Anticoagulation therapy during haemodialysis: a comparative study between two heparin regimens

Low-molecular-weight heparins have been suggested as providing well tolerated, efficient, convenient and possibly more cost-effective anticoagulation for haemodialysis than unfractionated heparins (UFHs). A single-bolus dose at the start of haemodialysis effectively prevents clot formation in the dialyser and air trap with fewer side effects and possible benefits on uraemic dyslipidaemia. The safety, clinical efficacy and cost of two anticoagulation regimens in 23 haemodialysis patients were compared over 12-month period. The study comprised two stages: the first stage in which UFH was used for 6 months and the second stage in which UFH was replaced by tinzaparin sodium. The relationship between the anticoagulant effect of tinzaparin sodium and clinical clotting during haemodialysis was recorded. Clinical clotting (grades 1-4) was evaluated by visual inspection after blood draining of the air trap every hour and by inspection of the dialyser after each session. The costs and effects of both anticoagulant protocols on the lipid profile were also compared. Anticoagulation with tinzaparin sodium resulted in less frequent dialyser and air-trap clotting compared with UFH (P = 0.001 and 0.04, respectively). Over 24 weeks, no changes in standard serum lipid profiles were observed. There was statistically significant improvement in dialysis adequacy - evidenced by improved single-pool Kt/V 6 months after tinzaparin sodium use (1.40 +/- 0.28 tinzaparin sodium versus 1.23 +/- 0.28 for UFH) without any change in the haemodialysis prescription. The total cost of 24-week use of tinzaparin sodium was 23% more expensive compared with that of UFH. Tinzaparin sodium should be considered as an effective, well tolerated and may be a superior alternative to conventional heparin anticoagulation in haemodialysis. However, at least - on the short term - tinzaparin sodium therapy did not affect lipid profile in haemodialysis patients. Currently, the direct cost in Saudi Arabia is a little more than standard heparin by about 23%.