Pulsatile Perfusion Characteristics of En Bloc Kidneys Transplanted from Small Pediatric Donors May Predict Early Allograft Failure

Abstract

INTRODUCTION: Although hypothermic pulsatile perfusion (PP) is commonly used to evaluate the viability of adult donor kidneys before transplantation, little is known about its application to kidneys from small pediatric deceased donors. In this study, we analyze the PP characteristics of pediatric en bloc (PEB) kidneys from this underused source and develop predictive models for early allograft failure (EAF). METHODS: We reviewed PP characteristics of PEB kidneys from donors weighing <20 kg transplanted at our institution between 2010 and 2020. Analysis of variance was performed on PP characteristics by donor weight quartiles, and chi-square test was applied to identify thresholds for EAF within 90 days of transplantation. Logistic regression models to predict EAF were also developed. RESULTS: During the study period, 265 patients (98% adult) underwent transplantation using PEB kidneys from donors with a median (range) weight of 6.5 kg (1.9 to 18.9 kg). We found that as donor weight decreases, terminal resistance increases (Figure). Within donor weight quartiles, higher resistance was associated with EAF, though not statistically significant throughout. In the 1 to 5 kg and 5 to 10 kg quartiles, resistance ≥1.1 and 0.8 mmHg/mL/min, respectively, was significantly associated with EAF (p = 0.038, p = 0.014, respectively). A logistic regression model to predict EAF using resistance/donor weight had moderate discrimination with a c-statistic = 0.657.FigureCONCLUSION: These findings enhance our understanding of PP characteristics of small PEB kidneys and demonstrate that changes in resistance occur as a function of donor weight. Elevated resistance may be an important consideration in estimating the risk of EAF.