Barriers and Opportunities to Increase Utilization of Donor Kidneys After Death Determined by Circulatory Criteria Among Children and Adults: A Narrative Review

Purpose of Review: Kidney transplantation is associated with survival benefit compared to dialysis. Yet, there is an unmet need for access to kidney transplantation within Canada and globally. Donation after death determined by circulatory criteria (DCC) has expanded access to kidney transplantation among the adult and pediatric population. However, there are concerns inherent to DCC kidneys, including warm ischemia time and ischemia-reperfusion injury (IRI). This narrative review aims to summarize relevant literature in this context, discuss potential opportunities to expand the use of DCC kidneys, and highlight knowledge gaps for further study. Sources of Information: PubMed (Medline), the Canadian Institute for Health Information, and regulatory bodies for organ donation and transplantation. Methods: A focused review and critical appraisal of existing literature on the mechanisms of kidney IRI, consideration of sex in experimental studies relevant to DCC kidney transplantation, ex vivo perfusion strategies, and pediatric kidney transplant considerations. Key Findings: DCC kidneys confer a higher risk of delayed graft function (DGF) due to prolonged warm ischemic time. However, long-term graft survival is generally comparable to that of kidneys from donors with death determined by neurologic criteria (DNC). Key barriers to expansion include the paucity of sex-balanced experimental studies on DCC graft preservation and outcomes and existing protocols for DCC donor selection, including thresholds for warm ischemia time. Ex vivo strategies including non-oxygenated and oxygenated hypothermic machine perfusion and normothermic ex vivo kidney perfusion are promising research areas. Improving DCC protocols to reduce kidney IRI has the potential to further expand access to DCC transplantation, including to the pediatric population. Limitations: This narrative review only included articles written in English. Study quality was not formally assessed. Discussion points were influenced by the author's areas of expertise.