The urea reduction ratio (URR) reflects the degree of urea removal associated with a hemodialysis session.
Patient selection: patient undergoing hemodialysis
Parameters:
(1) predialysis serum BUN (or urea)
(2) postdialysis serum BUN (or urea)
urea reduction ratio =
= 1 - ((postdialysis BUN) / (predialysis BUN))
Interpretation:
• minimum URR: 0
• maximum URR: 1
• A URR less than 0.65 may indicate inadequate dialysis.
