A comparison between urea reduction ratio and urea kinetic model in assessing hemodialysis adequacy in end stage renal disease

In recent years the burden of chronic kidney disease has increased worldwide. End Stage Renal Disease (ESRD) needs Hemodialysis as a common renal replacement therapy to reduce its morbidity and mortality. Hemodialysis adequacy must be maintained for effective treatment and is measured either by Urea Kinetic Model (Kt/V), Urea Reduction Ratio (URR), natural log Kt/V or Daugirdas 2^nd generation formula. Though Kt/V is accurate, URR is commonly used in clinical practice because of its simplicity and clear concept.

To estimate and compare URR with single pool Kt/V in assessing hemodialysis adequacy.

An experimental prospective study consisting of 100 ESRD patients of either sex between 18–70 years, who were on hemodialysis maintenance. Blood urea was estimated by GLDH-urease method and serum creatinine by Jaffe's method. Values were substituted in URR and Kt/V formula.

There was a significant difference in serum Urea levels after dialysis treatment (P< 0.05). The values of URR and kinetic model of urea (Kt/V) were near to adequacy guidelines set by National Kidney Foundation: KDOQI. URR showed positive correlation with Kt/V. Since the URR and Kt/V are closely related, their predictive power in terms of patient outcome is similar. However, use of Kt/V and urea modelling allows for comparing expected with predicted dialysis dose that can be used to analyse dialysis treatment and dialyzer clearance.