title: Where and When To Inject Low Molecular Weight Heparin in Hemodiafiltration? A Cross Over Randomised Trial.
abstract: OBJECTIVE
  Low molecular weight heparins (LMWHs) are small enough to pass large pore dialysis membranes. Removal of LMWH if injected before the start of the session is possible during high-flux dialysis and hemodiafiltration. The aim of this study was to determine the optimal mode (place and time) of tinzaparin administration during postdilution hemodiafiltration.
  In 13 chronic hemodiafiltration patients, 3 approaches of injection were compared in a randomised cross over trial: i) before the start of the session at the inlet blood line filled with rinsing solution (IN0), ii) 5 min after the start at the inlet line filled with blood (IN5) and iii) before the start of the session at the outlet blood line (OUT0). Anti-Xa activity, thrombin generation, visual clotting score and reduction ratios of urea and beta2microglobulin were measured.
  
  
  RESULTS
  Anti-Xa activity was lower with IN0 compared with IN5 and OUT0, and also more thrombin generation was observed with IN0. No differences were observed in visual clotting scores and no clinically relevant differences were observed in solute reduction ratio. An anti-Xa of 0.3 IU/mL was discriminative for thrombin generation. Anti-Xa levels below 0.3 IU/mL at the end of the session were associated with worse clotting scores and lower reduction ratio of urea and beta2microglobulin.
  
  
  CONCLUSIONS
  Injection of tinzaparin at the inlet line before the start of postdilution hemodiafiltration is associated with loss of anticoagulant activity and can therefore not be recommended. Additionally, we found that an anti-Xa above 0.3 IU/mL at the end of the session is associated with less clotting and higher dialysis adequacy.
  
  
  BACKGROUND
  Clinicaltrials.gov NCT00756145.
authors.affiliation: Department of Nephrology, Ghent University Hospital, Ghent, Belgium.
authors.forename: Annemieke
authors.initials: A
authors.lastname: Dhondt
authors.affiliation: Department of Nephrology, Ghent University Hospital, Ghent, Belgium.
authors.forename: Ruben
authors.initials: R
authors.lastname: Pauwels
authors.affiliation: Coagulation Laboratory, Department of Clinical Chemistry, Microbiology and Immunology, Ghent University Hospital, Ghent, Belgium.
authors.forename: Katrien
authors.initials: K
authors.lastname: Devreese
authors.affiliation: Department of Nephrology, Ghent University Hospital, Ghent, Belgium.
authors.forename: Sunny
authors.initials: S
authors.lastname: Eloot
authors.affiliation: Department of Nephrology, Ghent University Hospital, Ghent, Belgium.
authors.forename: Griet
authors.initials: G
authors.lastname: Glorieux
authors.affiliation: Department of Nephrology, Ghent University Hospital, Ghent, Belgium.
authors.forename: Raymond
authors.initials: R
authors.lastname: Vanholder
mesh_terms: D000925:Anticoagulants / Q000008:administration & dosage*; D001777:Blood Coagulation / Q000187:drug effects; D018592:Cross-Over Studies; D065427:Factor Xa Inhibitors / Q000008:administration & dosage; D005260:Female; D017583:Hemodiafiltration; D006495:Heparin, Low-Molecular-Weight / Q000008:administration & dosage*; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood* / Q000628:therapy*; D007958:Leukocyte Count; D008297:Male; D000078222:Tinzaparin; D016896:Treatment Outcome; D014508:Urea / Q000097:blood; D001613:beta 2-Microglobulin / Q000097:blood
chemical_list: D000925:Anticoagulants; D065427:Factor Xa Inhibitors; D006495:Heparin, Low-Molecular-Weight; D001613:beta 2-Microglobulin; D000078222:Tinzaparin; D014508:Urea