Prolonged warm ischemia time is associated with graft failure and mortality after kidney transplantation

Abstract

Warm ischemia time is a potentially modifiable insult to transplanted kidneys, but little is known about its effect on long-term outcomes. Here we conducted a study of United States kidney transplant recipients (years 2000-2013) to determine the association between warm ischemia time (the time from organ removal from cold storage to reperfusion with warm blood) and death/graft failure. Times under 10 minutes were potentially attributed to coding error. Therefore, the 10-to-under-20-minute interval was chosen as the reference group. The primary outcome was mortality and graft failure (return to chronic dialysis or preemptive retransplantation) adjusted for recipient, donor, immunologic, and surgical factors. The study included 131,677 patients with 35,901 events. Relative to the reference patients, times of 10 to under 20, 20 to under 30, 30 to under 40, 40 to under 50, 50 to under 60, and 60 and more minutes were associated with hazard ratios of 1.07 (95% confidence interval, 0.99-1.15), 1.13 (1.06-1.22), 1.17 (1.09-1.26), 1.20 (1.12-1.30), and 1.23 (1.15-1.33) for the composite event, respectively. Association between prolonged warm ischemia time and death/graft failure persisted after stratification by donor type (living vs. deceased donor) and delayed graft function status. Thus, warm ischemia time is associated with adverse long-term patient and graft survival after kidney transplantation. Identifying strategies to reduce warm ischemia time is an important consideration for future study.

New Factors Predicting Delayed Graft Function: a Multi-Center Cohort Study of Kidney Donation After Brain Death Followed by Circulatory Death

“…Consistent with other studies, our findings suggest that prolonged WIT was particularly detrimental to kidneys from DBCD donation, and was associated with a higher risk of DGF [29,30]. WIT of > 18 min increased DGF risk 2.42-fold compared with < 18 min.…”

Chronic kidney disease, kidney transplantation and oxidative stress: a new look to successful kidney transplantation

“…It causes an oxidative burst that triggers inflammation and tubular cell injury. In a recent study, Tennankore et al [23] showed a correlation between prolonged warm ischemia and mortality and graft failure. Evidences suggests that NADPH oxidase is activated during RIR injury and may play a potential role in the pathogenesis of progressive renal damage in this setting.…”

The influence of warm ischemia elimination on kidney injury during transplantation – clinical and molecular study

“…in a study on 131,677 kidney transplant recipients found that WIT longer than 30 min was associated with a statistically higher adjusted relative hazard for the composite event of death or graft failure. In the case of WIT > 60 min, a 23% increase in the adjusted relative hazard for death or graft failure was observed4. Similarly, Heylen et al .…”

“…Warm ischemia time (WIT) is a period which begins at the time of removal of the procured organ from storage ice and ends with the initiation of graft reperfusion, depending on the anastomosis time of renal vessels. Prolongation of WIT is not only detrimental for immediate renal allograft function but also influences long-term results34. Prolonged WIT was also associated with longer hospitalization after kidney transplantation5 and impaired long-term graft survival after living donation6 as well as deceased donor7 kidney transplantation.…”