Kidney graft outcome and quality (after transplantation) from uncontrolled deceased donors after cardiac arrest

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.

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.

Cold Storage Increases Albumin and Advanced Glycation-End Product-Albumin Levels in Kidney Transplants: A Possible Cause for Exacerbated Renal Damage

Prolonged cold storage (CS) of kidneys is associated with poor renal outcome after transplantation (Tx). We recently showed that in rats (Lewis), proteasome and renal function were severely compromised in kidney transplants subjected to CS (CS/Tx) as compared with those without CS exposure (autotransplanted [ATx]).

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.

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.

Renal cold storage followed by transplantation impairs proteasome function and mitochondrial protein homeostasis

Identifying pathways related to renal cold storage (CS) that lead to renal damage after transplantation (Tx) will help us design novel pathway-specific therapies to improve graft outcome. Our recent report showed that mitochondrial function was compromised after CS alone, and this was exacerbated when CS was combined with Tx (CS/Tx). The goal of this study was to determine whether the proteasome exacerbates mitochondrial dysfunction after CS/Tx. We exposed the kidneys of male Lewis rats (in vivo) and rat renal proximal tubular (NRK) cells (in vitro) to CS/Tx or rewarming (CS/RW), respectively. To compare CS-induced effects, in vivo kidney Tx without CS exposure (autotransplantation; ATx) was also used. Our study provides the first evidence that the chymotrypsin-like (ChT-L) peptidase activity of the proteasome declined only after CS/Tx or CS/RW, but not after CS or ATx. Interestingly, key mitochondrial proteins involved with respiration [succinate dehydrogenase complex, subunit A (SDHA), a complex II subunit, and ATP5B, an ATP synthase/complex V subunit] were detected in the detergent-insoluble fraction after CS/Tx or CS/RW, with compromised complex V activity. Pharmacological inhibition of ChT-L activity in NRK cells decreased the activity of mitochondrial complexes I, II, and V and also increased the levels of SDHA and ATP5B in the insoluble fraction. On the other hand, inhibiting mitochondrial respiration in NRK cells with antimycin A compromised ChT-L function and increased the amounts of SDHA and ATP5B in the insoluble fraction. Our results suggest that mitochondrial respiratory dysfunction during CS precedes compromised ChT-L function after CS/Tx and proteasome dysfunction further alters mitochondrial protein homeostasis and decreases respiration in the kidneys after CS/Tx. Therefore, therapeutics that preserve mitochondrial and proteasome function during CS may provide beneficial outcomes following transplantation.

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.

Similar 5-Year Estimated Glomerular Filtration Rate Between Kidney Transplants From Uncontrolled and Controlled Donors After Circulatory Death-A Dutch Cohort Study

BACKGROUND

Organ shortage persists despite a high rate of donation after circulatory death (DCD) in the Netherlands. The median waiting time for a deceased donor kidney in 2013 was 3.5 years. Most DCD kidneys are from controlled DCD (cDCD; Maastricht category III). Experience with uncontrolled donors after cardiac death (uDCD), that is, donors with an unexpected and irreversible cardiac arrest (Maastricht categories I and II), is increasing; and its effect on transplant outcomes needs evaluation.

METHODS

We used the Dutch Organ Transplantation Registry to include recipients (≥18 years old) from all Dutch centers who received transplants from 2002 to 2012 with a first DCD kidney. We compared transplant outcome in uDCD (n = 97) and cDCD (n = 1441).

RESULTS

Primary nonfunction in uDCD was higher than in the cDCD (19.6% vs 9.6%, P < 0.001, respectively). Delayed graft function was also higher in uDCD than in cDCD, but not significantly (73.7% vs 63.3%, P = .074, respectively). If censored for primary nonfunction, estimated glomerular filtration rates after 1 year and 5 years were comparable between uDCD and cDCD (1 year: uDCD, 44.3 (23.4) mL/min/m and cDCD, 45.8 (24.1) mL/min/m; P = 0.621; 5 years: uDCD, 49.1 (25.6) mL/min/m and cDCD, 47.7 (21.7) mL/min/m; P = 0.686). The differences in primary nonfunction between kidneys from uDCD and cDCD were explained by differences in the first warm ischemic period, cold ischemic time, and donor age.

CONCLUSIONS

We conclude that uDCD kidneys have potential for excellent function and can constitute a valuable extension of the donor pool. However, further efforts are necessary to address the high rate of primary nonfunction.

Organ donation protocols

Organ transplantation improves survival and quality of life in patients with end-organ failure. Waiting lists continue to grow across the world despite remarkable advances in the transplantation process, from the creation of public engagement campaigns to the development of critical pathways for the timely identification, referral, approach, and treatment of the potential organ donor. The pathophysiology of dying triggers systemic changes that are intimately related to organ viability. The intensive care management of the potential organ donor optimizes organ function and improves the donation yield, representing a significant step in reducing the mismatch between organ supply and demand. Different beliefs and cultures reflect diverse legislations and donation practices amongst different countries, creating a challenge to standardized practices. Maintaining public trust is necessary for continued progress in organ donation and transplantation, hence the urge for a joint effort in creating uniform protocols that ensure transparent practices within the medical community.

Uncontrolled donation after circulatory death: European practices and recommendations for the development and optimization of an effective programme

The shortage of organs remains one of the biggest challenges in transplantation. To address this, we are increasingly turning to donation after circulatory death (DCD) donors and now in some countries to uncontrolled DCD donors. We consolidate the knowledge on uncontrolled DCD in Europe and provide recommendations and guidance for the development and optimization of effective uncontrolled DCD programmes.

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

The aim of this study was to compare the outcomes of kidney transplants from uncontrolled DCD (uDCD) with kidney transplants from extended (ECD) and standard criteria donors (SCD). In this multicenter study, we included recipients from uDCD (n = 50), and from ECD (n = 57) and SCD (n = 102) who could be eligible for a uDCD program. We compared patient and graft survival, and kidney function between groups. To address the impact of preservation procedures in uDCD, we compared in situ cold perfusion (ICP) with normothermic regional perfusion (NRP). Patient and graft survival rates were similar between the uDCD and ECD groups, but were lower than the SCD group (P < 0.01). Although delayed graft function (DGF) was more frequent in the uDCD group (66%) than in the ECD (40%) and SCD (27%) groups (P = 0.08 and P < 0.001), graft function was comparable between the uDCD and ECD groups at 3 months onwards post-transplantation. The use of NRP in the uDCD group (n = 19) was associated with a lower risk of DGF, and with a better graft function at 2 years post-transplantation, compared to ICP-uDCD (n = 31) and ECD. In conclusion, the use of uDCD kidneys was associated with post-transplantation results comparable to those of ECD kidneys. NRP preservation may improve the results of uDCD transplantation.

Protocols for uncontrolled donation after circulatory death: a systematic review of international guidelines, practices and transplant outcomes

INTRODUCTION

A chronic shortage of organs remains the main factor limiting organ transplantation. Many countries have explored the option of uncontrolled donation after circulatory death (uDCD) in order to expand the donor pool. Little is known regarding the variability of practices and outcomes between existing protocols. This systematic review addresses this knowledge gap informing policy makers, researchers, and clinicians for future protocol implementation.

METHODS

We searched MEDLINE, EMBASE, and Google Scholar electronic databases from 2005 to March 2015 as well as the reference lists of selected studies, abstracts, unpublished reports, personal libraries, professional organization reports, and government agency statements on uDCD. We contacted leading authors and organizations to request their protocols and guidelines. Two reviewers extracted main variables. In studies reporting transplant outcomes, we added type, quantity, quality of organs procured, and complications reported. Internal validity and the quality of the studies reporting outcomes were assessed, as were the methodological rigour and transparency in which a guideline was developed. The review was included in the international prospective register of systematic reviews (Prospero, CRD42014015258).

RESULTS

Six guidelines and 18 outcome studies were analysed. The six guidelines are based on limited evidence and major differences exist between them at each step of the uDCD process. The outcome studies report good results for kidney, liver, and lung transplantation with high discard rates for livers.

CONCLUSIONS

Despite procedural, medical, economic, legal, and ethical challenges, the uDCD strategy is a viable option for increasing the organ donation pool. Variations in practice and heterogeneity of outcomes preclude a meta-analysis and prevented the linking of outcomes to specific uDCD protocols. Further standardization of protocols and outcomes is required, as is further research into the role of extracorporeal resuscitation and other novel therapies for treatment of some refractory cardiac arrest. It is essential to ensure the maintenance of trust in uDCD programs by health professionals and the public.

Dual kidney transplantation from uncontrolled deceased donors after cardiac arrest: a possible option

Organ shortage is a major problem in organ transplantation. For this reason, transplantation teams have found it necessary to revisit their organ acceptance criteria. Uncontrolled deceased donors after cardiac arrest could increase the donor pool by 20%, but at the same time there is a greater risk of delayed graft function and primary non-function. Dual kidney transplantation is an option when single kidney transplantation cannot be carried out because of lack of organ quality. We report for the first time our four first dual kidney transplantation from uncontrolled deceased donors after cardiac arrest with a follow up longer than 1 year. We described graft outcomes until 5 years, and histology at 3 and 12 months after transplantation. All organs were machine perfused in order to assess their quality leading to a single kidney transplantation or dual kidney transplantation decision. After 1 year of follow up, all grafts were functional with a mean estimated glomerular filtration rate of 44.5 ± 3.3 mL/min/1.73 m(2), and a mean inulin clearance of 43.7 ± 13.6 mL/mn/1.73 m(2). These findings suggest that dual kidney transplantation can represent a viable option for kidneys unsuitable for single kidney transplantation without increasing the rate of surgical complications. Successful transplantation is linked to histological, biological and donor clinical criteria, as well as perfusion parameters.

No-touch time in donors after cardiac death (nonheart-beating organ donation)

PURPOSE OF REVIEW

To evaluate arterial pulselessness and the no-touch time of 5 min in defining irreversible cessation of cardiorespiratory functions in nonheart-beating donation (NHBD).

RECENT FINDINGS

Experimental NHBD studies identified compensatory neurohumoral mechanisms elicited in controlled terminal shock after withdrawal of life support. The neurohumoral mechanisms can preserve the viability of the cardiovascular and central nervous systems by: 1) diverting systemic blood flow from nonvital to vital organs; and 2) maintaining the perfusion pressure (arterial to venous pressure gradient minus interstitial tissue pressure) and microcirculation in vital organs. These compensatory mechanisms cause an early onset of splanchnic hypoperfusion and antemortem ischaemia of transplantable organs and preclude irreversible cessation of cardiorespiratory functions after brief periods of circulatory arrest. Allograft ischaemia is associated with primary nonfunction or delayed function in transplant recipients similar in aetiology to organ dysfunction in the postresuscitation phase of shock.

SUMMARY

In-situ perfusion can reverse ceased cardiac and neurological functions after arterial pulselessness and a no-touch time of 5 min in experimental models. Perfusion pressures are superior to arterial pulselessness in determining reversibility of ceased cardiac and neurological functions in circulatory arrest. Utilizing physiologically relevant circulatory and neurological parameters in NHBD protocols is essential for ascertaining irreversible cessation of vital functions in donors.