Online Kt/V (Urea) monitoring in maintenance hemodialysis patients, single center experience.

Introduction: Dialysis adequacy is an important factor affecting overall morbidity and mortality in patients on maintenance hemodialysis, The Urea reduction Rate (URR) measures the change between pre-dialysis and post-dialysis serum urea levels. Single pool Urea clearance index (Kt/V) was developed to include both the volume of distribution of urea and the time of effective dialysis session in the equation of determining dialysis adequacy; recently online volume monitoring and hence online Kt/V (urea) were incorporated in the dialysis machines to facilitate measurement of dialysis adequacy. Aim of The Work: evaluate the relation between On-line Kt/VUrea and the conventional adequacy measurement method Urea Reduction ratio (URR). Methods: 208 patients on maintenance Hemodialysis at Dubai Hospital –Dubai Heath Authority, for at least 3 months and followed up for 4 months were included. Results and Discussion: 108 Patients were male (52%) and 100 females (48%), age (Mean±SD) 59±18.6 years old, and Duration on dialysis (Mean±SD) 51.2±21 months. We found a statistically significant correlation between the online Kt/V and the measured one. R-square 0.209 and P-value 0.002, which was independent of the other covariates included in the model. ROC analysis showed the online value of online Kt/V in comparison to the standard measured URR at different URR cut-off values, at URR > 60%, the overall model accuracy 83% with area under the curve AUC (95%CI) 0.873(0.805-0.942) P-value < 0.001. With higher URR > 70%, the overall model accuracy improved to 87.4% with area under the curve AUC (95%CI) 0.913(0.875-0.951) P-value < 0.001. Conclusion: Our results confirm the hypothesis that the online Kt/V Urea function incorporated in many recent dialysis machines is a sensitive indicator of dialysis adequacy delivered during hemodialysis sessions.