Impact of targeting Kt instead of Kt/V.

Background: Patients must receive an adequate dialysis dose in each hemodialysis (HD) session. Ionic dialysance (ID) enables the dialysis dose to be monitored in each session. The aim of this study was to compare the achievement of Kt versus eKt/V values and to analyse the main impediments to reaching the dialysis dose.

Methods: Of 5316 patients from 54 Fresenius Medical Care centers in Spain undergoing their usual HD regime, 3275 received ID and were included in the study.

Results: The minimum prescribed dose of eKt/V was reached in 91.2% of the patients, while the minimum recommended dose of Kt was reached in only 66.8%. Patients not receiving the minimum Kt dose were older, had spent 7 months less on dialysis, had a dialysis duration of 6 min less, had 5.7 kg more of body weight and Qb was 47 mL/min lower. The target Kt was not reached by 62% of patients with catheters and by 37% of women. With each quintile increase of body weight, eKt/V decreased and Kt increased. Of patients with a body weight >80 kg, 1.4%, mostly men, reached the target Kt but not prescribed eKt/V.

Conclusions: The impact of monitoring the dose with Kt instead of Kt/V is that identifies 25.8% of patients who did not reach the minimum Kt while achieving Kt/V. The main impediments to achieving an adequate dialysis dose were catheter use, female sex, advanced age, greater body weight, shorter dialysis time and lower Qb.