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Urea Reduction Ratio

Item Value
Available Stat? No
Test code URR
Test group Urea
Performed by Parnassus Chemistry
In House Availability Test available 24 hours per day 7 days per week
Method Enzymatic conductivity, kinetic (urease)
Container type Gold top or Light green top
Amount to Collect 1 mL blood Click here for Microdetermination info
Sample type Serum or plasma
Preferred volume 0.5 mL serum or plasma
Min. Volume 0.2 mL serum or plasma Click here for Microdetermination info
Units %
Normal range
Synonyms URR
Stability Room temperature 8 hours, refrigerated 2 days, frozen at -20C 1 week.
Turn around times 4 hours
Additional information Urea Reduction Ratio orders include the following parameters:

a. Post Dialysis BUN (mg/dL)

b. Urea Reduction Ratio: (Pre-dialysis BUN – Post-dialysis BUN) x 100 / Pre-dialysis BUN = %


c. Quick Kt/V (Jindal): [0.04 x (Pre-dialysis BUN – Post-dialysis BUN) – 1.2] / (Pre-dialysis BUN x 100)

Quick Kt/V correlates with full Kt/V within the range 0.6 to 1.8
CPT coding 84520
Last Updated 1/30/2013 12:22:50 PM
Entry Number 1170
Lab Procedure Link Click here for Procedure
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