Transplantation of kidneys from uncontrolled donation after circulatory determination of death: comparison with brain death donors with or without extended criteria and impact of normothermic regional perfusion

Kidney Transplantation Outcomes From Uncontrolled Donation After Circulatory Death: A Systematic Review and Meta-analysis

BACKGROUND

Uncontrolled donation after circulatory death (uDCD) is a potential additional source of donor kidneys. This study reviewed uDCD kidney transplant outcomes to determine if these are comparable to controlled donation after circulatory death (cDCD).

METHODS

MEDLINE, Cochrane, and Embase databases were searched. Data on demographic information and transplant outcomes were extracted from included studies. Meta-analyses were performed, and risk ratios (RR) were estimated to compare transplant outcomes from uDCD to cDCD.

RESULTS

Nine cohort studies were included, from 2178 uDCD kidney transplants. There was a moderate degree of bias, as 4 studies did not account for potential confounding factors. The median incidence of primary nonfunction in uDCD was 12.3% versus 5.7% for cDCD (RR, 1.85; 95% confidence intervals, 1.06-3.23; P  = 0.03, I 2  = 75). The median rate of delayed graft function was 65.1% for uDCD and 52.0% for cDCD. The median 1-y graft survival for uDCD was 82.7% compared with 87.5% for cDCD (RR, 1.43; 95% confidence intervals, 1.02-2.01; P  = 0.04; I 2  = 71%). The median 5-y graft survival for uDCD and cDCD was 70% each. Notably, the use of normothermic regional perfusion improved primary nonfunction rates in uDCD grafts.

CONCLUSIONS

Although uDCD outcomes may be inferior in the short-term, the long-term outcomes are comparable to cDCD.

Perfusion Techniques in Kidney Allograft Preservation to Reduce Ischemic Reperfusion Injury: A Systematic Review and Meta-Analysis

The limited supply and rising demand for kidney transplantation has led to the use of allografts more susceptible to ischemic reperfusion injury (IRI) and oxidative stress to expand the donor pool. Organ preservation and procurement techniques, such as machine perfusion (MP) and normothermic regional perfusion (NRP), have been developed to preserve allograft function, though their long-term outcomes have been more challenging to investigate. We performed a systematic review and meta-analysis to examine the benefits of MP and NRP compared to traditional preservation techniques. PubMed (MEDLINE), Embase, Cochrane, and Scopus databases were queried, and of 13,794 articles identified, 54 manuscripts were included (n = 41 MP; n = 13 NRP). MP decreased the rates of 12-month graft failure (OR 0.67; 95%CI 0.55, 0.80) and other perioperative outcomes such as delayed graft function (OR 0.65; 95%CI 0.54, 0.79), primary nonfunction (OR 0.63; 95%CI 0.44, 0.90), and hospital length of stay (15.5 days vs. 18.4 days) compared to static cold storage. NRP reduced the rates of acute rejection (OR 0.48; 95%CI 0.35, 0.67) compared to in situ perfusion. Overall, MP and NRP are effective techniques to mitigate IRI and play an important role in safely expanding the donor pool to satisfy the increasing demands of kidney transplantation.

Predicting Kidney Transplantation Outcomes from Donor and Recipient Characteristics at Time Zero: Development of a Mobile Application for Nephrologists

(1) Background: We report on the development of a predictive tool that can estimate kidney transplant survival at time zero. (2) Methods: This was an observational, retrospective study including 5078 transplants. Death-censored graft and patient survivals were calculated. (3) Results: Graft loss was associated with donor age (hazard ratio [HR], 1.021, 95% confidence interval [CI] 1.018-1.024, p < 0.001), uncontrolled donation after circulatory death (DCD) (HR 1.576, 95% CI 1.241-2.047, p < 0.001) and controlled DCD (HR 1.567, 95% CI 1.372-1.812, p < 0.001), panel reactive antibody percentage (HR 1.009, 95% CI 1.007-1.011, p < 0.001), and previous transplants (HR 1.494, 95% CI 1.367-1.634, p < 0.001). Patient survival was associated with recipient age (> 60 years, HR 5.507, 95% CI 4.524-6.704, p < 0.001 vs. < 40 years), donor age (HR 1.019, 95% CI 1.016-1.023, p < 0.001), dialysis vintage (HR 1.0000263, 95% CI 1.000225-1.000301, p < 0.01), and male sex (HR 1.229, 95% CI 1.135-1.332, p < 0.001). The C-statistics for graft and patient survival were 0.666 (95% CI: 0.646, 0.686) and 0.726 (95% CI: 0.710-0.742), respectively. (4) Conclusions: We developed a mobile app to estimate survival at time zero, which can guide decisions for organ allocation.

Organ Donation After Out-of-Hospital Cardiac Arrest: A Scientific Statement From the International Liaison Committee on Resuscitation

AIM OF THE REVIEW

Improving rates of organ donation among patients with out-of-hospital cardiac arrest who do not survive is an opportunity to save countless lives. The objectives of this scientific statement were to do the following: define the opportunity for organ donation among patients with out-of-hospital cardiac arrest; identify challenges and opportunities associated with organ donation by patients with cardiac arrest; identify strategies, including a generic protocol for organ donation after cardiac arrest, to increase the rate and consistency of organ donation from this population; and provide rationale for including organ donation as a key clinical outcome for all future cardiac arrest clinical trials and registries.

METHODS

The scope of this International Liaison Committee on Resuscitation scientific statement was approved by the International Liaison Committee on Resuscitation board and the American Heart Association, posted on ILCOR.org for public comment, and then assigned by section to primary and secondary authors. A unique literature search was completed and updated for each section.

RESULTS

There are a number of defining pathways for patients with out-of-hospital cardiac arrest to become organ donors; however, modifications in the Maastricht classification system need to be made to correctly identify these donors and to report outcomes with consistency. Suggested modifications to the minimum data set for reporting cardiac arrests will increase reporting of organ donation as an important resuscitation outcome. There are a number of challenges with implementing uncontrolled donation after cardiac death protocols, and the greatest impediment is the lack of legislation in most countries to mandate organ donation as the default option. Extracorporeal cardiopulmonary resuscitation has the potential to increase organ donation rates, but more research is needed to derive neuroprognostication rules to guide clinical decision-making about when to stop extracorporeal cardiopulmonary resuscitation and to evaluate cost-effectiveness.

CONCLUSIONS

All health systems should develop, implement, and evaluate protocols designed to optimize organ donation opportunities for patients who have an out-of-hospital cardiac arrest and failed attempts at resuscitation.

Organ Donation After Out-of-Hospital Cardiac Arrest: A Scientific Statement From the International Liaison Committee on Resuscitation

AIM OF THE REVIEW

Improving rates of organ donation among patients with out-of-hospital cardiac arrest who do not survive is an opportunity to save countless lives. The objectives of this scientific statement were to do the following: define the opportunity for organ donation among patients with out-of-hospital cardiac arrest; identify challenges and opportunities associated with organ donation by patients with cardiac arrest; identify strategies, including a generic protocol for organ donation after cardiac arrest, to increase the rate and consistency of organ donation from this population; and provide rationale for including organ donation as a key clinical outcome for all future cardiac arrest clinical trials and registries.

METHODS

The scope of this International Liaison Committee on Resuscitation scientific statement was approved by the International Liaison Committee on Resuscitation board and the American Heart Association, posted on ILCOR.org for public comment, and then assigned by section to primary and secondary authors. A unique literature search was completed and updated for each section.

RESULTS

There are a number of defining pathways for patients with out-of-hospital cardiac arrest to become organ donors; however, modifications in the Maastricht classification system need to be made to correctly identify these donors and to report outcomes with consistency. Suggested modifications to the minimum data set for reporting cardiac arrests will increase reporting of organ donation as an important resuscitation outcome. There are a number of challenges with implementing uncontrolled donation after cardiac death protocols, and the greatest impediment is the lack of legislation in most countries to mandate organ donation as the default option. Extracorporeal cardiopulmonary resuscitation has the potential to increase organ donation rates, but more research is needed to derive neuroprognostication rules to guide clinical decision-making about when to stop extracorporeal cardiopulmonary resuscitation and to evaluate cost-effectiveness.

CONCLUSIONS

All health systems should develop, implement, and evaluate protocols designed to optimise organ donation opportunities for patients who have an out-of-hospital cardiac arrest and failed attempts at resuscitation.

Outcomes of Kidney Perfusion Techniques in Transplantation from Deceased Donors: A Systematic Review and Meta-Analysis

The high demand for organs in kidney transplantation and the expansion of the donor pool have led to the widespread implementation of machine perfusion technologies. In this study, we aim to provide an up-to-date systematic review of the developments in this expanding field over the past 10 years, with the aim of answering the question: "which perfusion technique is the most promising technique in kidney transplantation?" A systematic review of the literature related to machine perfusion in kidney transplantation was performed. The primary outcome measure was delayed graft function (DGF), and secondary outcomes included rates of rejection, graft survival, and patient survival rates after 1 year. Based on the available data, a meta-analysis was performed. The results were compared with data from static cold storage, which is still the standard of care in many centers worldwide. A total of 56 studies conducted in humans were included, and 43 studies reported outcomes of hypothermic machine perfusion (HMP), with a DGF rate of 26.4%. A meta-analysis of 16 studies showed significantly lower DGF rates in the HMP group compared to those of static cold storage (SCS). Five studies reported outcomes of hypothermic machine perfusion + O₂, with an overall DGF rate of 29.7%. Two studies explored normothermic machine perfusion (NMP). These were pilot studies, designed to assess the feasibility of this perfusion approach in the clinical setting. Six studies reported outcomes of normothermic regional perfusion (NRP). The overall incidence of DGF was 71.5%, as it was primarily used in uncontrolled DCD (Maastricht category I-II). Three studies comparing NRP to in situ cold perfusion showed a significantly lower rate of DGF with NRP. The systematic review and meta-analysis provide evidence that dynamic preservation strategies can improve outcomes following kidney transplantation. More recent approaches such as normothermic machine perfusion and hypothermic machine perfusion + O₂ do show promising results but need further results from the clinical setting. This study shows that the implementation of perfusion strategies could play an important role in safely expanding the donor pool.

Uncontrolled donation after cardiac death kidney transplantation: Opportunity to expand the donor pool?

BACKGROUND

Compared to controlled donation after cardiac death (cDCD), uncontrolled DCD (uDCD) kidney transplantation remains an underutilized resource in the United States. However, it is unclear whether long-term allograft outcomes following uDCD are inferior to that of cDCD kidney transplantation.

METHODS

From January 1995 to January 2018, the OPTN/UNOS database was queried to discover all reported cases of uDCD and cDCD kidney transplantation. Primary non-function, delayed graft function, ten-year graft and patient survival were compared among uDCD and cDCD patients.

RESULTS

Rates of primary non-function (4.0% [uDCD] vs. 1.8% [cDCD], P < 0.001) and delayed graft function (51.1% [uDCD] vs. 41.7% [cDCD], P < 0.001) were higher following uDCD transplant. However, ten-year graft survival (47.5% [uDCD] vs. 48.4% [cDCD], P = 0.21) and patient survival were similar to cDCD transplantation (59.4% [uDCD] vs. 59.2% [cDCD], P = 0.32).

CONCLUSION

Although initial allograft outcomes are inferior following uDCD, long-term durability of uDCD kidney allografts is on par to cDCD transplantation. Kidney allografts derived by uDCD may be a viable and durable option to increase the donor pool.

[Association between controlled circulatory death donor waitlisting and waiting time before kidney transplantation in a French center]

INTRODUCTION

Transplantation from controlled donation after circulatory determination of death (cDCD) is a new practice in France. An additional specific consent is required for registration on the cDCD waiting list. The aim of this study is to evaluate the impact of cDCD acceptance on the waiting time for the registered patients on the transplant list.

METHODS

Patients registered on the kidney transplant waiting list for a Death Brain Donor (DBD) kidney transplant between 2018 and 2019 in our center were included. Patients who were candidates for a second kidney transplant or who had already received an organ transplant were not included. The cDCD waiting list registration was authorized by a signed consent of the patient on the day of DBD registration. The primary endpoint was time to renal transplantation.

RESULTS

Of the 315 patients eligible for a cDCD graft at transplant list registration, 152 were registered on the cDCD waiting list. Time to transplantation for these patients was multiplied by 1.42 (95%CI 1.07-1.87) compared with patients not registered for a cDCD graft. The time to transplantation was 2.59 months (95%CI 0.49-4.69) shorter for a 2-year follow-up for cDCD-listed patients. This represents one additional transplant at 6 months for every seven registered patients.

CONCLUSION

cDCD waiting list registration reduced the time to kidney transplantation in France.

Piloting Uncontrolled DCD Organ Donation in the UK; Overview, Lessons and Future Steps

Purpose of Review

We explore how to develop Maastricht category I and II donation in the UK. We discuss lessons learned from previous UK pilots and define future steps in the journey to establishing a sustainable uDCD programme in the UK.

Recent Findings

The emergence of normothermic regional perfusion (NRP) as a successful strategy in cDCD donation with excellent clinical results creates the optimal platform for the development of a uDCD programme. Coordinated logistics with ambulance services and ED departments, embedded donor coordination in ED, public acceptance and wider discussion on acceptable peri-mortem interventions are key for future developments.

Summary

A uDCD programme in the UK is feasible. Despite an increase in public awareness and recent changes in legislation, there remain several challenges. Recent advances in perfusion and preservation and an established national retrieval infrastructure, create the premises for future sustainable developments.

Novel Ex-Vivo Thrombolytic Reconditioning of Kidneys Retrieved 4 to 5 Hours After Circulatory Death

BACKGROUND

Due to organ shortage, many patients do not receive donor organs. The present novel thrombolytic technique utilizes organs from donors with uncontrolled donation after circulatory deaths (uDCD), with up to 4-5 h warm ischemia, without advanced cardiopulmonary resuscitation (aCPR) or extracorporeal circulation (EC) after death.

METHODS

The study group of pigs (n = 21) underwent simulated circulatory death. After 2 h, an ice slush was inserted into the abdomen. Kidneys were retrieved 4.5 h after death. Lys-plasminogen, antithrombin-III (ATIII), and alteplase (tPA) were injected through the renal arteries on the back table. Subsequent ex vivo perfusion at 15 °C was continued for 3 h, followed by 3 h with red blood cells (RBCs) at 32 °C. Perfusion outcome and histology were compared between uDCD kidneys, receiving no thrombolytic treatment (n = 8), and live donor kidneys (n = 7). The study kidneys were then transplanted into pigs as autologous grafts with a single functioning autologous kidney as the only renal support. uDCD control pigs (n = 8), receiving no ex vivo perfusion, served as controls.

RESULTS

Vascular resistance decreased to <200 mmHg/mL/min ( P < 0.0023) and arterial flow increased to >100 mL/100 g/min ( P < 0.00019) compared to controls. In total 13/21 study pigs survived for >10 days, while all uDCD control pigs died. Histology was preserved after reconditioning, and the creatinine level after 10 days was next to normal.

CONCLUSIONS

Kidneys from extended uDCD, not receiving aCPR/EC, can be salvaged using thrombolytic treatment to remove fibrin thrombi while preserving histology and enabling transplantation with a clinically acceptable early function.

Ethical Issues Related to Donation and Transplantation of Donation After Circulatory Determination of Death Donors

With the continuing disparity between organ supply to match the increasing demand for kidney transplants in patients with renal failure, donation after the circulatory determination of death (DCDD) has become an important and increasing global source of kidneys for clinical use. The concern that the outcomes of controlled DCDD donor kidney transplants were inferior to those obtained from donors declared dead by neurologic criteria has largely diminished because large-scale registry and single-center reports consistently have reported favorable outcomes. For uncontrolled DCDD kidney transplants, outcomes are correspondingly acceptable, although there is a greater risk of primary nonfunction. The potential of DCDD remains unrealized in many countries because of the ethical concerns and resource implications in the utilization of these donor kidneys for transplantation. In this review, we discuss the origin and definitions of DCDD donors, and examine the long-term outcomes of transplants from DCDD donor kidneys. We discuss the controversies, challenges, and ethical and legal barriers in the acceptance of DCDD, including the complexities of implementing and sustaining controlled and uncontrolled DCDD donor programs. The lessons learned from global leaders will assist a wider international recognition, acceptance, and development of DCDD transplant programs that will noticeably facilitate and address the global shortages of kidneys for transplantation, and ensure the opportunity for people who had indicated their desires to become organ donors fulfill their final wishes.

Alloimmune Risk Stratification for Kidney Transplant Rejection

Different types of kidney transplantations are performed worldwide, including biologically diverse donor/recipient combinations, which entail distinct patient/graft outcomes. Thus, proper immunological and non-immunological risk stratification should be considered, especially for patients included in interventional randomized clinical trials. This paper was prepared by a working group within the European Society for Organ Transplantation, which submitted a Broad Scientific Advice request to the European Medicines Agency (EMA) relating to clinical trial endpoints in kidney transplantation. After collaborative interactions, the EMA sent its final response in December 2020, highlighting the following: 1) transplantations performed between human leukocyte antigen (HLA)-identical donors and recipients carry significantly lower immunological risk than those from HLA-mismatched donors; 2) for the same allogeneic molecular HLA mismatch load, kidney grafts from living donors carry significantly lower immunological risk because they are better preserved and therefore less immunogenic than grafts from deceased donors; 3) single-antigen bead testing is the gold standard to establish the repertoire of serological sensitization and is used to define the presence of a recipient's circulating donor-specific antibodies (HLA-DSA); 4) molecular HLA mismatch analysis should help to further improve organ allocation compatibility and stratify immunological risk for primary alloimmune activation, but without consensus regarding which algorithm and cut-off to use it is difficult to integrate information into clinical practice/study design; 5) further clinical validation of other immune assays, such as those measuring anti-donor cellular memory (T/B cell ELISpot assays) and non-HLA-DSA, is needed; 6) routine clinical tests that reliably measure innate immune alloreactivity are lacking.

Similar Results in Liver Transplantation From Controlled Donation After Circulatory Death Donors With Normothermic Regional Perfusion and Donation After Brain Death Donors: A Case-Matched Single-Center Study

Although good results have been reported with the use of normothermic regional perfusion (NRP) in controlled donation after circulatory death (cDCD) liver transplantation (LT), there is a lack of evidence to demonstrate similar results to donation after brain death (DBD). We present a single-center retrospective case-matched (1:2) study including 100 NRP cDCD LTs and 200 DBD LTs and a median follow-up of 36 months. Matching was done according to donor age, recipient Model for End-Stage Liver Disease score, and cold ischemia time. The following perioperative results were similar in both groups: alanine transaminase peaks of 909 U/L in the DBD group and 836 U/L in the cDCD group and early allograft disfunction percentages of 21% and 19.2%, respectively. The 1-year and 3-year overall graft survival for cDCD was 99% and 93%, respectively, versus 92% and 87%, respectively, for DBD (P = 0.04). Of note, no cases of primary nonfunction or ischemic-type biliary lesion were observed among the cDCD grafts. Our results confirm that NRP cDCD LT meets the same outcomes as those obtained with DBD LT and provides evidence to support the idea that cDCD donors per se should no longer be considered as "marginal donors" when recovered with NRP.

A systematic review and meta-analyses of regional perfusion in donation after circulatory death solid organ transplantation

In donation after circulatory death (DCD), (thoraco)abdominal regional perfusion (RP) restores circulation to a region of the body following death declaration. We systematically reviewed outcomes of solid organ transplantation after RP by searching PubMed, Embase, and Cochrane libraries. Eighty-eight articles reporting on outcomes of liver, kidney, pancreas, heart, and lung transplants or donor/organ utilization were identified. Meta-analyses were conducted when possible. Methodological quality was assessed using National Institutes of Health (NIH)-scoring tools. Case reports (13/88), case series (44/88), retrospective cohort studies (35/88), retrospective matched cohort studies (5/88), and case-control studies (2/88) were identified, with overall fair quality. As blood viscosity and rheology change below 20 °C, studies were grouped as hypothermic (HRP, ≤20 °C) or normothermic (NRP, >20 °C) regional perfusion. Data demonstrate that RP is a safe alternative to in situ cold preservation (ISP) in uncontrolled and controlled DCDs. The scarce HRP data are from before 2005. NRP appears to reduce post-transplant complications, especially biliary complications in controlled DCD livers, compared with ISP. Comparisons for kidney and pancreas with ISP are needed but there is no evidence that NRP is detrimental. Additional data on NRP in thoracic organs are needed. Whether RP increases donor or organ utilization needs further research.

Comparison of in situ preservation techniques for kidneys from donors after circulatory death: a systematic review and meta-analysis

Background

Several techniques have been developed to reduce the warm ischaemic injury of donation after circulatory death (DCD) organs before procurement. There are scarce data about the in situ preservation techniques for kidney graft outcomes. The aim of this systematic review was to evaluate the best in situ preservation method for kidney graft outcomes from organs obtained from controlled and uncontrolled DCD.

Methods

A systematic review of the PubMed (MEDLINE), Embase, LILACS and Cochrane databases was conducted. Studies that compare two or more in situ preservation techniques were identified and included. Only studies which provided enough data to calculate odds ratio were eligible for meta-analysis. PROSPERO registration: CRD42020179598.

Results

The search strategy yielded 7,121 studies. Ultimately, 14 retrospective studies were included. Because of heterogeneity, the included studies provided weak evidence that normothermic regional perfusion (NRP) is the best in situ preservation technique in terms of delayed graft function (DGF) rates. Regarding primary nonfunction (PNF), we carried out a meta-analysis of 10 studies with a pooled OR of 0.83 (95% CI: 0.40-1.71), for the NRP. In regard to DGF, pooled OR for NRP was 0.36 (95% CI: 0.25-0.54).

Conclusions

NRP in the DCD donor could improve kidney graft function and be considered the in situ preservation technique of choice for abdominal organs.

Kidney Transplants in Controlled Donation Following Circulatory Death, or Maastricht Type III Donors, With Abdominal Normothermic Regional Perfusion, Optimizing Functional Outcomes

Supplemental Digital Content is available in the text.

Background.

Warm ischemia time and ischemia-reperfusion damage result in higher rates of delayed graft function and primary nonfunction in kidney transplants (KTs) from controlled donation after circulatory death (cDCD). This study aimed to assess early and late kidney function and patient and graft survival of KT from cDCD preserved with normothermic regional perfusion (NRP) and to compare with KT from brain death donors (DBDs) and cDCD preserved with rapid recovery (RR).

Methods.

Patients who received a KT at our institution from 2012 to 2018 were included, with a minimum follow-up period of 1 y. They were categorized by donor type and conditioning methods: DBD, cDCD with NRP, and cDCD with RR. Early and late graft function, along with patient and graft survival were analyzed in all groups.

Results.

A total of 182 KT recipients were included in the study (98 DBD and 84 cDCD). Out of the cDCDs, 24 kidneys were recovered with the use of NRP and 62 with RR; 22 of the 24 kidneys were ultimately transplanted. The cDCD using NRP group showed lower rates of delayed graft function compared with the cDCD with RR group (36.3% versus 46.7%, P = 0.01). Also, primary nonfunction rates were lower in the cDCD using NRP group (4.5% versus 6.4% cDCD-RR and 10.2% DBD). Patient survival rates were >90% in all groups. No differences were found in graft survival rates at 1 y.

Conclusions.

The use of abdominal NRP improves early function recovery of KT from cDCD, making their outcomes comparable with those of DBD.

Transplantation of kidneys after normothermic perfusion: A single center experience

BACKGROUND

In order to expand the pool of usable donors from circulatory death (DCD) there is increasing interest in normothermic regional perfusion (NRP) to assess and improve liver viability.^1,2 NRP may also improve outcomes in kidney transplantation.We present our single center experience of outcomes in imported kidneys following NRP.

METHODS

Data was obtained from a prospectively maintained database between December 2012 and September 2018. Primary endpoints were incidence of delayed graft function (DGF) and estimated glomerular filtration rate (eGFR).

RESULTS

Six-hundred and thirty-two decease donor kidneys were transplanted, 229 from DCD donors, 29 of which had NRP. The DGF rate was lower for NRP versus DCD (six of 29, 20.7% vs. 70 of 200, 35.0%) with reduced duration of DGF. Multivariate analysis demonstrated transplant type to be a statistically significant independent predictor of eGFR at 7 and 14 days. Early transplant function in NRP kidneys was comparable to DBD. There were no graft losses within 30 days in the NRP group. One-year graft loss rate was 3.4% for NRP and 6.0% for standard DCD.

CONCLUSION

This data suggests NRP is safe, and reduces rates of DGF and improves early renal transplant function.

Outcomes for circulatory death and brainstem death pancreas transplantation with or without use of normothermic regional perfusion

Simultaneous pancreas and kidney transplantation is the optimum treatment for patients with type 1 diabetes and renal failure, providing survival benefit over deceased donor kidney transplant alone. Here the authors demonstrate that utilization of donation after circulatory death pancreases is a safe approach to expanding the donor pool with equivalent results to donation after brainstem death transplantation. They also demonstrate that pancreas transplantation after normothermic regional perfusion is feasible, but it will require ongoing prospective study to ensure that the benefits seen for liver transplantation do not come at the expense of pancreas transplant outcomes.

Kidney transplantation from donation after circulatory death using abdominal normothermic oxygenated circulation: are the outcomes equivalent?

PURPOSE

To increase the pool of kidneys available for transplantation, a renewed interest in donation after circulatory death (DCD) has emerged. This study aims to determine the outcomes of kidney transplantation from DCD after abdominal normothermic oxygenated circulation (ANOR) support.

METHODS

From January 2016 to December 2018, 58 kidneys were implanted from uncontrolled DCD after ANOR support. We performed an observational prospective study, assessing graft function and cumulative incidence of surgical complications. A descriptive analysis was conducted. Potential determinants of the outcomes were evaluated, including donor and receptor gender and age, and warm and cold ischemia times. Regression coefficients (β) and odds ratio (OR) were calculated with 95% confidence intervals. A p-value < 0.05 was considered statistically significant. Statistical analysis was accomplished using Stata 11.0 software.

RESULTS

The median follow-up time was 31.2 months. Delayed graft function (DGF) was evident in 80%, with a mean Cr one month after transplantation of 1.81 mg/dL and 1.33 mg/dL after one year. Primary non-function (PNF) occurred in 5.2% of cases. Male donors were associated with a lower DGF (OR = 0.21, p < 0.05), and a higher donor age was a predictor of poorer graft function at one year (β = - 0.88, p < 0.05). Surgical complications occurred in 31% patients, predominantly vascular. Warm ischemia time superior to 60 min correlated with a higher risk of surgical complications (OR = 11.33, p < 0.05).

CONCLUSION

Kidney transplantation from DCD is a valuable option, allowing an improvement in the balance between patients waiting for a transplant and the available kidneys.

Abdominal Normothermic Regional Perfusion in Donation After Circulatory Death: A Systematic Review and Critical Appraisal

BACKGROUND

Abdominal normothermic regional perfusion (aNRP) for donation after circulatory death is an emerging organ preservation technique that might lead to increased organ utilization per donor by facilitating viability testing, improving transplant outcome by early reversal of ischemia, and decreasing the risk of unintentional surgical damage. The aim of the current review is to evaluate the recent literature on the added value of aNRP when compared to local standard perfusion technique.

METHODS

The Preferred Reporting Items for Systematic reviews and Meta-Analyses guideline for systematic reviews was used, and relevant literature databases were searched. Primary outcomes were organ utilization rate and patient and graft survival after 1 year. Secondary outcomes included delayed graft function, primary nonfunction, serum creatinine, and biliary complications.

RESULTS

A total of 24 articles were included in this review. The technique is unanimously reported to be feasible and safe, but the available studies are characterized by considerable heterogeneity and bias.

CONCLUSIONS

Uniform reported outcome measures are needed to draw more definitive conclusions on transplant outcomes and organ utilization. A randomized controlled trial comparing aNRP with standard procurement technique in donation after circulatory death donors would be needed to show the added value of the procedure and determine its place among modern preservation techniques.

Kidney Transplant From Uncontrolled Donation After Circulatory Death: Contribution of Normothermic Regional Perfusion

BACKGROUND

The French uncontrolled donors after circulatory death (DCD) protocol restricts donor age to <55 years, no-flow time to <30 minutes, and functional warm ischemia time to <150 minutes. In situ kidney perfusion can be performed at either 4°C (in situ cooling [ISC]) or 33-36°C (normothermic regional perfusion [NRP]). Hypothermic machine perfusion is systematically used. Only nonimmunized first transplant recipients were eligible. To improve the management of uncontrolled DCD, we tried to identify factors predictive of outcome.

METHODS

We identified all kidney transplants from uncontrolled DCD between 2007 and 2014 from the French Transplant Registry. Risk factors for primary nonfunction (PNF; n = 37) and poor renal function (estimated glomerular filtration rate < 30 mL/min or graft loss at 1 y, n = 66) were analyzed by using a multivariate logistic model.

RESULTS

This study analyzed 499 kidney transplantations, 50% of which were performed with NRP. Mean functional warm ischemia time was 135 minutes. Mean cold ischemia time was 14 hours. The principal PNF risk factor was young donor age (odds ratio [OR] = 0.95; P = 0.002). A sensitivity analysis showed a higher risk of PNF with ISC than with NRP (OR = 4.5; P = 0.015). Risk factors for poor renal function were donor body mass index (OR = 1.2; P < 0.001) and ISC versus NRP. Univariate analysis of uncontrolled DCD-specific risk factors showed no-flow time, functional warm time, and cold ischemia time did not affect the risk of PNF or poor renal function.

CONCLUSIONS

Uncontrolled DCD kidneys are an additional source of valuable transplants. NRP appears to decrease graft failure by restoring oxygenated blood as the first step of preconditioning.

Uncontrolled Donation After Circulatory Death: A Unique Opportunity

Uncontrolled donation after circulatory death (uDCD) refers to donation from persons who die following an unexpected and unsuccessfully resuscitated cardiac arrest. Despite the large potential for uDCD, programs of this kind only exist in a reduced number of countries with a limited activity. Barriers to uDCD are of a logistical and ethical-legal nature, as well as arising from the lack of confidence in the results of transplants from uDCD donors. The procedure needs to be designed to reduce and limit the impact of the prolonged warm ischemia inherent to the uDCD process, and to deal with the ethical issues that this practice poses: termination of advanced cardiopulmonary resuscitation, extension of advanced cardiopulmonary resuscitation beyond futility for organ preservation, moment to approach families to discuss donation opportunities, criteria for the determination of death, or the use of normothermic regional perfusion for the in situ preservation of organs. Although the incidence of primary nonfunction and delayed graft function is higher with organs obtained from uDCD donors, overall patient and graft survival is acceptable in kidney, liver, and lung transplantation, with a proper selection and management of both donors and recipients. Normothermic regional perfusion has shown to be critical to achieve optimal outcomes in uDCD kidney and liver transplantation. However, the role of ex situ preservation with machine perfusion is still to be elucidated. uDCD is a unique opportunity to improve patient access to transplantation therapies and to offer more patients the chance to donate organs after death, if this is consistent with their wishes and values.

Strict selection criteria in uncontrolled donation after circulatory death provide excellent long-term kidney graft survival

BACKGROUND

We aimed to report our experience in uncontrolled donation after circulatory death (uDCD) kidney transplantation applying a strict donor selection and preservation criteria.

METHODS

All kidney recipients received a graft from a local uDCD. As controls, we included all renal transplants from local standard criteria donation after brain death (SDBD) donors. Normothermic regional perfusion was the preservation method in all cases.

RESULTS

A total of 19 kidneys from uDCD donors were included and 67 controls. Delayed graft function (DGF) was higher in the uDCD group (42.1% vs 17.9%; P = .033), whereas no differences were observed in primary nonfunction (0% cases vs 3% controls; P = .605). The estimated glomerular filtration rate was identical in both groups. No differences were observed in graft survival censored for death between the uDCD and the SDBD groups at 1-year (100% vs 95%) or 5-year follow-up (92% vs 91%). uDCD kidney recipients did not have higher risk of graft loss in the multivariate analysis adjusted by recipient age, cold ischemic time, presence of DGF, and second kidney transplant (HR: 0.4; 95% CI 0.02-6; P = .509).

CONCLUSIONS

Obtaining renal grafts from uDCD is feasible in a small city and provides similar outcomes compared to standard DBD donors.

Transplanting Marginal Organs in the Era of Modern Machine Perfusion and Advanced Organ Monitoring

Organ transplantation is undergoing profound changes. Contraindications for donation have been revised in order to better meet the organ demand. The use of lower-quality organs and organs with greater preoperative damage, including those from donation after cardiac death (DCD), has become an established routine but increases the risk of graft malfunction. This risk is further aggravated by ischemia and reperfusion injury (IRI) in the process of transplantation. These circumstances demand a preservation technology that ameliorates IRI and allows for assessment of viability and function prior to transplantation. Oxygenated hypothermic and normothermic machine perfusion (MP) have emerged as valid novel modalities for advanced organ preservation and conditioning. Ex vivo prolonged lung preservation has resulted in successful transplantation of high-risk donor lungs. Normothermic MP of hearts and livers has displayed safe (heart) and superior (liver) preservation in randomized controlled trials (RCT). Normothermic kidney preservation for 24 h was recently established. Early clinical outcomes beyond the market entry trials indicate bioenergetics reconditioning, improved preservation of structures subject to IRI, and significant prolongation of the preservation time. The monitoring of perfusion parameters, the biochemical investigation of preservation fluids, and the assessment of tissue viability and bioenergetics function now offer a comprehensive assessment of organ quality and function ex situ. Gene and protein expression profiling, investigation of passenger leukocytes, and advanced imaging may further enhance the understanding of the condition of an organ during MP. In addition, MP offers a platform for organ reconditioning and regeneration and hence catalyzes the clinical realization of tissue engineering. Organ modification may include immunological modification and the generation of chimeric organs. While these ideas are not conceptually new, MP now offers a platform for clinical realization. Defatting of steatotic livers, modulation of inflammation during preservation in lungs, vasodilatation of livers, and hepatitis C elimination have been successfully demonstrated in experimental and clinical trials. Targeted treatment of lesions and surgical treatment or graft modification have been attempted. In this review, we address the current state of MP and advanced organ monitoring and speculate about logical future steps and how this evolution of a novel technology can result in a medial revolution.

Machine perfusion in abdominal organ transplantation: Current use in the Netherlands

Scarcity of donor organs and the increment in patients awaiting a transplant increased the use of organs from expanded criteria donors or donation after circulatory death. Due to the suboptimal outcomes of these donor organs, there is an increased interest in better preservation methods, such as ex vivo machine perfusion or abdominal regional perfusion to improve outcomes. This state-of-the-art review aims to discuss the available types of perfusion techniques, its potential benefits and the available evidence in kidney, liver and pancreas transplantation. Additionally, translational steps from animal models towards clinical studies will be described, as well as its application to clinical practice, with the focus on the Netherlands. Despite the lack of evidence from randomized controlled trials, currently available data suggest especially beneficial effects of normothermic regional perfusion on biliary complications and ischemic cholangiopathy after liver transplantation. For ex vivo machine perfusion in kidney transplantation, hypothermic machine perfusion has proven to be beneficial over static cold storage in a randomized controlled trial, while normothermic machine perfusion is currently under investigation. For ex vivo machine perfusion in liver transplantation, normothermic machine perfusion has proven to reduce discard rates and early allograft dysfunction. In response to clinical studies, hypothermic machine perfusion for deceased donor kidneys has already been implemented as standard of care in the Netherlands.

The development of a predictive model of graft function in uncontrolled donors after circulatory death: validity of a pulsatile renal preservation machine cut-off value for kidney acceptance

BACKGROUND

The criteria for kidney suitability in uncontrolled donors after circulatory death (uDCD) procured after regional normothermic perfusion are based on macroscopic appearance and renal haemodynamic values with final renal resistance (FRR). However, these criteria have not been analysed to predict the future graft function. This study presents a model to predict the outcome in uDCD kidneys and define the predictive FRR value.

METHODS

All uDCD kidney transplants performed in our hospital from 2004 to 2016 were included. Donors and recipients and pre-transplantation data are described. The endpoint was glomerular filtration rate (GFR) ≥30 mL/min at 6 months after transplantation.

RESULTS

A total of 194 recipients were included. FRR in donors ≥60 years old was (mean ± SD) 0.27 ± 0.11 versus 0.22 ± 0.09 mmHg/mL/min in donors <60 years (P = 0.042). Kidney survival was 88.2% versus 84% at 12 months and 60.7% versus 30.8% at 120 months (P = 0.067). For the group of recipients from donors ≥60 years, the FRR was 0.37 ± 0.08 mmHg/mL/min in the GFR <30 mL/min group versus 0.18 ± 0.06 mmHg/mL/min in the GFR ≥30 mL/min group (P < 0.001). The value FRR ≥0.3 mmHg/mL/min predicts 59-79% of GFR <30 mL/min [odds ratio = 2.16, 95% confidence interval (CI) 1.80-6.40; P < 0.001]. The predictive accuracy of FRR for GFR by ROC curve was 0.968 (95% CI). The best cut-off for FRR was 0.3 mmHg/mL/min to predict GFR at 6 months with a sensitivity of 67%, specificity of 100%, positive predictive value of 83% and negative predictive value of 92%.

CONCLUSIONS

Our results suggest that in uDCD donors the combination of donor age ≥60 years together with FRR ≥0.3 mmHg/mL/min could predict poor outcome at 6 months after transplantation in low immunological risk recipients.

Challenges in the development and implementation of a healthcare system based extracorporeal cardiopulmonary resuscitation (ECPR) program for the treatment of out of hospital cardiac arrest

INTRODUCTION

Extracorporeal cardiopulmonary resuscitation (ECPR) can treat cardiac arrest refractory to conventional therapies. Many institutions are interested in developing their own ECPR program. However, there may be challenges in logistics and implementation.

AIMS

The aim of our protocol was to demonstrate that an ECPR team was feasible within our healthcare system and that the identification of UPMC Presbyterian as a receiving center allowed for successful treatment within 30 min from EMS dispatch.

METHODS

We developed out of hospital cardiac arrest (OHCA) ECPR protocols for Emergency Medical Services (EMS), EMS communications, and our in-hospital ECPR team. Inclusion criteria indentified patients with a potentially reversible arrest etiology and high probability of recoverable brain injury using a simple checklist: witnessed collapse, layperson CPR, initial shockable rhythm, and age 18-60 years. We trained local EMS crews to screen patients and reviewed the criteria with a Medic Command Physician prior to transport to our hospital.

RESULTS

From October 2015 to March 31st 2018, EMS treated 1165 EMS OHCA cases, transported 664 (57%) to a local hospital, and transported 120 (10%) to our institution. Of these, five (4.1%) patients underwent ECPR. Among excluded cases, 64 (53%) had nonshockable rhythms, 48 (40%) were unwitnessed arrests, 50 (42%) were over age 60 and the remaining 20 (17%) had no documented reasons for exclusion. For ECPR cases, median pre-hospital CPR duration was 26 [IQR 25-40] min. Four patients (80%) received mechanical CPR. Interval from arrest to arrival on scene was 5 [IQR 4-6] min and interval from radio call to activation of ECPR was 13 [IQR 7-21] min. Interval from EMS dispatch to departure from scene was 20 [IQR 19-21] min. Time from EMS dispatch to initiation of ECPR was 63 [IQR 59-69] min.

CONCLUSIONS

ECPR is an infrequent occurrence in EMS practice. Most apparently eligible patients did not get ECPR, highlighting the need for ongoing programmatic development, provider education, and qualitative work exploring barriers to implementation.

Preventing acute kidney injury during transplantation: the application of novel oxygen carriers

INTRODUCTION

Delayed graft function (DGF) has a significant impact on kidney transplantation outcome. One of the underlying pivotal mechanisms is organ preservation and associated hypothermia and biochemical alteration.

AREAS COVERED

This paper focuses on organ preservation and its clinical consequences and describes 1. A comprehensive presentation of the pathophysiological mechanism involved in delayed graft function development; 2. The impact on endothelial cells and microvasculature integrity and the consequences on transplanted organ outcome; 3. The reassessment of dynamic organ preservation motivated by the growing use of extended criteria donors and the interest in the potential of normothermia; 4. The role of oxygenation during dynamic preservation; and 5. Novel oxygen carriers and their proof of concept in transplantation, among which M101 (HEMO₂life®) is currently the most extensively investigated.

EXPERT OPINION

Metabolic disturbances and imbalance of oxygen supply during preservation highlight the importance of providing oxygen. Normothermia, permitted by recent advances in machine perfusion technology, appears to be the leading edge of preservation technology. Several oxygen transporters are compatible with normothermia; however, only M101 also demonstrates compatibility with standard hypothermic preservation.

Uncontrolled donation after circulatory death: A cohort study of data from a long-standing deceased-donor kidney transplantation program

Despite good long-term outcomes of kidney transplants from controlled donation after circulatory death (DCD) donors, there are few uncontrolled DCD (uDCD) programs. This longitudinal study compares outcomes for all uDCD (N = 774) and all donation after brain death (DBD) (N = 613) kidney transplants performed from 1996 to 2015 at our center. DBD transplants were divided into those from standard-criteria (SCD) (N = 366) and expanded-criteria (N = 247) brain-dead donors (ECD). One-, 5-, and 10-year graft survival rates were 91.7%, 85.7%, and 80.6% for SCD; 86.0%, 75.8%, and 61.4% for ECD; and 85.1%, 78.1%, and 72.2% for uDCD, respectively. Graft survival was worse in recipients of uDCD kidneys than of SCD (P = .004) but better than in transplants from ECD (P = .021). The main cause of graft loss in the uDCD transplants was primary nonfunction. Through logistic regression, donor death due to pulmonary embolism (OR 4.31, 95% CI 1.65-11.23), extrahospital CPR time ≥75 minutes (OR1.94, 95%CI 1.18-3.22), and in-hospital CPR time ≥50 minutes (OR 1.79, 95% CI 1.09-2.93) emerged as predictive factors of primary nonunction. According to the outcomes of our long-standing kidney transplantation program, uDCD could help expand the kidney donor pool.

The future of organ perfusion and re-conditioning

Organ preservation and re‐conditioning using machine perfusion technologies continue to generate promising results in terms of viability assessment, organ utilization and improved initial graft function. Here, we summarize the latest findings and study the results of ex‐vivo/ex‐situ hypothermic (HMP) and normothermic machine perfusion (NMP) in the area of abdominal organ transplantation (kidney, liver, pancreas and intestine). We also consider the potential role of normothermic regional perfusion (NRP) to re‐condition donors after circulatory death organs before retrieval. The findings from clinical studies reported to date suggest that machine perfusion will offer real benefits when compared with conventional cold preservation. Several randomized trials are expected to report their findings within the next 2 years which may shed light on the relative merits of different perfusion methods and could indicate which perfusion parameters may be most useful to predict organ quality and viability. Further work is needed to identify composite endpoints that are relevant for transplanted organs that have undergone machine preservation. Multi‐centre trials to compare and analyse the combinations of NRP followed by HMP and/or NMP, either directly after organ retrieval using transportable devices or when back‐to‐base, are needed. The potential applications of machine preservation technology beyond the field of solid organ transplantation are also considered.

Defining the optimal duration for normothermic regional perfusion in the kidney donor: A porcine preclinical study

Kidneys from donation after circulatory death (DCD) are highly sensitive to ischemia-reperfusion injury and thus require careful reconditioning, such as normothermic regional perfusion (NRP). However, the optimal NRP protocol remains to be characterized. NRP was modeled in a DCD porcine model (30 minutes of cardiac arrest) for 2, 4, or 6 hours compared to a control group (No-NRP); kidneys were machine-preserved and allotransplanted. NRP appeared to permit recovery from warm ischemia, possibly due to an increased expression of HIF1α-dependent survival pathway. At 2 hours, blood levels of ischemic injury biomarkers increased: creatinine, lactate/pyruvate ratio, LDH, AST, NGAL, KIM-1, CD40 ligand, and soluble-tissue-factor. All these markers then decreased with time; however, AST, NGAL, and KIM-1 increased again at 6 hours. Hemoglobin and platelets decreased at 6 hours, after which the procedure became difficult to maintain. Regarding inflammation, active tissue-factor, cleaved PAR-2 and MCP-1 increased by 4-6 hours, but not TNF-α and iNOS. Compared to No-NRP, NRP kidneys showed lower resistance during hypothermic machine perfusion (HMP), likely associated with pe-NRP eNOS activation. Kidneys transplanted after 4 and 6 hours of NRP showed better function and outcome, compared to No-NRP. In conclusion, our results confirm the mechanistic benefits of NRP and highlight 4 hours as its optimal duration, after which injury markers appear.

Donation after circulatory death and its expansion in Spain

PURPOSE OF REVIEW

Donation after circulatory death (DCD) is still performed in a limited number of countries. This article summarizes the development of DCD in Spain and presents recent Spanish contributions to gain knowledge on the potential benefits and the practical use of normothermic regional perfusion (nRP).

RECENT FINDINGS

DCD now contributes to 24% of deceased donors in Spain. The development of DCD has been based on an assessment of practices in the treatment of cardiac arrest and end-of-life care to accommodate the option of DCD; the creation of an adequate regulatory framework; and institutional support, professional training and public education. Appropriate posttransplant outcomes have been obtained with organs from both uncontrolled and controlled DCD donors. nRP is increasingly used, with preliminary data supporting improved results compared with other in-situ preservation/recovery approaches. Mobile teams with portable extracorporeal membrane oxygenation devices are making nRP possible in hospitals without these resources. To avoid the possibility of reestablishing brain circulation after the determination of death, a specific methodology has been validated.

SUMMARY

DCD has been successfully developed in Spain following a streamlined process. nRP may become a standard in DCD, although further evidence on the benefits of this technology is eagerly awaited.

Kidney transplant from uncontrolled donation after circulatory death donors maintained by nECMO has long-term outcomes comparable to standard criteria donation after brain death

Uncontrolled donation after circulatory death (uDCD) increases organ availability for kidney transplant (KT) with short-term outcomes similar to those obtained from donation after brain death (DBD) donors. However, heterogeneous results in the long term have been reported. We compared 10-year outcomes between 237 KT recipients from uDCD donors maintained by normothermic extracorporeal membrane oxygenation (nECMO) and 237 patients undergoing KT from standard criteria DBD donors during the same period at our institution. We further analyzed risk factors for death-censored graft survival in the uDCD group. Delayed graft function (DGF) was more common in the uDCD group (73.4% vs 46.4%; P < .01), although glomerular filtration rates at the end of follow-up were similar in the 2 groups. uDCD and DBD groups had similar rates for 10-year death-censored graft (82.1% vs 80.4%; P = .623) and recipient survival (86.2% vs 87.6%; P = .454). Donor age >50 years was associated with graft loss in the uDCD group (hazard ratio: 1.91; P = .058), whereas the occurrence of DGF showed no significant effect. uDCD KT under nECMO support resulted in similar graft function and long-term outcomes compared with KT from standard criteria DBD donors. Increased donor age could negatively affect graft survival after uDCD donation.

Systematic review to assess the possibility of return of cerebral and cardiac activity after normothermic regional perfusion for donors after circulatory death

BACKGROUND

Normothermic regional perfusion (NRP) is a novel technique that aids organ recovery from donors after circulatory death (DCDs). However, ethical concerns exist regarding the potential return of spontaneous cerebral and cardiac activity (ROSCCA). This study aimed to determine the likelihood of ROSCCA in NRP-DCDs of abdominal organs.

METHODS

Extracorporeal cardiopulmonary resuscitation (ECPR) for refractory out-of-hospital cardiac arrest (OOHCA) was identified as a comparator for NRP-DCDs and as a validation cohort. A systematic search identified all articles relating to NRP-DCDs and ECPR-OOHCA. Rates of ROSCCA and survival outcomes (ECPR-OOHCA only) were recorded and analysed according to the duration of no perfusion.

RESULTS

In NRP-DCDs, 12 of 410 articles identified by database searching were eligible for inclusion. There were no instances of ROSCCA recorded among 493 donors. In ECPR-OOHCA, eight of 947 screened articles were eligible for inclusion (254 patients). Where the absence of perfusion exceeded 5 min in ECPR-OOHCA, there were no survivors with a favourable neurological outcome.

CONCLUSION

ROSCCA is unlikely following commencement of NRP and has not occurred to date. Strict observance of the 5-min interval following asystole provides satisfactory assurance that ROSCCA will not occur following NRP.

Uncontrolled deceased cardiac donation: An unutilized source for organ transplantation in the United States

The practice of uncontrolled donation after cardiac death (uDCD) has been met with tepid interest within the United States transplant community. Hesitancy stems largely from fears of eroding public trust due to complex ethical issues involving consent. Beyond ethical concerns, uDCD creates unique logistic challenges to obtain and to preserve organs within a short time frame. This mandates that organ recovery centers be able to rapidly mobilize, and that traditional cold preservation techniques may be inadequate. Proof of effective uDCD organ recovery comes from several European nations, and the frequency of its use is increasing due to early promising results. These scarce resources provide life-saving organs to desperate transplant candidates who otherwise experience high morbidity and mortality on a transplant waitlist. The objective of this review will be to provide an overview of the European experience with uDCD and discuss the unique ethical and logistic challenges associated with its implementation in the United States. Given existing models for it successful use, uDCD remains a poorly utilized source of donors in the United States at this time.

Kidney transplantation from donors after uncontrolled circulatory death: the Spanish experience

Donation after uncontrolled circulatory death (uDCD) refers to donation from persons who have died following cardiac arrest and unsuccessful attempt at resuscitation. We report the Spanish experience of uDCD kidney transplantation, and identify factors related to short-term post-transplant outcomes. The Spanish CORE system compiles data on all donation and transplant procedures in the country. Between 2012-2015, 517 kidney transplants from 288 uDCD donors were performed. The incidence of primary non-function was 10%, and the incidence of delayed graft function was 76%. One-year death-censored graft survival was 87%. In a Cox-Model, donor age ≥ 60 years (odds ratio [OR] 2.7; 95% confidence interval [CI] 1.2-6.1), in situ cooling of kidneys versus normothermic regional perfusion (OR 5.6; 95% CI 2.7-11.5) or hypothermic regional perfusion based on the use of extracorporeal membrane oxygenation devices (OR 4.3; 95% CI 2.1-8.6), and a recipient history of prior kidney transplant (OR 3.5; 95% CI 1.5-8.3) all significantly increased the risk of graft loss during the first year after transplantation. Kidney transplantation from uDCD donors provides acceptable 1-year outcomes, although there is room for improvement. Hypothermic and normothermic regional perfusion strategies are preferable to in situ cooling of kidneys from uDCD donors.

Barriers and Advances in Kidney Preservation

Despite the fact that a significant fraction of kidney graft dysfunctions observed after transplantation is due to ischemia-reperfusion injuries, there is still no clear consensus regarding optimal kidney preservation strategy. This stems directly from the fact that as of yet, the mechanisms underlying ischemia-reperfusion injury are poorly defined, and the role of each preservation parameter is not clearly outlined. In the meantime, as donor demography changes, organ quality is decreasing which directly increases the rate of poor outcome. This situation has an impact on clinical guidelines and impedes their possible harmonization in the transplant community, which has to move towards changing organ preservation paradigms: new concepts must emerge and the definition of a new range of adapted preservation method is of paramount importance. This review presents existing barriers in transplantation (e.g., temperature adjustment and adequate protocol, interest for oxygen addition during preservation, and clear procedure for organ perfusion during machine preservation), discusses the development of novel strategies to overcome them, and exposes the importance of identifying reliable biomarkers to monitor graft quality and predict short and long-term outcomes. Finally, perspectives in therapeutic strategies will also be presented, such as those based on stem cells and their derivatives and innovative models on which they would need to be properly tested.

An integrated program of extracorporeal membrane oxygenation (ECMO) assisted cardiopulmonary resuscitation and uncontrolled donation after circulatory determination of death in refractory cardiac arrest

AIM

To assess the feasibility of an integrated program of extracorporeal cardiopulmonary resuscitation (ECPR) and uncontrolled donation after circulatory determination of death (uDCDD) in refractory cardiac arrest (rCA).

METHODS

Single center, prospective, observational study of selected patients with in-hospital (IHCA) and out-of-hospital (OHCA) rCA occurring in an urban area of ∼1.5 million inhabitants, between October-2016 and May-2018. 65 year old or younger patients without significant bleeding or comorbidities with witnessed nonasystolic cardiac arrests were triaged to ECPR if they had a reversible cause and high quality CPR lasting < 60 min. Otherwise they were considered for uDCDD after a ten minute no touch period using normothermic regional perfusion.

RESULTS

58 patients were included, of which 41 (71%) were OHCA and 18 (31%) had ECPR initiated. Median age was 52 (IQR 45-56) years. Cannulation was successful in 49/58 (84%) cases. Compared to ECPR, patients referred for uDCDD were more frequently OHCA (90 vs. 28%), had bystander CPR (28 vs. 83%) and prolonged low-flow period (40 (35-50) vs. 60 (49-78) min). Survival to hospital discharge with full neurological recovery (cerebral performance category 1) occurred in 6/18 (33%) ECPR patients. uDCDD resulted in transplantation of 44 kidneys.

CONCLUSIONS

An integrated program for rCA consisting of a formal pathway to uDCDD referral in ECPR ineligible patients is feasible. ECPR-referred patients had a reasonable survival with full neurologic recovery. Successful kidney transplantation was achieved with uDCDD.

Cardiac output-based fluid optimization for kidney transplant recipients: a proof-of-concept trial

PURPOSE

Intravenous fluid management for deceased donor kidney transplantation is an important, modifiable risk factor for delayed graft function (DGF). The primary objective of this study was to determine if goal-directed fluid therapy using esophageal Doppler monitoring (EDM) to optimize stroke volume (SV) would alter the amount of fluid given.

METHODS

This randomized, proof-of-concept trial enrolled 50 deceased donor renal transplant recipients. Data collected included patient characteristics, fluid administration, hemodynamics, and complications. The EDM was used to optimize SV in the EDM group. In the control group, fluid management followed the current standard of practice. The groups were compared for the primary outcome of total intraoperative fluid administered.

RESULTS

There was no difference in the mean (standard deviation) volume of intraoperative fluid administered to the 24 control and 26 EDM patients [2,307 (750) mL vs 2,675 (842) mL, respectively; mean difference, 368 mL; 95% confidence interval (CI), - 87 to + 823; P = 0.11]. The incidence of complications in the control and EDM groups was similar (15/24 vs 17/26, respectively; P = 0.99), as was the incidence of delayed graft failure (8/24 vs 11/26, respectively; P = 0.36).

CONCLUSIONS

Goal-directed fluid therapy did not alter the volume of fluid administered or the incidence of complications. This proof-of-concept trial provides needed data for conducting a larger trial to determine the influence of fluid therapy on the incidence in DGF in deceased donor kidney transplantation.

TRIAL REGISTRATION

www.clinicaltrials.gov (NCT02512731). Registered 31 July 2015.

Single Graft Utilization From Donors With Severe Acute Kidney Injury After Circulatory Death

Chronic shortages of organs for transplantation have led to the use of marginal kidneys from donors after circulatory death with acute kidney injury (AKI), but the utilization of kidneys with severe AKI is not well established. We retrospectively analyzed eight kidney transplantation (KTx) cases from donation after circulatory death (DCD) with terminal creatinine (t-Cr) concentrations higher than 10.0 mg/dL and/or oliguria for more than 5 days (AKI network criteria: stage III). Although all patients showed delayed graft function, no cases of primary nonfunction (PNF) were found. Five patients maintained stable renal function for approximately 15.5, 10, 10, 5, and 0.5 years after KTx. Only 1 patient showed biopsy-proven acute rejection. Also, 2 patients developed graft failure: one attributable to chronic antibody mediated rejection at 11.3 years after KTx, and one attributable to recurrence of IgA nephropathy at 4.6 years after KTx. Kidneys with AKI stage III yielded great outcomes without the risk of primary nonfunction and rejection. Although the AKI kidneys were associated with delayed graft function, these results suggest that even the most severe kidneys with AKI stage III from DCD donors can be considered a valid alternative for recipients on a waiting list for KTx.

Uncontrolled donation after circulatory death: comparison of two kidney preservation protocols on graft outcomes

Background

Kidney transplantation following uncontrolled donation after circulatory death (uDCD) presents a high risk of delayed graft function due to prolonged warm ischemia time. In order to minimise the effects of ischemia/reperfusion injury during warm ischemia, normothermic recirculation recently replaced in situ perfusion prior to implantation in several institutions. The aim of this study was to compare these preservation methods on kidney graft outcomes.

Methods

The primary endpoint was the one-year measured graft filtration rate (mGFR). We collected retrospective data from 64 consecutive uDCD recipients transplanted over a seven-year period in a single centre.

Results

Thirty-two grafts were preserved by in situ perfusion and 32 by normothermic recirculation. The mean ± SD mGFR at 1 year post-transplantation was 43.0 ± 12.8 mL/min/1.73 m² in the in situ perfusion group and 53.2 ± 12.8 mL/min/1.73 m² in the normothermic recirculation group (p = 0.01). Estimated GFR levels were significantly higher in the normothermic recirculation group at 12 months (p = 0.01) and 24 months (p = 0.03) of follow-up. We did not find any difference between groups regarding patient and graft survival, delayed graft function, graft rejection, or interstitial fibrosis.

Conclusions

Function of grafts preserved by normothermic recirculation was better at 1 year and the results suggest that this persists at 2 years, although no difference was found in short-term outcomes. Despite the retrospective design, this study provides an additional argument in favour of normothermic recirculation.

Electronic supplementary material

The online version of this article (10.1186/s12882-017-0805-1) contains supplementary material, which is available to authorized users.

PROviding Better ACcess To ORgans: A comprehensive overview of organ-access initiatives from the ASTS PROACTOR Task Force

The American Society of Transplant Surgeons (ASTS) PROviding better Access To Organs (PROACTOR) Task Force was created to inform ongoing ASTS organ access efforts. Task force members were charged with comprehensively cataloguing current organ access activities and organizing them according to stakeholder type. This white paper summarizes the task force findings and makes recommendations for future ASTS organ access initiatives.