RESUMO
Urea kinetic parameters were studied by means of dialysate collection in 8 stable hemodialysis patients before and after treatment with recombinant human erythropoietin (r-HuEPO), in order to investigate the impact of a rising hematocrit (Ht) on dialyzer performance and nutritional status. After 6 months, the average in vivo dialyzer urea clearance had fallen from 152 to 132 ml/min and consequently Kt/V values had become undesirably low in most of the patients in whom the relatively short dialysis regimens had been kept unchanged. There was also a significant decrease of protein intake. As a result of both changes there was only a moderate increase of predialysis mean blood urea concentration. These findings indicate that after correction of anemia by r-HuEPO dialyzer performance decreased. The concomitant decrease of protein intake seems to contrast to the improved general physical condition and appetite as indicated in the questionnaires. Although body weight remained the same, there might have been a tendency to avoid protein consumption with maintained total calory intake as a result of slight underdialysis. Therefore, in individual cases dialysis prescriptions may need reconsideration when Ht levels rise after r-HuEPO administration, especially in short dialysis regimens.
