[Kt calculation as a quality indicator of haemodialysis adequacy]. / Cálculo del Kt como indicador de calidad en el área de adecuación en hemodiálisis.

The haemodialysis dose is a good marker of dialysis adequacy, and we usually monitor it with Kt/V measure. The dialysis dose monitored with Kt allows a better discrimination, detecting a percentage of the patients that perhaps do not get an adequate dose for their gender or body surface area after treatment with a minimum recommended dose of Kt/V. The objective of this study was to evaluate Kt as a clinical indicator referred to dialysis adequacy in the haemodialysis population. The aim was that more than 85% of the patients would achieve the recommended Kt target for their gender (at least 50 litres in men and 45 litres in women), or their body surface area. In each of the patients (mean 129) the Kt mean value was determined for three consecutive dialysis sessions, one every two months, during the follow-up period (14 months). At the beginning, the Kt/V value was on target (> 1.3) in 93.2% of the patients, but only in 58% according to Kt measure for their gender. After 4 months, we observed that 85% of patients' Kt target increased for their gender, but only 68% did if we used the Kt individualised for their body surface area. From month 6 to the end of the follow-up period, more than 85% of patients obtained an adequate Kt for their body surface area (p < 0.001). A significant increase of Kt mean (5.4 litres) was observed at the end of the study (p < 0.001). The usual dialysis prescription parameters were modified increasing blood flow rate (34.14 ml/min, p < 0.001), session effective duration (8.04 minutes, p < 0.001), dialyser surface area (24.1% of patients changed from helixone 1.3 to 1.6 m2, p < 0.001) and haemodialysis modality (56.8% of patients changed from conventional haemodialysis to on-line haemodiafiltration, p < 0.001). We conclude that monitoring dialysis dose with Kt is a good clinical measure of adequacy, and using it as a quality indicator can be done in line with the more demanding quality standards.

[Importance of ultrapure dialysis liquid in response to the treatment of renal anaemia with darbepoetin in patients receiving haemodialysis]. / Importancia del líquido de diálisis ultrapuro en la respuesta al tratamiento de la anemia renal con darbepoetina en el paciente en hemodiálisis.

Chronic inflammatory diseases and infections are a major cause of hyporesponse to erythropoiesis-stimulating factors. We conducted this prospective study in 107 patients in haemodialysis with dialysis liquid that was potentially contaminated from a bacteriological perspective in order to test the hypothesis that ultrapure dialysis liquid can improve the response to treatment with darbepoetin and reduce inflammatory markers. These patients had to have been stable in the last 8 weeks in relation to haemoglobin level and the administered dose of darbepoetin. Two filters (one of hydrophilic nylon and another of polysulfone) were added to the water treatment process, the first one prior to distribution ring output and the second before the dialyser. The patients were evaluated for 12 months. The dosage of darbepoetin was varied to maintain haemoglobin levels ranging from 11 to 14 g/dl. We measured resistance to the erythropoiesis-stimulating factor, defined as the quotient between weekly dose of darbepoetin and haemoglobin levels, baseline and every two months, the baseline and monthly endotoxin count and reactive protein C at baseline and every 6 months. 94 patients completed the study. The resistance index fell significantly during follow-up (p<0.001) and was measurable from the second month on. Haemoglobin levels remained within the established margins with a 34% reduction in the weekly dose of darbepoetin at the end of the follow-up period. Both reactive protein C and the endotoxin count were significantly reduced (p<0.001) compared to baseline after 6 and 12 months. To conclude, the bacteriological purity of the dialysis liquid reduces inflammatory markers in patients receiving haemodialysis, improving the response to treatment with darbepoetin in renal anaemia.