A registry analysis of damage to the deceased donor pancreas during procurement

British Transplantation Society guidelines on abdominal organ transplantation from deceased donors after circulatory death

The British Transplantation Society (BTS) 'Guideline on transplantation from deceased donors after circulatory death' has recently been updated and this manuscript summarises the relevant recommendations in abdominal organ transplantation from Donation after Circulatory Death (DCD) donors, encompassing the chapters on liver, kidney, pancreas and islet cell transplantation.

Whole-Organ Pancreas and Islets Transplantations in UK: An Overview and Future Directions

Whole-organ pancreas and islets transplantations are two therapeutic options to treat type 1 diabetic patients resistant to optimised medical treatment in whom severe complications develop. Selection of the best option for β-cell replacement depends on several factors such as kidney function, patient comorbidities, and treatment goals. For a patient with end-stage kidney disease, the treatment of choice is often a simultaneous transplant of the pancreas and kidney (SPK). However, it remains a major surgical procedure in patients with multiple comorbidities and therefore it is important to select those who will benefit from it. Additionally, in view of the organ shortage, new strategies to improve outcomes and reduce immune reactions have been developed, including dynamic organ perfusion technologies, pancreas bioengineering, and stem cell therapies. The purpose of this article is to review the indications, surgical techniques, outcomes, and future directions of whole-organ pancreas and islets transplantations.

Effect of donor pancreas extraction time on pancreas transplantation-a Swiss tertiary center experience

We aimed to assess the effect of donor pancreas extraction time (ET) on postoperative complications and graft function after pancreas transplantation (PT). We analyzed all consecutive donor pancreas procurements for the simultaneous pancreas and kidney transplantation (SPK) and the associated PT in a Swiss transplant center over a 20-year period. Pancreas ET was defined as the time from cold flush to static storage of the pancreas on ice. The primary endpoint was the effect of extraction time on surgical complications. Secondary endpoints comprised the effect of ET on graft function (insulin-free survival) and graft pancreatitis. Of 115 procured pancreas grafts the median donor pancreas ET was 65 min (IQR: 48-78 min). In multivariable analysis, ET did not negatively affect major complications (OR 1.41 [95% CI: .59-3.36]; p = .438) and insulin-free survival (HR 1.42 [95% CI: .55-3.63]; p = .459). The median CIT was 522 (441-608) min. CIT was associated with major complications (OR 2.51 [95% CI: 1.11-5.68]; p = .027), but without impact on insulin-free survival (HR 1.94 [95% CI: .84-4.48]; p = .119). Patients with and without graft pancreatitis had no statistically significant differences in ET and CIT (p = .164 and p = .47, respectively). In multivariable analysis, Amylase levels > 270 U/L on postoperative day 1 were significantly associated with major complications (OR 3.61 [95% CI: 1.06-12.32]; p = .040). Our results suggest that although no effect of ET on complications and graft function after PT was found, shorter CIT and less graft pancreatitis can have a positive impact on surgical complications. Results could possibly be influenced by the exceptional quality of the pancreas donors, with short travel distances and preservation times in Switzerland.

Pancreas utilization rates in the UK - an 11-year analysis

Utilization of pancreases for transplantation remains inferior to that of other organs. Herein, we analysed UK pancreas discards to identify the reasons for the low utilization rates. Data on all pancreases offered first for solid organ transplantation between 1st January 2005 and 31st December 2015 were extracted from the UK Transplant Registry. The number of organs discarded, reasons and the time point of discard were analysed. A centre specific comparison was also undertaken. 7367 pancreases were offered first for solid organ transplantation. 35% were donors after circulatory death (DCD). 3668 (49.7%) organs were not retrieved. Of the 3699 pancreases retrieved, 38% were initially accepted but subsequently discarded. 2145 (29%) grafts offered were transplanted as simultaneous pancreas-kidney or solitary pancreas. 1177 (55%) were transplanted on the first offer whilst the remaining 968 were transplanted after a median of three offers. 52% DBD pancreases were accepted and transplanted on the first offer compared with 68% DCD grafts. There were significant differences in discard rates between centres (30-80% for DBD and 3-78% for DCD, P < 0.001). A significant number of solid pancreases are discarded. Better graft assessment at retrieval could minimize unnecessary organ travel and discards. Closer links with islet programmes may allow for better utilization of discarded grafts.

Pancreas transplants from small donors: are the outcomes acceptable? A retrospective study

Despite good organ quality, pancreata from extremely small pediatric donors (<30 kg) are generally avoided by many centers because of concerns of reduced islet cell mass and early technical failure. Therefore, we sought to compare the outcomes of small pancreas grafts (<30 kg) to those from higher weight donors from transplants performed between 1994 and 2015 (n = 1183). A total of 33 pancreata were from donors' ≤30 kg (3%), with a mean weight of 23.8 kg and mean age of 7.8 years. Patient survival was similar at 1, 5, and 10 years between recipients of ≤30 and >30 kg donors (≤30 kg: 96.8%, 86.8%, and 78.1% vs. >30 kg: 96.8%, 89.5%, and 79.1%, P = 0.5). Pancreas graft survival at 1, 5, and 10 years was also similar, ≤30 kg: 93.9%, 73.2%, and 61.0% vs. >30 kg: 87%, 73.3%, and 58.3% (P = 0.7). This graft survival pattern was also seen when comparing pancreata from ≤20 kg donors to those from >20 to 30 kg. Cause of graft loss, and metabolic and physiologic outcomes did not differ between the groups. After assessing the impact of donor weight as a continuous variable and calculating recipient-to-donor weight ratio (RDWR), we observed no effect of donor weight on patient and graft outcomes.

Influence of the procurement surgeon on transplanted abdominal organ outcomes: An SRTR analysis to evaluate regional organ procurement collaboration

Single-center studies have demonstrated regional organ procurement collaboration to reduce travel redundancy and improve procurement efficiency. We studied deceased donor kidney, liver, and pancreas transplants performed in the United States between 2002 and 2014 using the Scientific Registry of Transplant Recipients (SRTR). We compared graft failure (GF), death-censored graft failure (DCGF), and patient death (PD) between organs procured by surgeons from the recipient's center (transplant procurement team [TPT]) versus surgeons from a different center (NTPT). Primary nonfunction (PNF) was assessed for liver and kidney and delayed graft function (DGF) for kidney using mixed-effects logistic modeling. There were 64 906 liver (61.6% TPT), 118 152 kidney (26.1% TPT), 10 832 simultaneous pancreas kidney (SPK; 56.6% TPT), and 4378 solitary pancreas (SP; 34.0% TPT) transplants. When compared to NTPT, DCGF for organs procured by TPT was significantly less for liver (adjusted HR: 0.93; 95% CI: 0.88-0.98) and marginally significant for kidney (0.97; 0.93-1.00) and SPK (0.90; 0.82-1.00), and not significant for SP (0.98; 0.86 -1.11). DGF for TPT kidney was significantly lower (adjusted OR 0.91; 0.87-0.95). Albeit modest, our findings demonstrate a difference between locally procured organs and those procured by the implanting team. Elucidating the etiology of these differences will enhance regional organ procurement collaboration.

Rotational culture and integration with amniotic stem cells reduce porcine islet immunoreactivity in vitro and slow xeno-rejection in a murine model of islet transplantation

BACKGROUND

Pre-transplant modification of porcine islets may improve their suitability for clinical use in diabetes management by supporting graft function and reducing the potential for xeno-rejection. The present study investigates intra-graft incorporation of stem cells that secrete beta (β)-cell trophic and immunomodulatory factors to preserve function and alter immune cell responsiveness to porcine islets.

METHODS

Isolated porcine islets were maintained in a three-dimensional rotational cell culture system (RCCS) to facilitate aggregation with human amniotic epithelial cells (AECs). Assembled islet constructs were assessed for functional integrity and ability to avoid xeno-recognition by CD4+ T-cells using mixed islet:lymphocyte reaction assays. To determine whether stem cell-mediated modification of porcine islets provided a survival advantage over native islets, structural integrity was examined in a pig-to-mouse islet transplant model.

RESULTS

Rotational cell culture system supported the formation of porcine islet:AEC aggregates with improved insulin-secretory capacity compared to unmodified islets, whilst the xeno-response of purified CD4+ T-cells to AEC-bearing grafts was significantly (P < 0.05) attenuated. Transplanted AEC-bearing grafts demonstrated slower rejection in immune-competent recipients compared to unmodified islets.

CONCLUSIONS/INTERPRETATION

Rotational culture enables pre-transplant modification of porcine islets by integration with immunomodulatory stem cells capable of subduing xeno-reactivity to CD4+ T-cells. This reduces islet rejection and offers translational potential to widen availability and improve the clinical effectiveness of islet transplantation.

Solid pancreas transplant: Pushing forward

Pancreas transplant has evolved significantly in recent years. It has now become a viable treatment option on type 1 diabetic patients with poorly controlled diabetes on conventional treatment, insulin intolerance, hypoglycaemia unawareness, brittle diabetes and/ or end-stage kidney disease. The purpose of this review is to provide an overview of pancreas transplant historical origins and current barriers to broader utilization of pancreata for transplant, with a focus on areas for future improvement to better pancreas transplant care. Donor pancreata remain underutilized; pancreatic allograft discard rates remain close to 30% in the United States. Donations after cardiac death (DCD) pancreata are seldom procured. Study groups from Europe and the United Kingdom showed that procurement professionalization and standardization of technique, as well as development of independent regional procurement teams might increase organ procurement efficiency, decrease discards and increase pancreatic allograft utilization. Pancreas transplant programs should consider exploring pancreas procurement opportunities on DCD and obese donors. Selected type 2 diabetics should be considered for pancreas transplant. Longer follow-up studies need to be performed in order to ascertain the long-term cardiovascular and quality of life benefits following pancreas transplant; the outcomes of which might eventually spearhead advocacy towards broader application of pancreas transplant among diabetics.

Surgical quality in organ procurement during day and night: an analysis of quality forms

OBJECTIVES

To analyse a potential association between surgical quality and time of day.

DESIGN

A retrospective analysis of complete sets of quality forms filled out by the procuring and accepting surgeon on organs from deceased donors.

SETTING

Procurement procedures in the Netherlands are organised per region. All procedures are performed by an independent, dedicated procurement team that is associated with an academic medical centre in the region.

PARTICIPANTS

In 18 months' time, 771 organs were accepted and procured in The Netherlands. Of these, 17 organs were declined before transport and therefore excluded. For the remaining 754 organs, 591 (78%) sets of forms were completed (procurement and transplantation). Baseline characteristics were comparable in both daytime and evening/night-time with the exception of height (p=0.003).

PRIMARY OUTCOME MEASURE

All complete sets of quality forms were retrospectively analysed for the primary outcome, procurement-related surgical injury. Organs were categorised based on the starting time of the procurement in either daytime (8:00-17:00) or evening/night-time (17:00-8:00).

RESULTS

Out of 591 procured organs, 129 organs (22%) were procured during daytime and 462 organs (78%) during evening/night-time. The incidence of surgical injury was significantly lower during daytime; 22 organs (17%) compared with 126 organs (27%) procured during evening/night-time (p=0.016). This association persists when adjusted for confounders.

CONCLUSIONS

This study shows an increased incidence of procurement-related surgical injury in evening/night-time procedures as compared with daytime. Time of day might (in)directly influence surgical performance and should be considered a potential risk factor for injury in organ procurement procedures.

Donors after circulatory death pancreas transplantation

PURPOSE OF REVIEW

The use of organs from donors after circulatory death (DCD) has become standard practice in solid organ transplantation of most abdominal organs and has been used successfully in some centres for pancreas transplantation. Nevertheless, concerns regarding poor graft outcomes and complications remain. This review aims to discuss the current state of DCD pancreas transplantation and the associated outcomes.

RECENT FINDINGS

In many countries, whereas the number of donors after brainstem death (DBD) remains stable, the mean age and BMI have increased making these donors, previously considered to be low risk, now more marginal. Recent meta-analyses have confirmed previous single-centre and registry reports that graft and patient survival after DCD pancreas transplantation are comparable with outcomes using pancreases from DBD donors; DCD pancreas transplantation is now common practice in several countries in Europe, particularly the United Kingdom. Although there have been reports of higher thrombosis rates after DCD pancreas transplantation, the significance of this is difficult to judge as the impact has not been seen in overall graft survival.

SUMMARY

Pancreas transplantation using DCD organs is well tolerated and feasible when other risk factors are minimized. Although there has been some evidence of an increased risk of thrombosis, this has not translated into a significant difference in graft survival.

Abdominal organ procurement in the Netherlands - an analysis of quality and clinical impact

Between March 2012 and August 2013, 591 quality forms were filled out for abdominal organs in the Netherlands. In 133 cases (23%), there was a discrepancy between the evaluation from the procuring and transplanting surgeons. Injuries were seen in 148 (25%) organs of which 12 (2%) led to discarding of the organ: one of 133 (0.8%) livers, five of 38 (13%) pancreata and six of 420 (1.4%) kidneys (P < 0.001). Higher donor BMI was a risk factor for procurement-related injury in all organs (OR: 1.06, P = 0.011) and donor after cardiac death (DCD) donation in liver procurement (OR: 2.31, P = 0.034). DCD donation is also associated with more pancreata being discarded due to injury (OR: 10.333, P = 0.046). A higher procurement volume in a centre was associated with less injury in pancreata (OR = -0.95, P = 0.013) and kidneys (OR = -0.91, P = 0.012). The quality form system efficiently monitors the quality of organ procurement. Although there is a relatively high rate of organ injury, the discard rate is low and it does not significantly affect 1-year graft survival for any organ. We identified higher BMI as a risk factor for injury in abdominal organs and DCD as a risk factor in livers. A higher procurement volume is associated with fewer injuries.

Professionalization of surgical abdominal organ recovery leading to an increase in pancreatic allografts accepted for transplantation in the Netherlands: a serial analysis

Professional abdominal organ recovery with certification has been mandatory in the Netherlands since 2010. This study analyses the effects of certification (January 2010-September 2015) on pancreas transplantation and compares it to an era before certification (February 2002-May 2008) for surgical injuries and the number of pancreases transplanted. A total of 264 cases were analysed. Eighty-four recovered pancreases (31.8%) with surgically injuries were encountered. Forty-six of those were surgically salvaged for transplantation, resulting in a total of 226 (85.6%) being transplanted. It was found that certified surgeons recovered grafts from older donors (36.8 vs. 33.3; P = 0.021), more often from donation after circulatory death (DCD) donors (18% vs. 0%; P < 0.001) and had less surgical injuries (21.6% vs. 41.0%; P < 0.001). Certification (OR: 0.285; P < 0.001) and surgeons from a pancreas transplant centre (OR: 0.420; P = 0.002) were independent risk factors for surgical organ injury. Predictors for proceeding to the actual pancreas transplantation were a recovering surgeon from a pancreas transplantation centre (OR: 3.230; P = 0.003), certification (OR: 3.750; P = 0.004), donation after brain death (DBD) (OR: 8.313; P = 0.002) and donor body mass index (BMI) (OR: 0.851; P = 0.023). It is concluded that certification in abdominal organ recovery will limit the number of surgical injuries in pancreas grafts which will translate in more pancreases available for transplantation.

High alcohol intake in deceased donors has no effect on pancreas graft survival: a registry analysis

Outcomes of pancreas transplantation from donors with high alcohol consumption are poorly described. The UK Transplant Registry was used to determine whether donor alcohol intake influenced pancreas survival in simultaneous pancreas-kidney (SPK) transplants performed between 2006 and 2012 (n = 770). Recipients were stratified by donor alcohol intake: group I (n = 122)-high recent alcohol intake (>21 or >14 units of alcohol/week in males or females, respectively) or previous alcohol abuse and group II (n = 648)-low/unknown current intake and no previous alcohol abuse. Median current alcohol intake was higher in group I than group II: 36.3 vs. 10 units/week; P < 0.001. One- and five-year pancreas graft survivals were 88.5% and 73.6% in group I, and 87% and 74.9% in group II. There was no difference in unadjusted graft survival between groups I and II (P = 0.76), and no difference between group II and a subgroup of group I with a donor history of alcohol abuse and high current intake (P = 0.26), or from donors with current alcohol consumption of >50 units/week (P = 0.41). Pancreas donors with past alcohol abuse or current high intake are common, and graft outcomes appear to be acceptable. This analysis suggests that high donor alcohol intake, by itself, should not exclude consideration of pancreas transplantation.

Pancreas Transplantation: An Alarming Crisis in Confidence

In the past decade, the annual number of pancreas transplantations performed in the United States has steadily declined. From 2004 to 2011, the overall number of simultaneous pancreas-kidney (SPK) transplantations in the United States declined by 10%, whereas the decreases in pancreas after kidney (PAK) and pancreas transplant alone (PTA) procedures were 55% and 34%, respectively. Paradoxically, this has occurred in the setting of improvements in graft and patient survival outcomes and transplanting higher-risk patients. Only 11 centers in the United States currently perform ≥20 pancreas transplantations per year, and most centers perform <5 pancreas transplantations annually; many do not perform PAKs or PTAs. This national trend in decreasing numbers of pancreas transplantations is related to a number of factors including lack of a primary referral source, improvements in diabetes care and management, changing donor and recipient considerations, inadequate training opportunities, and increasing risk aversion because of regulatory scrutiny. A national initiative is needed to "reinvigorate" SPK and PAK procedures as preferred transplantation options for appropriately selected uremic patients taking insulin regardless of C-peptide levels or "type" of diabetes. Moreover, many patients may benefit from PTAs because all categories of pancreas transplantation are not only life enhancing but also life extending procedures.

Necessities for a Clinical Islet Program

For more than two decades we have been refining advances in islet cell transplantation as a clinical therapy for patients suffering from type 1 diabetes. A great deal of effort has gone to making this a viable therapy for a broader range of patients with type 1 diabetes. Clinical results have progressively improved, demonstrating clinical outcomes on par with other organ transplants, specifically in terms of insulin independence, graft and patient survival. We are now at the point where islet cell transplantation, in the form of allotransplantation, has become accepted as a clinical therapy in adult patients affected by type 1 diabetes, in particular those suffering from severe hypoglycaemic unawareness. This chapter provides an overview on how this has been undertaken over the years to provide outcomes on par with other organ transplantation results. In particular this chapter focuses on the processes and facilities that are required to establish a clinical islet isolation and transplantation program. It also outlines the very important underpinning processes of selection of the organ donor for islet isolation, the processes of organ donor operation and preservation of the pancreas by various means and the ideal ways to best improve outcomes for human islet cell isolation. Providing these more optimal conditions we can underpin the isolation processes to provide islets for transplantation and as such a safe, effective and feasible therapeutic option for an increasing number of patients suffering from type 1 diabetes with severe hypoglycaemic unawareness.