The impact of cold ischemia time on outcomes of deceased donor kidney transplantation: does every hour count?

H. Peters-Sengers, J.H.E. Houtzager, M.M. Idu, M.B.A. Heemskerk, L.W.E. van Heurn, J.J. Homan van der Heide, S.P. Berger, J. Kers, T.M. van Gulik, F.J. Bemelman

Thursday 15 march 2018

12:15 - 12:25h at Willem Burger Zaal

Categories: Clinical, Session (parallel)

Parallel session: Parallel session 3: Clinical

Aim

Cold Ischemic Time (CIT) is a well-known risk factor among the renal transplant community, however its precise limits to define high-risk donor kidneys for transplantation are not yet clear. Evidence suggests that kidneys from circulatory-death donors are particularly affected by cold ischaemic injury. We aimed to compare impact of cold ischaemic time in circulatory-death versus brain-death donor kidneys on graft failure and mortality, and relate these limits to donor age.

Methods

We used the prospective Dutch Organ Transplantation Registry to include 2153 adult recipients of first brain-death (n=1266) and circulatory-death (n=887) donor kidneys after static cold storage, transplanted from 2005 to 2012. Final follow-up date was May 1, 2015. CIT was non-linearly modelled with splines. Analyses were adjusted for 21 confounders, considered by literature search and clinical experience. Associations and interactions between CIT, donor type, donor age and five-year (death-censored) graft survival, and mortality were evaluated.

Results

Median cold ischaemia time was 16.2 hours (IQR 12.8-20.0), ranging from 3.4 to 44.7 hours for brain-death, and 4.7 to 46.6 hours for circulatory-death donor kidneys. At 22 hours of cold ischaemia time or more, five-year graft failure risk was significantly higher for kidneys donated after circulatory-death versus brain-death (adjusted HR 1.45, 95%CI 1.01-2.49, p=0.043). This risk was significantly higher at 19 hours of cold ischaemia time if kidneys were from 60-year-old circulatory-death donors compared to brain-death donors of same age (adjusted HR 1.33, 95%CI 1.00-1.78, p=0.045). The additional insult of increased cold ischaemia in kidneys from circulatory-death donors was also found for death-censored graft failure, but did not show significant differences on the outcome of mortality. Within the Eurotransplant Senior Program, where donors aged ≥65 years are allocated to recipients aged ≥65 years, also an increased five-year risk of graft failure was observed if donors were from DCD.

Conclusions

Circulatory-death as compared to brain-death kidneys are less resilient to ischemia-mediated damaged with a significant higher risk for graft failure after 22 hours of CIT. Our data can help to optimize the scheduling of the surgery, and future studies can implicate whether there may be different limits for CIT using machine perfusion.