Aluminium kinetics during haemodialysis with the Redy 2000 Sorbsystem

Aluminium kinetics of the Redy 2000 Sorbsystem using D3260 cartridges and the latest pre-treatment protocol have been studied in vitro and in vivo. In 7 patients, aluminium kinetics were studied during haemodialysis using the Redy 2000 Sorbysystem, D3260 cartridges. S557 acetate concentrate and Gambro hollow fibre dialyser (cuprophane 120M). The same patients were also studied during conventional haemodialysis using the Gambro AK10 proportionating system with acetate dialysate and Gambro hollow fibre dialyser (cuprophane 120M). There was no significant rise in plasma aluminium concentration during dialysis on the Redy 2000 Sorbsystem. The post-dialysis plasma aluminium concentrations were significantly higher after conventional haemodialysis, however, and the explanation for this is not clear but is not accounted for by differences in the degree of ultrafiltration during the studies. A significant rise in dialysate aluminium concentration was observed after 4 hours of dialysis on the Redy 2000 Sorbsystem. The manufacturer's ammonia test papers appear to be too insensitive as indicators of cartridge exhaustion and dialysate pH may be better. The D3260 cartridges should be used for a maximum of 4 hours only. Further long-term studies of aluminium kinetics using this system are justified.