Renal Graft Function After Prolonged Agonal Time in Non–Heart-Beating Donors

Kidney utilization in the Netherlands - do we optimally use our donor organs?

BACKGROUND

To ensure optimal utilization of deceased donor kidneys, it is important to understand the precise reasons why kidneys are discarded. In this study we aimed to obtain a comprehensive overview of kidney utilization and discard during the entire donation process in the Netherlands.

METHODS

In this retrospective cohort study we analysed kidney utilization of 3856 kidneys in the Netherlands between 1 January 2015 and 31 December 2020. For every kidney that was not transplanted, we determined the moment of and reason for discard through a unique case-by-case assessment.

RESULTS

Kidney discard according to the traditional definition (procured but not transplanted) was 7.8%. However, when kidneys that seemed medically suitable at the beginning of the donation process were also included, many more potential donor kidneys were lost and the total non-utilization was 24.4%. Subjectively presumed impaired organ quality was responsible for 34.2% of all discarded kidneys. Two-thirds of kidneys discarded due to acute kidney injury (AKI) had only AKI stage 1 or 2.

CONCLUSION

The classical definition of organ discard underestimates the non-utilization of deceased donor kidneys. Strategies to improve kidney utilization could be a revision of the maximum allowed agonal time in donation after circulatory death, careful consideration in reporting and accepting kidneys from donors with AKI and a prospectively filled registry of detailed organ discard reasons, including the 'silent' non-utilization before procurement.

Clinical use of donation after circulatory death pancreas for islet transplantation

Due to a shortage of donation after brain death (DBD) organs, donation after circulatory death (DCD) is increasingly performed. In the field of islet transplantation, there is uncertainty regarding the suitability of DCD pancreas in terms of islet yield and function after islet isolation. The aim of this study was to investigate the potential use of DCD pancreas for islet transplantation. Islet isolation procedures from 126 category 3 DCD and 258 DBD pancreas were performed in a 9-year period. Islet yield after isolation was significantly lower for DCD compared to DBD pancreas (395 515 islet equivalents [IEQ] and 480 017 IEQ, respectively; p = .003). The decrease in IEQ during 2 days of culture was not different between the two groups. Warm ischemia time was not related to DCD islet yield. In vitro insulin secretion after a glucose challenge was similar between DCD and DBD islets. After islet transplantation, DCD islet graft recipients had similar graft function (AUC C-peptide) during mixed meal tolerance tests and Igls score compared to DBD graft recipients. In conclusion, DCD islets can be considered for clinical islet transplantation.

Hypoperfusion warm ischaemia time in renal transplants from donors after circulatory death

Background

The donor hypoperfusion phase before asystole in renal transplants from donors after circulatory death (DCD) has been considered responsible for worse outcomes than those from donors after brain death (DBD).

Methods

We included 10 309 adult renal transplants (7128 DBD and 3181 DCD; 1 January 2010–31 December 2016) from the UK Transplant Registry. We divided DCD renal transplants into groups according to hypoperfusion warm ischaemia time (HWIT). We compared delayed graft function (DGF) rates, primary non-function (PNF) rates and graft survival among them using DBD renal transplants as a reference.

Results

The DGF rate was 21.7% for DBD cases, but ∼40% for DCD cases with HWIT ≤30 min (0–10 min: 42.1%, 11–20 min: 43%, 21–30 min: 38.4%) and 60% for DCD cases with HWIT >30 min (P < 0.001). All DCD groups showed higher DGF risk than DBD renal transplants in multivariable analysis {0–10 min: odds ratio [OR] 2.686 [95% confidence interval (CI) 2.352–3.068]; 11–20 min: OR 2.531 [95% CI 2.003–3.198]; 21–30 min: OR 1.764 [95% CI 1.017–3.059]; >30 min: OR 5.814 [95% CI 2.798–12.081]}. The highest risk for DGF in DCD renal transplants with HWIT >30 min was confirmed by multivariable analysis [versus DBD: OR 5.814 (95% CI 2.798–12.081) versus DCD: 0–10 min: OR 2.165 (95% CI 1.038–4.505); 11–20 min: OR 2.299 (95% CI 1.075–4.902); 21–30 min: OR 3.3 (95% CI 1.33–8.197)]. No significant differences were detected regarding PNF rates (P = 0.713) or graft survival (P = 0.757), which was confirmed by multivariable analysis.

Conclusions

HWIT >30 min increases the risk for DGF greatly, but without affecting PNF or graft survival.

DCD donor hemodynamics as predictor of outcome after kidney transplantation

Insufficient hemodynamics during agonal phase-ie, the period between withdrawal of life-sustaining treatment and circulatory arrest-in Maastricht category III circulatory-death donors (DCD) potentially exacerbate ischemia/reperfusion injury. We included 409 Dutch adult recipients of DCD donor kidneys transplanted between 2006 and 2014. Peripheral oxygen saturation (SpO2-with pulse oximetry at the fingertip) and systolic blood pressure (SBP-with arterial catheter) were measured during agonal phase, and were dichotomized into minutes of SpO2 > 60% or SpO2 < 60%, and minutes of SBP > 80 mmHg or SBP < 80 mmHg. Outcome measures were and primary non-function (PNF), delayed graft function (DGF), and three-year graft survival. Primary non-function (PNF) rate was 6.6%, delayed graft function (DGF) rate was 67%, and graft survival at three years was 76%. Longer periods of agonal phase (median 16 min [IQR 11-23]) contributed significantly to an increased risk of DGF (P = .012), but not to PNF (P = .071) and graft failure (P = .528). Multiple logistic regression analysis showed that an increase from 7 to 20 minutes in period of SBP < 80 mmHg was associated with 2.19 times the odds (95% CI 1.08-4.46, P = .030) for DGF. In conclusion, duration of agonal phase is associated with early transplant outcome. SBP < 80 mmHg during agonal phase shows a better discrimination for transplant outcome than SpO2 < 60% does.

Donor Hemodynamics as a Predictor of Outcomes After Kidney Transplantation From Donors After Cardiac Death

Donation after cardiac death is an important source of transplantable organs, but evidence suggests donor warm ischemia contributes to inferior outcomes. Attempts to predict recipient outcome using donor hemodynamic measurements have not yielded statistically significant results. We evaluated novel measures of donor hemodynamics as predictors of delayed graft function and graft failure in a cohort of 1050 kidneys from 566 donors. Hemodynamics were described using regression line slopes, areas under the curve, and time beyond thresholds for systolic blood pressure, oxygen saturation, and shock index (heart rate divided by systolic blood pressure). A logistic generalized estimation equation model showed that area under the curve for systolic blood pressure was predictive of delayed graft function (above median: odds ratio 1.42, 95% confidence interval [CI] 1.06-1.90). Multivariable Cox regression demonstrated that slope of oxygen saturation during the first 10 minutes after extubation was associated with graft failure (below median: hazard ratio 1.30, 95% CI 1.03-1.64), with 5-year graft survival of 70.0% (95%CI 64.5%-74.8%) for donors above the median versus 61.4% (95%CI 55.5%-66.7%) for those below the median. Among older donors, increased shock index slope was associated with increased hazard of graft failure. Validation of these findings is necessary to determine the utility of characterizing donor warm ischemia to predict recipient outcome.

Recommendations for donation after circulatory death kidney transplantation in Europe

Donation after circulatory death (DCD) donors provides an invaluable source for kidneys for transplantation. Over the last decade, we have observed a substantial increase in the number of DCD kidneys, particularly within Europe. We provide an overview of risk factors associated with DCD kidney function and survival and formulate recommendations from the sixth international conference on organ donation in Paris, for best-practice guidelines. A systematic review of the literature was performed using Ovid Medline, Embase and Cochrane databases. Topics are discussed, including donor selection, organ procurement, organ preservation, recipient selection and transplant management.

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.

Predicting donor asystole following withdrawal of treatment in donation after cardiac death

Donation after cardiac death donation allows donor pool expansion. The period between withdrawal of treatment and donor a systole is extremely variable; its prolongation often results in unsuccessful organ procurement. We sought to assess a variety of donor variables to determine whether they predicted successful organ retrieval. We included all Donation after Cardiac Death (DCD) retrievals between 2002 and 2009, which were grouped as successful (n = 104) versus unsuccessful (n = 42). Factors that predicted unsuccessful organ procurement included older donor age, donor history of hypertension, higher at withdrawal, and absence of inotropic support. On multivariate analysis, mean arterial pressure retained its significance. Prediction of withdrawal-to-asystole time is complex, but our analysis suggested that donor blood pressure at withdrawal is an important predictor of whether retrieval would be successful.

Renal transplantation following donation after cardiac death: impact of duration from withdrawal to asystole

Donation after cardiac death (DCD) allows for expansion of the donor pool, however, the process for DCD donation can lead to a donor's physiological instability before asystole. This may have a detrimental effect on graft and patient outcomes. We analyzed all 201 DCD donations at our unit from 2002 to 2009 and compared short versus long durations to asystole around the median time (20 min). Delayed graft function was comparable between the groups (P = .13), primary nonfunction was increased in the long duration to asystole group (P < .0001), and acute rejection was increased in the short duration group (P < .001). Five year patient survival was comparable (P = .6). In conclusion, long duration asystole may have an immediate effect on graft survival, but it has no overall detrimental effect on longer-term outcomes. Further studies are required to investigate the acceptable time to wait from withdrawal to asystole.

Donor postextubation hypotension and age correlate with outcome after donation after cardiac death transplantation

BACKGROUND

Compared with standard donors, kidneys recovered from donors after cardiac death (DCD) exhibit higher rates of delayed graft function (DGF), and DCD livers demonstrate higher rates of biliary ischemia, graft loss, and worse patient survival. Current practice limits the use of these organs based on time from donor extubation to asystole, but data to support this is incomplete. We hypothesized that donor postextubation parameters, including duration and severity of hemodynamic instability or hypoxia might be a better predictor of subsequent graft function.

METHODS

We performed a retrospective examination of the New England Organ Bank DCD database, concentrating on donor factors including vital signs after withdrawal of support.

RESULTS

Prolonged, severe hypotension in the postextubation period was a better predictor of subsequent organ function that time from extubation to asystole. For DCD kidneys, this manifested as a trend toward increased DGF. For DCD livers, this manifested as increased rates of poor outcomes. Maximizing the predictive value of this test in the liver cohort suggested that greater than 15 min between the time when the donor systolic blood pressure drops below 50 mm Hg and flush correlates with increased rates of diffuse biliary ischemia, graft loss, or death. Donor age also correlated with worse outcome.

CONCLUSIONS

Time between profound instability and cold perfusion is a better predictor of outcome than time from extubation to asystole. If validated, this information could be used to predict DGF after DCD renal transplant and improve outcomes after DCD liver transplant.

Non heart-beating donors in England

When transplantation started all organs were retrieved from patients immediately after cardio-respiratory arrest, i.e. from non heart-beating donors. After the recognition that death resulted from irreversible damage to the brainstem, organ retrieval rapidly switched to patients certified dead after brainstem testing. These heart-beating-donors have become the principal source of organs for transplantation for the last 30 years. The number of heart-beating-donors are declining and this is likely to continue, therefore cadaveric organs from non-heart-beating donor offers a large potential of resources for organ transplantation. The aim of this study is to examine clinical outcomes of non-heart-beating donors in the past 10 years in the UK as an way of decreasing pressure in the huge waiting list for organs transplantation.