Improving the Outcomes of Organs Obtained From Controlled Donation After Circulatory Death Donors Using Abdominal Normothermic Regional Perfusion

A 5-year single-center early experience of heart transplantation from donation after circulatory-determined death donors

BACKGROUND

In an effort to address the increasing demand for heart transplantation within the United Kingdom (UK), we established a clinical program of heart transplantation from donation after circulatory-determined death (DCD) donors in 2015. After 5 years, we report the clinical early outcomes and impact of the program.

METHODS

This is a single-center, retrospective, matched, observational cohort study comparing outcomes of hearts transplanted from DCD donors from March 1, 2015 to February 29, 2020 with those from matched donation after brain death (DBD) donors at Royal Papworth Hospital (RPH) (Cambridge, UK). DCD hearts were either retrieved using thoracoabdominal normothermic regional perfusion or the direct procurement and perfusion technique. All DBD hearts were procured using standard cold static storage. The primary outcomes were recipient 30-day and 1-year survival.

RESULTS

During the 5-year study, DCD heart donation increased overall heart transplant activity by 48% (79 for DCD and 164 for DBD). There was no difference in survival at 30 days (97% for DCD vs 99% for DBD, p = 1.00) or 1 year (91% for DCD vs 89% for DBD, p = 0.72). There was no difference in the length of stay in the intensive care unit (7 for DCD vs 6 for DBD days, p = 0.24) or in the hospital (24 for DCD vs 25 for DBD days, p = 0.84).

CONCLUSIONS

DCD heart donation increased overall heart transplant activity at RPH by 48%, with no difference in 30-day or 1-year survival in comparison with conventional DBD heart transplantations. DCD heart donation is set to make a dramatic difference in the number of patients who can benefit from heart transplantation.

Machine Perfusions in Liver Transplantation: The Evidence-Based Position Paper of the Italian Society of Organ and Tissue Transplantation

The use of machine perfusion (MP) in liver transplantation (LT) is spreading worldwide. However, its efficacy has not been demonstrated, and its proper clinical use has far to go to be widely implemented. The Società Italiana Trapianti d'Organo (SITO) promoted the development of an evidence-based position paper. A 3-step approach has been adopted to develop this position paper. First, SITO appointed a chair and a cochair who then assembled a working group with specific experience of MP in LT. The Guideline Development Group framed the clinical questions into a patient, intervention, control, and outcome (PICO) format, extracted and analyzed the available literature, ranked the quality of the evidence, and prepared and graded the recommendations. Recommendations were then discussed by all the members of the SITO and were voted on via the Delphi method by an institutional review board. Finally, they were evaluated and scored by a panel of external reviewers. All available literature was analyzed, and its quality was ranked. A total of 18 recommendations regarding the use and the efficacy of ex situ hypothermic and normothermic machine perfusion and sequential normothermic regional perfusion and ex situ MP were prepared and graded according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) method. A critical and scientific approach is required for the safe implementation of this new technology.

Maintaining the permanence principle for death during in situ normothermic regional perfusion for donation after circulatory death organ recovery: A United Kingdom and Canadian proposal

There is international variability in the determination of death. Death in donation after circulatory death (DCD) can be defined by the permanent cessation of brain circulation. Post-mortem interventions that restore brain perfusion should be prohibited as they invalidate the diagnosis of death. Retrieval teams should develop protocols that ensure the continued absence of brain perfusion during DCD organ recovery. In situ normothermic regional perfusion (NRP) or restarting the heart in the donor's body may interrupt the permanent cessation of brain perfusion because, theoretically, collateral circulations may restore it. We propose refinements to current protocols to monitor and exclude brain reperfusion during in situ NRP. In abdominal NRP, complete occlusion of the descending aorta prevents brain perfusion in most cases. Inserting a cannula in the ascending aorta identifies inadequate occlusion of the descending aorta or any collateral flow and diverts flow away from the brain. In thoracoabdominal NRP opening the aortic arch vessels to atmosphere allows collateral flow to be diverted away from the brain, maintaining the permanence standard for death and respecting the dead donor rule. We propose that these hypotheses are correct when using techniques that simultaneously occlude the descending aorta and open the aortic arch vessels to atmosphere.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Role of normothermic perfusión with ECMO in donation after controlled cardiac death in Spain

Spain has become one of the most active countries in donation after controlled cardiac death, using normothermic abdominal perfusion with ECMO in more than 50% of all donors - a situation contributed to by the creation of mobile teams to support hospitals lacking this technology. The donation process must be respectful of the wishes and values of the patients and their relatives, especially if there is pre mortem manipulation, and the absence of cerebral perfusion should be guaranteed. The liver is the most benefited organ by reducing biliary complications as well as the loss of grafts. In renal transplantation, the technique could contribute to reduce the incidence of delayed graft function. In addition, the procedure is compatible with surgical rapid recovery in hypothermia when there is also lung donation. The future lies in the consolidation of cardiac donation by extending normothermic perfusion to the thoracic cavity.

Donation after circulatory death liver transplantation: consensus statements from the Spanish Liver Transplantation Society

Livers from donation after circulatory death (DCD) donors are an increasingly more common source of organs for transplantation. While there are few high-level studies in the field of DCD liver transplantation, clinical practice has undergone progressive changes during the past decade, in particular due to mounting use of postmortem normothermic regional perfusion (NRP). In Spain, uncontrolled DCD has been performed since the late 1980s/early 1990s, while controlled DCD was implemented nationally in 2012. Since 2012, the rise in DCD liver transplant activity in Spain has been considerable, and the great majority of DCD livers transplanted in Spain today are recovered with NRP. A panel of the Spanish Liver Transplantation Society was convened in 2018 to evaluate current evidence and accumulated experience in DCD liver transplantation, in particular addressing issues related to DCD liver evaluation, acceptance criteria, and recovery as well as recipient selection and postoperative management. This panel has created a series of consensus statements for the standard of practice in Spain and has published these statements with the hope they might help guide other groups interested in implementing new forms of DCD liver transplantation and/or introducing NRP into their clinical practices.

Donation after circulatory death liver transplantation: What are the limits for an acceptable DCD graft?

The utilization of donation after circulatory death (DCD) livers has been growing over the last decade. In large-volume centers, survival outcomes have improved and are comparable to outcomes with brain death donor (DBD) liver transplantation (LT). The relatively concentrated success with DCD LT demonstrated by high-volume transplant centers has rekindled international enthusiasm. The combination of increasing expertise in DCD LT and ongoing shortage in transplantable organs has promoted expansion of the DCD donor pool with regards to donor age, body mass index and donor warm ischemia time. In this review, we focused on the practice patterns in DCD liver graft utilization in the last decade, along with the possibilities for further expansion of DCD liver graft utilization and new technologies, such as machine perfusion.

Does Normothermic Regional Perfusion Improve the Results of Donation After Circulatory Death Liver Transplantation?

BACKGROUND

The so-called grafts or donors with extended criteria are a risk factor for the development of liver transplant activity. One source comes from controlled donation after circulatory death (cDCD). The hypothesis was to verify the improvement in results by comparing DCD liver transplants performed with postmortem normothermic regional perfusion (NRP) vs super-rapid recovery (SRR), the current standard for cDCD. A prospective study comparing both techniques was carried out.

METHODS

A total of 42 transplants were performed with cDCD, 22 of which were with SRR and 23 with NRP from April 2014 to September 2019.

RESULTS

Differences were found in early allograft dysfunction (68.1% in the SRR group vs 25% in the NRP group; P < .01) and biliary complications (22.7% vs 5%, respectively; P = .04). Differences were also found, although not statistically significant, in ischemic cholangiopathy (13.6% in the SRR group vs 5% in the NRP group; P = .09), and retransplant rate (9.1% vs 0%, respectively; P = .3).

CONCLUSIONS

With the use of NRP machines, results are similar to the standard donation with donors in brain death in terms of rate of early allograft dysfunction and survival of the patient and graft attempted, reducing the rate of ischemic cholangiopathy compared with SRR.

Top Papers in Liver Transplantation 2017-2018

Organ shortage remains a major limitation in liver transplantation, and there has been a significant effort over the past decade to increase the existing deceased donor pool. Recent advances have included better selection and management of donors after circulatory arrest, application of hypothermic and normothermic perfusion, minimization of standard immunosuppression, and use of new immunosuppressive medications. Additionally, there has been renewed emphasis and understanding of liver immunology and the impact of antibody-mediated rejection. Together, these advances have allowed for expansion of the donor pool with concurrent improved patient outcomes. Furthermore, direct-acting antiviral agents for the treatment of hepatitis C virus infection has been management of this infection. These changes have affected the practice of solid organ transplantation by altering the framework by which patients with end-stage organ disease are managed and receive organ transplants. In this article, we analyze some of the top papers published in 2017-2018 dealing with these issues.

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

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

Combined lung and liver procurement in controlled donation after circulatory death using normothermic abdominal perfusion. Initial experience in two Spanish centers

Combining simultaneously lung and liver procurement in controlled donation after circulatory death (cDCD) using normothermic abdominal perfusion (NRP) for abdominal grafts and cooling and rapid recovery technique (RR) for the lungs increases the complexity of the procurement procedure and might injure the grafts. A total of 19 cDCDs from two centers using this combined procedure were evaluated, and 16 liver and 21 lung transplantations were performed. As controls, 34 donors after brain death (DBDs) were included (29 liver and 41 lung transplantations were performed). Two cDCD liver recipients developed primary nonfunction (12.5%). No cases of ischemic cholangiopathy were observed among cDCD recipients. The 1-year and 2-year liver recipients survival was 87.5% and 87.5% for the cDCD group, and 96% and 84.5% for the DBD group, respectively (P = .496). The 1-year and 2-year lung recipients survival was 84% and 84% for the cDCD group and 90% and 90% for the DBD group, respectively (P = .577). This is the largest experience ever reported in cDCD with the use of NRP combined with RR of the lungs. This combined method offers an outstanding recovery rate and liver and lung recipients survival comparable with those transplanted with DBDs. Further studies are needed to confirm our findings.

Favorable Outcomes After Liver Transplantation With Normothermic Regional Perfusion From Donors After Circulatory Death: A Single-center Experience

BACKGROUND

Controlled donation after circulatory death (cDCD) has been associated with a high incidence of ischemic cholangiopathy and other perioperative complications. In an attempt to avoid these complications, we implemented an active protocol of cDCD liver transplant (LT) with normothermic regional perfusion (NRP) preservation.

METHODS

This is a descriptive analysis of data collected from a prospective date base of cDCD LT preserved with NRP from January 2015 to June 2017 with a minimum follow up of 9 months.

RESULTS

Fifty-seven potential cDCD donors were connected to the NRP system. Of these, 46 livers were transplanted over a 30-month period (80% liver recovery rate). The median posttransplant peak in alanine transaminase was 1136 U/L (220-6683 U/L). Seven (15%) patients presented postreperfusion syndrome and 11 (23%) showed early allograft dysfunction. No cases of ischemic cholangiopathy were diagnosed, and no graft loss was observed over a medium follow-up period of 19 months. Of note, 13 donors were older than 65 years, achieving comparable perioperative and midterm results to younger donors.

CONCLUSIONS

As far as we know, this represents the largest published series of cDCD LT with NRP preservation. Our results demonstrate that cDCD liver grafts preserved with NRP appear far superior to those obtained by the conventional rapid recovery technique.

Combined Thorax-Abdomen Extraction in Controlled Cardiac Death (Maastricht Type III) Donors

Donation after circulatory death (DCD) or controlled cardiac death (Maastricht type III donors) is that in which the irreversible cessation of circulatory and respiratory function occurs after the withdrawal of life-sustaining therapies. The shortage of available donor lungs has prompted the development of programs of controlled DCD for lung transplantation. The combined thorax-abdomen extraction in these cases is carried out only in a few centers in Spain, being even more exceptional considering the combined use of super rapid lung extraction with abdominal normothermic regional perfusion. The success achieved with the first cases of combined thorax-abdomen extraction in Maastricht type III donors in Navarra shows that it is a feasible and safe procedure.

Interhospital Transfers of a Mobile Extracorporeal Membrane Oxygenation Team for Maastricht III Donations

OBJECTIVE

The objective is to describe the donations made with extracorporeal membrane oxygenation as a method of preservation to meet the characteristics of the donors and the transplants obtained.

METHODS

This was a retrospective descriptive study, using the donation registration data made at Virgen de las Nieves Hospital from 2010 to February 2018.

RESULTS

A total of 11 transfers occurred: 2 to the province of Jaen (Jaen Hospital, 92 km from Virgen de las Nieves Hospital; San Agustín Hospital, Linares, 136 km), 1 to Santa Ana Hospital, Motril (68 km), 1 to Poniente Hospital, El Ejido, Almeria (137 km), and 7 trips within the city of Granada. From these donations, a total of 21 kidneys, 3 livers, 10 corneal transplants, 4 extractions of osteotendinous tissue, and 1 extraction of vascular tissue were obtained.

CONCLUSION

Extracorporeal membrane oxygenation mobile teams can enable donation in controlled donation after circulatory death with normothermic preservation in hospitals without these resources, which increases the donor group and optimizes graft results.

In Situ Normothermic Regional Perfusion for Liver Donation From China Category III (Organ Donation After Brain Death Followed by Circulatory Death): A Single-Center Cohort Study

OBJECTIVES

Organ donation after brain death followed by circulatory death is practiced in China. This study evaluated the application of normothermic regional perfusion to protect the liver grafts from these donors from warm ischemia in a large transplant center in China.

MATERIALS AND METHODS

This prospective study involved 19 liver transplants from brain death followed by circulatory death donors that were conducted between December 2014 and June 2017. We evaluated the baseline characteristics of the donors and recipients and compared outcomes of both groups. Graft and recipient survival and postoperative complications were also analyzed.

RESULTS

Although the normothermic regional perfusion group consisted of marginal donors with prolonged warm ischemia and recipients with higher Model for End-Stage Liver Disease scores (P < .05), postoperative tests indicated no differences in liverfunction recovery in both groups. Furthermore, total bilirubin decreased significantly faster in the normothermic regional perfusion group than in the control group (P < .05). Both groups showed similar 1-year recipient survival rates. No recipients in the normothermic regional perfusion group had any biliary complications, whereas 2 recipients in the control group developed ischemic cholangiopathy and received invasive treatment during follow-up.

CONCLUSIONS

In situ normothermic regional perfusion demonstrated a significant benefit in grafts from brain death followed by circulatory death donors and could potentially increase both the number and quality of donated organs.

Normothermic Regional Perfusion and Donation After Circulatory Death (Controlled and Uncontrolled): Metabolic Differences and Kidney Transplantation Evolution

OBJECTIVE

To analyze metabolic differences during normothermic regional perfusion (NRP) between the dissimilar types of donation after circulatory death, uncontrolled (uDCD) and controlled (cDCD), and the evolution of the transplanted kidneys.

METHODS

Observational, prospective, cohort study. We included patients from uDCD and cDCD maintained with NRP in 2017. Six consecutive blood gases were collected with determination of pH and lactic acid. Creatinine levels were monitored at 24 hours, 3 months, and 6 months after transplant and the need for renal replacement therapy was evaluated. Descriptive statistical analysis was performed, presenting the qualitative variables as frequencies and percentages, and quantitative as mean ± SD or median (interquartile range [IQR]). We used χ² testing for bivariate analysis of qualitative variables.

RESULTS

We collected 18 donors. Fifteen out of 18 (83.3%) were men with a median of 51 years (IQR, 46-60). Eleven out of 18 (61.1%) were cDCD and 7 out of 18 (38.9%) were uDCD. The blood gas results are illustrated in Table 1. A total of 28 renal transplants were obtained with a median age of 47 years (IQR, 45-57); 83% were male. Ten out of 28 (35.7%) came from uDCD and 18 out of 28 (64.7%) from cDCD. Table 2 shows the monitoring of the creatinine values of the recipients after the transplantation.

CONCLUSIONS

There are more metabolic disorders in our series in uDCD organ donation compared with cDCD. The recovery of the renal function of organs from uDCD is slower than that of cDCD, however; the tendency is toward normality.

Update of a Systematic Review of Autoresuscitation After Cardiac Arrest

OBJECTIVES

There has been a growth in publications focusing on the phenomena of autoresuscitation in recent years. In 2010, we systematically reviewed the medical literature with the primary objective of summarizing the evidence on the timing of autoresuscitation. Healthcare professionals have continued to voice concerns regarding the potential for autoresuscitation. With this in mind, the objective of this brief report is to update the results of our original review of autoresuscitation.

DATA SOURCES

We applied the same search strategy described in our original article to update our findings to include articles published from January 2009 to September 2016.

STUDY SELECTION AND DATA EXTRACTION

We screened an additional 1,859 citations, after duplicates were removed, and then assessed 46 full-text articles for eligibility, from which 15 studies were included for data extraction.

DATA SYNTHESIS

During the time period of this review, there have been 1) 10 additional adult and three pediatric case reports of autoresuscitation in patients after cessation of cardiopulmonary resuscitation; in those cases with continuous monitoring and confirmation of circulation, the longest events are reported to be 10 and 2 minutes, respectively for adults and children; 2) six adults (4%, total n = 162) with autoresuscitation events reported from two observational studies and one chart review of patients undergoing withdrawal of life-sustaining therapy; the longest time reported to be 89 seconds with electrocardiogram and invasive arterial blood pressure monitoring and 3 minutes with electrocardiogram monitoring only; 3) 12 pediatric patients studied with vital sign monitoring during withdrawal of life-sustaining therapy without any reports of autoresuscitation.

CONCLUSIONS

Although case reports of autoresuscitation are hampered by variability in observation and monitoring techniques, autoresuscitation has now been reported in adults and children, and there appears to be a distinction in timing between failed cardiopulmonary resuscitation and withdrawal of life-sustaining therapy. Although additional prospective studies are required to clarify the frequency and predisposing factors associated with this phenomenon, clinical decision-making regarding patient management under uncertainty is required nonetheless. Both adult and pediatric healthcare professionals should be aware of the possibility of autoresuscitation and monitor their patients accordingly before diagnosing death.

Normothermic perfusion and outcomes after liver transplantation

Ischemia has been a persistent and largely unavoidable element in solid organ transplantation, contributing to graft deterioration and adverse post-transplant outcomes. In liver transplantation, where available organs arise with greater frequency from marginal donors (i.e., ones that are older, obese, and/or declared dead following cardiac arrest through the donation after circulatory death process), there is increasing interest using dynamic perfusion strategies to limit, assess, and even reverse the adverse effects of ischemia in these grafts. Normothermic perfusion, in particular, is used to restore the flow of oxygen and other metabolic substrates at physiological temperatures. It may be used in liver transplantation both in situ following cardiac arrest in donation after circulatory death donors or during part or all of the ex situ preservation phase. This review article addresses issues relevant to use of normothermic perfusion strategies in liver transplantation, including technical and logistical aspects associated with establishing and maintaining normothermic perfusion in its different forms and clinical outcomes that have been reported to date.

In situ normothermic perfusion of livers in controlled circulatory death donation may prevent ischemic cholangiopathy and improve graft survival

Livers from controlled donation after circulatory death (DCD) donors suffer a higher incidence of nonfunction, poor function, and ischemic cholangiopathy. In situ normothermic regional perfusion (NRP) restores a blood supply to the abdominal organs after death using an extracorporeal circulation for a limited period before organ recovery. We undertook a retrospective analysis to evaluate whether NRP was associated with improved outcomes of livers from DCD donors. NRP was performed on 70 DCD donors from whom 43 livers were transplanted. These were compared with 187 non-NRP DCD donor livers transplanted at the same two UK centers in the same period. The use of NRP was associated with a reduction in early allograft dysfunction (12% for NRP vs. 32% for non-NRP livers, P = .0076), 30-day graft loss (2% NRP livers vs. 12% non-NRP livers, P = .0559), freedom from ischemic cholangiopathy (0% vs. 27% for non-NRP livers, P < .0001), and fewer anastomotic strictures (7% vs. 27% non-NRP, P = .0041). After adjusting for other factors in a multivariable analysis, NRP remained significantly associated with freedom from ischemic cholangiopathy (P < .0001). These data suggest that NRP during organ recovery from DCD donors leads to superior liver outcomes compared to conventional organ recovery.

Survival advantage for patients accepting the offer of a circulatory death liver transplant

BACKGROUND & AIMS

Donation after circulatory death (DCD) in the UK has tripled in the last decade. However, outcomes following DCD liver transplantation are worse than for donation after brainstem death (DBD) liver transplants. This study examines whether a recipient should accept a "poorer quality" DCD organ or wait longer for a "better" DBD organ.

METHODS

Data were collected on 5,825 patients who were registered on the elective waiting list for a first adult liver-only transplant and 3,949 patients who received a liver-only transplant in the UK between 1 January 2008 and 31 December 2015. Survival following deceased donor liver transplantation performed between 2008 and 2015 was compared by Cox regression modelling to assess the impact on patient survival of accepting a DCD liver compared to deferring for a potential DBD transplant.

RESULTS

A total of 953 (23%) of the 3,949 liver transplantations performed utilised DCD donors. Five-year post-transplant survival was worse following DCD than DBD transplantation (69.1% [DCD] vs. 78.3% [DBD]; p <0.0001: adjusted hazard ratio [HR] 1.65; 95% CI 1.40-1.94). Of the 5,798 patients registered on the transplant list, 1,325 (23%) died or were removed from the list without receiving a transplant. Patients who received DCD livers had a lower risk-adjusted hazard of death than those who remained on the waiting list for a potential DBD organ (adjusted HR 0.55; 95% CI 0.47-0.65). The greatest survival benefit was in those with the most advanced liver disease (adjusted HR 0.19; 95% CI 0.07-0.50).

CONCLUSIONS

Although DCD liver transplantation leads to worse transplant outcomes than DBD transplantation, the individual's survival is enhanced by accepting a DCD offer, particularly for patients with more severe liver disease. DCD liver transplantation improves overall survival for UK listed patients and should be encouraged.

LAY SUMMARY

This study looks at patients who require a liver transplant to save their lives; this liver can be donated by a person who has died either after their heart has stopped (donation after cardiac death [DCD]) or after the brain has been injured and can no longer support life (donation after brainstem death [DBD]). We know that livers donated after brainstem death function better than those after cardiac death, but there are not enough of these livers for everyone, so we wished to help patients decide whether it was better for them to accept an early offer of a DCD liver than waiting longer to receive a "better" liver from a DBD donor. We found that patients were more likely to survive if they accepted the offer of a liver transplant as soon as possible (DCD or DBD), especially if their liver disease was very severe.

Direct Procurement of Donor Heart With Normothermic Regional Perfusion of Abdominal Organs

PURPOSE

We wanted to evaluate if direct procurement of the heart is possible in combination with normothermic regional perfusion of abdominal organs in donors after circulatory death.

DESCRIPTION

A donation after circulatory death pathway was used for a 41-year-old woman after an irreversible brain injury. After meeting criteria for the organ donation, the heart was retrieved and re-animated on ex situ perfusion system, and abdominal organs were perfused with normothermic regional perfusion.

EVALUATION

All the donated organs and their recipients had excellent short-term outcome.

CONCLUSIONS

We demonstrated a successful combination of direct procurement of the heart and normothermic regional perfusion of the abdominal organs.

The efficacy of extracorporeal membrane oxygenation in liver transplantation from non-heart-beating donors: A systemic review and meta-analysis

BACKGROUND

A systematic review and meta-analysis was made to see whether extracorporeal membrane oxygenation (ECMO) in liver transplantation could improve non-heart-beating donors (NHBDs) recipients' outcomes compared with donors after brain death (DBDs) recipients.

METHODS

We searched MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials for eligible studies. The study eligible criteria are cohort or case-control studies using ECMO in all NHBDs; studies involved a comparison group of DBDs; and studies evaluated 1-year graft and patient survival rate in NHBDs and DBDs groups.

RESULTS

Four studies with 704 patients fulfilled the inclusion criteria. The pooled odds ratio (OR) of 1-year patient survival rate in NHBDs recipients compared with DBDs recipients was 0.8 (95% confidence interval [CI], 0.41-1.55). The pooled OR of 1-year graft survival rate in NHBDs recipients compared with DBDs recipients was 0.46 (95% CI, 0.26-0.81). NHBDs recipients were at greater risks to the occurrence of primary nonfunction (PNF) (OR = 7.12, 95% CI, 1.84-27.52) and ischemic cholangiopathy (IC) (OR = 9.46, 95% CI, 2.76-32.4) than DBDs recipients.

CONCLUSIONS

ECMO makes 1-year patient survival acceptable in NHBDs recipients. One-year graft survival rate was lower in NHBDs recipients than in DBDs recipients. Compared with DBDs recipients, the risks to develop PNF and IC were increased among NHBDs recipients.

Kidney transplantation: an attractive and cost-effective alternative for older patients? A cost-utility study

Background

In the elderly, kidney transplantation is associated with increased survival and improved health-related quality of life compared with dialysis treatment. We aimed to study the short-term health economic effects of transplantation in a population of elderly kidney transplant candidates.

Methods

Self-perceived health, quality-adjusted life years (QALYs) and costs were evaluated and compared 1 year before and 1 year after kidney transplantation in patients included in a single-centre prospective study of 289 transplant candidates ≥65 years of age.

Results

Self-perceived health and QALYs both significantly improved after transplantation. At 1 year, the costs per QALY were substantially higher for transplantation (€88 100 versus €76 495), but preliminary analyses suggest a favourable long-term health economic effect.

Conclusions

Kidney transplantation in older kidney transplant recipients is associated with improved health but also with increased costs the first year after engraftment when compared with remaining on the waiting list. Any long-term cost-effectiveness needs to be confirmed in studies with longer observation times.

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.

The need and opportunity for donation after circulatory death worldwide

PURPOSE OF REVIEW

The global shortage of organ donors will not be resolved solely by relying on deceased donation following a brain death determination (DBD). Expansion of deceased donation after circulatory death (DCD) will be needed to address the shortfall of organs for transplantation. Approximately 120 000 organ transplants are performed each year; however, the WHO estimates that this number of transplants only resolves 10% of the annual worldwide transplant need.

RECENT FINDINGS

The report addresses the opportunity of DCD expansion by evaluating the DCD potential that is not being realized, the utility of DCD enabling DBD to emerge in some clinical situations, by the effectiveness of a donor registry in achieving DCD, and by the current clinical research of heart, lung, and liver transplantation from DCD.

SUMMARY

The future of deceased donation must include DCD and ex-vivo organ repair if the organ shortage is to be reconciled even partially to the ongoing demand. Although the religious and legal impediments have been overcome to determine brain death, the possibility of DCD has not been addressed. A program of DCD is feasible in all countries with transplantation services. The excellent results following kidney and lung transplantation suggest opportunities of heart and liver transplantation should be the focus of needed DCD accomplishment in the near future.

Machine perfusion for liver transplantation in the era of marginal organs-New kids on the block

In the face of a critical organ shortage in the Western world, various strategies are employed to expand the donor pool for orthotopic liver transplantation (OLT). Among them is the transplantation of organs from extended criteria donors, a valuable source of liver allografts, however, characterized by potential risks for post-OLT complications and inferior outcomes. In recent years, machine perfusion (MP) of the explanted donor liver as well as regional perfusion techniques has witnessed significant advancements. Here, we aim to discuss different modes of dynamic organ preservation in OLT. These include hypothermic and normothermic MP, hypothermic oxygenated machine perfusion (HOPE), controlled oxygenated rewarming as well as regional perfusion protocols. Over recent years, multiple feasibility trials have demonstrated the clinical prospects of MP. In the context of OLT using organs from extended criteria donors, MP has numerous advantages compared to conventional cold storage, some of which include the preservation and reconditioning of borderline transplantable organs and the viability assessment of high-risk donor allografts. This review aims to address the topic of liver allograft MP, highlighting particularly the current trends in clinical applications and future perspectives. Furthermore, different approaches of liver storage and reconditioning are reviewed in the context of ongoing research.

Machine perfusion of the liver: Which is the best technique to mitigate ischaemia-reperfusion injury?

Longstanding research describes the mechanisms whereby the restoration of blood flow and reoxygenation (reperfusion) aggravates the ischaemic injury caused by a period of anoxia to a donor liver. This phenomenon, called ischaemia-reperfusion injury (IRI), leads to parenchymal cell death, microcirculatory failure, and inflammatory immune response. Clinically, IRI is the main factor responsible for the occurrence of posttransplant graft dysfunction and ischaemic-type biliary lesions. While extended criteria donor livers are more vulnerable to IRI, their utilisation is required to address the shortfall in donor organs. Thus, the mitigation of IRI should drive the setting of a new benchmark for marginal organ preservation. Herein, strategies incorporating different modalities of machine perfusion of the liver to alleviate IRI are discussed in conjunction with advantages and disadvantages of individual protocols. Techniques leading to reperfusion of the liver during machine perfusion (in situ normothermic regional perfusion and ex situ normothermic machine perfusion) may mitigate IRI by shortening the ischaemic period of the organs. This benefit potentially escalates from the minimum level, obtained following just partial alleviation of the ischaemic period, to the maximum level, which can be potentially achieved with ischaemia-free organ transplantation. Techniques that do not lead to reperfusion of the liver during machine perfusion (hypothermic, subnormothermic, and controlled-oxygenated rewarming) optimise mitochondrial oxidative function and replenish cellular energy stores, thereby lowering reactive oxygen species production as well as the activation of downstream inflammatory pathways during reperfusion. Further mechanistic insights into IRI may guide the development of donor-specific protocols of machine perfusion on the basis of the limitations of individual categories of extended criteria donor organs.

Mild hypothermia during the reperfusion phase protects mitochondrial bioenergetics against ischemia-reperfusion injury in an animal model of ex-vivo liver transplantation-an experimental study

The organ preservation paradigm has changed following the development of new ways to preserve organs. The use of machine perfusion to preserve organs appears to have several advantages compared with conventional static cold storage. For liver transplants, the temperature control provided by machine perfusion improves organ preservation. In this experimental study, we measured the effects of different temperatures on mitochondrial bioenergetics during the reperfusion phase. An experimental model of ex-vivo liver transplantation was developed in Wistar rats (Rattus norvegicus). After total hepatectomy, cold static preservation occurred at 4ºC and reperfusion was performed at 37ºC and 32ºC using a Langendorff system. We measured parameters associated with mitochondrial bioenergetics in the livers. Compared with the livers that underwent normothermic reperfusion, mild hypothermia during reperfusion caused significant increases in the mitochondrial membrane potential, the adenosine triphosphate content, and mitochondrial respiration, and a significant reduction in the lag phase (all P < 0.001). Mild hypothermia during reperfusion reduced the effect of ischemia-reperfusion injury on mitochondrial activity in liver tissue and promoted an increase in bioenergetic availability compared with normothermic reperfusion.

A steady decline in pancreas transplantation rates

BACKGROUND/OBJECTIVES

After years of growth in many pancreas transplant programs, UNOS has reported declining transplant numbers in the USA. This precipitating trend urges for an evaluation of the transplant numbers and scientific productivity in the Eurotransplant region and the UK.

METHODS

We performed a trend analysis of pancreas transplantation rates, between 1997 and 2016, adjusting for changes in population size, and an analysis of scientific publications in this field. We used information from the UNOS, Eurotransplant, and UK transplant registry and bibliometric information from the Web of Science database.

RESULTS

Between 2004 and 2016 there was an average annual decline in pancreas transplantation rates per million inhabitants of 3.3% in the USA and 2.5% in the Eurotransplant region. In the UK, transplant numbers showed an average annual decline of 1.0% from 2009 to 2016. Publications in Q1 journals showed an annual change of -2.1% and +20.1%, before 2004, and a change of -3.8% and -5.5%, between 2004 and 2016, for USA and Eurotransplant publications, respectively.

CONCLUSIONS

Adjusting pancreas transplantation rates for changes in population size showed a clear decline in transplant numbers in both the USA and Eurotransplant region, with first signs of decline in the UK. Following this trend, the number of scientific publications in this field have declined worldwide.

Results After Implementing a Program of Intensive Care to Facilitate Organ Donation

A program of intensive care to facilitate organ donation (ICOD) represents one of the ways to increase donation rate following brain death (BD).

OBJECTIVES

To analyze the impact and cost-effectiveness of setting up an ICOD strategy.

METHOD

Retrospective cases of BD donors from the Spanish region La Rioja were included, after implementation of an ICOD program (2011-2016). This was activated in cases of devastating neurologic injury where treatment had been rejected following therapeutic futility criteria. Follow-up of kidney and liver transplant patients with the obtained grafts was carried out.

RESULTS

A total of 134 potential donors were admitted to intensive care unit (ICU), of whom 106 were selected under the ICOD strategy. BD was diagnosed in 108 cases (25 conventional donors, 83 ICOD donors). A total of 21.6% of potential ICOD donors did not evolve to BD, subsequently dying in the ICU. ICOD cases accounted for more than 50% of donors each year. This cohort had an average stay of 2.4 days in the ICU and accounted for a small proportion of total ICU admissions. A total of 68 (81.9%) ICOD donors were finally effective and 146 grafts were extracted, the majority being abdominal organs (liver and kidney). Probability of survival 1 year after liver transplant (ICOD donor) was 90.9%, with 1 case of primary graft failure. Survival 1 year after kidney transplant (ICOD donor) was 92.7%. No differences were detected in survival rates of kidney and liver transplant patients regarding donor type (ICOD vs conventional).

CONCLUSIONS

Implementation of an ICOD program allows an increase in the pool of valid and quality grafts for transplant as well as implying a minimum consumption of intensive medicine resources. The results in transplant patients support this strategy.

The use of ECMO in ICU. Recommendations of the Spanish Society of Critical Care Medicine and Coronary Units

The use of extracorporeal membrane oxygenation systems has increased significantly in recent years; given this reality, the Spanish Society of Critical Intensive Care Medicine and Coronary Units (SEMICYUC) has decided to draw up a series of recommendations that serve as a framework for the use of this technique in intensive care units. The three most frequent areas of extracorporeal membrane oxygenation systems use in our setting are: as a cardiocirculatory support, as a respiratory support and for the maintenance of the abdominal organs in donors. The SEMICYUC appointed a series of experts belonging to the three working groups involved (Cardiological Intensive Care and CPR, Acute Respiratory Failure and Transplant work group) that, after reviewing the existing literature until March 2018, developed a series of recommendations. These recommendations were posted on the SEMICYUC website to receive suggestions from the intensivists and finally approved by the Scientific Committee of the Society. The recommendations, based on current knowledge, are about which patients may be candidates for the technique, when to start it and the necessary infrastructure conditions of the hospital centers or, the conditions for transfer to centers with experience. Although from a physiopathological point of view, there are clear arguments for the use of extracorporeal membrane oxygenation systems, the current scientific evidence is weak, so studies are needed that define more precisely which patients benefit most from the technique and when they should start.

Impact of machine perfusion of the liver on post-transplant biliary complications: A systematic review

AIM

To review the clinical impact of machine perfusion (MP) of the liver on biliary complications post-transplantation, particularly ischaemic-type biliary lesions (ITBL).

METHODS

This systematic review was performed in accordance with the Preferred Reporting Systematic Reviews and Meta-Analysis (PRISMA) protocol. The following databases were searched: PubMed, MEDLINE and Scopus. The keyword “liver transplantation” was used in combination with the free term “machine perfusion”. Clinical studies reporting results of transplantation of donor human livers following ex situ or in situ MP were analysed. Details relating to donor characteristics, recipients, technique of MP performed and post-operative biliary complications (ITBL, bile leak and anastomotic strictures) were critically analysed.

RESULTS

Fifteen articles were considered to fit the criteria for this review. Ex situ normothermic MP was used in 6 studies, ex situ hypothermic MP in 5 studies and the other 4 studies investigated in situ normothermic regional perfusion (NRP) and controlled oxygenated rewarming. MP techniques which have per se the potential to alleviate ischaemia-reperfusion injury: Such as hypothermic MP and NRP, have also reported lower rates of ITBL. Other biliary complications, such as biliary leak and anastomotic biliary strictures, are reported with similar incidences with all MP techniques. There is currently less clinical evidence available to support normothermic MP as a mitigator of biliary complications following liver transplantation. On the other hand, restoration of organ to full metabolism during normothermic MP allows assessment of hepatobiliary function before transplantation, although universally accepted criteria have yet to be validated.

CONCLUSION

MP of the liver has the potential to have a positive impact on post-transplant biliary complications, specifically ITBL, and expand extended criteria donor livers utilisation.