Accept or refuse? Factors influencing the decision-making of transplant surgeons who are offered a pancreas: results of a qualitative study

Quality assessment of donor liver procurement surgery using an unadjusted CUSUM prediction model. A practical nationwide evaluation

BACKGROUND

The aim of this study was to analyze the value of the unadjusted CUSUM graph of liver surgical injury and discard rates in organ procurement in the Netherlands.

METHODS

Unadjusted CUSUM graphs were plotted for surgical injury (C event) and discard rate (C2 event) from procured livers accepted for transplantation for each local procurement team compared with the total national cohort. The average incidence for each outcome was used as benchmark based on procurement quality forms (Sep 2010-Oct 2018). The data from the five Dutch procuring teams were blind-coded.

RESULTS

The C and C2 event rate were 17% and 1.9%, respectively (n = 1265). A total of 12 CUSUM charts were plotted for the national cohort and the five local teams. National CUSUM charts showed an overlapping "alarm signal." This overlapping signal for both C and C2, albeit a different time period, was only found in one local team. The other CUSUM alarm signal went off for two separate local teams, but only for C events or C2 events respectively, and at different points in time. The other remaining CUSUM charts showed no alarm signaling.

CONCLUSION

The unadjusted CUSUM chart is a simple and effective monitoring tool in following performance quality of organ procurement for liver transplantation. Both national and local recorded CUSUMs are useful to see the implication of national and local effects on organ procurement injury. Both procurement injury and organ discard are equally important in this analysis and need to be separately CUSUM charted.

A Conceptual Model for Sources of Differential Selection in Lung Transplant Allocation

Rationale: In the United States, donor lungs are allocated to transplant candidates on the basis of lung allocation scores (LAS). However, additional factors beyond the LAS can impact who is transplanted, including listing and donor-organ acceptance practices. These factors can result in differential selection, undermining the objectivity of lung allocation. Yet their impact on the lung transplant pathway has been underexplored. Objectives: We sought to systematically examine sources of differential selection in lung transplantation via qualitative methods. Methods: We conducted semistructured qualitative interviews with lung transplant surgeons and pulmonologists in the United States between June 2019 and June 2020 to understand clinician perspectives on differential selection in lung transplantation and the LAS. Results: A total of 51 respondents (30 surgeons and 21 pulmonologists) identified many sources of differential selection arising throughout the pathway from referral to transplantation. We synthesized these sources into a conceptual model with five themes: 1) transplant center's degree of risk tolerance and accountability; 2) successfulness and fairness of the LAS; 3) donor-organ availability and regional competition; 4) patient health versus program health; and 5) access to care versus responsible stewardship of organs. Conclusions: Our conceptual model demonstrates how differential selection can arise throughout lung transplantation and facilitates the further study of such selection. As new organ allocation models are developed, differential selection should be considered carefully to ensure that these models are more equitable.

The liver transplant surgeon Mondays blues: an Italian perspective

Poor data exist on the influence of holidays and weekdays on the number and the results of liver transplantation (LT) in Italy. The study's main objective is to investigate the impact of holidays and the different days of the week on the LT number and early graft survival rates in a multi-centric Italian series. We performed a retrospective analysis on 1,026 adult patients undergoing first deceased-donor transplantation between January 2004 and December 2018 in the three university centers in Rome. During the 4,504 workdays, 881 LTs were performed (85.9%; one every 5.1 days on average). On the opposite, 145 LTs were done during the 975 holidays (14.1%; one every 7.1 days on average). Fewer LTs were performed on holidays (P = 0.004). There were no substantial differences in donor-, recipient- and transplant-related characteristics in LTs performed on weekdays or holidays. On Monday, fewer transplants were performed (vs. other weekdays: P < 0.0001; vs. Sunday: P = 0.03). At multivariable Cox regression analysis, LTs performed during the holiday or during the different days of the week were not found to be independent risk factors for the risk of 3- and 12-month graft loss. At three-month survival curves, no differences were observed among the transplants performed during the holidays versus the workdays (86.2 vs. 85.0%; P-0.70). The range of graft survival rates based on the day of the week was 81.6-86.9%, without showing any significant differences (P = 0.57). Fewer transplants are performed on holidays and Mondays. Survivals are not affected by holidays or the day the transplant is performed.

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.

Deceased Brain Dead Donor Liver Transplantation and Utilization in the United States: Nighttime and Weekend Effects

BACKGROUND

Understanding factors that contribute to liver discards and nonusage is urgently needed to improve organ utilization.

METHODS

Using Scientific Registry of Transplant Recipient data, we studied a national cohort of all US adult, deceased brain dead donor, isolated livers available for transplantation from 2003 to 2016, including organ-specific and system-wide factors that may affect organ procurement and discard rates.

RESULTS

Of 73 686 available livers, 65 316 (88.64%) were recovered for transplant, of which 6454 (9.88%) were ultimately discarded. Livers that were not procured or, on recovery, discarded were more frequently from older, heavier, hepatitis B virus (HCV)+, and more comorbid donors (P < 0.001). However, even after adjustment for organ quality, the odds of liver nonusage were 11% higher on the weekend (defined as donor procurements with cross-clamping occurring from 5:00 PM Friday until 11:59 AM Sunday) compared with weekdays (P < 0.001). Nonuse rates were also higher at night (P < 0.001), defined as donor procurements with cross-clamping occurring from 5:00 PM to 5:00 AM; however, weekend nights had significantly higher nonuse rates compared with weekday nights (P = 0.005). After Share 35, weekend nonusage rates decreased from 21.77% to 19.51% but were still higher than weekday nonusage rates (P = 0.065). Weekend liver nonusage was higher in all 11 United Network of Organ Sharing regions, with an absolute average of 2.00% fewer available livers being used on the weekend compared with weekdays.

CONCLUSIONS

Although unused livers frequently have unfavorable donor characteristics, there are also systemic and operational factors, including time of day and day of the week a liver becomes available, that impact the chance of liver nonprocurement and discard.

Expanding pancreas donor pool by evaluation of unallocated organs after brain death: Study protocol clinical trial (SPIRIT Compliant)

BACKGROUND

Pancreas graft quality directly affects morbidity and mortality rates after pancreas transplantation (PTx). The criteria for pancreas graft allocation are restricted, which has decreased the number of available organs. Suitable pancreatic allografts are selected based on donor demographics, medical history, and the transplant surgeon's assessment of organ quality during procurement. Quality is assessed based on macroscopic appearance, which is biased by individual experience and personal skills. Therefore, we aim to assess the histopathological quality of unallocated pancreas organs to determine how many unallocated organs are potentially of suitable quality for PTx.

METHODS AND ANALYSIS

This is a multicenter cross-sectional explorative study. The demographic data and medical history of donor and cause of rejection of the allocation of graft will be recorded. Organs of included donors will be explanted and macroscopic features such as weight, color, size, and stiffness will be recorded by 2 independent transplant surgeons. A tissue sample of the organ will be fixed for further microscopic assessments. Histopathologic assessments will be performed as soon as a biopsy can be obtained. We will evaluate up to 100 pancreata in this study.

RESULT

This study will evaluate the histopathological quality of unallocated pancreas organs from brain-dead donors to determine how many of these unallocated organs were potentially suitable for transplantation based on a histopathologic evaluation of organ quality.

CONCLUSION

The comprehensive findings of this study could help to increase the pancreas graft pool, overcome organ shortage, reduce the waiting time, and also increase the number of PTx in the future. Registration number: ClinicalTrials.gov: NCT04127266.

Donor cardiac arrest and cardiopulmonary resuscitation: impact on outcomes after simultaneous pancreas-kidney transplantation - a retrospective study

Donor cardiac arrest and cardiopulmonary resuscitation (CACPR) has been considered critically because of concerns over hypoperfusion and mechanical trauma to the donor organs. We retrospectively analyzed 371 first simultaneous pancreas–kidney transplants performed at the Medical University of Innsbruck between 1997 and 2017. We evaluated short‐ and long‐term outcomes from recipients of organs from donors with and without a history of CACPR. A total of 63 recipients received a pancreas and kidney graft from a CACPR donor. At 1, and 5‐years, patient survival was similar with 98.3%, and 96.5% in the CACPR and 97.0%, and 90.2% in the non‐CACPR group (log rank P = 0.652). Death‐censored pancreas graft survival was superior in the CACPR group with 98.3%, and 91.4% compared to 86.3%, and 77.4% (log rank P = 0.028) in the non‐CACPR group, which remained statistically significant even after adjustment [aHR 0.49 (95% CI 0.24–0.98), P = 0.044]. Similar relative risks for postoperative complications Clavien Dindo > 3a, pancreatitis, abscess, immunologic complications, delayed pancreas graft function, and relative length of stay were observed for both groups. Donors with a history of CACPR are, in the current practice, safe for transplantation. Stringent donor selection and short CPR durations may allow for outcomes surpassing those of donors without CACPR.

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

BACKGROUND

Maximizing pancreas utilization requires a balance between judicious donor selection and transplant center aggressiveness. We sought to determine how such aggressiveness affects transplant outcomes.

METHODS

Using the Scientific Registry of Transplant Recipients, we studied 28 487 deceased-donor adult pancreas transplants. Donor and recipient demographic factors indicative of aggressiveness were used to score center aggressiveness. We compared outcomes of low (> 1 SD below mean), medium (± 1 SD from mean), and high (> 1 SD above mean) aggressiveness centers using bivariate and multivariable regressions.

RESULTS

Donor and recipient aggressiveness demonstrated a roughly linear relationship (R = 0.20). Center volume correlated moderately with donor (rs = 0.433) and recipient (rs = 0.270) aggressiveness. In bivariate analysis, there was little impact of donor selection aggressiveness on graft survival. Further, for simultaneous pancreas and kidney transplants, centers with greater recipient aggressiveness selection had better graft survival. High-volume centers had better graft survival than low-volume centers. In multivariable analysis, donor aggressiveness did not have an effect on graft survival, whereas graft survival for medium (hazard ratio [HR], 0.66, 95% confidence interval [95% CI], 0.53-0.83) and high (HR, 0.67; CI, 0.51-0.86) recipient aggressiveness performed better than low-aggressiveness centers. There was a clear volume effect, with high-volume centers (>20 transplants/year; HR, 0.69; CI, 0.61-0.79) performing better than low-volume centers.

CONCLUSIONS

Center practice patterns using higher-risk donors and recipients did not negatively affect outcomes. This effect is likely mediated through efficiencies gained with the increased transplant volumes at these centers.

Pancreas Donor Risk Index but Not Pre-Procurement Pancreas Allocation Suitability Score Predicts Pancreas Graft Survival: A Cohort Study from a Large German Pancreas Transplantation Center

Background

The pre-procurement pancreas allocation suitability score (P-PASS) was introduced to support clinical decision-making and ultimately expand the currently insufficient pancreas donor pool. The pancreas donor risk index (PDRI) can be used at the time of organ offering to predict one-year graft survival. Thus, this study aimed to analyze the validity of the PDRI and P-PASS in a large German transplant center.

Material/Methods

From 2002 to 2015, we performed 327 pancreas transplantations at our center. P-PASS and PDRI were calculated for 322 patients. To evaluate the pancreas graft survival, the patient cohort was divided into 2 P-PASS (<17, n=115 and ≥17, n=207) and 3 PDRI groups (<1, n=87; 1–1.5, n=133; and >1.5, n=102). Kaplan-Meier and Cox regression analyses were performed. We also examined differences regarding early pancreas graft failure for both scores using the chi-square test.

Results

The PDRI was associated with pancreas graft survival in the univariate analysis (p=0.023). In the multivariate analysis, a PDRI >1.5 was associated with significantly decreased graft survival (hazard ratio=1.792, 95% confidence interval=1.10–2.90, p=0.018). The P-PASS showed no significant association (p=0.081) with pancreas graft survival in the Kaplan-Meier survival analysis. There were significantly more early pancreas graft losses in the P-PASS ≥17 group (p=0.025).

Conclusions

Our results showed an association between P-PASS ≥17 and early pancreas graft failure. However, this does not apply to long-term pancreas graft survival; the PDRI proved to be a better tool for this, and PDRI values >1.5 were associated with significantly worse outcomes after pancreas transplantation.

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.

Donor Characteristics of Pancreas Transplantation in Australia and New Zealand: A Cohort Study 1984-2014

Background

The aim of this study was to audit the characteristics of pancreas donors over time in Australia and New Zealand. Pancreas transplantation was introduced in Australian and New Zealand in 1984.

Methods

We analyzed data from the Australia and New Zealand Islet and Pancreas Transplant Registry, 1984 to 2014. We investigated the variation of donor characteristics of sex, age, body mass index, smoking status, blood group, multiple organ donation, cytomegalovirus status, terminal creatinine, hypertension, and cause of death for pancreas transplantation over time. We used χ² test (Fisher test when necessary) or analysis of variance to test difference for categorical or continuous characteristics, respectively.

Results

There were 628 pancreas donors from 1984 to 2014. Donor body mass index (from 21.9 to 24.0, P < 0.001) and age (from 23.9 to 28.5, P = 0.02) have both increased while terminal creatinine has decreased (86.3 to 73.3, P = 0.01) from 1995 to 2014. In the meantime, the proportions of donors with hypertension (from 19% to 1%, P < 0.001) and who were smokers (from 54% to 15%, P < 0.001) have decreased. Profile of cause of donor death has also changed over time (P = 0.06) with increase in cerebral hypoxia/ischemia (from 3% to 17%) and reductions in intracranial hemorrhage (27% to 13%).

Conclusions

Many donor characteristics have changed over time. The most significant changes appear to reflect changes in the general population, rather than changes in donor selection.

The Value of PDRI and P-PASS as Predictors of Outcome After Pancreas Transplantation in a Large European Pancreas Transplantation Center

OBJECTIVE

In 2008, the preprocurement pancreas suitability score (P-PASS) was introduced within Eurotransplant to predict suitability of pancreas donors. A P-PASS of 17 or higher would have lower graft survival compared with pancreatic grafts from donors with a P-PASS lower than 17. In 2010, a continuous model, the pancreas donor risk index (PDRI), was designed. Before using this model in the European donor population, it has to be validated in the European setting.

METHODS

In this study, P-PASS and PDRI were validated using the results of all pancreas transplants performed at our center. The P-PASS and PDRI were compared as both continuous and dichotomous values. The original cutoff point of 17 divided P-PASS groups. Median PDRI (1.24) divided PDRI groups.

RESULTS

In total, 349 pancreas transplantations were performed. The P-PASS of 17 or higher was not associated with graft survival (P = 0.448). The PDRI of 1.24 or higher was associated with reduced graft survival in univariate analysis (P = 0.007) and multivariate analysis (P = 0.002). The PDRI concordance index was 0.69.

CONCLUSIONS

The P-PASS has no predictive value for pancreas graft survival and should not be used in clinical decision making. The PDRI is a significant predictor of pancreas graft survival but should be used carefully, because good results can be achieved with grafts from high-PDRI donors.

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.