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

Normothermic regional perfusion in liver transplantation from donation after cardiocirculatory death: Technical, biochemical, and regulatory aspects and review of literature

BACKGROUND

Organs from donation after circulatory death (DCD) are increasingly used for liver transplantation, due to the persisting organ shortage and waiting list mortality. However, the use of DCD grafts is still limited by the inferior graft survival rate and the increased risk of primary non-function and biliary complications when compared to brain death donors' grafts.

METHODS

Abdominal normothermic regional perfusion with extracorporeal membrane oxygenation (ECMO) is an in situ preservation strategy. which may mitigate ischemia-reperfusion injuries. and has been proposed to restore blood perfusion after the determination of death thus optimizing liver function before implantation.

RESULTS

In this systematic review, we highlighted the clinical evidence supporting the use of normothermic regional perfusion in DCD liver underlying the pathophysiological mechanisms, and technical, logistic, and regulatory aspects.

CONCLUSIONS

Despite the lack of properly designed, prospective, randomized trials, the current available data suggest beneficial effects of normothermic regional perfusion on clinical outcomes after liver transplantation.

Multiorgan retrieval and preservation of the thoracic and abdominal organs in Maastricht III donors

This editorial describes the indications and technical aspects of the simultaneous retrieval of thoracic and abdominal organs in Maastricht III donors as well as the preservation of such organs until their implantation.

Early United States experience with liver donation after circulatory determination of death using thoraco-abdominal normothermic regional perfusion: A multi-institutional observational study

Mortality on the liver waitlist remains unacceptably high. Donation after circulatory determination of death (DCD) donors are considered marginal but are a potentially underutilized resource. Thoraco-abdominal normothermic perfusion (TA-NRP) in DCD donors might result in higher quality livers and offset waitlist mortality. We retrospectively reviewed outcomes of the first 13 livers transplanted from TA-NRP donors in the US. Nine centers transplanted livers from 8 organ procurement organizations. Median donor age was 25 years; median agonal phase was 13 minutes. Median recipient age was 60 years; median lab MELD score was 21. Three patients (23%) met early allograft dysfunction (EAD) criteria. Three received simultaneous liver-kidney transplants; neither had EAD nor delayed renal allograft function. One recipient died 186 days post-transplant from sepsis but had normal pre-sepsis liver function. One patient developed a biliary anastomotic stricture, managed endoscopically; no recipient developed clinical evidence of ischemic cholangiopathy (IC). Twelve of 13 (92%) patients are alive with good liver function at 439 days median follow-up; 1 patient has extrahepatic recurrent HCC. TA-NRP DCD livers in these recipients all functioned well, particularly with respect to IC, and provide a valuable option to decrease deaths on the waiting list. This article is protected by copyright. All rights reserved.

Kidney transplant outcome of expanded criteria donors after circulatory death

The increase in the number of patients on the kidney transplant waiting list has led to an attempt to increase the number of potential donors by incorporating candidates that previously would not have been considered optimal, including donors after cardiac death (DCD) and those with "expanded" criteria (ECD). Recipients of controlled DCD (cDCD) grafts suffer more delayed graft function (DGF), but have a long-term evolution comparable to those of brain-dead donors, which has allowed an increase in the number of cDCD transplants in different countries in recent years. In parallel, the use of cDCD with expanded criteria (cDCD/ECD) has increased in recent years in different countries, allowing the waiting list for kidney transplantation to be shortened. The use of these grafts, although associated with a higher frequency of DGF, offers similar or only slightly lower long-term graft survival than those of brain death donors with expanded criteria. Different studies have observed that cDCD/ECD graft recipients have worse kidney function than cDCD/standard and DBD/ECD. Mortality associated with cDCD/ECD graft transplantation mostly relates to the recipient age. Patients who receive a cDCD/≥60 graft have better survival than those who continue on the waiting list, although this fact has not been demonstrated in recipients of cDCD/>65 years. The use of this type of organ should be accompanied by the optimization of surgical times and the shortest possible cold ischemia.

Kidney Transplants From Donors on Extracorporeal Membrane Oxygenation Prior to Death Are Associated With Better Long-Term Renal Function Compared to Donors After Circulatory Death

Donation after circulatory death (DCD) allows expansion of the donor pool. We report on 11 years of Italian experience by comparing the outcome of grafts from DCD and extracorporeal membrane oxygenation (ECMO) prior to death donation (EPD), a new donor category. We studied 58 kidney recipients from DCD or EPD and collected donor/recipient clinical characteristics. Primary non function (PNF) and delayed graft function (DGF) rates, dialysis need, hospitalization duration, and patient and graft survival rates were compared. The estimated glomerular filtration rate (eGFR) was measured throughout the follow-up. Better clinical outcomes were achieved with EPD than with DCD despite similar graft and patient survival rates The total warm ischemia time (WIT) was longer in the DCD group than in the EPD group. Pure WIT was the highest in the class II group. The DGF rate was higher in the DCD group than in the EPD group. PNF rate was similar in the groups. Dialysis need was the greatest and hospitalization the longest in the class II DCD group. eGFR was lower in the class II DCD group than in the EPD group. Our results indicate good clinical outcomes of kidney transplants from DCD despite the long “no-touch period” and show that ECMO in the procurement phase improves graft outcome, suggesting EPD as a source for pool expansion.

Controlled Donation After Circulatory Death Program: Analysis and Results at a Tertiary Care Hospital

BACKGROUND

The objective of the study was to evaluate the impact in organs obtained and transplanted from controlled donation after circulatory death (cDCD).

METHODS

Transplants from cDCD donors performed at the Hospital Universitario Marqués de Valdecilla from the beginning of the program (December 2013) to December 2020 were evaluated. All procedures were performed with normothermic regional perfusion. Donors after brain death (DBDs) during the same period were used as a control group.

RESULTS

A total of 95 donors after cardiac death and 152 DBDs were included. Age was similar in both groups (60 years [IQR, 53-68 years vs 62 years {IQR, 51-79 years]; P = .390). The number of organs recovered per donor was higher in the DBD group (4 [IQR, 3-5] vs 3 [IQR, 2-4], P < .001], as well as the number of transplanted organs (4 [IQR, 2-4] vs 2 [IQR, 2-4]; P = .002]. However, the number of noneffective donors was similar. DBDs presented a higher rate of liver donation (30.5% vs 46.7%; P = .012), lung donation (25.3% vs 38.2%; P = .036), and cardiac donation (1.1% vs 21.7%; P < .001) with respect to the donors after cardiac death group, but kidney and pancreatic donation were similar.

CONCLUSIONS

The cDCD with normothermic regional perfusion program is fully established in our center. The age of the cDCD donor has increased with experience and it is currently identical to the control group (DBD). After overcoming the learning curve, cDCD is a multiorgan donation that presents an excellent profitability in the number of organs extracted and transplanted.

Successful lung transplantation with graft recovered after thoracoabdominal normothermic perfusion from donor after circulatory death

Lung transplantation with lungs procured from donors after circulatory death (DCD) has been established as an alternative technique to traditional donation after brain death (DBD) with comparable outcomes. Recently, in situ thoracoabdominal normothermic regional perfusion (TA-NRP) has emerged as a novel technique employed in the procurement of cardiac allografts after circulatory death. TA-NRP, in contrast to ex situ machine perfusion, has the advantage of allowing in situ assessment of donor organs prior to final acceptance. However, there are some concerns that this technique may adversely impact the quality of lung allografts. Here, we present a case of a successful bilateral sequential lung transplantation in a patient with postinflammatory pulmonary fibrosis due to acute respiratory distress syndrome (ARDS), with lungs procured after normothermic in situ lung perfusion. Apart from the lungs, heart, liver, and kidneys were also successfully transplanted from this donor.

Inulin Clearance During Ex vivo Normothermic Machine Perfusion as a Marker of Renal Function

Normothermic machine perfusion (NMP) offers a unique opportunity to objectively assess donor organ quality. This study describes the evaluation of inulin clearance as a potential marker for the ex vivo function of porcine kidneys during NMP. The function assessment was performed in both kidneys from slaughterhouse pigs (n = 20) and kidneys from pigs in a laboratory setting (n = 28). The kidneys were exposed to different warm ischemia times (WIT). After a period of static cold storage, the kidneys underwent a 4-hour NMP with autologous whole blood. Inulin clearance, hemodynamic parameters, and urine output were measured. Based on the inulin excretion behavior laboratory pig kidneys were assigned to three classes (functional, limited functional, and nonfunctional), slaughterhouse pig kidneys to two classes (limited functional and nonfunctional), respectively. Contrary to the marginal kidneys of the slaughterhouse pigs, the functional variation of kidneys of the laboratory pigs was associated with the WIT. A correlation between functional kidneys and a WIT less than 25 min was shown. Because none of the slaughterhouse pig kidneys could be assigned to the functional class, only the laboratory pig kidneys were used for examinations with functional markers. Renal blood flow and urine output during NMP correlated significantly (p < 0.01) with ex vivo kidney function. This study demonstrated that inulin is a marker of high quality for the evaluation of suggested kidney function after NMP with whole blood. Furthermore, surrogate markers measured during NMP can be used to describe and predict the physiologic behavior of kidneys before transplantation.

Outcome of Liver Transplants Using Donors After Cardiac Death With Normothermic Regional Perfusion

BACKGROUND AND AIMS

The incorporation of normothermic regional perfusion (NRP) to donors after cardiac death (DCD) allows the recovery of liver grafts without the deleterious effects on graft survival the super-rapid technique may cause. The aim of the present report is to determine if the use of NRP in Maastricht type III DCD donors achieves short- and medium-term results comparable to donors after brain death (DBD).

PATIENTS AND METHODS

This is an observational cohort study including 117 liver transplants executed between November 2016 and April 2021, divided into NRP (n = 39) and DBD (n = 78).

RESULTS

Donors were younger in the NRP group (NRP 52 vs DBD 59.4 years; P < .005). Liver recipients in each study group were of similar age and severity of liver disease, although the predominant transplant indication in the NRP group was hepatocellular carcinoma. No differences in ischemia times were found. The incidence of early allograft disfunction and primary nonfunction was balanced between NRP and DBD. Eight patients required retransplant, all of them in the DBD group. No differences were found in biliary complications (NRP 12% vs DBD 5%; P = .104). Ischemic cholangiopathy affected a single DBD patient. Graft survival's Kaplan Meier curve shows a better outcome in the NRP group, although the difference did not reach significance (P = .075).

CONCLUSIONS

The incorporation of perfusion machines, and specifically the NPR in situ, converts suboptimal liver grafts such as DCD into organs comparable to DBDs.

The economic impact of machine perfusion technology in liver transplantation

INTRODUCTION

Several clinical studies have demonstrated the safety, feasibility, and efficacy of machine perfusion in liver transplantation, although its economic outcomes are still underexplored. This review aimed to examine the costs related to machine perfusion and its associated outcomes.

METHODS

Expert opinion of several groups representing different machine perfusion modalities. Critical analysis of the published literature reporting the economic outcomes of the most used techniques of machine perfusion in liver transplantation (normothermic and hypothermic ex situ machine perfusion and in situ normothermic regional perfusion).

RESULTS

Machine perfusion costs include disposable components of the perfusion device, perfusate components, personnel and facility fees, and depreciation of the perfusion device or device lease fee. The limited current literature suggests that although this upfront cost varies between perfusion modalities, its use is highly likely to be cost-effective. Optimization of the donor liver utilization rate, local conditions of transplant programs (long waiting list times and higher MELD scores), a decreased rate of complications, changes in logistics, and length of hospital stay are potential cost savings points that must highlight the expected benefits of this intervention. An additional unaccounted factor is that machine perfusion optimizing donor organ utilization allows patients to be transplanted earlier, avoiding clinical deterioration while on the waiting list and the costs associated with hospital admissions and other required procedures.

CONCLUSION

So far, the clinical benefits have guided machine perfusion implementation in liver transplantation. Albeit there is data suggesting the economic benefit of the technique, further investigation of its costs to healthcare systems and society and associated outcomes is needed.

Novel Organ Perfusion and Preservation Strategies in Controlled Donation After Circulatory Death in Pancreas and Kidney Transplantation

BACKGROUND

Kidney and pancreatic transplants from controlled donation after circulatory death donors are vulnerable to ischemia-reperfusion injuries. In this context of transplant shortage, there is a need to optimize the function of these transplants and to develop novel perfusion and preservation strategies in controlled donation after circulatory death in kidney and pancreatic transplants.

IN SITU PERFUSION AND PRESERVATION STRATEGIES

In situ regional normothermic perfusion improves the outcome of kidney transplants from controlled donation after circulatory death and provides equivalent results for the kidney from brain-dead donors. In situ regional normothermic perfusion is under investigation for pancreatic transplants.

EX SITU PERFUSION AND PRESERVATION STRATEGIES

Perfusion on hypothermic machine perfusion is highly recommended for the kidney from controlled donation after cardiac death. Hypothermic oxygenated perfusion machine decreases the rate of graft rejection and graft failure in kidney transplantation. Ex situ normothermic perfusion is an easy way to assess renal function. In the future, kidney transplants could benefit from drug therapy during ex situ normothermic perfusion. In pancreas transplantation, hypothermic machine perfusion and ex situ normothermic perfusion present encouraging results in preclinical studies.

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

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

A retrievable, dual-chamber stent protects against warm ischemia of donor organs in a model of donation after circulatory death

BACKGROUND

Ischemic injury during the agonal period of donation after circulatory death donors remains a significant barrier to increasing abdominal transplants. A major obstacle has been the inability to improve visceral perfusion, while at the same time respecting the ethics of the organ donor. A retrievable dual-chamber stentgraft could potentially isolate the organ perfusion from systemic hypotension and hypoxia, without increasing cardiac work or committing the donor.

METHODS

Retrievable dumbbell-shaped stents were laser welded from nitinol wire and covered with polytetrafluoroethylene. Yorkshire pigs were assigned to either agonal control or dumbbell-shaped dual-chamber stentgraft. A central lumen maintained aortic flow, while an outer visceral chamber was perfused with oxygenated blood. A 1-hour agonal phase of hypoxia and hypotension was simulated. Stents were removed by simple sheath advancement. Cardiac monitoring, labs, and visceral flow were recorded followed by recovery of the animal to a goal of 48 hours.

RESULTS

Cardiac stress did not increase during stent deployment. Visceral pO2 and flow were dramatically improved in stented animal relative to control animals. Five of 7 control animals were killed after renal failure complications, whereas all stent animals survived. Histology confirmed increased ischemic changes among control kidneys compared to stented animals.

CONCLUSION

A dual-chamber stent improved outcomes after a simulated agonal phase. The stent did not increase cardiac work, thus respecting a key ethical consideration. The ability of a dual-chamber stent to prevent ischemia during organ recovery may become a powerful tool to address the critical donor organ shortage.

Development of the Eurotransplant Discard Risk Index to Predict Acceptance of Livers for Transplantation: A Retrospective Database Analysis

OBJECTIVES

The utilization of liver allografts could be optimized if nonacceptance is predicted. This study aimed to evaluate the prognostic ability of an updated Discard Risk Index in Eurotransplant.

MATERIALS AND METHODS

Potential deceased donors from January 2010 to December 2015 who had been reported to Eurotransplant were included in our analyses. Liver utilization was defined by transplant status as the primary outcome to evaluate the performance of the Eurotransplant-developed Discard Risk Index.

RESULTS

Of 11670 potential livers, 9565 (81%) were actually transplanted. Donor sex, age, history of diabetes, drug abuse, use of vasopressors, body mass index category, serum sodium, cause of death, donor type, and levels of C-reactive protein, bilirubin, aspartate and alanine aminotransferases, international normalized ratio, and gamma-glutamyltranspeptidase were associated with discard and combined in the Eurotransplant-developed Discard Risk Index. Correlation between the two Discard Risk Indexes was high (r = 0.86), and both achieved high C statistics of 0.72 and 0.75 (P < .001), respectively. Despite strong calibration, discard rates of 0.8% for overall donors and 6% of donors after circulatory death could be predicted with 80% accuracy.

CONCLUSIONS

The Eurotransplant-developed Discard Risk Index showed a high prognostic ability to predict liver utilization in a European setting. The model could therefore be valuable for identifying livers at high risk of not being transplanted in an early stage. These organs might profit the most from modified allocation strategies or advanced preservation techniques.

Role of normothermic perfusion 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.

Impact of the duration of normothermic regional perfusion on the results of liver transplant from controlled circulatory death donors: A retrospective, multicentric study

In France, the program of controlled donation after circulatory death (cDCD) was established with routine use of in situ normothermic regional perfusion (NRP). There is currently no consensus on its optimal duration. The purpose was to assess the impact of NRP duration on liver graft function and biliary outcomes. One-hundred and fifty-six liver recipients from NRP-cDCD donors from six French centers between 2015 and 2019 were included. Primary endpoint was graft function assessed by early allograft dysfunction (EAD, according to Olthoff's criteria) and MEAF (model for early allograft function) score. Overall, three (1.9%) patients had primary non-function, 30 (19.2%) patients experienced EAD, and MEAF score was 7.3 (±1.7). Mean NRP duration was 179 (±43) min. There was no impact of NRP duration on EAD (170±44 min in patients with EAD vs. 181±42 min in patients without, P = .286). There was no significant association between NRP duration and MEAF score (P = .347). NRP duration did neither impact on overall biliary complications nor on non-anastomotic biliary strictures (overall rates of 16.7% and 3.9%, respectively). In conclusion, duration of NRP in cDCD donors does not seem to impact liver graft function and biliary outcomes after liver transplantation. A 1 to 4-h perfusion represents an optimal time window.

Improved short-term outcomes of kidney transplants in controlled donation after the circulatory determination of death with the use of normothermic regional perfusion

Normothermic regional perfusion (NRP) allows the in situ perfusion of organs with oxygenated blood in donation after the circulatory determination of death (DCDD). We aimed at evaluating the impact of NRP on the short-term outcomes of kidney transplants in controlled DCDD (cDCDD). This is a multicenter, nationwide, retrospective study comparing cDCDD kidneys obtained with NRP versus the standard rapid recovery (RR) technique. During 2012-2018, 2302 cDCDD adult kidney transplants were performed in Spain using NRP (n = 865) or RR (n = 1437). The study groups differed in donor and recipient age, warm, and cold ischemic time and use of ex situ machine perfusion. Transplants in the NRP group were more frequently performed in high-volume centers (≥90 transplants/year). Through matching by propensity score, two cohorts with a total of 770 patients were obtained. After the matching, no statistically significant differences were observed between the groups in terms of primary nonfunction (p = .261) and mortality at 1 year (p =  .111). However, the RR of kidneys was associated with a significantly increased odds of delayed graft function (OR 1.97 [95% CI 1.43-2.72]; p < .001) and 1-year graft loss (OR 1.77 [95% CI 1.01-3.17]; p = .034). In conclusion, compared with RR, NRP appears to improve the short-term outcomes of cDCDD kidney transplants.

Advances in Kidney Preservation Techniques and Their Application in Clinical Practice

The use of cold preservation solutions to rapidly flush and cool the kidney followed by static cold storage in ice has been the standard kidney preservation technique for the last 50 y. Nonetheless, changing donor demographics that include organs from extended criteria donors and donation after circulatory death donors have led to the adoption of more diverse techniques of preservation. Comparison of hypothermic machine perfusion and static cold storage techniques for deceased donor kidneys has long been debated and is still contested by some. The recent modification of hypothermic machine perfusion techniques with the addition of oxygen or perfusion at subnormothermic or near-normothermic temperatures are promising strategies that are emerging in clinical practice. In addition, the use of normothermic regional perfusion to resuscitate abdominal organs of donation after circulatory death donors in situ before cold flushing is also increasingly being utilized. This review provides a synopsis of the different types of preservation techniques including their mechanistic effects and the outcome of their application in clinical practice for different types of donor kidney.

How to Preserve Liver Grafts From Circulatory Death With Long Warm Ischemia? A Retrospective Italian Cohort Study With Normothermic Regional Perfusion and Hypothermic Oxygenated Perfusion

BACKGROUND

Donation after circulatory death (DCD) in Italy, given its 20-min stand-off period, provides a unique bench test for normothermic regional perfusion (NRP) and dual hypothermic oxygenated machine perfusion (D-HOPE).

METHODS

We coordinated a multicenter retrospective Italian cohort study with 44 controlled DCD donors, who underwent NRP, to present transplant characteristics and results. To rank our results according to the high donor risk, we matched and compared a subgroup of 37 controlled DCD livers, preserved with NRP and D-HOPE, with static-preserved controlled DCD transplants from an established European program.

RESULTS

In the Italian cohort, D-HOPE was used in 84% of cases, and the primary nonfunction rate was 5%. Compared with the matched comparator group, the NRP + D-HOPE group showed a lower incidence of moderate and severe acute kidney injury (stage 2: 8% versus 27% and stage 3: 3% versus 27%; P = 0.001). Ischemic cholangiopathy remained low (2-y proportion free: 97% versus 92%; P = 0.317), despite the high-risk profile resulting from the longer donor warm ischemia in Italy (40 versus 18 min; P < 0.001).

CONCLUSIONS

These data suggest that NRP and D-HOPE yield good results in DCD livers with prolonged warm ischemia.

Kidney transplant outcomes in elderly recipients with controlled donation after circulatory death or donation after brain death donors: a registry cohort study

The number of kidney transplant (KT) procedures with controlled donation after circulatory death (cDCD) donors has exponentially increased in Spain in recent years, with a parallel increase in donor and recipient acceptance criteria. The outcomes of cDCD-KT have been reported to be comparable to those of KT with donation after brain death (DBD) donors. However, studies in elderly recipients have yielded contradictory results. We performed a registry analysis of 852 KT recipients aged ≥65 years (575 in the DBD-KT group, 277 in the cDCD-KT group) in Catalonia, Spain. Clinical outcomes and survival were compared between DBD-KT and cDCD-KT recipients. The donor and recipient ages were similar between the two groups (71.5 ± 8.7 years for donors, 70.8 ± 4.1 years for recipients). Delayed graft function (DGF) was more frequent among cDCD-KT recipients, without a difference in the rate of primary nonfunction. The 3-year patient and death-censored graft survival rates were similar between DBD-KT and cDCD-KT recipients (78.8% vs. 76.4% and 90.3% vs. 86.6%, respectively). In multivariable analysis, previous cardiovascular disease and DGF were independent risk factors for patient death. The type of donation (cDCD vs. DBD) was not an independent risk factor for patient survival or graft loss. cDCD-KT and DBD-KT provide comparable patient and graft survival in elderly recipients.

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

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

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

Background

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

Methods

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

Results

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

Conclusions

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

Early Allograft Dysfunction and Complications in DCD Liver Transplantation: Expert Consensus Statements From the International Liver Transplantation Society

Livers for transplantation from donation after circulatory death donors are relatively more prone to early and ongoing alterations in graft function that might ultimately lead to graft loss and even patient death. In consideration of this fact, this working group of the International Liver Transplantation Society has performed a critical evaluation of the medical literature to create a set of statements regarding the assessment of early allograft function/dysfunction and complications arising in the setting of donation after circulatory death liver transplantation.

Outcomes From Brain Death Donors With Previous Cardiac Arrest Accepted for Pancreas Transplantation: A Single-center Retrospective Analysis

OBJECTIVE

The aim of the study was to evaluate the effect of cardiac arrest time (CAT) in donors after brain death (DBD) donors on pancreas transplant outcome.

SUMMARY OF BACKGROUND DATA

Results from donors after circulatory death report good outcomes despite warm ischemia times up to 57 minutes. Previous cardiac arrest in DBD has been addressed as a potential risk factor, but duration of the CAT has never been evaluated.

METHODS

We conducted a retrospective analysis including 342 pancreas transplants performed at our center from 2000 to 2016, and evaluated the effect of previous cardiac arrest in DBD (caDBD) on pancreas transplant outcomes.

RESULTS

A total of 49 (14.3%) caDBD were accepted for transplantation [median CAT of 5.0 min (IQR 2.5-15.0)]. Anoxic encephalopathy was most frequent and P-PASS higher (16.9 vs 15.6) in caDBD group when compared with other DBD. No differences were found in all other characteristics evaluated.Graft survival was similar between both groups, as was the incidence of early graft failure (EGF). CAT increased the risk for EGF [OR 1.09 (95% CI, 1.01-1.17)], and the duration of CPR discriminated for EGF [AUC of 0.86 (95% CI, 0.74-0.98)], with a sensitivity and specificity of 100% and 75% at a cutoff of 15 minutes. When evaluated separately, caDBD >15 min increased over 5 times the risk for EGF [HR 5.80 (95% CI, 1.82-18.56); P = 0.003], and these presented fewer days on the ICU (1.0 vs 3.0 d).

CONCLUSION

CaDBD donors are suitable for routine pancreas transplantation without increasing EGF risk, and in those with longer CAT it may be prudent to postpone donation a few days to allow a thorough evaluation of organ damage following cardiac arrest.

The Role of Ex Situ Hypothermic Oxygenated Machine Perfusion and Cold Preservation Time in Extended Criteria Donation After Circulatory Death and Donation After Brain Death

Hypothermic oxygenated machine perfusion (HOPE) has the potential to counterbalance the detrimental consequences of cold and warm ischemia time (WIT) in both donation after brain death (DBD) and donation after circulatory death (DCD). Herein we investigated the protective effects of HOPE in extended criteria donor (ECD) DBD and overextended WIT DCD grafts. The present retrospective case series included 50 livers subjected to end-ischemic HOPE or dual DHOPE in 2 liver transplantation (LT) centers from January 2018 to December 2019. All DCD donors were subjected to normothermic regional perfusion before organ procurement. Results are expressed as median (interquartile range [IQR]). In the study period, 21 grafts were derived from overextended WIT DCD donors (total WIT 54 [IQR, 40-60] minutes and 75% classified as futile), whereas 29 were from ECD DBD. A total of 3 biliary complications and 1 case of ischemia-type biliary lesion were diagnosed. The rate of early allograft dysfunction (EAD) was 20%, and those patients had higher Comprehensive Complication Index scores. Through a changing point analysis, cold preservation time >9 hours was associated with prolonged hospital stays (P = 0.02), higher rates of EAD (P = 0.009), and worst post-LT complications (P = 0.02). Logistic regression analyses indicated a significant relationship between cold preservation time and EAD. No differences were shown in terms of the early post-LT results between LTs performed with DCD and DBD. Overall, our data are fully comparable with benchmark criteria in LT. In conclusion, the application of DHOPE obtained satisfactory and promising results using ECD-DBD and overextended DCD grafts. Our findings indicate the need to reduce cold preservation time also in the setting of DHOPE, particularly for grafts showing poor quality.

Regulations and Procurement Surgery in DCD Liver Transplantation: Expert Consensus Guidance From the International Liver Transplantation Society

Donation after circulatory death (DCD) donors are an increasingly more common source of livers for transplantation in many parts of the world. Events that occur during DCD liver recovery have a significant impact on the success of subsequent transplantation. This working group of the International Liver Transplantation Society evaluated current evidence as well as combined experience and created this guidance on DCD liver procurement. Best practices for the recovery and transplantation of livers arising through DCD after euthanasia and organ procurement with super-rapid cold preservation and recovery as well as postmortem normothermic regional perfusion are described, as are the use of adjuncts during DCD liver procurement.

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

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Background.

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

Methods.

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

Results.

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

Conclusions.

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

Transplantation of kidneys after normothermic perfusion: A single center experience

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Hypothermic oxygenated machine perfusion of the human pancreas for clinical islet isolation: a prospective feasibility study

Due to an increasing scarcity of pancreases with optimal donor characteristics, islet isolation centers utilize pancreases from extended criteria donors, such as from donation after circulatory death (DCD) donors, which are particularly susceptible to prolonged cold ischemia time (CIT). We hypothesized that hypothermic machine perfusion (HMP) can safely increase CIT. Five human DCD pancreases were subjected to 6 h of oxygenated HMP. Perfusion parameters, apoptosis, and edema were measured prior to islet isolation. Five human DBD pancreases were evaluated after static cold storage (SCS). Islet viability, and in vitro and in vivo functionality in diabetic mice were analyzed. Islets were isolated from HMP pancreases after 13.4 h [12.9–14.5] CIT and after 9.2 h [6.5–12.5] CIT from SCS pancreases. Histological analysis of the pancreatic tissue showed that HMP did not induce edema nor apoptosis. Islets maintained >90% viable during culture, and an appropriate in vitro and in vivo function in mice was demonstrated after HMP. The current study design does not permit to demonstrate that oxygenated HMP allows for cold ischemia extension; however, the successful isolation of functional islets from discarded human DCD pancreases after performing 6 h of oxygenated HMP indicates that oxygenated HMP may be a useful technology for better preservation of pancreases.

Optimal donation of kidney transplants after controlled circulatory death

Controlled donation after circulatory death (cDCD) is used for "extended criteria" donors with poorer kidney transplant outcomes. The French cDCD program started in 2015 and is characterized by normothermic regional perfusion, hypothermic machine perfusion, and short cold ischemia time. We compared the outcomes of kidney transplantation from cDCD and brain-dead (DBD) donors, matching cDCD and DBD kidney transplants by propensity scoring for donor and recipient characteristics. The matching process retained 442 of 499 cDCD and 809 of 6185 DBD transplantations. The DGF rate was 20% in cDCD recipients compared with 28% in DBD recipients (adjusted relative risk [aRR], 1.43; 95% confidence interval [CI] 1.12-1.82). When DBD transplants were ranked by cold ischemia time and machine perfusion use and compared with cDCD transplants, the aRR of DGF was higher for DBD transplants without machine perfusion, regardless of the cold ischemia time (aRR with cold ischemia time <18 h, 1.57; 95% CI 1.20-2.03, vs aRR with cold ischemia time ≥18 h, 1.79; 95% CI 1.31-2.44). The 1-year graft survival rate was similar in both groups. Early outcome was better for kidney transplants from cDCD than from matched DBD transplants with this French protocol.

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

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

Kidney transplant outcome of expanded criteria donors after circulatory death

The increase in the number of patients on the kidney transplant waiting list has led to an attempt to increase the number of potential donors by incorporating candidates that previously would not have been considered optimal, including donors after cardiac death (DCD) and those with "expanded" criteria (ECD). Recipients of controlled DCD (cDCD) grafts suffer more delayed graft function (DGF), but have a long-term evolution comparable to those of brain-dead donors, which has allowed an increase in the number of cDCD transplants in different countries in recent years. In parallel, the use of cDCD with expanded criteria (cDCD/ECD) has increased in recent years in different countries, allowing the waiting list for kidney transplantation to be shortened. The use of these grafts, although associated with a higher frequency of DGF, offers similar or only slightly lower long-term graft survival than those of brain death donors with expanded criteria. Different studies have observed that cDCD/ECD graft recipients have worse kidney function than cDCD/standard and brain death/ECD. Mortality associated with cDCD/ECD graft transplantation mostly relates to the recipient age. Patients who receive a cDCD/≥60 graft have better survival than those who continue on the waiting list, although this fact has not been demonstrated in recipients of cDCD/>65 years. The use of this type of organ should be accompanied by the optimization of surgical times and the shortest possible cold ischemia.

Heart transplantation from controlled donation after circulatory death using thoracoabdominal normothermic regional perfusion and cold storage

BACKGROUND

Heart transplantation from controlled donation after the circulatory determination of death (cDCDD) may be an option to increase the pool of grafts for transplantation.

MATERIALS AND METHODS

Initial experiences on cDCDD heart transplantation were based on the direct procurement of the heart followed by preservation with ex situ perfusion devices. Later, the use of thoracoabdominal normothermic regional perfusion (TA-NRP) has emerged as an option to recover hearts. We present a case of a heart transplant using a graft from controlled donation after circulatory death. Cardiac preservation was performed by postmortem TA-NRP followed by cold storage. Ex situ perfusion device was not used.

DISCUSSION AND CONCLUSION

This is one of the first published cases of a controlled donation after circulatory death heart retrieved using only TA-NRP and successfully transplanted.

Donation after circulatory death and liver transplantation: a cohort study

Donations after circulatory death (DCD) are still challenging in Italy because of prolonged ischemia time (tWIT) due to the law and logistical issues. This cohort study was primarily aimed at assessing the association between successful transplantation and DCD types in the North Italy Transplant program. Adjusted risk ratios (RR) and 95% confidence intervals (CIs) for type III versus type II DCD were estimated using a Poisson regression model with a robust error variance. All consecutive DCD between 2008 and 2020 were included. Among 142 DCD, 102 were eligible for liver donation, and 96 were proposed: 68/69 (99%) and 28/33 (85%) type III and II DCD, respectively. Sixty-nine livers were recovered, 51/68 (75%) from type III and 18/28 (64%) from type II DCD, respectively (RR: 1.18; 95% CI: 0.87-1.60). After ex-vivo perfusion, 50/68 (74%) and 14/28 (50%) livers from type III and type II DCD were transplanted (RR: 1.49; 95% CI: 1.01-2.19). The estimate decreased after further controlling for tWIT (RR: 1.11; 95% CI: 0.55-2.24). Five patients (7.8%) experienced a PNF, 3/50 and 2/14 from type III and type II DCD, respectively. Type III DCD livers were more likely to be transplanted than type II. Warm ischemia time might explain this difference.

Is donation after circulatory determination of death feasible for pediatric patients in italy?

To determine the potential effect of a donation after cardiac death active program on the number of organ donors in a Italian Pediatric Intensive Care Unit (PICU). We conducted a retrospective study of all deaths in PICU of an academic Children Hospital between 2012 and 2020, tracing the organ donation activity. Patients were categorized as brain deaths, deaths despite maximal resuscitation, and deaths after withdrawal or limitation of life support. Patient demographics, premortem physiology, end-of-life circumstances, and functional warm ischemia time were recorded. Eligible donors after cardiac death were identified by the absence of medical contraindication and functional warm ischemia time <60 minutes. Of 124 deaths that occurred during the study period, 34 met criteria for brain death, 23 were potential donors, and 13 became actual donors. Of the remaining 90 patients that met criteria for cardiac death, 66 died despite maximal resuscitation, 24 died after withdrawal or limitation of care and between them 13 were identified as theoretically eligible DCD donors. Of these, 5 patients had a functional warm ischemia time of <1 hour and were potential candidates for DCD of 10 kidneys and 2 lungs. Even if few children could have been eligible for DCD in the study period, an active program could have been able to increase the number of potential organ donors by 20% in the last eight years at our institution. DCD deserves to be explored in Italy as a new option for children.

A dedicated Y-shaped percutaneous ECMO cannula for femoral 2-in-1 vascular access during high-risk procedures

High-risk transcatheter procedures requiring hemodynamic support are growing and require multiple vascular access that may be challenging in cases of peripheral artery disease or lack of radial access and exposure to a higher risk of vascular complications. We report the novel utilization of a Y-shaped arterial extracorporeal membrane oxygenation (ECMO) cannula used as a single femoral access to perform percutaneous coronary intervention (PCI) and aortography during high-risk transcatheter aortic valve replacement (TAVR). The utilization of this 2-in-1 ECMO cannula may simplify vascular access and reduce vascular and bleeding complications during high-risk ECMO-supported transcatheter procedures.

Spanish experience with heart transplants from controlled donation after the circulatory determination of death using thoraco-abdominal normothermic regional perfusion and cold storage

Heart transplantation from controlled donation after the circulatory determination of death (cDCDD) may help to increase the availability of hearts for transplantation. During 2020, four heart transplants were performed at three different Spanish hospitals based on the use of thoraco-abdominal normothermic regional perfusion (TA-NRP) followed by cold storage (CS). All donors were young adults <45 years. The functional warms ischemic time ranged from 8 to 16 minutes. In all cases, the heart recovered sinus rhythm within 1 minute of TA-NRP. TA-NRP was weaned off or decreased <1L within 25 minutes. No recipient required mechanical support after transplantation and all were immediately extubated and discharged home (median hospital stay: 21 days) with an excellent outcome. Four livers, eight kidneys, and two pancreata were also recovered and transplanted. All abdominal grafts recipients experienced an excellent outcome. The use of TA-NRP makes heart transplantation feasible and allows assessing heart function before organ procurement without any negative impact on the preservation of abdominal organs. The use of TA-NRP in cDCDD heart donors in conjunction with cold storage following retrieval can eliminate the need to use ex situ machine perfusion devices, making cDCDD heart transplantation economically possible in other countries.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Expanding controlled donation after the circulatory determination of death: statement from an international collaborative

A decision to withdraw life-sustaining treatment (WLST) is derived by a conclusion that further treatment will not enable a patient to survive or will not produce a functional outcome with acceptable quality of life that the patient and the treating team regard as beneficial. Although many hospitalized patients die under such circumstances, controlled donation after the circulatory determination of death (cDCDD) programs have been developed only in a reduced number of countries. This International Collaborative Statement aims at expanding cDCDD in the world to help countries progress towards self-sufficiency in transplantation and offer more patients the opportunity of organ donation. The Statement addresses three fundamental aspects of the cDCDD pathway. First, it describes the process of determining a prognosis that justifies the WLST, a decision that should be prior to and independent of any consideration of organ donation and in which transplant professionals must not participate. Second, the Statement establishes the permanent cessation of circulation to the brain as the standard to determine death by circulatory criteria. Death may be declared after an elapsed observation period of 5 min without circulation to the brain, which confirms that the absence of circulation to the brain is permanent. Finally, the Statement highlights the value of perfusion repair for increasing the success of cDCDD organ transplantation. cDCDD protocols may utilize either in situ or ex situ perfusion consistent with the practice of each country. Methods to accomplish the in situ normothermic reperfusion of organs must preclude the restoration of brain perfusion to not invalidate the determination of death.

Beyond Ice and the Cooler: Machine Perfusion Strategies in Liver Transplantation

Machine perfusion (MP) has emerged as a promising preservation technique to reduce the risks associated with transplant of high risk (steatotic, elderly, and donation after circulatory death) hepatic allografts. Multiple strategies for MP are under investigation. MP facilitates assessment of organ viability and enables liver-directed therapy before transplant. Clinical trials suggest MP may improve the use of hepatic allografts, mitigate ischemia-reperfusion injury, and reduce the incidences of early allograft dysfunction, biliary complications, and ischemic cholangiopathy. As MP sees more widespread use outside of trial settings, more investigation will be needed to establish optimal application of this technology.

Complications during multiorgan retrieval and pancreas preservation

In pancreas transplantation, complications can arise at each step of the process, from the initial selection of donors and recipients through the surgical technique itself and the post-operative period, when lifelong immunosuppression is required. In the early steps, careful retrieval and preservation of the pancreas are crucial for the viability of the organ and ultimate success of the transplant. The pancreas is a low-flow gland, making it highly sensitive to transplantation conditions and presenting risk of pancreatitis due to periods of ischemia. The two groups of donors - after brain death (DBD) or after cardiac arrest (DCD) - require different strategies of retrieval and preservation to avoid or reduce the risk of complications developing during and after the transplantation. For DBD donor transplantation, multiorgan retrieval and cold preservation is the conventional technique. Asystole donor (DCD) transplantation, in contrast, can benefit from the newest technologies, such as hypothermic and especially normothermic preservation machines (referred to as NECMO), to optimize organ preservation. The latter has led to an increase in the pool of donors by facilitating recuperation of organs for transplantation that would have been discarded otherwise.

Recurrent acute kidney injury: predictors and impact in a large population-based cohort

BACKGROUND

This study examined the impact of recurrent episodes of acute kidney injury (AKI) on patient outcomes.

METHODS

The Welsh National electronic AKI reporting system was used to identify all cases of AKI in patients ≥18 years of age between April 2015 and September 2018. Patients were grouped according to the number of AKI episodes they experienced with each patient's first episode described as their index episode. We compared the demography and patient outcomes of those patients with a single AKI episode with those patients with multiple AKI episodes. Analysis included 153 776 AKI episodes in 111 528 patients.

RESULTS

Of those who experienced AKI and survived their index episode, 29.3% experienced a second episode, 9.9% a third episode and 4.0% experienced fourth or more episodes. Thirty-day mortality for those patients with multiple episodes of AKI was significantly higher than for those patients with a single episode (31.3% versus 24.9%, P < 0.001). Following a single episode, recovery to baseline renal function at 30 days was achieved in 83.6% of patients and was significantly higher than for patients who had repeated episodes (77.8%, P < 0.001). For surviving patients, non-recovery of renal function following any AKI episode was significantly associated with a higher probability of a further AKI episode (33.4% versus 41.0%, P < 0.001). Furthermore, with each episode of AKI the likelihood of a subsequent episode also increased (31.0% versus 43.2% versus 51.2% versus 51.7% following a first, second, third and fourth episode, P < 0.001 for all comparisons).

CONCLUSIONS

The results of this study provide an important contribution to the debate regarding the need for risk stratification for recurrent AKI. The data suggest that such a tool would be useful given the poor patient and renal outcomes associated with recurrent AKI episodes as highlighted by this study.

Transplantation of a heart donated after circulatory death via thoraco-abdominal normothermic regional perfusion and results from the first Spanish case

BACKGROUND

Controlled donation after circulatory death (cDCD) has emerged as one of the main strategies for increasing the organ donor pool. Because of the ischemic injury that follows the withdrawal of life-sustaining therapies, hearts from cDCD donors have not been considered for transplantation until recently. The ex-situ perfusion of hearts directly procured from cDCD donors has been used to allow the continuous perfusion of the organ and the assessment of myocardial viability prior to transplantation. Based on our experience with abdominal normothermic regional perfusion in cDCD, we designed a protocol to recover and validate hearts from cDCD donors using thoraco-abdominal normothermic regional perfusion without the utilization of an ex-situ device.

CASE PRESENTATION

We describe the first case of a cDCD heart transplant performed with this approach in Spain. The donor was a 43-year-old asthmatic female diagnosed with severe hypoxic encephalopathy. She was considered a potential cDCD donor and a suitable candidate for multiorgan procurement including the heart via thoraco-abdominal normothermic regional perfusion. The heart recipient was a 60-year-old male diagnosed with amyloid cardiomyopathy. Cold ischemia time was 55 min. The surgery was uneventful.

CONCLUSIONS

This case report, the first of its kind in Spain, supports the feasibility of evaluating and successfully transplanting cDCD hearts without the need for ex-situ perfusion based on the use of thoraco-abdominal normothermic regional perfusion opening the way for multiorgan donation in cDCD.

Effect on the donor lungs of using abdominal normothermic regional perfusion in controlled donation after circulatory death

OBJECTIVES

Controlled donation after circulatory death (cDCD) donors are becoming a common source of organs for transplantation globally. However, the graft survival rate of cDCD abdominal organs is inferior to that of organs from brain-dead donors. The rapid retrieval (RR) technique is used by most donor organ procurement teams. The abdominal normothermic regional perfusion (A-NRP) technique has been implemented to minimize warm ischaemic damage to the abdominal organs. However, there is limited information on the effect of A-NRP on the quality of the donor lungs. This study aimed to compare lung transplantation outcomes using lungs procured from cDCD donors using the A-NRP and abdominal RR techniques.

METHODS

A single-centre retrospective analysis of consecutive transplant recipients of cDCD lungs from June 2013 to December 2019 was performed. The recipients were divided into 2 cohorts according to the abdominal procurement technique used. The recipient and donor characteristics (age, sex, cause of brain injury, warm ischaemic time, diagnosis, lung allocation score and other factors), incidence of primary graft dysfunction and early survival were monitored.

RESULTS

Twenty-eight consecutive lung transplantation recipients were identified (median age 59 years; 61% male); 14 recipients received lungs using the A-NRP and 14 using abdominal RR for abdominal organ retrieval. There were no significant differences in the baseline characteristics, primary graft dysfunction (P = 0.70), hospital mortality (P = 1.0) and 1-year survival rate (P = 1.0) between the 2 groups.

CONCLUSIONS

No difference was observed in lung transplantation outcomes irrespective of the abdominal organ procurement technique used (A-NRP or abdominal RR).

Hypothermic Oxygenated Perfusion Versus Normothermic Regional Perfusion in Liver Transplantation From Controlled Donation After Circulatory Death: First International Comparative Study

OBJECTIVE

To compare HOPE and NRP in liver transplantation from cDCD.

SUMMARY OF BACKGROUND DATA

Liver transplantation after cDCD is associated with higher rates of graft loss. Dynamic preservation strategies such as NRP and HOPE may offer safer use of cDCD grafts.

METHODS

Retrospective comparative cohort study assessing outcomes after cDCD liver transplantation in 1 Swiss (HOPE) and 6 French (NRP) centers. The primary endpoint was 1-year tumor-death censored graft and patient survival.

RESULTS

A total of 132 and 93 liver grafts were transplanted after NRP and HOPE, respectively. NRP grafts were procured from younger donors (50 vs 61 years, P < 0.001), with shorter functional donor warm ischemia (22 vs 31 minutes, P < 0.001) and a lower overall predicted risk for graft loss (UK-DCD-risk score 6 vs 9 points, P < 0.001). One-year tumor-death censored graft and patient survival was 93% versus 86% (P = 0.125) and 95% versus 93% (P = 0.482) after NRP and HOPE, respectively. No differences in non-anastomotic biliary strictures, primary nonfunction and hepatic artery thrombosis were observed in the total cohort and in 32 vs. 32 propensity score-matched recipients CONCLUSION:: NRP and HOPE in cDCD achieved similar post-transplant recipient and graft survival rates exceeding 85% and comparable to the benchmark values observed in standard DBD liver transplantation. Grafts in the HOPE cohort were procured from older donors and had longer warm ischemia times, and consequently achieved higher utilization rates. Therefore, randomized controlled trials with intention-to-treat analysis are needed to further compare both preservation strategies, especially for high-risk donor-recipient combinations.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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