Kt/V is used to measure how effective a haemodialysis treatment is. It is based on tests of blood urea, by measuring the levels before and after treatment, to show how much has been removed. URR is a simpler test of haemodialysis effectiveness: some units use URR, some use Kt/V, some use both.

In the UK the agreed target Kt/V is a minimum of 1.2. This applies to someone receiving dialysis three times each week. A slightly lower value may be OK if you still have some function from your own kidneys, unless this has also been taken into account in calculating Kt/V.

Lower values are associated with poorer survival on dialysis. Of course other things affect how long you will live too. A single low value is nothing to get too worried about but it is best if all values are good. Even with a very high Kt/V, it may not be sensible to reduce the length of each dialysis treatment, as duration of dialysis may be important to keep your fluid balance just right.

Causes of low Kt/V include

How to improve Kt/V and/or dialysis dose - possibilities include

More information about URR and Kt/V from the NIDDK (USA) - detailed and thorough

More information about URR and Kt/V from ikidney.com - a bit easier

This page created 20th July 2005, last modified Feb 16, 2015, on the PatientView website