The lacking equation that estimates the protein catabolic rate in patients on once-weekly haemodialysis.

Background: The normalized protein catabolic rate (PCRn) is one of the key indices derived from the urea kinetic model (UKM) in haemodialysis (HD) patients. Ideally, it should be assessed using the double pool UKM (KDOQI clinical practice guidelines, AIKD, 2015), as the web-based software Solute-Solver (SS) does (Daugirdas et al., AJKD, 2009).

What volume to choose to assess online Kt/V?

Introduction: Urea distribution volume (V) can be assessed in different ways, among them the anthropometric Watson Volume (V). However, many studies have shown that V does not coincide with V and that the latter can be more accurately estimated with other methods. The present multicentre study was designed to answer the question: what V to choose to assess online Kt/V?

Materials And Methods: Pre- and postdialysis blood urea nitrogen concentrations and the usual input data set for urea kinetic modelling were obtained for a single dialysis session in 201 Caucasian patients treated in 9 Italian dialysis units.