Utilization of pediatric donors for pancreas transplantation

Donor risk factors in pancreas transplantation

The aim of the work was to analyze and expose the donor and recipient risk factors in pancreas transplantation. In the following paper, we exposed the 2018 Spanish Consensus Document on Donor and Recipient Selection Criteria for Pancreas Transplantation. An assessment of the previous Selection Criteria for Donors and Recipients of Pancreas Transplantation, published in 2005 by the Spanish Pancreas Transplant Group (GETP) and the National Transplant Organization (ONT) was performed. A literature review was performed using Cochrane Library, PubMed and Google Scholar databases. Some of the following terms were used for the literature search: “Diabetes Mellitus,” “Pancreas Transplantation,” “Insulin-Secreting Cells,” “Pancreas Allograft Thrombosis,” “Allograft Pancreatitis,” “Donors’ Risk Factors,” “Recipients’ Risk Factors,” “Pancreas Allograft Rejection” and “Pancreas Allograft Survival.” After an extended search, different inclusion criteria were established. Articles and documents with abstracts of full text and in English or Spanish language were selected. Subsequently, different scientific meetings took place during 2015 and 2016 by the GETP. Finally, the updated criteria were published by the GETP and ONT in 2018. Several risk factors have been described in pancreas transplantation that can be divided into donor risk factors: Advanced age (> 50 years); high body mass index (BMI) (> 30 kg/m²); cause of death (e.g., stroke); previous hyperglycemia; hyperamylasemia; cold ischemia time (greater than 8 or 12 h, depending on the type of donation); the use of vasopressors in the intensive care unit or cardiac arrest; and the macroscopic aspect of the pancreas allograft. The following are recipient risk factors: Advanced age (> 50 years); active smoking; high BMI (> 30 kg/m²); and peripheral artery disease or sensorimotor polyneuropathy. Based on the aforementioned parameters, different selection criteria have been established for the recipients depending on the type of pancreas transplantation. Knowledge of the risk factors for pancreas transplantation allows the establishment of reliable selection criteria for choosing donors and recipients.

The Outcomes of Pancreatic Transplantation from Pediatric Donors-A Single Institution Experience

OBJECTIVES

The aim of this study was to compare the outcomes of pancreatic transplantation from pediatric donors younger than 15 years of age to the outcomes of pancreatic transplantation from adult donors.

METHODS

Sixty patients underwent pancreatic transplantation in our facility from August 2012 to June 2019. These patients were divided into two groups according to the age of the donor: Cases in which the donor was younger than 15 years of age were classified into the PD group (n = 7), while those in which the donor was older than 15 years of age were classified into the AD group (n = 53). The outcomes of pancreas transplantation were retrospectively compared between the two groups.

RESULTS

Pancreatic graft survival did not differ between the PD and AD groups. Furthermore, there were no differences in the HbA1c and serum creatinine levels at three months, with good values maintained in both groups. The results of oral glucose tolerance tests (OGTTs) revealed that the blood glucose concentration did not differ between the two groups. However, the serum insulin concentration at 30 min after 75 g glucose loading was significantly higher in the PD group.

CONCLUSION

The outcomes of pancreatic transplantation from pediatric donors may be comparable to those of pancreatic transplantation from adult donors and the insulin secretion ability after transplantation may be better.

Pancreatic Grafts from Pediatric Donors Do Not Appear to Grow After Transplantation into Adults

Unlike pediatric kidney donors, there is no literature regarding the growth of pediatric donor pancreatic transplant grafts. Our center prospectively followed three pediatric donor grafts after transplant by measuring two dimensions of the graft at postoperative day one and then at one, two, and three months post-transplant surgery with the hypothesis that the grafted pancreas would not grow like pediatric kidney donors given the fundamental physiologic differences between these two organs. Two grafts were stable to minimally larger in size, the third case decreased in size. Interestingly, all patients had an excellent clinical response with normalization of HbA1c. Further study will be required to understand the natural history of pancreatic transplants from a pediatric donor. Volumetric assessment with magnetic resonance imaging (MRI) is proposed as the next step for better evaluation of graft size.

Short and long-term outcomes of systemic drainage to IVC: a new technique for pancreas transplantation

Ninety-eight percent of the whole pancreas does not serve the purpose of pancreatic transplantation and it is a major cause of surgical complications. Up to 30% of pancreas transplant recipients experience surgical complications and require reoperation. Graft thrombosis and pancreatitis are the most common complications of pancreas transplantation (PT). Thus, different surgical techniques have been described to overcome the surgical hurdles and reduce surgical complications. In this study, for the first time, we report short- and long-term outcomes of PT with inferior vena cava (IVC) venous drainage. Forty-five PTs (22 simultaneous pancreas and kidney [SPK] transplantations and 23 pancreas after kidney [PAK] transplantations) were performed with this technique in our center. Sixty-eight percent of the donors were imported from outside of our area after they were declined by their local transplantation center. Patient and graft survival rates were 100% at 1 year. No graft thrombosis or pancreatitis occurred with this technique. Six patients (13.3%) required reoperation (3 bleeding, 2 anastomotic leak, and 1 small bowel perforation). No patient or graft loss occurred due to surgical complications. We conclude that this technique provides fast and easy dissection of the venous drainage of the PT without the need of complete occlusion of venous outflow. Surgical complication rates were lower with this technique compared with other reported techniques.

Predictors of non-transplantation of adult donor organs--an observational study using routine data from Eurotransplant

BACKGROUND

The majority of pancreases, offered in allocation, are not transplanted. This pancreas under-utilisation is a phenomenon observed in all transplant systems in North-America and Europe. It was the aim of this study to analyse factors predictive of pancreas non-transplantation in Germany.

METHODS

Routine Eurotransplant data of 3,666 deceased German donors (from 2002-2011) were used for multivariate modelling. Socio-demographic and medical factors were considered as independent variables in logistic regression models with non-transplantation as dependent variable.

RESULTS

Male gender, advanced age, overweight/obesity, long ICU stay, a history of smoking, non-traumatic brain death, elevated levels of sodium, serum glucose, lipase/amylase and the liver not being considered for procurement were significant independent predictors of non-transplantation.

CONCLUSION

In line with previous research, advanced age, high BMI, long ICU stay and the liver not being considered for procurement were the strongest predictors of pancreas non-transplantation in Germany. About three quarters of the variance remained unexplained, suggesting that factors not assessed or unknown may play a decisive role.

Retrieval of the pancreas allograft for whole-organ transplantation

Proper pancreas retrieval during multi-organ recovery is one of the cornerstones of technically successful whole-organ pancreas transplantation. With evolving surgical approaches for organ retrieval and implantation, it has become standard to procure the pancreas in conjunction with other abdominal organs without compromising either vasculature, graft quality, or transplant outcomes. This review summarizes the major steps required for proper whole-organ retrieval of the pancreas allograft with suggestions and tips whenever alternative approaches are available.

[Role of simultaneous pancreas-kidney transplantation in the treatment of diabetes mellitus]

The life expectancy of patients with type 1 diabetes mellitus is inferior to that of patients with some malignancies. Simultaneous pancreas-kidney transplantation is the procedure providing the best survival results among all options of renal replacement therapy. The operative techniques and immunosuppresion have been standardized in the last decade. Although the number of transplantable organs falls behind the need, simultaneous pancreas-kidney transplantation is the method of choice for the eligible patients. The results of the two Hungarian simultaneous pancreas-kidney transplantation programs are in accordance with data published in the international literature.

Outcomes of simultaneous pancreas-kidney transplantation from brain-dead and controlled circulatory death donors

BACKGROUND

Organ scarcity has prompted increased use of organs from donation after circulatory death (DCD) donors. An early single-centre experience of simultaneous pancreas-kidney (SPK) transplantation from controlled DCD donors is described here.

METHODS

Outcomes of SPK transplants from DCD and donation after brain death (DBD) donors between August 2008 and January 2011 were reviewed retrospectively.

RESULTS

SPK transplants from 20 DCD and 40 DBD donors were carried out. Donor and recipient characteristics were similar for both groups, although pancreas cold ischaemia times were shorter in DCD recipients: median (range) 8·2 (5·9-10·5) versus 9·5 (3·8-12·5) h respectively (P = 0·004). Median time from treatment withdrawal to cold perfusion was 24 (range 16-110) min for DCD donors. There were no episodes of delayed pancreatic graft function in either group; the graft thrombosis rates were both 5 per cent. Similarly, there were no differences in haemoglobin A1c level at 12 months: median (range) 5·4 (4·9-7·7) per cent in DCD group versus 5·4 (4·1-6·2) per cent in DBD group (P = 0·910). Pancreas graft survival rates were not significantly different, with Kaplan-Meier 1-year survival estimates of 84 and 95 per cent respectively (P = 0·181).

CONCLUSION

DCD SPK grafts had comparable short-term outcomes to DBD grafts, even when procured from selected donors with a prolonged agonal phase.

A mathematical model for shortening waiting time in pancreas-kidney transplantation

AIM: To simulate a hypothetical increase of 50% in the number of pancreas-kidney (PK) transplantations using less-than-ideal donors by a mathematical model.

METHODS: We projected the size of the waiting list by taking into account the incidence of new patients per year, the number of PK transplantations carried out in the year and the number of patients who died on the waiting list or were removed from the list for other reasons. These variables were treated using a model developed elsewhere.

RESULTS: We found that the waiting list demand will meet the number of PK transplantation by the year 2022.

CONCLUSION: In future years, it is perfectly possible to minimize the waiting list time for pancreas transplantation through expansion of the donor pool using less-than-ideal donors.

A new vascular approach to the modified multivisceral graft procurement

Modified multivisceral (MMV) transplantation including the stomach, pancreaticoduodenal complex and intestine requires preservation of the left gastric and splenic arteries. The previously described techniques require division of the hepatic artery proximal to the gastroduodenal artery leaving the liver transplant team with a very short and small caliber vessel. To increase MMV graft availability and provide the liver transplant team with an appropriate quality vessel, we developed the following technique. We also describe two cases where we used this method to support the technical feasibility of this procedure.

Surgical techniques for pancreas transplantation

PURPOSE OF REVIEW

Pancreas transplantation reproducibly induces insulin independence in beta-cell penic diabetic patients. The difference between full insulin independence, partial graft function, and graft loss, mostly results from technical failure, graft rejection, and patient death with function graft. The purpose of this review is to examine recent surgical advances and discuss their contribution to improved graft function.

RECENT FINDINGS

Few actual surgical innovations were described in the period reviewed. Duodenoduodenostomy is an interesting option for drainage of digestive secretions, when the pancreas is placed behind the right colon and is oriented cephalad. The main advantage of this technique is easy endoscopic assessment of donor duodenum but, when allograft pancreatectomy is necessary, repair of native duodenum may be troublesome. Selective revascularization of the gastroduodenal artery, at the back-table, possibly improves blood supply to the head of the pancreas graft and duodenal segment. There is no proof that this additional maneuver is always beneficial, although it can be graft saving in case of poor segmental graft perfusion.

SUMMARY

Transplant surgeons should be familiar with all techniques for pancreas transplantation. Long-term graft function is possible only after technically successful pancreas transplantation. There is clearly a need for more objective assessment and standardization of surgical techniques for pancreas transplantation.

Patient and graft survival implications of simultaneous pancreas kidney transplantation from old donors

We investigated graft and patient survival implications of simultaneous pancreas kidney (SPK) transplant from old donors. Data describing patients with type 1 diabetes mellitus listed for an SPK transplant from 1994 to 2005 were drawn from Organ Procurement and Transplant Network registries. Allograft survival, patient survival and long-term survival expectations among SPK recipients from young (age <45 years) and old (age >/=45 years) donors were modeled by multivariate regression. We also examined predictors of reduced early access to young donor transplants. Of 16 496 eligible SPK candidates, 8850 patients (53.6%) received an SPK transplant and 776 (8.8%) of these transplants were from old donors. Reasonable 5-year, death-censored kidney (77.8 %) and pancreas (71.3%) survivals were achieved with old donors. SPK transplantation from both young and old donors predicted lower mortality compared to continued waiting. An additional expected wait of 1.5 years for a young donor equalized long-term survival expectations to that achieved with use of old donors. Early allocation of young donor transplants declined in the more recent era and varied by region, candidate age, blood type and sensitization. We conclude that old SPK donors should be considered for patients with decreased access to young donor transplants. Prospective evaluation of this practice is needed.

Outcomes of pancreas transplantation in the United States using cardiac-death donors

Organs donated after cardiac death (DCD) are used to expand the donor pool. We analyzed the outcomes in the United States of pancreatic transplantation of organs from DCD donors performed between 1993 and 2003. We used the OPTN/UNOS Registry to compare outcomes of primary pancreas allografts from DCD donors and donors after brain death (DBD). The primary endpoints were graft failure and patient death. A national survey regarding the use of DCD donors in pancreas transplantation was conducted among the directors of pancreas transplant centers. Data were obtained on 47 simultaneous pancreas-kidney transplants (SPK) and 10 solitary pancreas transplants from DCD donors and on 2431 SPK and 1607 solitary pancreas transplants from DBD donors. Recipients of a SPK transplants from DCD and DBD donors had equivalent patient and graft survival rates at 1, 3 and 5 years. For recipients of SPK transplants, the wait for organs from DCD donors was significantly shorter than that for organs from DBD donors. SPK recipients of organs from DCD donors had longer hospital stays than did recipients of organs from DBD donors. With renal allografts, the incidence of delayed graft function was almost four times higher with organs from DCD donors than with organs from DBD donors. Selective use of organs from DCD donors is safe for pancreas transplantation.

Simultaneous pancreas-kidney transplantation from donation after cardiac death: successful long-term outcomes

OBJECTIVE

The outcomes of simultaneous pancreas-kidney (SPK) transplantation with donor organs procured from donation after cardiac death (DCD) are compared with transplants performed with donor organs recovered from donation after brain death (DBD).

SUMMARY BACKGROUND DATA

Concerns exist regarding the utilization of pancreata obtained from DCD donors. While it is known that DCD kidneys will have a higher rate of DGF, long-term functional graft survival data for DCD pancreata have not been reported.

METHODS

A retrospective review of all DCD SPK transplants performed at a single center was undertaken.

RESULTS

Patient, pancreas, and kidney survival at 5 years were similar between DCD and DBD organs. Pancreas function and outcomes were indistinguishable between the 2 modes of procurement. As expected, the DCD kidneys had an elevated rate of DGF, which had no significant long-term clinical impact.

CONCLUSION

SPK transplantation using selected DCD donors is a safe and viable method to expand the organ pool for transplantation.

Superior long-term results of simultaneous pancreas-kidney transplantation from pediatric donors

The shortage of cadaveric donors for simultaneous pancreas-kidney transplantation has prompted the use of cadaveric organs from pediatric donors. The long-term outcome and its impact on overall long-term survival are unknown. A total of 680 recipients receiving cadaver Simultaneous pancreas-kidney (SPK) transplantation from pediatric and adult donors between July 1986 and September 2001 were analyzed and compared. Ten-year kidney and pancreas graft survival for SPK transplantation from donors aged <18 years (n = 142) were 80% and 72%, respectively, compared to 61% pancreas and kidney graft survival from donors > or =18 years of age (n = 538; p = 0.03 and 0.05, respectively). Five years post-transplant, blood glucose, HbA1c and creatinine clearance were significantly better in recipients from pediatric donors (85.3 +/- 13 mg/dL, 5.5 +/- 3.5% and 65.6 +/- 16 mL/min, respectively), compared to recipients from adult donors (95.1 +/- 29 mg/dL, 5.9 +/- 3.5% and 58.3 +/- 17 mL/min; p = 0.001, 0.01 and 0.002, respectively). Causes of graft failure for kidney and pancreas transplants were similar between the two groups. No statistically significant difference was observed in patient survival between recipients from pediatric donors compared to adult donors (85% vs. 76%, p = 0.29). When recipients of SPK from pediatric donors were stratified according to age (3-11 years and 12-17 years) and compared, no difference in kidney or pancreas graft survival was observed (kidney 76.4% vs. 81.3%, p = 0.15; pancreas 75% vs. 76%, p = 0.10, respectively). Pediatric donors represent a valuable source of organs, providing excellent short- and long-term outcomes. Wide utilization of pediatric organs will substantially increase the donor pool.

Pediatric en bloc dual kidney-pancreas transplantation into an adult recipient: a simplified technique. Benefits of the en bloc kidney-pancreas transplantation technique in pediatric donors

The lower age limit for pancreas donors is not well defined. Fear of inadequate islet beta-cell mass and of technical complications has hampered the use of pediatric donors. A surgical technique of 'en bloc' kidney-pancreas is described. Both kidneys and pancreas were removed en bloc from a 13-kg, 31-month-old child. During bench preparation, one anastomosis was performed between the portal vein and the inferior vena cava. The proximal end of the aorta was closed. The bloc was transplanted into a 36-year-old type I diabetic patient intraperitoneally in the right iliac fossa. The kidneys functioned immediately. Pancreatic graft function resumed after POD 15 but insulin therapy was maintained until POD 112. Currently, the patient retains excellent kidney and pancreas graft functions. Very young donors can be accepted as pancreas donors for adult recipients, although slow recovery of pancreatic function can be expected. Use of the en bloc technique is well suited for very small children, as it prevents potential vascular complications.

Underutilization of pancreas donors

BACKGROUND

Transplantation of the pancreas has become the treatment of choice for selected patients with type 1 diabetes mellitus. With the current shortage of cadaver donors and the increasing number of diabetic patients on the transplant waiting list, there is a critical need to optimally use all available pancreas grafts for transplantation. We have therefore explored the use of traditionally "less-than-ideal" pancreas donors, including pediatric (4-10 years), older (>or=45 years), obese (weight >or=200 lb), and non-heart-beating donors and donors with an elevated amylase (75% greater than normal values).

METHODS

A total of 620 primary simultaneous pancreas-kidney transplantations were performed at our center. We analyzed the ratio of livers to pancreata transplanted at our center and compared this to the United Network for Organ Sharing database. Using univariate and multivariate analyses, we then assessed the impact of these less-than-ideal donors on patient survival, graft survival, and postsurgical complications after simultaneous pancreas-kidney transplantation.

RESULTS

A substantial nationwide underutilization of pancreata from donor procurements is demonstrated in the United Network for Organ Sharing database. By using these less-than-ideal donors, the ratio of liver to pancreata procured can be reduced to 1.25:1. Graft survival was not significantly different in patients receiving transplants from obese, non-heart-beating, pediatric, or hyperamylasemic donors compared with grafts from ideal donors. However, grafts from donors 45 years of age or older had significantly lower 1- and 5-year graft survival rates (76% and 65% vs. 90% and 80%, P=0.006).

CONCLUSIONS

This study demonstrates that utilization of pancreas grafts from selected, less-than-ideal donors results in good overall outcomes and could potentially expand the organ donor pool.

Lessons learned from more than 1,000 pancreas transplants at a single institution

OBJECTIVE

To determine outcome in diabetic pancreas transplant recipients according to risk factors and the surgical techniques and immunosuppressive protocols that evolved during a 33-year period at a single institution.

SUMMARY BACKGROUND DATA

Insulin-dependent diabetes mellitus is associated with a high incidence of management problems and secondary complications. Clinical pancreas transplantation began at the University of Minnesota in 1966, initially with a high failure rate, but outcome improved in parallel with other organ transplants. The authors retrospectively analyzed the factors associated with the increased success rate of pancreas transplants.

METHODS

From December 16, 1966, to March 31, 2000, the authors performed 1,194 pancreas transplants (111 from living donors; 191 retransplants): 498 simultaneous pancreas-kidney (SPK) and 1 simultaneous pancreas-liver transplant; 404 pancreas after kidney (PAK) transplants; and 291 pancreas transplants alone (PTA). The analyses were divided into five eras: era 0, 1966 to 1973 (n = 14), historical; era 1, 1978 to 1986 (n = 148), transition to cyclosporine for immunosuppression, multiple duct management techniques, and only solitary (PAK and PTA) transplants; era 2, 1986 to 1994 (n = 461), all categories (SPK, PAK, and PTA), predominantly bladder drainage for graft duct management, and primarily triple therapy (cyclosporine, azathioprine, and prednisone) for maintenance immunosuppression; era 3, 1994 to 1998 (n = 286), tacrolimus and mycophenolate mofetil used; and era 4, 1998 to 2000 (n = 275), use of daclizumab for induction immunosuppression, primarily enteric drainage for SPK transplants, pretransplant immunosuppression in candidates awaiting PTA.

RESULTS

Patient and primary cadaver pancreas graft functional (insulin-independence) survival rates at 1 year by category and era were as follows: SPK, era 2 (n = 214) versus eras 3 and 4 combined (n = 212), 85% and 64% versus 92% and 79%, respectively; PAK, era 1 (n = 36) versus 2 (n = 61) versus 3 (n = 84) versus 4 (n = 92), 86% and 17%, 98% and 59%, 98% and 76%, and 98% and 81%, respectively; in PTA, era 1 (n = 36) versus 2 (n = 72) versus 3 (n = 30) versus 4 (n = 40), 77% and 31%, 99% and 50%, 90% and 67%, and 100% and 88%, respectively. In eras 3 and 4 combined for primary cadaver SPK transplants, pancreas graft survival rates were significantly higher with bladder drainage (n = 136) than enteric drainage (n = 70), 82% versus 74% at 1 year (P =.03). Increasing recipient age had an adverse effect on outcome only in SPK recipients. Vascular disease was common (in eras 3 and 4, 27% of SPK recipients had a pretransplant myocardial infarction and 40% had a coronary artery bypass); those with no vascular disease had significantly higher patient and graft survival rates in the SPK and PAK categories. Living donor segmental pancreas transplants were associated with higher technically successful graft survival rates in each era, predominately solitary (PAK and PTA) in eras 1 and 2 and SPK in eras 3 and 4. Diabetic secondary complications were ameliorated in some recipients, and quality of life studies showed significant gains after the transplant in all recipient categories.

CONCLUSIONS

Patient and graft survival rates have significantly improved over time as surgical techniques and immunosuppressive protocols have evolved. Eventually, islet transplants will replace pancreas transplants for suitable candidates, but currently pancreas transplants can be applied and should be an option at all stages of diabetes. Early transplants are preferable for labile diabetes, but even patients with advanced complications can benefit.