Maximizing Utilization in Pancreas Transplantation: Phenotypic Characteristics Differentiating Aggressive From Nonaggressive Transplant Centers

Association of balanced abdominal organ transplant center volumes with patient outcomes

BACKGROUND

The volume-outcome relationship for organ-specific transplantation is well-described; it is unknown if the relative balance of kidney compared with liver volumes within an institution relates to organ-specific outcomes. We assessed the association between relative balance within a transplant center and outcomes.

METHODS

National retrospective analysis of isolated kidney and liver transplants in United States 2005-2014 followed through 2019. Latent class analysis defined transplant center phenotypes. Multivariate Cox models estimated death-censored graft loss and mortality.

RESULTS

Latent class analysis identified four phenotypes: kidney only (n = 117), kidney dominant (n = 36), mixed/balanced (n = 90), and liver dominant (n = 13). Compared to mixed centers, the risk of kidney graft loss was higher at kidney-dominant (HR 1.07, p < .001) and liver-dominant (HR 1.10, p < .001) centers, while kidney-only (HR 1.06, p = .01) centers had higher mortality. Liver graft loss was not associated with phenotype, but risk of patient death was lower (HR 0.93, p = .02) at liver dominant and higher (HR 1.06, p = .02) at kidney-dominant centers.

CONCLUSIONS

A mixed phenotype was associated with improved kidney transplant outcomes, whereas liver transplant outcomes were best at liver-dominant centers. While these findings need to be verified with center-level resources, optimization of shared resources could improve patient and organ outcomes.

Risk analysis of extended pancreas donor selection criteria

INTRODUCTION

The success of pancreas transplantation, in combination with a stable number of available allografts has resulted in an increasing waiting list. This study investigated donor potential by expanding age and Body Mass Index (BMI) criteria.

METHODS

All reported donors in the Netherlands between 2013 and 2017 were analysed. Risk assessment of extended criteria donors was done by in-depth analysis of donor reports and calculation of the Pancreas Donor Risk Index (PDRI). The PDRI of these extended criteria donors was compared to standard criteria donors to evaluate the increased risk on graft failure.

RESULTS

A total of 1273 donors were reported. Of these donors, 405 donors were reported as pancreas donor, of which 93 (23%) pancreata were transplanted. Extending age criterion with 5 years could result in additional 40 Donation after Brain Death donors and 37 Donation after Circulatory Death donors reported. In 24 (31%) extended age criteria donors the PDRI was below the upper limit of currently transplanted pancreata. Extending BMI criteria to 35 kg/m² could result in an additional 19 (6%) donors reported.

CONCLUSIONS

Extending BMI criteria could result in a slight increase of reported donors. Extending age criteria increased significantly the number of reported donors. In 24 (31%) of the older donors the PDRI showed a reduced risk compared to currently transplanted pancreata. This study suggest that, if other risk factors are absent, pancreata of extended age and/or BMI criteria donors should be considered for transplantation.

Machine Perfusion and the Pancreas: Will It Increase the Donor Pool?

PURPOSE OF REVIEW

Pancreas transplantation enables complete patient independence from exogenous insulin administration and increases both patient survival and quality of life. Despite this, there has been a decline in pancreas transplantation for the past 20 years, influenced by changing donor demographics with more high-risk extended criteria (ECD) and donation after cardiac death (DCD) donors. This review discusses whether the advent of machine perfusion (MP), if extended to the pancreas, can increase the pool of suitable donor organs.

RECENT FINDINGS

Hypothermic and normothermic MP, as forms of preservation deemed superior to cold storage for high-risk kidney and liver donor organs, have opened the avenue for translation of this work into the pancreas. Recent experimental models of porcine and human ex-vivo pancreatic MP are promising. Applications of MP to the pancreas however need refinement-focusing on perfusion protocols and viability assessment tools. Emerging research shows pancreatic MP can potentially offer superior preservation capacity, the ability to both resuscitate and manipulate organs, and assess functional and metabolic organ viability. The future of MP will lie in organ assessment and resuscitation after retrieval, where ultimately organs initially considered high risk and unsuitable for transplantation will be optimised and transformed, making them then available for clinical use, thus increasing the pool of suitably viable pancreata for transplantation.

Predictive and Comparative Study Between Clinic Consensus Document for Pancreas Acceptance and Predictive Value of Preprocurement Pancreas Allocation Suitability Score (P-PASS)

The strict selection of pancreas for transplant has forced the development of different documents to select the suitable organ in order to minimize the risks and complications of the transplant. In 2008, Eurotransplant published the Preprocurement Pancreas Allocation Suitability Score (P-PASS) for pretransplant selection. In 2001 the Hospital Clinic of Barcelona developed a Clinical Consensus Document (CCD).

OBJECTIVES

We aimed to analyze the predictive decision of the pancreas acceptance to offers received in the hospital, according to the CCD criteria and compare it with the recommended value of suitability for accepting the pancreas according to the P-PASS value.

MATERIAL AND METHODS

We performed a retrospective comparative study between the criteria of selection of the CCD for pancreas from 2016-2017 in comparison with the values obtained if the P-PASS had been used: ≤ 17, acceptance criteria and P-PASS; > 17, risk criteria. We defined the organ reported as rejected or accepted. The accepted organ could be procured and transplanted or discarded.

RESULTS

With the CCD criteria, 7 more organs were transplanted than if we only applied the potential P-PASS criteria. In contrast, P-PASS would have ruled out an additional 9% of pancreases in relation to CCD criteria.

CONCLUSIONS

According our experience, it is difficult to find an adequate prediction model to select pancreas for transplantation. The application of the DCC criteria increases the number of organs valid for transplantation. At present, new criteria should be re-evaluated within multicenter studies.