Would prescribing target Kt dose adjusted for body surface area improve hemodialysis outcomes?

The use of Kt/V to prescribe and monitor hemodialysis adequacy remains the current standard, although it is increasingly questioned. Alternative proposals for dose prescription and monitoring have been advocated. In a noninterventional, prospective study reported in this issue, Maduell et al., utilizing online ionic dialysance, explore the association between outcome measures (mortality and hospitalization rates) and the extent to which delivered Kt dose achieved minimal target Kt doses calculated from individual estimates of body surface area.

A new technique for low-volume continuous sampling of spent dialysate: a validation study

The measure of hemodialysis (HD) adequacy recommended nowadays by most guidelines, Kt/V-urea, presents significant drawbacks. Direct dialysis quantification (DDQ) through total dialysate collection (TDC), considered the gold standard measure of HD adequacy, is cumbersome, which precludes its widespread use in clinical practice. The present study aims to validate a low-volume continuous sampling of spent dialysate (CSSD). Cross-sectional study carried out at a university hospital. Throughout 4-h hemodialysis sessions, urea removal was measured by three DDQ methods: TDC, CSSD, and fractional sampling of dialysate (FSD). The primary outcome was the comparison between the total mass of urea removed measured by TDC and the dialysate sampling techniques. The comparison between urea distribution volume (UDV) estimated by anthropometric method and through DDQ was a secondary outcome. The analysis was done through linear regression and Bland-Altman concordance method. Twenty HD sessions were studied. The mean amount of urea collected in TDC and calculated from the 40-mL sample of CSSD were 33.70 ± 11.70 g and 33.90 ± 11.70 g, respectively [r 0.96, p < 0.0001; bias - 0.2 (95% CI - 1.8 to 1.4); limits of agreement - 6.8 to 6.4]. The anthropometric measure, when compared with DDQ method, underestimated UDV in patients with smaller body size. This new simple, inexpensive, and small volume CSSD technique can provide accurate information about the total amount of solutes removed by hemodialysis.