Determinants of Discard of Kidneys From Expanded Criteria Donors Undergoing Donation After Circulatory Death.

Abstract

Background The use of combined expanded criteria donor (ECD) and donation after circulatory death (DCD) kidneys is a potential strategy to expand the donor pool. Prior research showed that DCD kidneys have a slightly increased risk of graft failure vs non-DCD kidneys, but the relative risk was not significantly greater amongst ECD vs non-ECD kidneys. The Kidney Donor Risk Index (KDRI) in the ECD/DCD group was similar to those in the ECD/non-DCD group, suggesting careful selection of ECD/DCD kidneys. Methods A cross sectional study of ECD/DCD kidneys recovered from adult donors from 2000 to 2011 was conducted using the SRTR. Donor characteristics and KDRI scores of discarded and transplanted ECD/DCD kidneys were assessed and multivariable logistic regression models were used to determine the odds of discard based on donor factors. Results There were 894 ECD/DCD kidneys included in the study, of which 34.2% were discarded. The median KDRI in transplanted vs discarded organs was 1.78 (IQR 0.69) vs 1.98 (IQR 0.89), respectively (P < 0.001) although the distribution of KDRI scores between discarded and transplanted kidneys showed considerable overlap.Figure: No Caption available.In logistic regression models, the odds of discard were higher if ECD/DCD kidneys were recovered from diabetic donors (OR 1.68 [95% CI 1.16, 2.45] P = 0.007) and hepatitis B or C positive donors (OR 2.73 [95% CI 1.37, 5.43] and OR 4.16 [95% CI 1.56, 11.08], P = 0.004 for both). Pulsatile machine perfusion was associated with decreased odds of discard (OR 0.32 [95% CI 0.22, 0.44], P < 0.001). Other factors such as age, race, death by CVA, hypertension and weight were not associated with increased odds of discard. Conclusions This study demonstrates a high discard rate of ECD/DCD kidneys, some of which may be acceptable for transplantation given their favorable donor characteristics and KDRI scores.