Potential of Donation After Unexpected Circulatory Death Programs Defined by Their Demographic Characteristics.

BACKGROUND: Donation after unexpected circulatory death (uDCD) donors are often suggested to increase the number of donor organs. In 2014, a uDCD protocol was implemented in three transplant centers in the Netherlands which unfortunately did not result in additional transplantations. This study was initiated to identify demographic factors influencing the potential success of uDCD programs. METHODS: Dutch resuscitation databases covering various demographic regions were analyzed for potential donors. The databases were compared with the uDCD implementation project and successful uDCD programs in Spain, France, and Russia. RESULTS: The resuscitation databases showed that 61% of all resuscitated patients were transferred to an emergency department. Age selection reduced this uDCD potential to 46% with only patients aged 18-65 years deemed eligible. Of these patients, 27% died in the emergency department. The urban region of Amsterdam showed the largest potential in absolute numbers (52 patients/y). Comparison with the uDCD implementation project showed large similarities in the percentage of potential donors; however, in absolute numbers, it showed a much smaller potential. Calculation of the potential per million persons and the extrapolation of the potential based on the international experience revealed the largest potential in urban regions. CONCLUSIONS: Implementation of a uDCD program should not only be based on the number of potential donors calculated from resuscitation databases. They show promising potential uDCD percentages for large rural regions and small urban regions; however, actual numbers per hospital are low, leading to insufficient exposure rates. It is, therefore, recommendable to limit uDCD programs to large urban regions.

Hypothermic Machine Perfusion as a National Standard Preservation Method for Deceased Donor Kidneys.

BACKGROUND: Recently, continuous nonoxygenated hypothermic machine perfusion (HMP) has been implemented as standard preservation method for deceased donor kidneys in the Netherlands. This study was designed to assess the effect of the implementation of HMP on early outcomes after transplantation. METHODS: Kidneys donated in the Netherlands in 2016 and 2017 were intended to be preserved by HMP. A historical cohort (2010-2014) preserved by static cold storage was chosen as the control group. Primary outcome was delayed graft function (DGF). Additional analyses were performed on safety, graft function, and survival up until 2 y after transplantation. RESULTS: Data were collected on 2493 kidneys. Analyses showed significantly more donation after circulatory death, preemptive transplantation, and retransplants in the project cohort. Of the 681 kidneys that were transplanted during the project, 81% were preserved by HMP. No kidneys were discarded due to HMP-related complications. DGF occurred in 38.2% of the project cohort versus 43.7% of the historical cohort (P < 0.001), with a significantly shorter duration within the project cohort (7 versus 9 d, P = 0.003). Multivariate regression analysis showed an odds ratio of 0.69 (95% confidence interval, 0.553-0.855) for the risk of DGF when using HMP compared with cold storage (P = 0.001). There was no significant difference in kidney function, graft survival, and recipient survival up until 2 y posttransplantation. CONCLUSIONS: This study showed that HMP as a standard preservation method for deceased donor kidneys is safe and feasible. HMP was associated with a significant reduction of DGF.

Proteomic analysis of machine perfusion solution from brain dead donor kidneys reveals that elevated complement, cytoskeleton and lipid metabolism proteins are associated with 1-year outcome.

Assessment of donor kidney quality is based on clinical scores or requires biopsies for histological assessment. Noninvasive strategies to identify and predict graft outcome at an early stage are, therefore, needed. We evaluated the perfusate of donation after brain death (DBD) kidneys during nonoxygenated hypothermic machine perfusion (HMP). In particular, we compared perfusate protein profiles of good outcome (GO) and suboptimal outcome (SO) 1-year post-transplantation. Samples taken 15 min after the start HMP (T1) and before the termination of HMP (T2) were analysed using quantitative liquid chromatography-tandem mass spectrometry (LC-MS/MS). Hierarchical clustering of the 100 most abundant proteins showed discrimination between grafts with a GO and SO at T1. Elevated levels of proteins involved in classical complement cascades at both T1 and T2 and a reduced abundance of lipid metabolism at T1 and of cytoskeletal proteins at T2 in GO versus SO was observed. ATP-citrate synthase and fatty acid-binding protein 5 (T1) and immunoglobulin heavy variable 2-26 and desmoplakin (T2) showed 91% and 86% predictive values, respectively, for transplant outcome. Taken together, DBD kidney HMP perfusate profiles can distinguish between outcome 1-year post-transplantation. Furthermore, it provides insights into mechanisms that could play a role in post-transplant outcomes.

Oxygenated End-Hypothermic Machine Perfusion in Expanded Criteria Donor Kidney Transplant: A Randomized Clinical Trial.

Importance: Continuous hypothermic machine perfusion during organ preservation has a beneficial effect on graft function and survival in kidney transplant when compared with static cold storage (SCS). Objective: To compare the effect of short-term oxygenated hypothermic machine perfusion preservation (end-HMPo2) after SCS vs SCS alone on 1-year graft survival in expanded criteria donor kidneys from donors who are brain dead. Design, Setting, and Participants: In a prospective, randomized, multicenter trial, kidneys from expanded criteria donors were randomized to either SCS alone or SCS followed by end-HMPo2 prior to implantation with a minimum machine perfusion time of 120 minutes. Kidneys were randomized between January 2015 and May 2018, and analysis began May 2019. Analysis was intention to treat. Interventions: On randomization and before implantation, deceased donor kidneys were either kept on SCS or placed on HMPo2. Main Outcome and Measures: Primary end point was 1-year graft survival, with delayed graft function, primary nonfunction, acute rejection, estimated glomerular filtration rate, and patient survival as secondary end points. Results: Centers in 5 European countries randomized 305 kidneys (median [range] donor age, 64 [50-84] years), of which 262 kidneys (127 [48.5%] in the end-HMPo2 group vs 135 [51.5%] in the SCS group) were successfully transplanted. Median (range) cold ischemia time was 13.2 (5.1-28.7) hours in the end-HMPo2 group and 12.9 (4-29.2) hours in the SCS group; median (range) duration in the end-HMPo2 group was 4.7 (0.8-17.1) hours. One-year graft survival was 92.1% (n = 117) in the end-HMPo2 group vs 93.3% (n = 126) in the SCS group (95% CI, -7.5 to 5.1; P = .71). The secondary end point analysis showed no significant between-group differences for delayed graft function, primary nonfunction, estimated glomerular filtration rate, and acute rejection. Conclusions and Relevance: Reconditioning of expanded criteria donor kidneys from donors who are brain dead using end-HMPo2 after SCS does not improve graft survival or function compared with SCS alone. This study is underpowered owing to the high overall graft survival rate, limiting interpretation. Trial Registration: isrctn.org Identifier: ISRCTN63852508.

Oxygenated versus standard cold perfusion preservation in kidney transplantation (COMPARE): a randomised, double-blind, paired, phase 3 trial.

BACKGROUND: Deceased donor kidneys are preserved in cold hypoxic conditions. Providing oxygen during preservation might improve post-transplant outcomes, particularly for kidneys subjected to greater degrees of preservation injury. This study aimed to investigate whether supplemental oxygen during hypothermic machine perfusion (HMP) could improve the outcome of kidneys donated after circulatory death. METHODS: This randomised, double-blind, paired, phase 3 trial was done in 19 European transplant centres. Kidney pairs from donors aged 50 years or older, donated after circulatory death, were eligible if both kidneys were transplanted into two different recipients. One kidney from each donor was randomly assigned using permuted blocks to oxygenated hypothermic machine perfusion (HMPO2), the other to HMP without oxygenation. Perfusion was maintained from organ retrieval to implantation. The primary outcome was 12-month estimated glomerular filtration rate (eGFR) using the Chronic Kidney Disease Epidemiology Collaboration equation in pairs of donated kidneys in which both transplanted kidneys were functioning at the end of follow-up. Safety outcomes were reported for all transplanted kidneys. Intention-to-treat analyses were done. This trial is registered with the ISRCTN Registry, ISRCTN32967929, and is now closed. FINDINGS: Between March 15, 2015, and April 11, 2017, 197 kidney pairs were randomised with 106 pairs transplanted into eligible recipients. 23 kidney pairs were excluded from the primary analysis because of kidney failure or patient death. Mean eGFR at 12 months was 50·5 mL/min per 1·73 m2 (SD 19·3) in the HMPO2 group versus 46·7 mL/min per 1·73m2 (17·1) in HMP (mean difference 3·7 mL/min per 1·73m2, 95% CI -1·0 to 8·4; p=0·12). Fewer severe complications (Clavien-Dindo grade IIIb or more) were reported in the HMPO2 group (46 of 417, 11%, 95% CI 8% to 14%) than in the HMP group (76 of 474, 16%, 13% to 20%; p=0·032). Graft failure was lower with HMPO2 (three [3%] of 106) compared with HMP (11 [10%] of 106; hazard ratio 0·27, 95% CI 0·07 to 0·95; p=0·028). INTERPRETATION: HMPO2 of kidneys donated after circulatory death is safe and reduces post-transplant complications (grade IIIb or more). The 12-month difference in eGFR between the HMPO2 and HMP groups was not significant when both kidneys from the same donor were still functioning 1-year post-transplant, but potential beneficial effects of HMPO2 were suggested by analysis of secondary outcomes. FUNDING: European Commission 7th Framework Programme.

Factors That Complicated the Implementation of a Program of Donation After Unexpected Circulatory Death of Lungs and Kidneys. Lessons Learned From a Regional Trial in the Netherlands.

BACKGROUND: Organ shortage remains a problem in transplantation. An expansion of the donor pool could be the introduction of unexpected donation after circulatory death (uDCD) donors. The goal of this study was to increase the number of transplantable kidneys and lungs by implementing a uDCD protocol. METHODS: A comprehensive protocol for uDCD donation was developed and implemented in the emergency departments (EDs) of 3 transplant centers. All out-of-hospital cardiac arrest (OHCA) patients were screened for uDCD donation. Inclusion criteria were declaration of death in the ED, age (<50 y for kidneys, <65 y for lungs), witnessed arrest, and basic and advanced life support started within 10 and 20 min, respectively. RESULTS: A total of 553 OHCA patients were reported during the project, of which 248 patients survived (44.8%). A total of 87 potential lung and 42 potential kidneys donors were identified. A broad spectrum of reasons resulted in termination of all uDCD procedures. Inclusion and organ-specific exclusion criteria were the most common reason for not proceeding followed by consent. None of the potential donors could be converted into an actual donor. CONCLUSION: Although uDCD potential was shown by successful recognition of potential donors in the ED, we were not able to transplant any organs during the study period. The Dutch Emergency medical service guidelines to stop futile OHCA in the prehospital setting and the strict use of inclusion and exclusion criteria like age and witnessed arrest hampered the utilization. A prehospital uDCD protocol to bring all OHCA patients who are potential uDCD candidates to an ED would be helpful in creating a successful uDCD program.

Effects of Oxygen During Long-term Hypothermic Machine Perfusion in a Porcine Model of Kidney Donation After Circulatory Death.

BACKGROUND: Hypothermic machine perfusion (HMP) has become standard care in many center's to preserve kidneys donated after circulatory death (DCD). Despite a significant reduction in metabolism at low temperatures, the remaining cellular activity requires oxygen. Because of the role and safety of oxygen during HMP has not been fully clarified, its supply during HMP is not standard yet. This study investigates the effect of administering oxygen during HMP on renal function in a porcine DCD model. METHODS: After 30 minutes of warm ischemia, porcine slaughterhouse kidneys were preserved for 24 hours by means of cold storage (CS), or HMP with Belzer Machine Perfusion Solution supplemented with no oxygen, 21% or 100% oxygen. Next, kidneys were reperfused for 4 hours in a normothermic machine perfusion setup. RESULTS: HMP resulted in significantly better kidney function during normothermic machine perfusion. Thiobarbituric acid-reactive substances, markers of oxidative stress, were significantly lower in HMP preserved kidneys. HMP preserved kidneys showed significantly lower aspartate aminotransferase and lactate dehydrogenase levels compared with kidneys preserved by CS. No differences were found between the HMP groups subjected to different oxygen concentrations. Adenosine triphosphate levels significantly improved during HMP when active oxygenation was applied. CONCLUSIONS: This study showed that preservation of DCD kidneys with HMP is superior to CS. Although the addition of oxygen to HMP did not result in significantly improved renal function, beneficial effects were found in terms of reduced oxidative stress and energy status. Oxygen addition proofed to be safe and did not show detrimental effects.

Novel preservation methods to increase the quality of older kidneys.

PURPOSE OF REVIEW: The purpose of this review was to summarize the novel developments in preservation of older kidneys. RECENT FINDINGS: The importance of older donors as a source of renal grafts is increasing, with a concomitant increase of posttransplant failure. Preservation of kidneys retrieved from older donors through hypothermic machine perfusion reduces delayed graft function rate and increases long-term graft survival. Assessment of renal function and selection through biomarkers or perfusion criteria to predict posttransplant function are limited. Normothermic perfusion offers the benefit of reperfusion under ideal circumstances, thereby reducing ischemic injury while having the opportunity to test graft viability and preselect kidneys on graft-specific characteristics. Both preservation methods enable active treatment of the isolated graft prior to transplantation, with stem cells or pharmaceuticals. SUMMARY: Older kidneys are more prone to acute kidney injury during ischemic periods combined with an impaired ability to fully recover after transplantation. Novel preservation and resuscitation methods provide the opportunity to select transplantable kidneys better founded or even repair re-existing damage reducing the risk of impaired graft function and improving survival.