For a marginal DCD kidney on perfusion, are you seeing a real reconditioning effect, or is the perfusion run mostly functioning as a viability test that tells you whether to use the organ at all?

This is not a straightforward question and therefore doesn't have a straightforward answer. The first part is that the pump numbers can be helpful to determine if it is viable, but really only if the numbers are not improving and show high resistance and poor flow. These kidneys will not do as well and have increased risk of DGF and issues. So this helps me to turn down a marginal kidney with bad parameters, particularly if there is no improvement. But good pump numbers don't ensure a good kidne...

I think the answer to this question is both reconditioning and predictive of viability. It has been shown in the literature that hypothermic machine perfusion of renal allografts improves outcomes, especially in DCD kidneys. The mechanism of this is not clearly understood, but theoretically it is likely due to the flushing of inflammatory mediators, antigens, and antigen-presenting cells over the time of perfusion.

As a viability test, the best predictor of possible downstream pathology is the r...

The question is difficult to answer. Type of perfusion? Donor age? Terminal creatinine? Length of functional warm ischemia prior to death, etc. There is emerging literature that the use of normothermic regional perfusion (ECMO) can reduce the rate of kidney transplant DGF in DCD donors. Usually the liver is also recovered. There are a number of small case series that demonstrate some viability advantage for normothermic ex vivo perfusion.

However, in an RCT using a proprietary ex vivo normothermi...