In situ preservation of kidneys from donors after cardiac death: results and complications. Ann Surg. 2007;246:844-852. [PMID: 17968178 DOI: 10.1097/sla.0b013e318142cb1b]

A retrievable, dual-chamber stent protects against warm ischemia of donor organs in a model of donation after circulatory death

BACKGROUND

Ischemic injury during the agonal period of donation after circulatory death donors remains a significant barrier to increasing abdominal transplants. A major obstacle has been the inability to improve visceral perfusion, while at the same time respecting the ethics of the organ donor. A retrievable dual-chamber stentgraft could potentially isolate the organ perfusion from systemic hypotension and hypoxia, without increasing cardiac work or committing the donor.

METHODS

Retrievable dumbbell-shaped stents were laser welded from nitinol wire and covered with polytetrafluoroethylene. Yorkshire pigs were assigned to either agonal control or dumbbell-shaped dual-chamber stentgraft. A central lumen maintained aortic flow, while an outer visceral chamber was perfused with oxygenated blood. A 1-hour agonal phase of hypoxia and hypotension was simulated. Stents were removed by simple sheath advancement. Cardiac monitoring, labs, and visceral flow were recorded followed by recovery of the animal to a goal of 48 hours.

RESULTS

Cardiac stress did not increase during stent deployment. Visceral pO2 and flow were dramatically improved in stented animal relative to control animals. Five of 7 control animals were killed after renal failure complications, whereas all stent animals survived. Histology confirmed increased ischemic changes among control kidneys compared to stented animals.

CONCLUSION

A dual-chamber stent improved outcomes after a simulated agonal phase. The stent did not increase cardiac work, thus respecting a key ethical consideration. The ability of a dual-chamber stent to prevent ischemia during organ recovery may become a powerful tool to address the critical donor organ shortage.

A systematic review and meta-analyses of regional perfusion in donation after circulatory death solid organ transplantation

In donation after circulatory death (DCD), (thoraco)abdominal regional perfusion (RP) restores circulation to a region of the body following death declaration. We systematically reviewed outcomes of solid organ transplantation after RP by searching PubMed, Embase, and Cochrane libraries. Eighty-eight articles reporting on outcomes of liver, kidney, pancreas, heart, and lung transplants or donor/organ utilization were identified. Meta-analyses were conducted when possible. Methodological quality was assessed using National Institutes of Health (NIH)-scoring tools. Case reports (13/88), case series (44/88), retrospective cohort studies (35/88), retrospective matched cohort studies (5/88), and case-control studies (2/88) were identified, with overall fair quality. As blood viscosity and rheology change below 20 °C, studies were grouped as hypothermic (HRP, ≤20 °C) or normothermic (NRP, >20 °C) regional perfusion. Data demonstrate that RP is a safe alternative to in situ cold preservation (ISP) in uncontrolled and controlled DCDs. The scarce HRP data are from before 2005. NRP appears to reduce post-transplant complications, especially biliary complications in controlled DCD livers, compared with ISP. Comparisons for kidney and pancreas with ISP are needed but there is no evidence that NRP is detrimental. Additional data on NRP in thoracic organs are needed. Whether RP increases donor or organ utilization needs further research.

Comparative Analysis of Risk Factors in Declined Kidneys from Donation after Brain Death and Circulatory Death

Background and objectives: Kidneys from donation after circulatory death (DCD) are more likely to be declined for transplantation compared with kidneys from donation after brain death (DBD). The aim of this study was to evaluate characteristics in the biopsies of human DCD and DBD kidneys that were declined for transplantation in order to rescue more DCD kidneys. Materials and Methods: Sixty kidney donors (DCD = 36, DBD = 24) were recruited into the study and assessed using donor demographics. Kidney biopsies taken post cold storage were also evaluated for histological damage, inflammation (myeloperoxidase, MPO), von Willebrand factor (vWF) expression, complement 4d (C4d) deposition and complement 3 (C3) activation using H&E and immunohistochemistry staining, and Western blotting. Results: More DBD donors (16/24) had a history of hypertension compared with DCDs (8/36, p = 0.001). The mean warm ischemic time in the DCD kidneys was 12.9 ± 3.9 min. The mean cold ischemic time was not significantly different between the two groups of kidney donors (DBD 33.3 ± 16.7 vs. DCD 28.6 ± 14.1 h, p > 0.05). The score of histological damage and MPO, as well as the reactivity of vWF, C4d and C3, varied between kidneys, but there was no significant difference between the two donor types (p > 0.05). However, vWF reactivity might be an early indicator for loss of tissue integrity, while C4d deposition and activated C3 might be better predictors for histological damage. Conclusions: Similar characteristics of DCD were shown in comparison with DBD kidneys. Importantly, the additional warm ischemic time in DCD appeared to have no further detectable adverse effects on tissue injury, inflammation and complement activation. vWF, C4d and C3 might be potential biomarkers facilitating the evaluation of donor kidneys.

Similar 5-Year Estimated Glomerular Filtration Rate Between Kidney Transplants From Uncontrolled and Controlled Donors After Circulatory Death-A Dutch Cohort Study

BACKGROUND

Organ shortage persists despite a high rate of donation after circulatory death (DCD) in the Netherlands. The median waiting time for a deceased donor kidney in 2013 was 3.5 years. Most DCD kidneys are from controlled DCD (cDCD; Maastricht category III). Experience with uncontrolled donors after cardiac death (uDCD), that is, donors with an unexpected and irreversible cardiac arrest (Maastricht categories I and II), is increasing; and its effect on transplant outcomes needs evaluation.

METHODS

We used the Dutch Organ Transplantation Registry to include recipients (≥18 years old) from all Dutch centers who received transplants from 2002 to 2012 with a first DCD kidney. We compared transplant outcome in uDCD (n = 97) and cDCD (n = 1441).

RESULTS

Primary nonfunction in uDCD was higher than in the cDCD (19.6% vs 9.6%, P < 0.001, respectively). Delayed graft function was also higher in uDCD than in cDCD, but not significantly (73.7% vs 63.3%, P = .074, respectively). If censored for primary nonfunction, estimated glomerular filtration rates after 1 year and 5 years were comparable between uDCD and cDCD (1 year: uDCD, 44.3 (23.4) mL/min/m and cDCD, 45.8 (24.1) mL/min/m; P = 0.621; 5 years: uDCD, 49.1 (25.6) mL/min/m and cDCD, 47.7 (21.7) mL/min/m; P = 0.686). The differences in primary nonfunction between kidneys from uDCD and cDCD were explained by differences in the first warm ischemic period, cold ischemic time, and donor age.

CONCLUSIONS

We conclude that uDCD kidneys have potential for excellent function and can constitute a valuable extension of the donor pool. However, further efforts are necessary to address the high rate of primary nonfunction.

Successful Kidney and Lung Transplantation From a Deceased Donor With Blunt Abdominal Trauma and Intestinal Perforation

The number of organ donors is limited by many contraindications for donation and poor quality of potential organ donors. Abdominal infection is a generally accepted contraindication for donation of abdominal organs. We present a 43-year-old man with lethal brain injury, blunt abdominal trauma, and intestinal perforation. After withdrawal of life-sustaining treatment and circulatory arrest, a minilaparotomy confirmed abdominal contamination with intestinal content. After closure of the abdomen, organs were preserved with in situ preservation with an aortic cannula inserted via the femoral artery. Thereafter, the kidneys were procured via bilateral lumbotomy to reduce the risk of direct bacterial contamination; lungs were retrieved following a standard practice. There was no bacterial or fungal growth in the machine preservation fluid of both kidneys. All organs were successfully transplanted, without postoperative infection, and functioned well after 6 months. We hereby show that direct contamination of organs can be avoided with the use of in situ preservation and retroperitoneal procurement. Intestinal perforation is not an absolute contraindication for donation, although the risk of bacterial or fungal transmission has to be evaluated per case.

Ethical Issues in the Use of Extracorporeal Membrane Oxygenation in Controlled Donation After Circulatory Determination of Death

The use of donor extracorporeal membrane oxygenation (ECMO) to improve graft outcomes by some controlled donation after circulatory determination of death (cDCDD) programs raises ethical issues. We reviewed cDCDD protocols using ECMO and the relevant ethics literature to analyze these issues. It is not obvious that ECMO in cDCDD improves graft outcomes. In our opinion, ECMO implemented before death can interfere with end-of-life care and damage bodily integrity. By restoring systemic circulation, ECMO risks invalidating the preceding declaration of death if brain and cardiac perfusion is not adequately excluded because of malfunction or misplacement of the supradiaphragmatic aortic occlusion balloon. The use of ECMO is not compatible with the acronym DCDD because circulation is restored after the determination of death. Because of these deficiencies, we concluded that other techniques are preferable, such as rapid recovery or in situ cold infusion. If ECMO is performed, it requires a specific informed consent and transparency.

Controlled Donation After Circulatory Determination of Death

Controlled donation after circulatory determination of death (cDCDD) concerns donation after withdrawal of life-sustaining therapy (W-LST). We examine the ethical issues raised by W-LST in the cDCDD context in the light of a review of cDCDD protocols and the ethical literature. Our analysis confirms that W-LST procedures vary considerably among cDCDD centers and that despite existing recommendations, the conflict of interest in the W-LST decision and process might be difficult to avoid, the process of W-LST might interfere with usual end-of-life care, and there is a risk of hastening death. In order to ensure that the practice of W-LST meets already well-established ethical recommendations, we suggest that W-LST should be managed in the ICU by an ICU physician who has been part of the W-LST decision. Recommending extubation for W-LST, when this is not necessarily the preferred procedure, is inconsistent with the recommendation to follow usual W-LST protocol. As the risk of conflicts of interest in the decision of W-LST and in the process of W-LST exists, this should be acknowledged and disclosed. Finally, when cDCDD programs interfere with W-LST and end-of-life care, this should be transparently disclosed to the family, and specific informed consent is necessary.

An analysis of heart donation after circulatory determination of death

BACKGROUND

Heart donation after circulatory determination of death (DCDD) has provoked ethical debate focused primarily on whether heart DCDD donors are dead when death is declared and when organs are procured.

OBJECTIVE AND DESIGN

We rigorously analyse whether four heart DCDD programmes (Cape Town, Denver, Australia, Cambridge) respect the dead donor rule (DDR), according to six criteria of death: irreversible cessation of all bodily cells function (or organs), irreversible cessation of heart function, irreversible cessation of circulation, permanent cessation of circulation, irreversible cessation of brain function and permanent cessation of brain function.

CONCLUSIONS

Only death criteria based on permanency are compatible with the DDR under two conditions: (1) a minimum stand-off period of 5 min to ensure that autoresuscitation is impossible and that all brain functions have been lost and (2) no medical intervention is undertaken that might resume bodily or brain circulation. By our analysis, only the Australia heart DCDD programme using a stand-off period of 5 min respects the DDR when the criteria of death are based on permanency.

The use of ex-vivo normothermic perfusion for the resuscitation and assessment of human kidneys discarded because of inadequate in situ perfusion

Background

Many kidneys are rejected for transplantation due to inadequate in situ perfusion during organ retrieval because of the risk of additional ischaemic injury and microvasculature thrombosis. This study describes the use of ex vivo normothermic perfusion (EVNP) for the resuscitation and assessment of human kidneys that were discarded after inadequate in situ perfusion.

Methods

Twenty-two human kidneys were retrieved but then deemed unsuitable for transplantation, primarily due to inadequate in situ perfusion. After a period of static cold storage, kidneys were perfused for 60 min with an oxygenated red cell based solution at 36 °C.

Results

Nineteen out of 22 kidneys (86 %) were from DCD donors. During EVNP, kidneys were assessed and scored based on their macroscopic appearance, measures of renal blood flow and urine production. Kidneys were scored from 1 indicating the least injury to 5, indicating the worst. Twelve kidneys had an EVNP score of 1–2, 7 scored 3–4 and 3 kidneys scored 5. The EVNP score 5 kidneys had a low level of tubular function compared to the score 1–4 kidneys. Their perfusion parameters did not improve during EVNP and they were considered non-transplantable. There was no association between the histological evaluation and EVNP parameters.

Conclusion

EVNP restores function ex vivo and enables an assessment of kidneys that have been declined for transplantation due to inadequate in situ perfusion.

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.

Development of a preclinical model of donation after circulatory determination of death for translational application

Background

Extracorporeal membranous oxygenation is proposed for abdominal organ procurement from donation after circulatory determination of death (DCD). In France, the national Agency of Biomedicine supervises the procurement of kidneys from DCD, specifying the durations of tolerated warm and cold ischemia. However, no study has determined the optimal conditions of this technique. The aim of this work was to develop a preclinical model of DCD using abdominal normothermic oxygenated recirculation (ANOR). In short, our objectives are to characterize the mechanisms involved during ANOR and its impact on abdominal organs.

Methods

We used Large White pigs weighing between 45 and 55 kg. After 30 minutes of potassium-induced cardiac arrest, the descending thoracic aorta was clamped and ANOR set up between the inferior vena cava and the abdominal aorta for 4 hours. Hemodynamic, respiratory and biochemical parameters were collected. Blood gasometry and biochemistry analysis were performed during the ANOR procedure.

Results

Six ANOR procedures were performed. The surgical procedure is described and intraoperative parameters and biological data are presented. Pump flow rates were between 2.5 and 3 l/min. Hemodynamic, respiratory, and biochemical objectives were achieved under reproducible conditions. Interestingly, animals remained hemodynamically stable following the targeted protocol. Arterial pH was controlled, and natremia and renal function remained stable 4 hours after the procedure was started. Decreased hemoglobin and serum proteins levels, concomitant with increased lactate dehydrogenase activity, were observed as a consequence of the surgery. The serum potassium level was increased, owing to the extracorporeal circulation circuit.

Conclusions

Our ANOR model is the closest to clinical conditions reported in the literature and will allow the study of the systemic and abdominal organ impact of this technique. The translational relevance of the pig will permit the determination of new biomarkers and protocols to improve DCD donor management.

Changing pattern of donor selection criteria in deceased donor liver transplant: a review of literature

During the last couple of decades, with standardization and progress in surgical techniques, immunosuppression and post liver transplantation patient care, the outcome of liver transplantation has been optimized. However, the principal limitation of transplantation remains access to an allograft. The number of patients who could derive benefit from liver transplantation markedly exceeds the number of available deceased donors. The large gap between the growing list of patients waiting for liver transplantation and the scarcity of donor organs has fueled efforts to maximize existing donor pool and identify new avenues. This article reviews the changing pattern of donor for liver transplantation using grafts from extended criteria donors (elderly donors, steatotic donors, donors with malignancies, donors with viral hepatitis), donation after cardiac death, use of partial grafts (split liver grafts) and other suboptimal donors (hypernatremia, infections, hypotension and inotropic support).

The value of machine perfusion biomarker concentration in DCD kidney transplantations

BACKGROUND

Donation after cardiac death (DCD) increases the number of donor kidneys but is associated with more primary nonfunction (PNF) and delayed graft function (DGF). It has been suggested that biomarkers in the preservation solution of machine perfused kidneys may predict PNF, although evidence is lacking.

METHODS

We analyzed the diagnostic accuracy of the perfusate biomarkers glutathione S-transferase, lactate dehydrogenase (LDH), heart-type fatty acid binding protein, redox-active iron, interleukin (IL)-18, and neutrophil gelatinase-associated lipocalin to predict PNF and DGF in 335 DCD kidneys preserved by hypothermic machine perfusion at our center between 1 January 1997 and 1 January 2008. The diagnostic accuracy of these biomarkers to predict PNF was evaluated with the area under the receiver operating characteristics curves. Additionally, the risk of DGF and graft failure was assessed.

RESULTS

LDH and IL-18 concentrations were associated with PNF (odds ratio [95% confidence interval], 1.001 [1.000-1.002]; P=0.005 and 1.001 [1.000-1.002]; P=0.003, respectively) in a multivariate analysis; the diagnostic accuracy for PNF was "poor" for all biomarkers but increased to "fair" for redox-active iron and IL-18 in a multivariate analysis (area under the receiver operating characteristics curves, 0.701 and 0.700, respectively). LDH and IL-18 concentrations were associated with DGF; biomarker concentration was not associated with 1-year graft survival.

CONCLUSIONS

The diagnostic accuracy of the perfusate biomarkers glutathione S-transferase, LDH, heart-type fatty acid binding protein, redox-active iron, IL-18, and neutrophil gelatinase-associated lipocalin to predict viability of DCD kidneys varies from "poor" to "fair". Therefore, DCD kidneys should not be discarded because of high biomarker perfusate concentration.

Improvements in kidney transplantation from donors after cardiac death

To reduce the growing waiting list for kidney transplantation, we explored the limits of kidney transplantation from donors after cardiac death by liberally accepting marginal donor kidneys for transplantation. As the percentage of primary non-function (PNF) increased, we evaluated our transplantation program and implemented changes to reduce the high percentage of PNF in 2005, followed by a second evaluation over the period 2006-2009. Recipients of a kidney from a donor after cardiac death between 1998 and 2005 were analyzed, with PNF as outcome measure. During the period 2002-2005, the percentage of PNF increased and crossed the upper control limits of 12% which was considered as unacceptably high. After implementation of changes, this percentage was reduced to 5%, without changing the number of kidney transplantations from donors after cardiac death. Continuous monitoring of the quality of care is essential as the boundaries of organ donation and transplantation are sought. Meticulous donor, preservation, and recipient management make extension of the donor potential possible, with good results for the individual recipient. Liberal use of kidneys from donors after cardiac death may contribute to a reduction in the waiting list for kidney transplantation and dialysis associated mortality.

Characterization of the perfusate proteome of human donor kidneys

BACKGROUND

Preservation of deceased donor kidneys by hypothermic machine perfusion results in superior transplant outcomes as compared with static cold storage and provides the opportunity to measure biomarkers of cellular injury in perfusate samples. Identification of biomarkers predicting early graft dysfunction so far has met with limited success.

METHODS

Two-dimensional difference gel electrophoresis and mass spectrometry were used to explore the proteome of perfusate samples from machine-perfused human donor kidneys (N = 18) and to discover novel biomarkers of ischaemic acute kidney injury.

RESULTS

Thirty-two protein spots were successfully identified, representing 19 unique proteins that were derived from renal tissue and from residual plasma in the renal microcirculation. Two unidentified protein spots were significantly up-regulated, whereas one protein spot--identified as haptoglobin--was significantly down-regulated in the perfusate of ischaemically injured kidneys from donors after cardiac death as compared with kidneys from brain-dead donors who had not suffered warm ischaemic injury. Furthermore, two protein spots were up-regulated in kidneys that never functioned after transplantation, whereas one spot was up-regulated--identified as α1-antitrypsin--in kidneys with delayed graft function.

CONCLUSIONS

We provide the first description of the renal perfusate proteome and present preliminary evidence of differentially expressed biomarkers in human donor kidneys with different levels of acute ischaemic injury. Their diagnostic value for the selection of marginal kidneys in clinical transplantation should be determined in future studies.

Delayed graft function after kidney transplantation: the clinical perspective

Delayed graft function continues to pose a significant challenge to clinicians in the context of kidney transplantation. With the present disparity between supply and demand for organs, transplantation is proceeding with more marginal kidneys and therefore the problem of delayed graft function is likely to increase in the future. Although our understanding of the mechanism and risk factors for delayed graft function has improved, translation of this understanding into targeted clinical therapy to attenuate or manage established delayed graft function has been elusive. Based on current trends, the use of kidneys from expanded criteria or cardiac death donors will continue to expand, which will increase the prevalence of delayed graft function in the immediate postoperative setting. The aim of this article is to discuss and critique the available clinical evidence for targeted intervention in the prevention and management of delayed graft function and review emerging and experimental therapies.

Kidney donation after cardiac death

There is continuing disparity between demand for and supply of kidneys for transplantation. This review describes the current state of kidney donation after cardiac death (DCD) and provides recommendations for a way forward. The conversion rate for potential DCD donors varies from 40%-80%. Compared to controlled DCD, uncontrolled DCD is more labour intensive, has a lower conversion rate and a higher discard rate. The super-rapid laparotomy technique involving direct aortic cannulation is preferred over in situ perfusion in controlled DCD donation and is associated with lower kidney discard rates, shorter warm ischaemia times and higher graft survival rates. DCD kidneys showed a 5.73-fold increase in the incidence of delayed graft function (DGF) and a higher primary non function rate compared to donation after brain death kidneys, but the long term graft function is equivalent between the two. The cold ischaemia time is a controllable factor that significantly influences the outcome of allografts, for example, limiting it to < 12 h markedly reduces DGF. DCD kidneys from donors < 50 function like standard criteria kidneys and should be viewed as such. As the majority of DCD kidneys are from controlled donation, incorporation of uncontrolled donation will expand the donor pool. Efforts to maximise the supply of kidneys from DCD include: implementing organ recovery from emergency department setting; improving family consent rate; utilising technological developments to optimise organs either prior to recovery from donors or during storage; improving organ allocation to ensure best utility; and improving viability testing to reduce primary non function.

Kidney transplantation from a donor following cardiac death supported with extracorporeal membrane oxygenation

To expand the donor pool, organ donation after cardiac death (DCD) has emerged. However, kidneys from DCD donors have a period of long warm ischemia between cardiac arrest and the harvesting of the organs. Recently, we used extracorporeal membrane oxygenation (ECMO) to minimize ischemic injury during 'no touch' periods in a Maastricht category II DCD donor and performed two successful kidney transplantations. The kidneys were procured from a 49-yr-old male donor. The warm ischemia time was 31 min, and the time of maintained circulation using ECMO was 7 hr 55 min. The cold ischemia time was 9 hr 15 min. The kidneys were transplanted into two recipients and functioned immediately after reperfusion. The grafts showed excellent function at one and three months post-transplantation; serum creatinine (SCr) levels were 1.0 mg/dL and 0.8 mg/dL and the estimated glomerular filtration rates (eGFR) were 63 mL/min/1.73 m(2) and 78 mL/min/1.73 m(2) in the first recipient, and SCr levels were 1.1 mg/dL and 1.0 mg/dL and eGFR were 56 mL/min/1.73 m(2) and 64 mL/min/1.73 m(2) in the second recipient. In conclusion, it is suggested that kidney transplantation from a category II DCD donor assisted by ECMO is a reasonable modality for expanding donor pool.

Renovascular resistance of machine-perfused DCD kidneys is associated with primary nonfunction

Donation after cardiac death (DCD) has shown to be a valuable extension of the donor pool despite a higher percentage of primary nonfunction (PNF). Limiting the incidence of PNF is of vital importance. Renovascular resistance is believed to predict graft outcome; however the literature is inconsistent. Therefore, we studied whether renovascular resistance is associated with PNF and whether this parameter should be used to discard donor kidneys. All transplanted DCD kidneys preserved by machine perfusion at our center between 1993 and 2007 were analyzed (n = 440). The effects of renovascular resistance on PNF, delayed graft function (DGF), and graft and patient survival were examined using multivariable analyses; predictive quality by calculating the area under the curve (AUC). We showed that renovascular resistance at the start of machine perfusion was significantly and independently associated with PNF (OR 2.040, 95% CI 1.362-3.056; p = 0.001), and DGF (OR 2.345, 95% CI 1.110-4.955; p = 0.025). Predictive quality was moderate (0.609, 95% CI 0.538-0.681). Graft and patient survival were not associated with renovascular resistance. We conclude that renovascular resistance in DCD kidneys is an independent risk factor for PNF; however, the predictive value is relatively low.

Kidney transplantation from donors after cardiac death: uncontrolled versus controlled donation

Kidney donation after cardiac death has been popularized over the last decade. The majority of these kidneys are from controlled donors. The number of organs for transplantation can be further increased by uncontrolled donors after cardiac death. The outcome of uncontrolled compared to controlled donor kidney transplantation is relatively unknown. We compared the long-term outcome of kidney transplantation from uncontrolled (n = 128) and controlled (n = 208) donor kidneys procured in the Maastricht region from January 1, 1981 until January 1, 2008, and transplanted in the Eurotransplant region. The incidence of primary nonfunction and delayed graft function in both uncontrolled and controlled donor kidneys is relatively high (22% vs. 21%, and 61% vs. 56%, p = 0.43, respectively). Ten-year graft and recipient survival are similar in both groups (50% vs. 46%, p = 0.74 and 61% vs. 60%, p = 0.76, respectively). Estimated glomerular filtration rates 1 year after transplantation are 40 ± 16 versus 42 ± 19 mL/min/1.73 m(2) , p = 0.55, with a yearly decline thereafter of 0.67 ± 3 versus 0.70 ± 7 mL/min/1.73 m(2) /year, p = 0.97. The outcome of kidney transplantation from uncontrolled and controlled donors after cardiac death is equivalent. This justifies the expansion of the donor pool with uncontrolled donors to reduce the still growing waiting list for renal transplantation, and may stimulate the implementation of uncontrolled kidney donation programs.

Preservation techniques for donors after cardiac death kidneys

PURPOSE OF REVIEW

The purpose of the present review is to describe the techniques currently used to preserve kidneys from donors after cardiac death.

RECENT FINDINGS

Automated chest compression devices may be used to improve organ perfusion between cardiac death and preservation measures. Normothermic extracorporeal membrane oxygenation reduces warm ischemic injury and has the ability to improve organ viability in donors after cardiac death.

SUMMARY

Kidneys from donors after cardiac death expand the donor pool but are inevitably subjected to a period of warm ischemia. Reduction of warm ischemic injury to the organs improves transplant outcome. To reduce this injury in organs from donors after cardiac death, different preservation techniques are used. Automated chest compression devices improve organ perfusion between cardiac death and the start of organ preservation. In-situ preservation with double-balloon triple-lumen catheter is an easy technique to preserve organs in uncontrolled donors and is used in many centers to cool and flush the organs. In controlled donors, organs can also be flushed after laparotomy and direct cannulation of the aorta. Extracorporeal membrane oxygenation reduces warm ischemic injury and the use of normothermic perfusion seems promising. Optimal preservation is essential to improve the viability of kidneys from donors after cardiac death, to fully utilize this large donor pool.

Preservation of kidneys from controlled donors after cardiac death

BACKGROUND

Donation after cardiac death (DCD) expands the pool of donor kidneys, but is associated with warm ischaemic injury. Two methods are used to preserve kidneys from controlled DCD donors and reduce warm ischaemic injury: in situ preservation using a double-balloon triple-lumen catheter (DBTL) inserted via the femoral artery and direct cannulation of the aorta after rapid laparotomy. The aim of this study was to compare these two techniques.

METHODS

This was a retrospective cohort study of 165 controlled DCD procedures in two regions in the Netherlands between 2000 and 2006.

RESULTS

There were 102 donors in the DBTL group and 63 in the aortic group. In the aortic group the kidney discard rate was lower (4·8 versus 28·2 per cent; P < 0·001), and the warm (22 versus 27 min; P < 0·001) and the cold (19 versus 24 h; P < 0·001) ischaemia times were shorter than in the DBTL group. Risk factors for discard included preservation with the DBTL catheter (odds ratio (OR) 5·19, 95 per cent confidence interval 1·88 to 14·36; P = 0·001) and increasing donor age (1·05, 1·02 to 1·07; P < 0·001). Warm ischaemia time had a significant effect on graft failure (hazard ratio 1·04, 1·01 to 1·07; P = 0·009), and consequently graft survival was higher in the aortic cannulation group (86·2 per cent versus 76·8 per cent in the DBTL group at 1 year; P = 0·027).

CONCLUSION

In this retrospective study, direct aortic cannulation appeared to be a better method to preserve controlled DCD kidneys.

Kidney transplantation from donors after cardiac death: a 25-year experience

BACKGROUND

The shortage of organ donors presents a major obstacle for adequate treatment of patients with end-stage renal disease. Donation after cardiac death (DCD) has been shown to increase the number of kidneys available for transplantation. The present article reports on the first 25 years of our experience with DCD kidney transplantation.

METHODS

This observational cohort study included all DCD kidney transplantations recovered in our procurement area from January 1, 1981 until December 31, 2005 (n=297). Patients were followed up until the earliest of death or December 31, 2006. Clinical outcomes were compared with matched kidney transplantations from brain dead donors (DBD, n=594), using multivariable regression models to adjust for potential confounders.

RESULTS

DCD activity resulted in a 44% increase in the number of deceased donor kidneys from our organ procurement area. After adjustment for potential confounders, the odds of primary nonfunction and delayed graft function were 7.5 (95% CI, 4.0-14.1; P<0.001) and 10.3 (95% CI, 6.7-15.9; P<0.001) times greater, respectively, for DCD kidneys compared with DBD kidneys. The high incidence of primary nonfunction of DCD kidneys resulted in an increased rate of graft loss (HR, 1.82; 95% CI, 1.37-2.42; P<0.001). However, DCD kidneys that did not experience primary nonfunction functioned as long as DBD kidneys (HR, 1.05; 95% CI, 0.73-1.51; P=0.79). Patient survival of DCD and DBD kidney recipients was equivalent (HR, 1.16; 95% CI, 0.87-1.54; P=0.32).

CONCLUSIONS

The benefits of DCD kidney transplantation outweigh the increased risk of early graft loss. Expansion of the supply of DCD kidneys is likely to improve the treatment of wait-listed dialysis patients.

Tubular epithelial injury and inflammation after ischemia and reperfusion in human kidney transplantation

OBJECTIVE

To provide an integrated insight into the kinetics of tubular injury, inflammation, and oxidative stress after human kidney transplantation.

BACKGROUND

Tissue injury due to ischemia and reperfusion is an inevitable consequence of kidney transplantation. Tubular epithelial injury, inflammation, and oxidative stress play major roles in the pathophysiology of acute kidney injury in small animals, but it remains to be established whether this paradigm holds true for human kidney transplantation.

METHODS

Markers of tubular injury, inflammation, and oxidative stress were compared between recipients of kidneys from donors after cardiac death (DCD; N = 8) with prolonged ischemia and recipients of living donor kidneys with minimal ischemia (N = 8).

RESULTS

In the early postoperative period, creatinine clearance and tubular sodium reabsorption were profoundly reduced in DCD kidneys, coinciding with significantly increased urinary concentrations of tubular injury markers (neutrophil gelatinase-associated lipocalin, N-acetyl-β--glucosaminidase, and cystatin C) and an 18-fold increase in renal production of cytokeratin-18, indicating extensive necrotic cell death. Tubular injury in DCD kidneys was followed by greater systemic inflammatory activity and oxidative stress in the postoperative period (measured with 17-plex cytokine arrays and as plasma F2-isoprostanes, respectively). In contrast, no evidence of oxidative damage to either of the 2 kidney types was found in the early reperfusion period.

CONCLUSIONS

These findings establish the relevance of observations in animal models for human kidney transplantation and form the basis for development of novel therapies to improve early graft function and expand the use of donor kidneys with prolonged ischemia.

Acute ischemic injury to the renal microvasculature in human kidney transplantation

Increased understanding of the pathophysiology of ischemic acute kidney injury in renal transplantation may lead to novel therapies that improve early graft function. Therefore, we studied the renal microcirculation in ischemically injured kidneys from donors after cardiac death (DCD) and in living donor kidneys with minimal ischemia. During transplant surgery, peritubular capillaries were visualized by sidestream darkfield imaging. Despite a profound reduction in creatinine clearance, total renovascular resistance of DCD kidneys was similar to that of living donor kidneys. In contrast, renal microvascular perfusion in the early reperfusion period was 42% lower in DCD kidneys compared with living donor kidneys, which was accounted for by smaller blood vessel diameters in DCD kidneys. Furthermore, DCD kidneys were characterized by smaller red blood cell exclusion zones in peritubular capillaries and by greater production of syndecan-1 and heparan sulfate (main constituents of the endothelial glycocalyx) compared with living donor kidneys, providing strong evidence for glycocalyx degradation in these kidneys. We conclude that renal ischemia and reperfusion is associated with reduced capillary blood flow and loss of glycocalyx integrity. These findings form the basis for development of novel interventions to prevent ischemic acute kidney injury.

Histological assessment of pre-transplant kidney biopsies is reproducible and representative

AIMS

Histological examination of pre-transplant renal biopsy specimens can be used to select grafts from older donors after cardiac death (DCD) with a satisfactory transplant outcome. The aim was to determine whether such biopsy specimens can be reproducibly scored between pathologists and are representative of the whole kidney.

METHODS AND RESULTS

In renal biopsy specimens from DCD aged >or=60 years (n = 44), globally sclerosed glomeruli, vascular narrowing, tubular atrophy and interstitial fibrosis were scored by three independent pathologists according to the Pirani scoring system. Interobserver agreement on the sum of scores improved considerably with the introduction of a combined tubulo-interstitial scoring system (intraclass correlation coefficient increased from 0.38 to 0.64). In small needle biopsy specimens (n = 144) obtained at autopsy, estimates of the proportion of globally sclerosed glomeruli were more precise with increasing sample size. Reasonably precise estimates may be obtained from specimens with at least seven glomeruli.

CONCLUSIONS

It is feasible to implement pre-transplant renal biopsy specimen analysis as a selection criterion in clinical practice in order to accept kidneys from marginal donors for transplantation.

Kidney transplantation and donation in children

It has been shown that kidney transplantation results in superior life expectancy and quality of life compared with dialysis treatment for patients with end-stage renal disease. However, kidney transplantation in children differs in many aspects from adult kidney transplantation. This review focuses on specific issues of surgical care associated with kidney transplantation in children, including timing of transplantation, technical considerations, patient and graft survival, growth retardation and post-transplant malignancy. At the same time, there is a large discrepancy between the number of available donor kidneys and the number of patients on the waiting list for kidney transplantation. There is a general reluctance to use paediatric donor kidneys, because of relatively frequent complications such as graft thrombosis and early graft failure. We review the specific aspects of kidney transplantation from paediatric donors such as the incidence of graft thrombosis, hyperfiltration injury and 'en bloc' transplantation of two kidneys from one donor with an excellent long-term outcome, which is comparable with adult donor kidney transplantation. We also discuss the potential use of paediatric non-heart-beating donor kidneys, from donors whose heart stopped beating with the preservation techniques used.

Histological assessment of preimplantation biopsies may improve selection of kidneys from old donors after cardiac death

Kidneys from old donors after cardiac death (DCD) may increase the donor pool but the prognosis of these kidneys is unsatisfactory. To improve these results, we retrospectively evaluated the diagnostic utility of published selection algorithms for old donor kidneys. We studied all DCD kidney transplantations between January 1, 1994 and July 1, 2005 at our institution (n = 199). Selection algorithms were evaluated in the subset of kidney transplantations from donors aged 60 years or older (n = 52). For histological assessment of kidney biopsies, glomerulosclerosis, tubular atrophy, interstitial fibrosis and vascular narrowing were blindly scored. Functional kidney weight was calculated as renal mass multiplied by the fraction of nonsclerosed glomeruli. Graft function and survival of kidneys from DCD aged 60 years or older were inferior to those from younger DCD. Histological scores were associated with kidney function and graft survival of old DCD kidney transplantations. Functional kidney weight was associated with kidney function but not graft survival, while donor glomerular filtration rate (GFR), donor age and machine perfusion characteristics were associated with neither of the clinical outcomes of interest. We conclude that histological assessment of preimplantation biopsies may improve the selection of kidneys from old DCD and may therefore contribute to expansion of the donor pool.