title: A significant proportion of patients treated with citrate containing dialysate need additional anticoagulation.
abstract: BACKGROUND
  The blood membrane interaction induced during hemodialysis (HD) activates the coagulation system. To prevent clotting and to maintain dialyzer patency, an anticoagulant such as tinzaparin is used. To increase patency of the dialyzers and to reduce the risk of bleeding related to anticoagulation, citrate-containing dialysate has been introduced in Europe.
  
  
  OBJECTIVE
  The aim of this randomized, cross-over study was to investigate if citrate-containing dialysate was safe and efficient enough as the sole anticoagulation agent in chronic HD patients.
  
  
  METHODS
  In this clinical setting, 23 patients on chronic hemodialysis were randomized in a cross-over design using anticoagulation either by LMWH-tinzaparin or citrate (Cit) as dialysate  (22 completed the study). The study included paired analyses of subjective patency, ionized calcium (iCa), urea reduction rate.  During Cit-HD, the iCa was significantly more reduced with prolonged time. The lowest iCa measured was 0.96 mmol/l. The median iCa after 210 min of HD was 1.02 for Cit-Hd and 1.16 for standard tinzaparin-HD (p = 0.001). Patency of dialyzers was estimated as clear in 14%, stripes of clotted fibers in 36%, and a red filter in 32% of HD session. The addition of approximately 40% of the patients' usual dose of tinzaparin was given to 7 of the patients as a bolus. Four Cit-HD sessions had to be interrupted prematurely due to clotting.
  
  
  CONCLUSIONS
  A significant proportion of patients treated with citrate-containing dialysate need additional anticoagulation.
authors.affiliation: Department of Public Health and Medicine, Internal Medicine, Umeå University, 901 85 Umeå, Sweden. bernd.stegmayr@medicin.umu.se
authors.forename: Bernd G
authors.initials: BG
authors.lastname: Stegmayr
authors.forename: Per
authors.initials: P
authors.lastname: Jonsson
authors.forename: Dana
authors.initials: D
authors.lastname: Mahmood
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000009:adverse effects / Q000627:therapeutic use*; D001777:Blood Coagulation / Q000187:drug effects*; D019343:Citric Acid / Q000009:adverse effects / Q000627:therapeutic use*; D018592:Cross-Over Studies; D015314:Dialysis Solutions / Q000009:adverse effects / Q000627:therapeutic use*; D005260:Female; D006470:Hemorrhage / Q000139:chemically induced; D006495:Heparin, Low-Molecular-Weight / Q000009:adverse effects / Q000627:therapeutic use*; D006801:Humans; D007674:Kidney Diseases / Q000097:blood / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D006435:Renal Dialysis / Q000009:adverse effects; D013548:Sweden; D000078222:Tinzaparin; D055815:Young Adult
chemical_list: D000925:Anticoagulants; D015314:Dialysis Solutions; D006495:Heparin, Low-Molecular-Weight; D019343:Citric Acid; D000078222:Tinzaparin