Donation after circulatory death today: an updated overview of the European landscape

Indocyanine green fluorescence quantification during normothermic ex situ perfusion for the assessment of porcine liver grafts after circulatory death

Current graft evaluation during normothermic ex situ liver perfusion lacks real-time parameters for predicting posttransplant hepatocyte and biliary function. Indocyanine green (ICG) imaging has been widely used in liver surgery, enabling the visualization of hepatic uptake and excretion through bile using near-infrared light. In this research, porcine livers under various ischemic conditions were examined during a 5-hour normothermic ex situ liver perfusion procedure, introducing ICG at 1 hour through the hepatic artery. These conditions included livers from heart-beating donors, donation after circulatory death (DCD) with warm ischemic durations of 60 minutes (DCD60) and 120 minutes (DCD120), as well as interventions utilizing tissue plasminogen activator in DCD120 cases (each n = 5). Distinct hepatic fluorescence patterns correlated with different degrees of ischemic injury ( p = 0.01). Low ICG uptake in the parenchyma (less than 40% of maximum intensity) was more prevalent in DCD120 (21.4%) compared to heart-beating donors (6.2%, p = 0.06) and DCD60 (3.0%, p = 0.02). Moreover, ICG clearance from 60 minutes to 240 minutes was significantly higher in heart-beating donors (69.3%) than in DCD60 (17.5%, p < 0.001) and DCD120 (32.1%, p = 0.01). Furthermore, thrombolytic intervention using tissue plasminogen activator in DCD120 resulted in noteworthy outcomes, including significantly reduced ALP levels ( p = 0.04) and improved ICG clearance ( p = 0.02) with a trend toward mitigating fibrin deposition similar to DCD60, as well as enhancements in bile production ( p = 0.09). In conclusion, ICG fluorescence imaging during normothermic ex situ liver perfusion provides real-time classification of hepatic vascular and biliary injuries, offering valuable insights for the more accurate selection and postintervention evaluation of marginal livers in transplantation.

Potential organ donors during two years at the second largest hospital in Norway

BACKGROUND

Western Norway has the lowest number of actual deceased organ donors per million inhabitants in Norway. We wished to find the total number of potential donors and donor organs during 2 years at Haukeland University Hospital, the largest hospital in the region, and evaluate where and why potential donors were lost.

METHODS

We evaluated all patients who died at Haukeland University Hospital in 2018-19. We checked if intensive care patients, filling the criteria as organ donors after brain death, became donors, and the reasons why potential donors were lost. We also estimated the number of potential donors after circulatory death. We checked if patients transferred from the intensive care units and patients never admitted to intensive care were potential donors. Location, gender, age, and possible number of organs were registered.

RESULTS

Of 1453 in-hospital deaths, 20 brain-dead patients became actual donors. One brain-dead and two other potential donors, one of them discharged to a bed ward, were not evaluated at the intensive care units. Relatives refused in five patients. Three fulfilled the Norwegian criteria from 2021 as organ donors after circulatory death. Ten potential donors after brain death were never admitted to intensive care and died on neurological or neurosurgical wards. If all potential organ donors were realised, the number of donors would double. The number of transplanted organs would increase less, as organs used per donor would drop from 3.50 to 2.90.

CONCLUSION

Our study cannot explain the low number of donors in our region compared with the rest of Norway. If all potential donations were implemented, the number of actual donors would double. Patients dying outside the intensive care units represent the largest potential source for extra donors, maximally increasing the number of donors by 42%, high-quality livers 44% and kidneys 18%. Introducing organ donation after circulatory death may increase the number of donors by 15% and the number of high-quality livers and kidneys by 12%.

Ethical Issues in Normothermic Regional Perfusion in Controlled Organ Donation After Determination of Death by Circulatory Criteria: A Scoping Review

Normothermic regional perfusion (NRP) is a surgical technique that can improve the quality and number of organs recovered for donation after the determination of death by circulatory criteria. Despite its promise, adoption of NRP has been hindered because of unresolved ethical issues. To inform stakeholders, this scoping review provides an impartial overview of the major ethical controversies surrounding NRP. We undertook this review according to a modified 5-step methodology proposed by Arksey and O'Malley. Publications were retrieved through MEDLINE and Embase. Gray literature was sourced from Canadian organ donation organizations, English-language organ donation organization websites, and through our research networks. Three reviewers independently screened all documents for inclusion, extracted data, and participated in content analysis. Disagreements were resolved through consensus meetings. Seventy-one documents substantively engaging with ethical issues in NRP were included for full-text analysis. We identified 6 major themes encompassing a range of overlapping ethical debates: (1) the compatibility of NRP with the dead donor rule, the injunction that organ recovery cannot cause death, (2) the risk of donor harm posed by NRP, (3) uncertainties regarding consent requirements for NRP, (4) risks to stakeholder trust posed by NRP, (5) the implications of NRP for justice, and (6) NRP's potential to benefits of NRP for stakeholders. We found no agreement on the ethical permissibility of NRP. However, some debates may be resolved through additional empirical study. As decision-makers contemplate the adoption of NRP, it is critical to address the ethical issues facing the technique to ensure stakeholder trust in deceased donation and transplantation systems is preserved.

Major determinants of primary non function from kidney donation after Maastricht II circulatory death: A single center experience

PURPOSE

Organ shortage greatly limits treatment of patients with end-stage chronic kidney. Maastricht type 2 donation after circulatory death (DCD) has been shown to have similar results in long term outcomes in kidney transplantation, when compared with brain dead donation. Our main goal was to assess Maastricht type 2 DCD and evaluate factors that impact on early graft function.

METHODS

A retrospective study was conducted in an ECMO Referral Centre. All patients who received a kidney transplant from Maastricht type 2 DCD were included in study. Early graft function and short term outcomes were assessed.

RESULTS

From October 2017 to December 2022, 47 renal grafts were collected from 24 uDCD donors. Median warm ischemia time was 106 min (94-115), cannulation time was 10 min (8; 20) and duration of extracorporeal reperfusion (ANOR) was 180 min (126-214). Regarding early graft function, 25% had immediate graft function, 63.6% had delayed graft function and 11.4% had primary non-function (PNF). There was a correlation between cannulation time (p = 0.006) and ANOR with PNF (p = 0.016).

CONCLUSIONS

Cannulation time and ANOR were the main factors that correlated with PNF. Better understanding of underlying mechanisms should be sought in future studies to reduce the incidence of PNF.

[Organ donation and organ assessment after primary circulatory death and secondary brain death]

BACKGROUND

The global organ shortage is the biggest obstacle to expand urgently needed liver transplantation activities. In addition to donation after brain death (DBD), donation after primary circulatory death (DCD) has also been introduced in many European countries to increase the number of donated organs.

OBJECTIVE

This article summarizes the legal and ethical aspects of DCD, the practical donation process of DCD, the clinical results of DCD liver transplantation with a special focus on organ assessment before a planned DCD liver transplantation.

RESULTS

In Europe 11 countries have active DCD liver transplantation programs and a total of 1230 DCD liver transplantations were performed in Europe in 2023. The highest proportion of DCD liver transplantations were recorded in Belgium (52.8%), the Netherlands (42.8%) and Switzerland (32.1%). The adequate selection of donors and recipients is crucial in DCD transplantation and the use of DCD livers particularly depends on the preparedness of the healthcare system for routine machine perfusion. The leaders are Belgium, France and Italy which implant around 68-74% of DCD organs. With an adequate organ assessment, the long-term results of DBD and DCD liver transplantations are comparable. To assess mitochondrial damage and thus organ quality, hypothermic oxygenated machine perfusion (HOPE) was introduced and has the secondary benefit of mitochondrial protection through oxygenation. The establishment of aerobic metabolism in mitochondria under hypothermia leads to a reduction of toxic metabolites and the restoration of ATP storage, which subsequently leads to a reperfusion light during implantation.

CONCLUSION

Expanding the donor pool with DCD donors can counteract the global organ shortage. With adequate patient selection and routine organ assessment short-term and also long-term outcomes of DBD and DCD liver transplantation are comparable.

American Society of Transplant Surgeons Normothermic Regional Perfusion Standards: Abdominal

BACKGROUND

Normothermic regional perfusion (NRP) has emerged as a vital technique in organ procurement, particularly in donation after circulatory death (DCD) cases, offering the potential to optimize organ utilization and improve posttransplant outcomes. Recognizing its significance, the American Society of Transplant Surgeons (ASTS) convened a work group to develop standardized recommendations for abdominal NRP in the United States.

METHODS

The workgroup, comprising experts in NRP, DCD, and transplantation, formulated recommendations through a collaborative process involving revisions and approvals by relevant committees and the ASTS council. Four key areas were identified for standardization: Preprocedure communication, NRP procedure, Terminology and documentation, and Mentorship/credentialing.

RESULTS

The recommendations encompass a range of considerations, including preprocedure communication protocols to facilitate informed decision-making by transplant centers and organ procurement organizations, procedural guidelines for NRP teams, uniform terminology to clarify the NRP process, and standards for mentorship and credentialing of NRP practitioners. Specific recommendations address logistical concerns, procedural nuances, documentation requirements, and the importance of ongoing quality assurance.

CONCLUSIONS

The standardized recommendations for abdominal NRP presented in this article aim to ensure consistency, safety, and efficacy in the organ procurement process. By establishing clear protocols and guidelines, the ASTS seeks to enhance organ utilization, honor donor wishes, and uphold public trust in the donation process. Implementation of these recommendations can contribute to the advancement of NRP practices and improve outcomes for transplant recipients.

Donor Evaluation Tool: A New Technology Improves Donor Enrolment on ICU

Uncertainties on the intensive care unit (ICU) regarding the eligibility of a patient to be a potential deceased organ donor may prevent their referral and enrolment in the pathway for organ donation. Healthcare staff may exclude potential donors for medical reasons, which are no longer applicable. Hence, Swisstransplant implemented a digital donor evaluation tool (DET) in 2021, which allows the local hospital's organ donation coordinator to send a direct request to medical advisors (MA) of the organ procurement organization before excluding potential donors. All 156 requests entered in 2022 were analyzed. 117 patients (75.0%) were primarily accepted by the MA as potential donors. Of those 60 patients (51.3%) became actual organ donors. Main reasons for using the DET were questions regarding malignancies (n = 33, 21.2%), infectious diseases (n = 35, 22.4%) and age/co-morbidities (n = 34, 21.8%). The average age of the actual "DET donor" compared to the regularly enrolled, actual "Non-DET donor" was 65.3 ± 15.8 vs. 56.8 ± 17.5 years, respectively (p = 0.008). On average 1.9 ± 1.1 organs compared to 3.2 ± 1.3 organs were retrieved from DET vs. Non-DET donors. In summary, this new digital donor evaluation tool supports reporting and facilitates eligibility decisions in uncertain, complex donor cases, potentially increasing the number of organ donations.

Normothermic Regional Perfusion in Controlled Donation After the Circulatory Determination of Death: Understanding Where the Benefit Lies

Controlled donation after the circulatory determination of death (cDCDD) has emerged as a strategy to increase the availability of organs for clinical use. Traditionally, organs from cDCDD donors have been subject to standard rapid recovery (SRR) with poor posttransplant outcomes of abdominal organs, particularly the liver, and limited organ utilization. Normothermic regional perfusion (NRP), based on the use of extracorporeal membrane oxygenation devices, consists of the in situ perfusion of organs that will be subject to transplantation with oxygenated blood under normothermic conditions after the declaration of death and before organ recovery. NRP is a potential solution to address the limitations of traditional recovery methods. It has become normal practice in several European countries and has been recently introduced in the United States. The increased use of NRP in cDCDD has occurred as a result of a growing body of evidence on its association with improved posttransplant outcomes and organ utilization compared with SRR. However, the expansion of NRP is precluded by obstacles of an organizational, legal, and ethical nature. This article details the technique of both abdominal and thoracoabdominal NRP. Based on the available evidence, it describes its benefits in terms of posttransplant outcomes of abdominal and thoracic organs and organ utilization. It addresses cost-effectiveness aspects of NRP, as well as logistical and ethical obstacles that limit the implementation of this innovative preservation strategy.

Potential for organ donation after controlled circulatory death: a retrospective analysis

Objectives

Despite the discrepancy between demand and availability of organs for transplantation, controlled circulatory death donation has not been implemented in Portugal. This study aimed to estimate the potential increase in organ donation from implementing such a program.

Material and Methods

All deceased patients within the intensive care medicine department at Centro Hospitalar Universitário de São João, throughout the year 2019, were subjected to retrospective analysis. Potential gain was estimated comparing the results with the number of donors and organs collected during the same period at this hospital center. Differences in variables between groups were assessed using t tests for independent samples or Mann-Whitney U tests for continuous variables, and chi-squared tests were used for categorical variables.

Results

During 2019, 152 deaths occurred after withdrawal of life-sustaining therapies, 10 of which would have been potentially eligible for donation after controlled circulatory death. We can anticipate a potential increase of 10 prospective donors, a maximum 21% growth in yearly transplantation activity, with a greater impact on kidney transplantation. For most patients, the time between withdrawal of organ support and death surpassed 120 minutes, an outcome explained by variations in withdrawal of life-sustaining measures and insufficient clinical records, underestimating the potential for controlled circulatory arrest donation.

Conclusion

This study effectively highlights public health benefits of controlled circulatory arrest donation. Legislation allowing donation through this method represents a social gain and enables patients who will never meet brain death criteria to donate organs as part of the end-of-life process in intensive care medicine, within a framework of complete ethical alignment.

Restoring the Organism as a Whole: Does NRP Resurrect the Dead?

The introduction of normothermic regional perfusion (NRP) in controlled donation after circulatory determination of death (cDCDD) protocols is by some regarded as controversial and ethically troublesome. One of the main concerns that opponents have about introducing NRP in cDCDD protocols is that reestablishing circulation will negate the determination of death by circulatory criteria, potentially resuscitating the donor. In this article, I argue that this is not the case. If we take a closer look at the concept of death underlying the circulatory criterion for determination of death, we find that the purpose of the criterion is to show whether the organism as a whole has died. I argue that this purpose is fulfilled by the circulatory criterion in cDCDD protocols, and that applying NRP does not negate the determination of death or resuscitate the donor.

Controlled donation after circulatory death in post-cardiac arrest patients: Estimates from a large registry

BACKGROUND

Controlled donation after circulatory death (cDCD) in post-anoxic brain injury is a valuable source of organs that is still underused in some countries. We assessed the number of potential cDCD donors after out-of-hospital cardiac arrest (OHCA) in Paris and its suburbs and extrapolated the results to the French population.

METHODS

Using the large regional registry of the Great Paris area, we prospectively included all consecutive adults with OHCA with a stable return of spontaneous circulation (ROSC) who ultimately died in the intensive care unit (ICU) after withdrawal of life-sustaining treatments (WLST) due to post anoxic brain injury. The primary endpoint was potential for organ donation by cDCD in this population. The number of potential cDCD donors was calculated and extrapolated to the entire French population.

RESULTS

Between 2011 and 2018, 4638 patients with stable ROSC were admitted to ICUs after OHCA, and 3170 died in ICU, of which 1034 died after WLST due to post-anoxic brain injury. When considering French criteria, 421/1034 patients (41%) would have been potential cDCD donors (55 patients per year in a 4.67 million population). After standardization for age and sex, the potential for cDCD was 515 (95% CI 471-560) patients per year in France corresponding to an annual incidence of 1.18 per 100 000 inhabitants per year.

CONCLUSIONS

Organ donation by cDCD after cardiac arrest could provide a large pool of donors in France.

Predicting time to asystole following withdrawal of life-sustaining treatment: a systematic review

The planned withdrawal of life-sustaining treatment is a common practice in the intensive care unit for patients where ongoing organ support is recognised to be futile. Predicting the time to asystole following withdrawal of life-sustaining treatment is crucial for setting expectations, resource utilisation and identifying patients suitable for organ donation after circulatory death. This systematic review evaluates the literature for variables associated with, and predictive models for, time to asystole in patients managed on intensive care units. We conducted a comprehensive structured search of the MEDLINE and Embase databases. Studies evaluating patients managed on adult intensive care units undergoing withdrawal of life-sustaining treatment with recorded time to asystole were included. Data extraction and PROBAST quality assessment were performed and a narrative summary of the literature was provided. Twenty-three studies (7387 patients) met the inclusion criteria. Variables associated with imminent asystole (<60 min) included: deteriorating oxygenation; absence of corneal reflexes; absence of a cough reflex; blood pressure; use of vasopressors; and use of comfort medications. We identified a total of 20 unique predictive models using a wide range of variables and techniques. Many of these models also underwent secondary validation in further studies or were adapted to develop new models. This review identifies variables associated with time to asystole following withdrawal of life-sustaining treatment and summarises existing predictive models. Although several predictive models have been developed, their generalisability and performance varied. Further research and validation are needed to improve the accuracy and widespread adoption of predictive models for patients managed in intensive care units who may be eligible to donate organs following their diagnosis of death by circulatory criteria.

Demographics of deceased donor renal transplants in Ireland: A 10 year review showing the worrying increase of suicide as a source for organ donation

INTRODUCTION

Kidney transplantation is the treatment of choice for patients with end stage renal disease. The primary aim of this study was to assess the demographics of deceased kidney donors over the last ten years and to assess for gender variations in deceased donor demographics over an extended period.

METHODS

A retrospective data analysis was carried out using data from the national renal transplant database. All deceased donors who donated a kidney between 1st January 2012 and 31st December 2021 were included. Data points extracted included gender, age, cause of death and month of death. Descriptive analyses were carried out using Excel v16.67.

RESULTS

A total of 1219 kidneys from 650 donors were donated over the ten-year period. The mean donor age was 44.01 years (range 1-74 years). The most common cause of death overall was subarachnoid haemorrhage (SAH), which was the cause of death in 27.8 % of donors (n = 180). Male donors accounted for 57.8 % of donors overall (n = 376). Variation in causes of death was observed between male and female donors, and between younger and older donors. 9 % of male deaths were from suicide compared with 5 % of female deaths. 6 % of male deaths were due to a traumatic head injury, with this accounting for 2 % of female deaths. Deaths due to assault made up 2 % of male donor deaths, but were not a cause of death for any female donors.

CONCLUSION

SAH and intracranial bleeds were the most common cause of death in both groups for deceased donor renal transplantation. Incidence of suicide as cause of death in deceased donors is rising in males.

Sowing "seeds of trust": How trust in normothermic regional perfusion is built in a continuum of care

Normothermic regional perfusion (NRP) is a promising technology to improve organ transplantation outcomes by reversing ischemic injury caused by controlled donation after circulatory determination of death. However, it has not yet been implemented in Canada due to ethical questions. These issues must be resolved to preserve public trust in organ donation and transplantation. This qualitative, constructivist grounded theory study sought to understand how those most impacted by NRP perceived the ethical implications. We interviewed 29 participants across stakeholder groups of donor families, organ recipients, donation and transplantation system leaders, and care providers. The interview protocol included a short presentation about the purpose of NRP and procedures in abdomen versus chest and abdomen NRP, followed by questions probing potential violations of the dead donor rule and concerns regarding brain reperfusion. The results present a grounded theory placing NRP within a trust-building continuum of care for the donor, their family, and organ recipients. Stakeholders consistently described both forms of NRP as an ethical intervention, but their rationales were predicated on assumptions that neurologic criteria for death had been met following circulatory death determination. Empirical validation of these assumptions will help ground the implementation of NRP in a trust-preserving way.

Lung Transplantation in Controlled Donation after Circulatory-Determination-of-Death Using Normothermic Abdominal Perfusion

The main limitation to increased rates of lung transplantation (LT) continues to be the availability of suitable donors. At present, the largest source of lung allografts is still donation after the neurologic determination of death (brain-death donors, DBD). However, only 20% of these donors provide acceptable lung allografts for transplantation. One of the proposed strategies to increase the lung donor pool is the use of donors after circulatory-determination-of-death (DCD), which has the potential to significantly alleviate the shortage of transplantable lungs. According to the Maastricht classification, there are five types of DCD donors. The first two categories are uncontrolled DCD donors (uDCD); the other three are controlled DCD donors (cDCD). Clinical experience with uncontrolled DCD donors is scarce and remains limited to small case series. Controlled DCD donation, meanwhile, is the most accepted type of DCD donation for lungs. Although the DCD donor pool has significantly increased, it is still underutilized worldwide. To achieve a high retrieval rate, experience with DCD donation, adequate management of the potential DCD donor at the intensive care unit (ICU), and expertise in combined organ procurement are critical. This review presents a concise update of lung donation after circulatory-determination-of-death and includes a step-by-step protocol of lung procurement using abdominal normothermic regional perfusion.

Advancing the Scientific Basis for Determining Death in Controlled Organ Donation After Circulatory Determination of Death

In controlled organ donation after circulatory determination of death (cDCDD), accurate and timely death determination is critical, yet knowledge gaps persist. Further research to improve the science of defining and determining death by circulatory criteria is therefore warranted. In a workshop sponsored by the National Heart, Lung, and Blood Institute, experts identified research opportunities pertaining to scientific, conceptual, and ethical understandings of DCDD and associated technologies. This article identifies a research strategy to inform the biomedical definition of death, the criteria for its determination, and circulatory death determination in cDCDD. Highlighting knowledge gaps, we propose that further research is needed to inform the observation period following cessation of circulation in pediatric and neonatal populations, the temporal relationship between the cessation of brain and circulatory function after the withdrawal of life-sustaining measures in all patient populations, and the minimal pulse pressures that sustain brain blood flow, perfusion, activity, and function. Additionally, accurate predictive tools to estimate time to asystole following the withdrawal of treatment and alternative monitoring modalities to establish the cessation of circulatory, brainstem, and brain function are needed. The physiologic and conceptual implications of postmortem interventions that resume circulation in cDCDD donors likewise demand attention to inform organ recovery practices. Finally, because jurisdictionally variable definitions of death and the criteria for its determination may impede collaborative research efforts, further work is required to achieve consensus on the physiologic and conceptual rationale for defining and determining death after circulatory arrest.

Donation after Brain Death and Circulatory Death in Turkey: Current Status

Tissue and organ transplantation is the best treatment option for end-stage organ failure. However, organ shortage still remains to be the greatest challenge facing the field of organ transplantation. Millions of people die and are buried with healthy organs, which could save the lives of many patients who continue to wait on transplant lists. Countries must aim to work towards a system of matching organs as much as possible with the deceased donation to meet the growing demand for organs. This action will not only result in the reduction of organ trafficking activities but shall also make an enormous difference to those patients awaiting transplants where living organ donors are not an option. Donation after circulator death (DCD) has gained much attention over the last decade as one of the accepted practices in order to expand the donor pool. DCD donation takes place after declaration of death using cardio-respiratory criteria in contrast to donation after brain death (DBD) where neurological criteria are used. Although DCD remains a focus of interest and contributes to donor numbers in many countries, it also poses many challenges medically, ethically and legally.

Pre-transplant kidney quality evaluation using photoacoustic imaging during normothermic machine perfusion

Due to the shortage of kidneys donated for transplantation, surgeons are forced to use the organs with an elevated risk of poor function or even failure. Although the existing methods for pre-transplant quality evaluation have been validated over decades in population cohort studies across the world, new methods are needed as long as delayed graft function or failure in a kidney transplant occurs. In this study, we explored the potential of utilizing photoacoustic (PA) imaging during normothermic machine perfusion (NMP) as a means of evaluating kidney quality. We closely monitored twenty-two porcine kidneys using 3D PA imaging during a two-hour NMP session. Based on biochemical analyses of perfusate and produced urine, the kidneys were categorized into 'non-functional' and 'functional' groups. Our primary focus was to quantify oxygenation (sO2) within the kidney cortical layer of depths 2 mm, 4 mm, and 6 mm using two-wavelength PA imaging. Next, receiver operating characteristic (ROC) analysis was performed to determine an optimal cortical layer depth and time point for the quantification of sO2 to discriminate between functional and non-functional organs. Finally, for each depth, we assessed the correlation between sO2 and creatinine clearance (CrCl), oxygen consumption (VO2), and renal blood flow (RBF). We found that hypoxia of the renal cortex is associated with poor renal function. In addition, the determination of sO2 within the 2 mm depth of the renal cortex after 30 min of NMP effectively distinguishes between functional and non-functional kidneys. The non-functional kidneys can be detected with the sensitivity and specificity of 80% and 85% respectively, using the cut-off point of sO2 < 39%. Oxygenation significantly correlates with RBF and VO2 in all kidneys. In functional kidneys, sO2 correlated with CrCl, which is not the case for non-functional kidneys. We conclude that the presented technique has a high potential for supporting organ selection for kidney transplantation.

The circulatory death that saves lives-Intensive care nurses' conceptions of participating during 'donation after circulatory death': A phenomenographic study

AIM

To describe intensive care nurses' conceptions of participating during the donation after circulatory death (DCD) process in intensive care units in Sweden.

DESIGN

A qualitative design with a phenomenographic approach.

METHODS

In total, 12 semi-structured interviews were conducted in April 2022 with intensive care nurses from three hospitals. Data were analysed using a phenomenographic approach.

RESULTS

Conceptions of participating during the DCD process varied. Four main themes emerged: DCD as a system; Intensive care nurses' role in the situation; Life to death to life; The essence of DCD. Variations emerged regarding what the informants talked about and how they talked about the what. Variations were based on informants' perspective of their role in relation to the structure and the team, and their conceptions of care for patients and their relatives.

CONCLUSION

The findings illustrated success factors and challenges. Knowledge, experience, distinct structure, and relationship with relatives, among other factors, were described as success factors, while a lack of experience, difficulty in prognosing death, and organisational obstacles emerged as challenges. Furthermore, the findings showed that intensive care nurses play an important role in optimising the outcome of the DCD process. Their work related to DCD was conceived as being meaningful to fulfil more peoples' wishes to donate organs.

IMPACT

People on the waiting list for organ transplantation are dying due to a shortage of organs. The implementation of DCD, as a complement to Donation after Brain Death (DBD), contributed to an increase in the number of organ donors, and intensive care nurses play an important role during the DCD process. Previous research manifests the complexity concerning their role. There is a lack of nursing research regarding intensive care nurses' conceptions of what it means to participate in the DCD process, which emphasises the significance of this study.

REPORTING METHOD

This study is reported using consolidated criteria for reporting qualitative research (SRQR).

PATIENT OR PUBLIC CONTRIBUTION

No patient or public contribution.

Arteriolar hyalinization at 0-hour biopsy predicts long-term graft function in deceased kidney transplantation

OBJECTIVES

Regarding the relationship between donor kidney quality and renal graft function after deceased kidney transplantation (KTx) following donation after cardiac death (DCD), the evaluation timing varies depending on the study. Evaluation of histology and changes in long-term renal graft function is limited.

METHODS

A retrospective single-center study included 71 recipients who underwent 0-hour biopsy for KTx from DCD. The recipients were divided into two groups to evaluate factors related to renal graft function (study1). The two groups were categorized as stable graft function and poor graft function with the change of estimated glomerular filtration rate (eGFR) after KTx. The recipients were then divided into four groups to assess whether the factors identified in study1 were related to the change in long-term renal graft function (study2). They were categorized as follows: Improved, Stable, Deteriorated, and Primary non-function with the change of eGFR after KTx.

RESULTS

In study1, donor age ≥ 50 years (29.5% vs. 65.2%; p = 0.09), banff arteriolar hyalinosis (ah) score (0.66 ± 0.78 vs. 1.2 ± 1.0; p = 0.018), and presence of glomerulosclerosis (43.2% vs. 76.2%; p = 0.017) were significant risk factors for poor long-term graft function. When the recipients were divided into four groups, the severity of ah correlated well with changes in long-term renal function.

CONCLUSIONS

We can predict the shift in long-term renal graft function after KTx from DCD according to the severity of ah by 0-hour biopsy.

Using extracorporeal membrane oxygenation in donations after cardiac death or brain death: A single-center experience and long-term outcome

Aims

The use of extended criteria donors is a routine practice that sometimes involves extracorporeal membrane oxygenation (ECMO) in donations after cardiac death or brain death.

Methods

We performed a retrospective study in a single center from January 2006 to December 2019. The study included 90 deceased donor liver transplants. The patients were divided into three groups: the donation after brain death (DBD) group (n = 58, 64.4%), the DBD with ECMO group (n = 11, 12.2%) and the donation after cardiac death (DCD) with ECMO group (n = 21, 23.3%).

Results

There were no significant differences between the DBD with ECMO group and the DBD group. When comparing the DCD with ECMO group and the DBD group, there were statistically significant differences for total warm ischemia time (p < 0.001), total cold ischemia time (p = 0.023), and split liver transplantation (p < 0.001), and there was significantly poor recovery in regard to total bilirubin level (p = 0.027) for the DCD with ECMO group by repeated measures ANOVA. The 5-year survival rates of the DBD, DBD with ECMO, and DCD with ECMO groups were 78.1%, 90.9%, and 75.6%, respectively. The survival rate was not significantly different when comparing the DBD group to either the DBD with ECMO group (p = 0.435) or the DCD with ECMO group (p = 0.310).

Conclusions

Using ECMO in donations after cardiac death or brain death is a good technology, and it contributed to 35.6% of the liver graft pool.

Global legislation regulating the donation, procurement and distribution processes of organs and tissues from deceased donors for transplants: A scoping review

Introduction

Organ transplantation is one of the most successful advances in modern medicine. However, a legal system is necessary for its practice to be free from ethical flaws and to respect donors, recipients, and family members.

Objective

To map the global legislation regulating the donation, capture and distribution processes of organs and tissues from deceased donors for transplants.

Method

A scoping review according to the Joanna Briggs Institute was conducted in the following databases: Medline, CINAHL, Virtual Health Library, SCOPUS, Web of Science, Science Direct, and EMBASE, as well as gray literature, and reported according to the PRISMA extension for scoping reviews.

Results

We identified 3302 records, of which 77 were analyzed which enabled mapping the type of consent adopted and the existence of current legislation for harvesting organs and tissues after circulatory and brain death.

Conclusion

Opt-out consent predominates in Europe, and there is harvesting after brain and circulatory death. Opt-out predominates in the Americas, while Opt-in and harvesting of organs and tissues after brain death predominate in Asia and Oceania. The procurement of organs and tissues from deceased donors is practically non-existent in Africa.

Maintaining the permanence principle of death during normothermic regional perfusion in controlled donation after the circulatory determination of death: Results of a prospective clinical study

One concern about the use of normothermic regional perfusion (NRP) in controlled donation after the circulatory determination of death (cDCD) is that the brain may be perfused. We aimed to demonstrate that certain technical maneuvers preclude such brain perfusion. A nonrandomized trial was performed on cDCD donors. In abdominal normothermic regional perfusion (A-NRP), the thoracic aorta was blocked with an intra-aortic occlusion balloon. In thoracoabdominal normothermic regional perfusion (TA-NRP), the arch vessels were clamped and the cephalad ends vented to the atmosphere. The mean intracranial arterial blood pressure (ICBP) was invasively measured at the circle of Willis. Ten cDCD donors subject to A-NRP or TA-NRP were included. Mean ICBP and mean blood pressure at the thoracic and the abdominal aorta during the circulatory arrest were 17 (standard deviation [SD], 3), 17 (SD, 3), and 18 (SD, 4) mmHg, respectively. When A-NRP started, pressure at the abdominal aorta increased to 50 (SD, 13) mmHg, while the ICBP remained unchanged. When TA-NRP was initiated, thoracic aorta pressure increased to 71 (SD, 18) mmHg, but the ICBP remained unmodified. Recorded values of ICBP during NRP were 10 mmHg. In conclusion, appropriate technical measures applied during NRP preclude perfusion of the brain in cDCD. This study might help to expand NRP and increase the number of organs available for transplantation.

Development and outcomes of surgical and urological kidney transplantation programs in Germany: a total population analysis from 2006 to 2021

PURPOSE

Kidney transplantation (KT) is the most frequently performed organ transplantation. In Germany, KT is performed in urology and surgery departments with unknown consequences of this parallel structure. The aim of the study was to compare the development and outcome of KT in urology and surgery departments.

METHODS

On an institutional level, we analyzed the annual caseload from 2006 to 2021 with the reimbursement. INFO tool based on hospitals' quality reports (Reimbursement Institute, Hürth, Germany). For outcome comparison we extracted raw data from the transplantation centers' quality reports (Deutsche Stiftung Organtransplantation, DSO).

RESULTS

A total of 23,599 cases (17,781 deceased donor and 5,818 living donor KTs) were included. The total number of KTs decreased from 1851 in 2006 to 1701 in 2021 (- 8%; p = 0.12). The total number of urological KTs decreased from 592 cases in 2006 to 395 cases in 2021 (- 33.3%; p = 0.01). Further analysis revealed no significant differences between intra- and postoperative complications and graft quality at one year for deceased donor KTs (DDKT) although differences in immediate renal function and graft quality at discharge could be observed. There were no significant differences in immediate renal function and graft quality at discharge for living donor KTs (LDKT) between the specialties.

CONCLUSION

KTs performed in urology departments declined between 2006 and 2021. Nevertheless, intra- and postoperative complications as well as long-term function did not differ between surgical and urological KT programs. Hence, an interdisciplinary approach, especially considering the upcoming challenges in KT as, e.g., robot-assisted surgery seems reasonable.

Deceased donor kidney transplant policies in Asia - implications on practice and recommendations for the future

Deceased donor kidney transplantation (DDKT) is common in high income Western countries with high transplantation rates. However, the utilization of deceased organs is suboptimal in Asia, due to a multitude of factors. Coherent policies are integral to the development of DDKT programs and deterrence of commercialization, but most are still at an infancy and formative stage in Asia. This review article identifies the glass ceiling effects of social, cultural, religious, political, and technical factors hampering the progress of DDKT in Asia. Additionally, it reviews the history of policy development in different countries and describes their idiosyncratic barriers and challenges. Lastly, it discusses innovative policy measures that can be undertaken to proliferate DDKT practice and curtail commercialization. The long-term ideal is to achieve regional equity and self-sufficiency, through a shared ethos of social and ethical responsibility that transcends and resonates with the different segments of the Asian community.

Trends in kidney transplantation and living donor nephrectomy in Germany: a total population analysis from 2006 to 2021

PURPOSE

To analyze recent trends of surgical access routes, length of hospital stay (LOS), and mortality in kidney transplantation (KT) and living donor nephrectomy (LDN) in Germany.

MATERIALS AND METHODS

We studied the nationwide German hospital billing database and the German hospital quality reports from 2006 to 2021.

RESULTS

There were a total of 35.898 KTs. In total, 9044 (25%) were living donor transplantations, while 26.854 (75%) were transplantations after donation after brain death (DBD). The share of open LDN decreased from 82% in 2006 to 22% in 2020 (- 4%/year; p < 0.001). The share of laparoscopic LDN increased from 18% in 2006 to 70% in 2020 (+ 3%/year; p < 0.001). The share of robotic LDN increased from 0% in 2006 to 8% in 2020 (+ 0.6%/year; p < 0.001). Robotic-assisted KT increased from 5 cases in 2016 to 13 procedures in 2019 (p = 0.2). LOS was shorter after living donor KT, i.e., 18 ± 12.1 days versus 21 ± 19.6 days for DBD renal transplantation (p < 0.001). Moreover, LOS differed for open versus laparoscopic versus robotic LDN (9 ± 3.1 vs. 8 ± 2.9 vs. 6 ± 2.6; p = 0.031). The overall in-hospital mortality was 0.16% (n = 5) after LDN, 0.47% (n = 42) after living donor KT and 1.8% (n = 475) after DBD KT.

CONCLUSIONS

There is an increasing trend toward minimal-invasive LDN in recent years. Overall, in-hospital mortality was low after KT. However, 5 deceased healthy donors after LKD caution that the risks of this procedure should also be taken very seriously.

Effects of ketone body 3-hydroxybutyrate on cardiac and mitochondrial function during donation after circulatory death heart transplantation

Normothermic regional perfusion (NRP) allows assessment of therapeutic interventions prior to donation after circulatory death transplantation. Sodium-3-hydroxybutyrate (3-OHB) increases cardiac output in heart failure patients and diminishes ischemia-reperfusion injury, presumably by improving mitochondrial metabolism. We investigated effects of 3-OHB on cardiac and mitochondrial function in transplanted hearts and in cardiac organoids. Donor pigs (n = 14) underwent circulatory death followed by NRP. Following static cold storage, hearts were transplanted into recipient pigs. 3-OHB or Ringer's acetate infusions were initiated during NRP and after transplantation. We evaluated hemodynamics and mitochondrial function. 3-OHB mediated effects on contractility, relaxation, calcium, and conduction were tested in cardiac organoids from human pluripotent stem cells. Following NRP, 3-OHB increased cardiac output (P < 0.0001) by increasing stroke volume (P = 0.006), dP/dt (P = 0.02) and reducing arterial elastance (P = 0.02). Following transplantation, infusion of 3-OHB maintained mitochondrial respiration (P = 0.009) but caused inotropy-resistant vasoplegia that prevented weaning. In cardiac organoids, 3-OHB increased contraction amplitude (P = 0.002) and shortened contraction duration (P = 0.013) without affecting calcium handling or conduction velocity. 3-OHB had beneficial cardiac effects and may have a potential to secure cardiac function during heart transplantation. Further studies are needed to optimize administration practice in donors and recipients and to validate the effect on mitochondrial function.

Organ storage in renal transplantation

PURPOSE OF REVIEW

Kidney transplantation is vital for those with end-stage renal disease, enhancing quality of life and longevity. It is the preferred treatment but is hindered by a global disparity between donor kidney availability and demand. Therefore, optimizing organ storage techniques is crucial to mitigate the effects of ischemia reperfusion injury in available organs. Recent interest has centered on innovative methods like oxygenated normothermic perfusion and abdominal regional perfusion.

RECENT FINDINGS

Multiple recent metanalyses, including a Cochrane review, confirm the benefits of hypothermic machine perfusion (HMP) for deceased donor kidneys, demonstrating its utility and cost effectiveness. The benefits of oxygenated normothermic perfusion have been seen in retrospective data sets but not in prospective trials. Abdominal regional perfusion (aNRP) is gaining interest, especially for liver transplantation, but kidney specific data are scant.

SUMMARY

High-quality evidence backs the use of HMP for deceased donor kidneys. Despite interest in other techniques, clinical evidence for their benefits in kidney transplantation is lacking. The gap between innovation and verified success emphasizes the need for continued research and collaboration between medical professionals, researchers, and ethical committees. This review aims to further illuminate the complexities and advancements in the field, bridging the knowledge gap and aiding in the continual pursuit of excellence in transplantation.

Liver transplantation with uncontrolled versus controlled DCD donors using normothermic regional perfusion and ex-situ machine perfusion

In Italy, 20 minutes of continuous, flat-line electrocardiogram are required for death declaration, which significantly increases the risks of donation after circulatory death (DCD) LT. Despite prolonged warm ischemia time, Italian centers reported good outcomes in controlled donation after circulatory death LT by combining normothermic regional and end-ischemic machine perfusion. However, data on uncontrolled DCD (uDCD) LT performed by this approach are lacking. This was a multicenter, retrospective study performed at 3 large-volume centers comparing clinical outcomes of uncontrolled versus controlled DCD LT. The aim of the study was to assess outcomes of sequential normothermic regional perfusion and end-ischemic machine perfusion in uncontrolled DCD liver transplantation (LT). Of 153 DCD donors evaluated during the study period, 40 uDCD and 59 donation after circulatory death grafts were transplanted (utilization rate 52% vs. 78%, p = 0.004). Recipients of uDCD grafts had higher MEAF (4.9 vs. 3.5, p < 0.001) and CCI scores at discharge (24.4 vs. 8.7, p = 0.026), longer ICU stay (5 vs. 4 d, p = 0.047), and a trend toward more severe AKI. At multivariate analysis, 90-day graft loss was associated with recipient BMI and lactate downtrend during normothermic regional perfusion. One-year graft survival was lower in uDCD (75% vs. 90%, p = 0.007) but became comparable when non-liver-related graft losses were treated as censors (77% vs. 90%, p = 0.100). The incidence of ischemic cholangiopathy was 10% in uDCD versus 3% in donation after circulatory death, p = 0.356. uDCD LT with prolonged warm ischemia is feasible by the sequential use of normothermic regional perfusion and end-ischemic machine perfusion. Proper donor and recipient selection are key to achieving good outcomes in this setting.

EISOR Delivery: Regional experience with sharing equipe, equipment & expertise to increase cDCD donor pool in time of pandemic

Donation after circulatory death (DCD) programs are expanding in Europe, in the attempt to expand donors pool. Even in controlled DCD donors, however, a protracted warm ischemia time occurring in the perimortem period might damage organs, making these unsuitable for transplantation. Implementing a strategy of extracorporeal interval support for organ retrieval (EISOR), a regional reperfusion with normothermic, oxygenated blood provides a physiologic environment allowing extensive assessment of potential grafts, and potentially promotes recovery of native function. Here we report the results of a multi-center retrospective cohort study including 29 Maastricht Category III controlled DCD donors undergoing extracorporeal support in a regional DCD/EISOR Training Center, and in the network of referring In-Training Centers, under the liaison of the regional Transplant Coordination Center during COVID-19 pandemic, between March 2020 and November 2021. The study aims to understand whether a mobile, experienced EISOR team implementing a consistent technique and sharing its equipe, expertise and equipment in a regional network of hospitals, might be effective and efficient in implementing the regional DCD program activity even in a highly stressed healthcare system.

Extended criteria liver donation after circulatory death with prolonged warm ischemia: a pilot experience of normothermic regional perfusion and no subsequent ex-situ machine perfusion

BACKGROUND

Livers from controlled donation after circulatory death (cDCD) with very prolonged warm ischemic time (WIT) are regularly transplanted after abdominal normothermic regional perfusion (aNRP) plus ex-situ machine perfusion (MP). Considering aNRP as in-situ MP, we investigated whether the results of a pilot experience of extended criteria cDCD liver transplantation (LT) with prolonged WIT, with aNRP alone, were comparable to the best possible outcomes in low-risk cDCD LT.

METHODS

Prospectively collected data on 24 cDCD LT, with aNRP alone, were analyzed.

RESULTS

The median total and asystolic WIT were 51 and 25 min. Measures within benchmark cut-offs were: median duration of surgery (5.9 h); median intraoperative transfusions (3 units of red blood cells); need for renal replacement therapy (2/24 patients); median intensive care stay (3 days); key complications; overall morbidity, graft loss, and retransplantation up to 12 months; 12-month mortality (2/21 patients). The median hospital stay (33 days, due to logistics) and mortality up to 6 months (2/24 patients, due to graft-unrelated causes) exceeded benchmark thresholds.

CONCLUSIONS

This pilot experience suggests that livers from cDCD with very prolonged WIT that appear viable during adequate quality aNRP may be safely transplanted, with no need for ex-situ MP, with considerable resource savings.

Outcomes of liver transplantation with thoracoabdominal normothermic regional perfusion: a matched-controlled initial experience in Spain

Thoracoabdominal (TA) normothermic regional perfusion (NRP) should allow the safe recovery of heart and liver grafts simultaneously in the context of controlled donation after circulatory death (cDCD). We present the initial results of cDCD liver transplantation with simultaneous liver and heart procurement in Spain until October 2021. Outcomes were compared with a matched cohort of cDCD with abdominal NRP (A-NRP) from participating institutions. Primary endpoints comprised early allograft dysfunction (EAD) or primary non-function (PNF), and the development of ischemic-type biliary lesions (ITBL). Six transplants were performed using cDCD with TA-NRP during the study period. Donors were significantly younger in the TA-NRP group than in the A-NRP group (median 45.6 years and 62.9 years respectively, p = 0.011), with a median functional warm ischemia time of 12.5 min in the study group and 13 min in the control group. Patient characteristics, procurement times, and surgical baseline characteristics did not differ significantly between groups. No patient in the study group developed EAD or PNF, and over a median follow-up of 9.8 months, none developed ITBL or graft loss. Extending A-NRP to TA-NRP for cardiac procurement may be technically challenging, but it is both feasible and safe, showing comparable postoperative outcomes to A-NRP.

Bronchial Stenosis After Lung Transplantation From cDCD Donors Using Simultaneous Abdominal Normothermic Regional Perfusion: A Single-center Experience

BACKGROUND

Controlled donation after circulatory death (cDCD) has increased the number of lung donors significantly. The use of abdominal normothermic regional perfusion (A-NRP) during organ procurement is a common practice in some centers due to its benefits on abdominal grafts. This study aimed to assess whether the use of A-NRP in cDCD increases the frequency of bronchial stenosis in lung transplant (LT) recipients.

METHODS

A single-center, retrospective study including all LTs was performed between January 1, 2015, and August 30, 2022. Airway stenosis was defined as a stricture that leads to clinical/functional worsening requiring the use of invasive monitoring and therapeutic procedures.

RESULTS

A total of 308 LT recipients were included in the study. Seventy-six LT recipients (24.7%) received lungs from cDCD donors using A-NRP during organ procurement. Forty-seven LT recipients (15.3%) developed airway stenosis, with no differences between lung recipients with grafts from cDCD (17.2%) and donation after brain death donors (13.3%; P  = 0.278). A total of 48.9% of recipients showed signs of acute airway ischemia on control bronchoscopy at 2 to 3 wk posttransplant. Acute ischemia was an independent risk factor for airway stenosis development (odds ratio = 2.523 [1.311-4.855], P  = 0.006). The median number of bronchoscopies per patient was 5 (2-9), and 25% of patients needed >8 dilatations. Twenty-three patients underwent endobronchial stenting (50.0%) and each patient needed a median of 1 (1-2) stent.

CONCLUSIONS

Incidence of airway stenosis is not increased in LT recipients with grafts obtained from cDCD donors using A-NRP.

Real-time laser speckle contrast imaging measurement during normothermic machine perfusion in pretransplant kidney assessment

OBJECTIVES

Normothermic machine perfusion (NMP) provides a platform for pre-transplant kidney quality assessment that is essential for the use of marginal donor kidneys. Laser speckle contrast imaging (LSCI) presents distinct advantages as a real-time and noncontact imaging technique for measuring microcirculation. In this study, we aimed to assess the value of LSCI in visualizing renal cortical perfusion and investigate the additional value of dual-side LSCI measurements compared to single aspect measurement during NMP.

METHODS

Porcine kidneys were obtained from a slaughterhouse and then underwent NMP. LSCI was used to measure one-sided cortical perfusion in the first 100 min of NMP. Thereafter, the inferior renal artery branch was occluded to induce partial ischemia and LSCI measurements on both ventral and dorsal sides were performed.

RESULTS

LSCI fluxes correlated linearly with the renal blood flow (R2  = 0.90, p < 0.001). After renal artery branch occlusion, absence of renal cortical perfusion could be visualized and semiquantified by LSCI. The overall ischemic area percentage of the ventral and dorsal sides was comparable (median interquartile range [IQR], 38 [24-43]% vs. 29 [17-46]%, p = 0.43), but heterogenous patterns between the two aspects were observed. There was a significant difference in oxygen consumption (mean ± standard deviation [SD], 2.57 ± 0.63 vs. 1.83 ± 0.49 mLO2 /min/100 g, p < 0.001), urine output (median [IQR], 1.3 [1.1-1.7] vs. 0.8 [0.6-1.3] mL/min, p < 0.05), lactate dehydrogenase (mean ± SD, 768 ± 370 vs. 905 ± 401 U/L, p < 0.05) and AST (mean ± SD, 352 ± 285 vs. 462 ± 383 U/L, p < 0.01) before and after renal artery occlusion, while no significant difference was found in creatinine clearance, fractional excretion of sodium, total sodium reabsorption and histological damage.

CONCLUSIONS

LSCI fluxes correlated linearly with renal blood flow during NMP. Renal cortical microcirculation and absent perfusion can be visualized and semiquantified by LSCI. It provides a relative understanding of perfusion levels, allowing for a qualitative comparison between regions in the kidney. Dual-side LSCI measurements are of added value compared to single aspect measurement and renal function markers.

Stem cell Derived Extracellular Vesicles to Alleviate ischemia-reperfusion Injury of Transplantable Organs. A Systematic Review

BACKGROUND

The possible beneficial effects of stem cell-derived EV on ischemia-reperfusion injury (IRI) in organ transplantation have been frequently investigated; however, the source of EV, as well as the methods of isolation and administration vary widely. We conducted a systematic review to summarize current pre-clinical evidence on stem cell-derived EV therapy for IRI of transplantable organs.

METHODS

PubMed, Embase and Web of Science were searched from inception until August 19th, 2022, for studies on stem cell-derived EV therapy for IRI after heart, kidney, liver, pancreas, lung and intestine transplantation. The Systematic Review Center for Laboratory animal Experiments (SYRCLE) guidelines were followed to assess potential risk of bias.

RESULTS

The search yielded 4153 unique articles, of which 96 were retained. We identified 32 studies on cardiac IRI, 38 studies on renal IRI, 21 studies on liver IRI, four studies on lung IRI and one study on intestinal IRI. Most studies used rodent models of transient ischemic injury followed by in situ reperfusion. In all studies, EV therapy was associated with improved outcome albeit to a variable degree. EV-therapy reduced organ injury and improved function while displaying anti-inflammatory-, immunomodulatory- and pro-regenerative properties.

CONCLUSION

A multitude of animal studies support the potential of stem cell-derived EV-therapy to alleviate IRI after solid organ transplantation but suffer from low reporting quality and wide methodological variability. Future studies should focus on determining optimal stem cell source, dosage, and timing of treatment, as well as long-term efficacy in transplant models.

Beneficial Effects of Combined Use of Extracorporeal Membrane Oxygenation and Hypothermic Machine Perfusion in Porcine Donors after Cardiac Death for Liver Transplantation

Grafts from donors after cardiac death (DCD) have greatly contributed to expanding the donor organ pool. This study aimed to determine the benefits of subnormothermic extracorporeal membrane oxygenation (ECMO) and hypothermic machine perfusion (HMP) in a porcine model of DCD liver. Female domestic crossbred Large Yorkshire and Landrace pigs weighing approximately 20 kg were used. The abdominal aorta and inferior vena cava were cannulated and connected to an ECMO circuit for in situ perfusion of the abdominal organs at 22 °C for 60 min, 45 min after cardiac death. The pigs were divided into the cold storage (CS) group (n = 3), where liver grafts were preserved at 4 °C, and the HMP group (n = 3), where liver grafts were preserved by HMP at 8-10 °C. After 4 h of preservation, liver function was evaluated using an isolated liver reperfusion model for 2 h. Although the difference was insignificant, the liver effluent enzyme levels in the HMP group were lower than those in the CS group. Furthermore, morphological findings showed fewer injured hepatocytes in the HMP group than in the CS group. The combined use of in situ subnormothermic ECMO and HMP was beneficial for the functional improvement of DCD liver grafts.

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.

Healthcare System Impact on Deceased Organ Donation and Transplantation: A Comparison Between the Top 10 Organ Donor Countries With 4 Countries in Southeast Asia

The need for organ donation is constantly increasing. Some countries have made improvements, while others, such as countries in Southeast Asia (SEA), have some of the lowest rates of deceased donors (pmp). This review aims to compare 14 countries with regards to many variables related to healthcare systems. Countries leading in deceased organ donation spend more on health and education, which is associated with increased potential for deceased organ donation. Out-of-pocket expenditure, is also associated with a decrease in deceased organ donation. Countries in SEA are lacking in healthcare resources such as workforce and materials, which are both necessary for a successful transplant program. Most countries in SEA have an excellent foundation for successful organ donation systems, including proper legislation, government support, and brain death laws along with an overall acceptance of brain death diagnosis. Priorities should include improving coordination, donor identification, and healthcare worker education. Countries in SEA have a lot of potential to increase deceased organ donation, especially by investing in healthcare and education. There is no one size fits all for organ donation programs and countries in SEA should focus on their strengths and take cultural differences into consideration when planning interventions.

Multiorgan recovery in a cadaver body using mild hypothermic ECMO treatment in a murine model

BACKGROUND

Transplant candidates on the waiting list are increasingly challenged by the lack of organs. Most of the organs can only be kept viable within very limited timeframes (e.g., mere 4-6 h for heart and lungs exposed to refrigeration temperatures ex vivo). Donation after circulatory death (DCD) using extracorporeal membrane oxygenation (ECMO) can significantly enlarge the donor pool, organ yield per donor, and shelf life. Nevertheless, clinical attempts to recover organs for transplantation after uncontrolled DCD are extremely complex and hardly reproducible. Therefore, as a preliminary strategy to fulfill this task, experimental protocols using feasible animal models are highly warranted. The primary aim of the study was to develop a model of ECMO-based cadaver organ recovery in mice. Our model mimics uncontrolled organ donation after an "out-of-hospital" sudden unexpected death with subsequent "in-hospital" cadaver management post-mortem. The secondary aim was to assess blood gas parameters, cardiac activity as well as overall organ state. The study protocol included post-mortem heparin-streptokinase administration 10 min after confirmed death induced by cervical dislocation under full anesthesia. After cannulation, veno-arterial ECMO (V-A ECMO) was started 1 h after death and continued for 2 h under mild hypothermic conditions followed by organ harvest. Pressure- and flow-controlled oxygenated blood-based reperfusion of a cadaver body was accompanied by blood gas analysis (BGA), electrocardiography, and histological evaluation of ischemia-reperfusion injury. For the first time, we designed and implemented, a not yet reported, miniaturized murine hemodialysis circuit for the treatment of severe hyperkalemia and metabolic acidosis post-mortem.

RESULTS

BGA parameters confirmed profound ischemia typical for cadavers and incompatible with normal physiology, including extremely low blood pH, profound negative base excess, and enormously high levels of lactate. Two hours after ECMO implantation, blood pH values of a cadaver body restored from < 6.5 to 7.3 ± 0.05, pCO2 was lowered from > 130 to 41.7 ± 10.5 mmHg, sO2, base excess, and HCO3 were all elevated from below detection thresholds to 99.5 ± 0.6%, - 4 ± 6.2 and 22.0 ± 6.0 mmol/L, respectively (Student T test, p < 0.05). A substantial decrease in hyperlactatemia (from > 20 to 10.5 ± 1.7 mmol/L) and hyperkalemia (from > 9 to 6.9 ± 1.0 mmol/L) was observed when hemodialysis was implemented. On balance, the first signs of regained heart activity appeared on average 10 min after ECMO initiation without cardioplegia or any inotropic and vasopressor support. This was followed by restoration of myocardial contractility with a heart rate of up to 200 beats per minute (bpm) as detected by an electrocardiogram (ECG). Histological examinations revealed no evidence of heart injury 3 h post-mortem, whereas shock-specific morphological changes relevant to acute death and consequent cardiac/circulatory arrest were observed in the lungs, liver, and kidney of both control and ECMO-treated cadaver mice.

CONCLUSIONS

Thus, our model represents a promising approach to facilitate studying perspectives of cadaveric multiorgan recovery for transplantation. Moreover, it opens new possibilities for cadaver organ treatment to extend and potentiate donation and, hence, contribute to solving the organ shortage dilemma.

Evaluation of functional warm ischemia time during controlled donation after circulatory determination of death using normothermic regional perfusion (ECMO-TT): A prospective multicenter cohort study

BACKGROUND

Controlled donation after circulatory determination of death (cDCD) seems an effective way to mitigate the critical shortage of available organs for transplant worldwide. As a recently developed procedure for organ retrieval, some questions remain unsolved such as the uncertainty regarding the effect of functional warm ischemia time (FWIT) on organs´ viability.

METHODS

We developed a multicenter prospective cohort study collecting all data from evaluated organs during cDCD from 2017 to 2020. All the procedures related to cDCD were performed with normothermic regional perfusion. The analysis included organ retrieval as endpoint and FWIT as exposure of interest. The effect of FWIT on the likelihood for organ retrieval was evaluated with Relative distribution analysis.

RESULTS

A total amount of 507 organs´ related information was analyzed from 95 organ donors. Median donor age was 62 years, and 63% of donors were male. Stroke was the most common diagnosis before withdrawal of life-sustaining therapy (61%), followed by anoxic encephalopathy (21%). This analysis showed that length of FWIT was inversely associated with organ retrieval rates for liver, kidneys, and pancreas. No statistically significant association was found for lungs.

CONCLUSIONS

Results showed an inverse association between functional warm ischemia time (FWIT) and retrieval rate. We also have postulated optimal FWIT's thresholds for organ retrieval. FWIT for liver retrieval remained between 6 and less than 11 min and in case of kidneys and pancreas, the optimal FWIT for retrieval was 6 to 12 min. These results could be valuable to improve organ utilization and for future analysis.

Dilemmas concerning heart procurement in controlled donation after circulatory death

With an expanding population at risk for heart failure and the resulting increase in patients admitted to the waiting list for heart transplantation, the demand of viable organs exceeds the supply of suitable donor hearts. Use of hearts after circulatory death has reduced this deficit. Two primary techniques for heart procurement in circulatory death donors have been described: direct procurement and perfusion and thoraco-abdominal normothermic regional perfusion. While the former has been accepted as an option for heart procurement in circulatory death donors, the latter technique has raised some ethical questions in relation to the dead donor rule. In this paper we discuss the current dilemmas regarding these heart procurement protocols in circulatory death donors.