory conditions. This study evaluated etanercept clearance using an in vitro CVVH model.
  
  
  METHODS
  Etanercept clearance was assessed in vitro in bovine blood at 1-3 mg/l final serum concentration, and urea control at 750 mg/l. CVVH was performed using polyacrylonitrile, polysulfone, and polymethylmethacrylate filters at 3 l/h ultrafiltrate and 200 ml/min blood flow rates. Transmembrane clearance was estimated using sieving coefficient calculations, and adsorptive removal rate was approximated using a mass balance calculation.
  
  
  RESULTS
  Urea sieving coefficient remained constant (1.04 +/- 0.01). Ultrafiltrate etanercept concentrations were undetectable (sieving coefficient < 0.02) and transmembrane and adsorptive clearances were negligible.
  
  
  CONCLUSIONS
  Etanercept is not cleared appreciably by transmembrane or adsorptive mechanisms in CVVH using polyacrylonitrile, polysulfone, or polymethylmethacrylate hemofilters.
authors.affiliation: Department of Pediatrics, Division of Critical Care, Monroe Carell Jr. Children's Hospital at Vanderbilt, Vanderbilt University, Nashville, Tenn. 37232-3467, USA. geoffrey.fleming@vanderbilt.edu
authors.forename: Geoffrey M
authors.initials: GM
authors.lastname: Fleming
authors.forename: Noha N
authors.initials: NN
authors.lastname: Salama
authors.forename: Saada K
authors.initials: SK
authors.lastname: Eid
authors.forename: Kenneth R
authors.initials: KR
authors.lastname: Cooke
authors.forename: Bruce A
authors.initials: BA
authors.lastname: Mueller
mesh_terms: D000180:Acrylic Resins; D000327:Adsorption; D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000493:pharmacokinetics*; D002417:Cattle; D000068800:Etanercept; D006440:Hemofiltration / Q000379:methods*; D007074:Immunoglobulin G / Q000494:pharmacology*; D008567:Membranes, Artificial; D008657:Metabolic Clearance Rate; D008954:Models, Biological; D011108:Polymers; D019904:Polymethyl Methacrylate; D018124:Receptors, Tumor Necrosis Factor; D013450:Sulfones
chemical_list: D000180:Acrylic Resins; D000894:Anti-Inflammatory Agents, Non-Steroidal; D007074:Immunoglobulin G; D008567:Membranes, Artificial; D011108:Polymers; D018124:Receptors, Tumor Necrosis Factor; D013450:Sulfones; C010504:polyacrylonitrile; C017662:polysulfone P 1700; D019904:Polymethyl Methacrylate; D000068800:Etanercept