Utilization of organs from donors after circulatory death for vascularized pancreas and islet of Langerhans transplantation: recommendations from an expert group

Donation after circulatory death (DCD) donors are increasingly being used as a source of pancreas allografts for vascularized organ and islet transplantation. We provide practice guidelines aiming to increase DCD pancreas utilization. We review risk assessment and donor selection criteria. We report suggested factors in donor and recipient clinical management and provide an overview of the activities and outcomes of vascularized pancreas and islet transplantation.

Early occurrence of new-onset diabetes after transplantation is related to type of liver graft and warm ischaemic injury

BACKGROUND & AIMS

We studied new-onset diabetes after transplantation (NODAT) in liver transplantation with grafts donated after brain death (DBD) or circulatory death (DCD), focusing on the early post-transplant period.

METHODS

A total of 430 non-diabetic primary liver transplant recipients [DCD, n = 90 (21%)] were followed up for 30 months (range 5-69). NODAT was defined as the composite endpoint of one of following: (i) Two non-fasting plasma glucose levels > 11.1 mmol/L ≥ 30 days apart, (ii) oral hypoglycaemic drugs ≥ 30 days consecutively (iii) insulin therapy ≥ 30 days and (iv) HbA1c ≥ 48 mmol/L. Resolution of NODAT was defined as cessation of treatment or hyperglycaemia.

RESULTS

Total of 81/430 (19%) patients developed NODAT. Incidence and resolution of NODAT over time showed significantly different patterns between DCD and DBD liver graft recipients; early occurrence, high peak incidence and early resolution were seen in DCD. In multivariate logistic regression including age, ethnicity, HCV, tacrolimus level and pulsed steroids, only DCD was independently associated with NODAT at day 15 post-transplant (OR 6.5, 95% CI 2.3-18.4, P < 0.001), whereas age and pulsed steroids were significant factors between 30-90 days. Combined in multivariate Cox regression model for NODAT-free survival, graft type, age and pulsed steroids were each independent predictor for decreased NODAT-free survival in the first 90-postoperative days.

CONCLUSION

Early peak of NODAT in DCD graft recipients is a novel finding, occurring independently from known risk factors. Donor warm ischaemia and impact on insulin sensitivity should be further studied and could perhaps be associated with graft function.

Preliminary results of transplantation with kidneys donated after cardiac death: a path of hope for organ transplantation in China

BACKGROUND

This article aims to explore the feasibility and effect of kidney transplantation (KT) from donation after cardiac death (DCD) donors in China.

METHODS

From July 2011 to April 2013, 94 DCD kidneys retrieved and transplanted by our centre were reviewed in this largest single-centre cohort study. Patients with and without delayed graft function (DGF) were compared between DCD KT cohorts. Estimated glomerular filtration rate (eGFR), post-operative complications and graft loss at different time points were recorded. Factors related to DGF were examined and analysed.

RESULTS

There was no primary non-function (PNF) graft observed from patients. DGF rate was 27.7%; and 1-year overall graft and patient survival rates were 95.7 and 98.9%, respectively. In the first 6 months post-transplantation, eGFR was significantly lower in the DGF group compared with the non-DGF group (46 versus 52 mL/min; P = 0.04); but the difference disappeared thereafter (50 versus 47 mL/min, after 1 year).

CONCLUSION

Despite early DGF and short-term observations, we are pleased to have this opportunity of sharing our initial experience and results, and justifying the continued DCD KT programmes in China.

Hypothermic machine perfusion of kidneys retrieved from standard and high-risk donors

Hypothermic machine perfusion (HMP) of kidneys is a long-established alternative to static cold storage and has been suggested to be a better preservation method. Today, as our deceased donor profile continues to change towards higher-risk kidneys of lower quality, we are confronted with the limits of cold storage. Interest in HMP as a preservation technique is on the rise. Furthermore, HMP also creates a window of opportunity during which to assess the viability and quality of the graft before transplantation. The technology might also provide a platform during which the graft could be actively repaired, making it particularly attractive for higher-risk kidneys. We review the current evidence on HMP in kidney transplantation and provide an outlook for the use of the technology in the years to come.

Normothermic ex vivo perfusion provides superior organ preservation and enables viability assessment of hearts from DCD donors

The shortage of donors in cardiac transplantation may be alleviated by the use of allografts from donation after circulatory death (DCD) donors. We have previously shown that hearts exposed to 30 min warm ischemic time and then flushed with Celsior supplemented with agents that activate ischemic postconditioning pathways, show complete recovery on a blood-perfused ex vivo working heart apparatus. In this study, these findings were assessed in a porcine orthotopic heart transplant model. DCD hearts were preserved with either normothermic ex vivo perfusion (NEVP) using a clinically approved device, or with standard cold storage (CS) for 4 h. Orthotopic transplantation into recipient animals was subsequently undertaken. Five of six hearts preserved with NEVP demonstrated favorable lactate profiles during NEVP and all five could be weaned off cardiopulmonary bypass posttransplant, compared with 0 of 3 hearts preserved with CS (p < 0.05, Fisher's exact test). In conclusion, DCD hearts flushed with supplemented Celsior solution and preserved with NEVP display viability before and after transplantation. Viability studies of human DCD hearts using NEVP are warranted.

Subnormothermic machine perfusion for preservation of porcine kidneys in a donation after circulatory death model

Machine perfusion for preservation led to compelling success for the outcome of renal transplantation. Further refinements of methods to decrease preservation injury remain an issue of high interest. This study investigates functional and morphological aspects of kidneys preserved by subnormothermic (20 °C) machine perfusion (SNTM) compared with oxygenated hypothermic machine perfusion (HMPox) and cold storage (CS) in a donation after circulatory death (DCD) model. After 30 min of warm ischaemia, porcine kidneys were randomly assigned to preservation for 7 h by CS, HMPox or SNTM. Afterwards, kidneys were reperfused for 2 h with autologous blood in vitro for assessment of function and integrity. Application of SNTM for preservation led to significantly higher blood flow and urine output compared with both other groups. SNTM led to a twofold increased creatinine clearance compared with HMPox and 10-fold increased creatinine clearance compared with CS. Structural integrity was best preserved by SNTM. In conclusion, this is the first study on SNTM for kidneys from DCD donors. SNTM seems to be a promising preservation method with the potential to improve functional parameters of kidneys during reperfusion.

The marginal kidney donor

PURPOSE OF REVIEW

The current era of organ shortage has necessitated a widening of criteria for donation, considering donors who would have been considered unsuitable before. This review summarizes the recent advances in strategies to maximize the use of marginal kidneys without compromising the outcomes.

RECENT FINDINGS

Various strategies have been studied and implemented to optimize procurement and allocation of marginal kidneys, and to preserve their function. In particular, a growing number of transplant centers are using donors after circulatory death. Whereas normothermic ex-vivo and postmortem perfusion are promising procedures to improve the outcomes of marginal grafts in the future, dual-kidney transplantation is a viable approach which is at present potentially underutilized. Despite active research on new strategies to evaluate organ quality, pretransplant biopsy assessment currently remains the most reliable method. The practice of using living donors with advanced age is supported by available evidence, whereas the use of young living donors with minor medical abnormalities needs further investigation.

SUMMARY

Progress has been made in the recent years, clarifying the best criteria for evaluating, recovering, and allocating marginal kidney donors. However, further research is needed, with special regards to the criteria for using marginal living-kidney donors.

Strategies to increase the donor pool and access to kidney transplantation: an international perspective

In this position article, DESCARTES (Developing Education Science and Care for Renal Transplantation in European States) board members describe the current strategies aimed at expanding living and deceased donor kidney pools. The article focuses on the recent progress in desensitization and kidney paired exchange programmes and on the expanded criteria for the use of donor kidneys and organs from donors after circulatory death. It also highlights differences in policies and practices across different regions with special regard to European Union countries. Living donor kidney paired exchange, the deceased donor Acceptable Mismatch Programme and kidneys from donors after circulatory death are probably the most promising innovations for expanding kidney transplantation in Europe over the coming decade. To maximize success, an effort is needed to standardize transplant strategies, policies and legislation across European countries.

Do we need a different organ allocation system for kidney transplants using donors after circulatory death?

BACKGROUND

There is no national policy for allocation of kidneys from Donation after circulatory death (DCD) donors in the UK. Allocation is geographical and based on individual/regional centre policies. We have evaluated the short term outcomes of paired kidneys from DCD donors subject to this allocation policy.

METHODS

Retrospective analysis of paired renal transplants from DCD's from 2002 to 2010 in London. Cold ischemia time (CIT), recipient risk factors, delayed graft function (DGF), 3 and 12 month creatinine) were compared.

RESULTS

Complete data was available on 129 paired kidneys.115 pairs were transplanted in the same centre and 14 pairs transplanted in different centres. There was a significant increase in CIT in kidneys transplanted second when both kidneys were accepted by the same centre (15.5 ± 4.1 vs 20.5 ± 5.8 hrs p<0.0001 and at different centres (15.8 ± 5.3 vs. 25.2 ± 5.5 hrs p=0.0008). DGF rates were increased in the second implant following sequential transplantation (p=0.05).

CONCLUSIONS

Paired study sequential transplantation of kidneys from DCD donors results in a significant increase in CIT for the second kidney, with an increased risk of DGF. Sequential transplantation from a DCD donor should be avoided either by the availability of resources to undertake simultaneous procedures or the allocation of kidneys to 2 separate centres.