Kt/V from PRU

Quantify hemodialysis adequacy


1.Percent Reduction of Urea?


Result 1 is calculated using the following formula:
Kt/V = (0.026 - PRU) - 0.460

Result 2 is calculated using the following formula:
Kt/V = (0.24 - PRU) - 0.276

Recall that:
Percent Reduction Urea (PRU) = (1  -  [postdialysis BUN  ÷  predialysis BUN]) X 100%

These equations are frequently used because of their simplicity, and though reasonably accurate, are generally felt to be inferior to the forumula used in our calculator entitled "Kt/V Daugirdas". Although using the PRU is useful as an epidemiologic tool, its utility in individual patients is more limited because of the considerable range of Kt/V that can be seen for any given PRU. Part of this variability is due to the fact that PRU does not take into account urea removal that occurs with ultrafiltration.


Daugirdas JT.

Rapid methods of estimating Kt/V: three formulas compared.

ASAIO Transactions 1990, 36 (3): M362-4

Lowrie EG, Lew NL.

The urea reduction ratio (URR). A simple method for evaluating hemodialysis treatment. Contemp Dial Nephrol 1992; 12:11.

The Kt/V from PRU calculator is created by QxMD.

Created by on 01/09/2015

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1. Percent Reduction of Urea?

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