Non-heart-beating donors from the streets: an increasing donor pool source

Identifying organ donors attended by prehospital healthcare professionals - A scoping review

INTRODUCTION

Organ donation is a life-saving intervention that provides hope for patients with end-stage organ failure, improving their longevity and quality of life. However, the demand for organs far exceeds the supply, leading to a significant disparity between patients on transplant waiting lists and the availability of suitable organs. To address this issue, innovative strategies, such as uncontrolled donation after circulatory death (uDCD) programs, have been proposed to expand the donor pool to the prehospital setting.

AIM

This study aimed to systematically map the literature and comprehensively evaluate the involvement of prehospital healthcare professionals in identifying potential organ donors, as well as the barriers and systems impacting this process.

METHODS

A scoping literature review was conducted guided by the PRISMA Extension for Scoping Reviews. Four electronic databases and grey literature were searched for articles examining the participation of prehospital healthcare professionals in the organ or tissue donation process. Relevant data were extracted, organised into narrative and tabular formats, and presented.

RESULTS

A total of 33 articles were included for analysis, predominantly focusing on uDCD programs. The review identified a limited evidence-base regarding the role of prehospital healthcare professionals in organ donation. Four common themes emerged: discrepancies in criteria, decision-making processes, bridging strategies, and ethical considerations.

CONCLUSION

This scoping literature review highlights the significant role of prehospital healthcare professionals in identifying and recruiting organ donors from non-traditional settings. Established uDCD systems show promise in alleviating the burden on transplant waitlists. However, there is a lack of consensus on enrolment criteria, transportation, and ethical considerations for uDCD. Further research is needed to address these gaps, establish evidence-based guidelines, and ensure the efficient and ethical utilisation of potential organ donors from unconventional settings.

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.

Estimating the potential pool of uncontrolled DCD donors in the United States

Organs from uncontrolled DCD donors (uDCDs) have expanded donation in Europe since the 1980s, but are seldom used in the United States. Cited barriers include lack of knowledge about the potential donor pool, lack of robust outcomes data, lack of standard donor eligibility criteria and preservation methods, and logistical and ethical challenges. To determine whether it would be appropriate to invest in addressing these barriers and building this practice, we sought to enumerate the potential pool of uDCD donors. Using data from the Nationwide Emergency Department Sample, the largest all-payer emergency department (ED) database, between 2013 and 2016, we identified patients who had refractory cardiac arrest in the ED. We excluded patients with contraindications to both deceased donation (including infection, malignancy, cardiopulmonary disease) and uDCD (including hemorrhage, major polytrauma, burns, and poisoning). We identified 9828 (range: 9454-10 202) potential uDCDs/y; average age was 32 years, and all were free of major comorbidity. Of these, 91.1% had traumatic deaths, with major causes including nonhead blunt injuries (43.2%) and head injuries (40.1%). In the current era, uDCD donors represent a significant potential source of unused organs. Efforts to address barriers to uDCD in the United States should be encouraged.

Preservation Solutions for Kidney Transplantation: History, Advances and Mechanisms

Solid organ transplantation was one of the greatest medical advances during the past few decades. Organ preservation solutions have been applied to diminish ischemic/hypoxic injury during cold storage and improve graft survival. In this article, we provide a general review of the history and advances of preservation solutions for kidney transplantation. Key components of commonly used solutions are listed, and effective supplementations for current available preservation solutions are discussed. At cellular and molecular levels, further insights were provided into the pathophysiological mechanisms of effective ingredients against ischemic/hypoxic renal injury during cold storage. We pay special attention to the cellular and molecular events during transplantation, including ATP depletion, acidosis, mitochondrial dysfunction, oxidative stress, inflammation, and other intracellular mechanisms.

Kidney transplant from uncontrolled donation after circulatory death donors maintained by nECMO has long-term outcomes comparable to standard criteria donation after brain death

Uncontrolled donation after circulatory death (uDCD) increases organ availability for kidney transplant (KT) with short-term outcomes similar to those obtained from donation after brain death (DBD) donors. However, heterogeneous results in the long term have been reported. We compared 10-year outcomes between 237 KT recipients from uDCD donors maintained by normothermic extracorporeal membrane oxygenation (nECMO) and 237 patients undergoing KT from standard criteria DBD donors during the same period at our institution. We further analyzed risk factors for death-censored graft survival in the uDCD group. Delayed graft function (DGF) was more common in the uDCD group (73.4% vs 46.4%; P < .01), although glomerular filtration rates at the end of follow-up were similar in the 2 groups. uDCD and DBD groups had similar rates for 10-year death-censored graft (82.1% vs 80.4%; P = .623) and recipient survival (86.2% vs 87.6%; P = .454). Donor age >50 years was associated with graft loss in the uDCD group (hazard ratio: 1.91; P = .058), whereas the occurrence of DGF showed no significant effect. uDCD KT under nECMO support resulted in similar graft function and long-term outcomes compared with KT from standard criteria DBD donors. Increased donor age could negatively affect graft survival after uDCD donation.

Caring for Patients or Organs: New Therapies Raise New Dilemmas in the Emergency Department

Two potentially lifesaving protocols, emergency preservation and resuscitation (EPR) and uncontrolled donation after circulatory determination of death (uDCDD), currently implemented in some U.S. emergency departments (EDs), have similar eligibility criteria and initial technical procedures, but critically different goals. Both follow unsuccessful cardiopulmonary resuscitation and induce hypothermia to "buy time": one in trauma patients suffering cardiac arrest, to enable surgical repair, and the other in patients who unexpectedly die in the ED, to enable organ donation. This article argues that to fulfill patient-focused fiduciary obligations and maintain community trust, institutions implementing both protocols should adopt and publicize policies to guide ED physicians to utilize either protocol for particular patients, in order to address the appearance of conflict of interest arising from the protocols' similarities. It concludes by analyzing ethical implications of incentives that may influence institutions to develop the expertise required for uDCDD but not EPR.

Transplant Coordination as the “Keystone” in Non—Heart-Beating Donations

The shortage of donated organs has become a problem in the transplantation world. Transplant teams are continuously looking for new ways to increase and improve the donor pool. Non—Heart-beating donors could be a source for increasing the number of donors, even though in some countries legal, ethical, or logistical problems obstruct the development of that source. The good results obtained by some groups working with Non—Heart-beating donors should stimulate others to implement this type of policy in their hospitals. We describe the origin and development of our policy on Non—Heart-beating donation, which has become the main source for organ donation in our hospital. We have found that the 5-year survival rate for kidneys from these donors is similar to the survival rate for kidneys obtained from brain-dead donors, and this encourages us to continue to use kidneys from Non—Heart-beating donors.

Experience With a New Process—Condition T—for Uncontrolled Donation After Circulatory Determination of Death in a University Emergency Department

Background:

In the United States, organ donation after circulatory death (DCD) determination is increasing among those who are removed from life-sustaining therapy but is rare when death is unexpected. We created a program for uncontrolled DCD (uDCD).

Methods:

A comprehensive program was created to train personnel to identify and respond quickly to potential donors after unexpected death. The process termed Condition T was implemented in the emergency department (ED) of 2 academic medical centers. All ED deaths were screened for uDCD potential. Eligible donors included patients with preexisting donor designation who received cardiopulmonary resuscitation, failed to respond, and were pronounced dead.

Results:

Over 350 nurses, physicians, perfusionists, organ procurement personnel, and administrators were trained. From February 2009 to June 2010, a total of 18 patients were potential Condition T candidates. Six Condition T responses were triggered. Three donors underwent cannulation, and 4 organs were recovered (3 kidney and 1 liver) from 2 donors. Time from Condition T trigger to perfusion with organ preservation solution ranged from 14 to 22.3 minutes. Perfusion duration was 197 and 221 minutes. No recovered organs were transplanted because biopsies showed prolonged warm ischemia.

Conclusions:

It is feasible to create a process to rapidly intervene in the ED for uDCD. However, no organ transplants resulted. The utility and sustainability of an uDCD program in this particular setting are questionable.

Donation after cardiac death and the emergency department: ethical issues

Organ donation after cardiac death (DCD) is increasingly considered as an option to address the shortage of organs available for transplantation, both in the United States and worldwide. The procedures for DCD differ from procedures for donation after brain death and are likely less familiar to emergency physicians (EPs), even as this process is increasingly involving emergency departments (EDs). This article explores the ED operational and ethical issues surrounding this procedure.

Uncontrolled organ donation after circulatory death: potential donors in the emergency department

BACKGROUND

The continuing shortfall of organs for transplantation has led to interest in Maastricht Category II (uncontrolled) Donation after Circulatory Death (DCD) organ donation. As preparation for a proposed pilot, this study aimed to explore the potential of uncontrolled DCD organ donation from patients presenting in cardiac arrest to the emergency department (ED) who are unsuccessfully resuscitated.

METHODS

We identified all patients who died in our ED following unsuccessful resuscitation after cardiac arrest who were aged between 16 years and 60 years, whose collapse was witnessed, in whom the paramedics arrived within 15 min, whose death in the ED was less than 2 h after their collapse, who were on the organ donation register and who arrived in the ED during the working week (Monday to Friday between 9:00 and 17:00).

RESULTS

During a 14-month period from 1 August 2008 to 30 September 2009, 564 patients had a cardiac arrest in the Lothian region. Four patients may have been eligible to participate in an uncontrolled DCD organ donation programme.

CONCLUSIONS

Identifying potential organ donors in the ED who are unsuccessfully resuscitated from cardiac arrest may contribute to reducing the shortfall of organs for transplantation, although numbers are likely to be small. If such a programme was to be introduced during weekday working hours, there may be around four donors a year. However, even one additional donor per year from hospitals across the UK with an ED and a transplantation service would add considerably to the overall organ donation rate.

Enhancing the tissue donor pool through donation after death in the field

INTRODUCTION

Tissue transplantation is an important adjunct to modern medical care and is used daily to save or improve patient lives. Tissue allografts include bone, tendon, corneas, heart valves and others. Increasing utilization may lead to tissue shortages, and tissue procurement organizations continue to explore ways to expand the cadaveric donor pool. Currently more than half of all deaths occur outside the acute care setting.

HYPOTHESIS

Many who suffer prehospital deaths might be eligible for non-organ tissue donation.

METHODS

A retrospective review of electronic prehospital medical records was conducted from May 1, 2008 through December 31, 2009. All prehospital deaths were included irrespective of cause. Once identified, additional medical history was obtained from prehospital, inpatient, and emergency department records. Age, medical history, and time of death were compared to exclusion criteria for four tissue procurement organizations (MTF, LifeNet, LifeCell, EyeBank). After analysis, percentages of eligible donors were calculated.

RESULTS

Over 50,000 prehospital records were reviewed; 432 subjects died in the field and were eligible for analysis. Ages ranged from four to 103 years of age; the average was 68.3 (SD = 20.1) years. After exclusion for age, medical conditions, and time of death, 185 unique patients (42.8%) were eligible for donation to at least one of the four tissue procurement organizations (range 11.6%-34.3%).

CONCLUSIONS

After prehospital death, many individuals may be eligible for tissue donation. These findings suggest that future prospective studies exploring tissue donation after prehospital death are indicated. These studies should aim to clarify eligibility criteria, create protocols and infrastructure, and explore the ethical implications of expanding tissue donation to include this population.

Out-hospital donors after cardiac death in Madrid, Spain: a 5-year review

OBJECTIVE

The Medical Emergencies Service of Madrid (Spain) (Servicio de Urgencias Medicas de Madrid), SUMMA112, forms part of an organ donor program involving patients who have suffered out-hospital cardiac arrest and fail to respond to advanced cardiopulmonary resuscitation maneuvers. Subjects meeting the inclusion criteria are moved to a transplant unit under sustained resuscitation maneuvering in order to harvest the organs. This paper presents compliance with the timelines of the program, the proportion of donors, the characteristics of donors and non-donors, and the number of organs obtained.

MATERIAL

A retrospective descriptive study was made based on the review of case histories. The SPSS(©) version 16.0 statistical package was used for data analysis.

RESULTS

A total of 214 cases were recorded, of which 84% were males. The mean age was 40 years. The mean time to arrival on scene was 13 min and 34 s. The mean time to arrival in hospital was 88 min and 10 s. A total of 522 organs and tissues were harvested (250 kidneys, 33 livers, 123 corneas, 97 bone tissues and 19 lungs), corresponding to 3.2 organs/tissues per patient on average. A total of 21.7% of the patients were not valid. There were no differences between the valid and non-valid patients in terms of age and gender. The causes of non-donation included extracorporeal circuit failure (6.3%), family refusal (15.6%), patient refusal expressed in life (4.7%), legal denial (1.6%), biological causes (51.6%), and others (20.3%). Cardiac compressors were used in 85 cases, yielding 92 kidneys, 41 corneas, 30 bone tissues, 19 livers and 9 lungs, corresponding to 2.1 organs/tissues per patient on average.

CONCLUSION

This program affords a very important number of organs for transplantation. Further studies are needed to assess the efficacy of mechanical cardiac compressor use in generating more organs.

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.

Non heart beating organ donor: new experimental model in pigs

PURPOSE

To describe technical aspects of a new experimental model that simulates a non heart beating organ donor.

METHODS

Landrace pigs were operated on and cardiac arrest was obtained by means of myocardial infarction and interruption of ventilator support.

RESULTS

Mean cardiac frequency, systolic and diastolic blood pressure levels, central venous pressure, oxygen saturation and concentration of expired CO(2) dropout occurred at seven minutes after cardiac arrest.

CONCLUSION

The procedure was easily reproduced and a homogeneous circulatory failure could de obtained by the end of seven minutes. The model is suitable for further studies regarding abdominal organ transplantation.

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.

The influence of storage temperature during machine perfusion on preservation quality of marginal donor livers

BACKGROUND

Although non-heart-beating donors have the potential to increase the number of available organs, the livers are used very seldom because of the risk of primary non-function. There is evidence that machine perfusion is able to improve the preservation of marginal organs, and therefore we evaluated in our study the influence of the perfusate temperature during oxygenated machine perfusion on the graft quality.

METHODS

Livers from male Wistar rats were harvested after 60-min warm ischemia induced by cardiac arrest. The portal vein was cannulated and the liver flushed with Lifor (Lifeblood Medical, Inc.) organ preservation solution for oxygenated machine perfusion (MP) at 4, 12 or 21 degrees C. Other livers were flushed with HTK and stored at 4 degrees C by conventional cold storage (4 degrees C-CS). Furthermore two groups with either warm ischemic damage only or without any ischemic damage serve as control groups. After 6h of either machine perfusion or cold storage all livers were normothermic reperfused with Krebs-Henseleit buffer, and functional as well as structural data were analyzed.

RESULTS

Contrary to livers stored by static cold storage, machine perfused livers showed independently of the perfusate temperature a significantly decreased enzyme release of hepatic transaminases (ALT) during isolated reperfusion. Increasing the machine perfusion temperature to 21 degrees C resulted in a marked reduction of portal venous resistance and an increased bile production.

CONCLUSIONS

Oxygenated machine perfusion improves viability of livers after prolonged warm ischemic damage. Elevated perfusion temperature of 21 degrees C reconstitutes the hepatic functional capacity better than perfusion at 4 or 12 degrees C.

Liver transplantation using uncontrolled non-heart-beating donors under normothermic extracorporeal membrane oxygenation

Because of the organ shortage, non-heart-beating donors have been proposed as a possible source of grafts for orthotopic liver transplantation (OLT). Despite the widespread use of controlled non-heart-beating donors, there are only a few published studies reporting the outcomes with uncontrolled non-heart-beating donors (UNHBDs). A prospective case-control study on adult patients undergoing OLT was designed. We used normothermic extracorporeal membrane oxygenation (NECMO) in all UNHBDs. Matching 2:1 ratio comparison was performed between a study group (UNHBDs) and a brain death donor (BDD) control group. Between January 2006 and March 2008, a total of 60 patients were included: 20 in the UNHBD group and 40 in the control group. The incidence of ischemic cholangiopathy was 5% (n = 1) for the UNHBD group and 0% for the BDD group (P = 0.15). The rate of primary nonfunction was 10% (n = 2) in UNHBD recipients and 2.5% (n = 1) in BDD recipients (P = 0.21), with graft loss in all of them. Three patients were retransplanted in the UNHBD group (15%), 2 of them because of primary nonfunction and 1 because of ischemic cholangiopathy; no patient was retransplanted in the control group (P = 0.012). After a mean follow-up of 330.4 +/- 224.9 days, 1-year cumulative patient survival was 85.5% for the UNHBD group and 87.5% for the BDD group (P = 0.768). One-year cumulative graft survival was 80% in the UNHBD group and 87.5% in the BDD group (P = 0.774). In conclusion, UNHBDs under NECMO are a potential source of organs for OLT with encouraging outcomes potentially comparable to those obtained with BDDs.

In defense of the reverence of all life: Heideggerean dissolution of the ethical challenges of organ donation after circulatory determination of death

During the past 50 years since the first successful organ transplant, waiting lists of potential organ recipients have expanded exponentially as supply and demand have been on a collision course. The recovery of organs from patients with circulatory determination of death is one of several effective alternative approaches recommended to reduce the supply-and-demand gap. However, renewed debate ensues regarding the ethical management of the overarching risks, pressures, challenges and conflicts of interest inherent in organ retrieval after circulatory determination of death. In this article, the author claims that through the engagement of a Heideggerean existential phenomenological and hermeneutic framework what are perceived as ethical problems dissolve, including collapse of commitment to the dead donor rule. The author argues for a revisioned socially constructed conceptual and philosophical responsibility of humankind to recognize the limits of bodily finitude, to responsibly use the capacity of the transplantable organs, and to grant enhanced or renewed existence to one with diminished or life-limited capacity; thereby making the locus of ethical concern the donor-recipient as unitary ''life.'' What ethically matters in the life-cycle (life-world) of donor-recipient is the viability of the organs transplanted; thereby granting reverence to all life.

Non-heart beating organ donation: overview and future perspectives

New indications for organ transplantation combined with a stagnating number of available donor grafts have severely lengthened the waiting list for almost all types of transplantations. This has led to a renewed interest in non-heart beating (NHB) donation, as a possible solution to bridge the gap between supply and demand. In this review, we present an overview of current NHB donation practice, outcome, existing problems and future perspectives. We focus on possible improvements in donor management, recipient care and new methods of organ preservation that may be better suited for these marginal organs. Successful institution of NHB protocols depends on adapting current transplantation practice at all levels, which is one of the greatest challenges for researchers and professionals in this interesting re-emerging field.

Non-heart-beating kidney transplantation: 6-year outcomes

Non-heart-beating donor kidneys (NHBD) are being used to increase the donor pool due to the scarcity of cadaveric heart beating donors (HBD). We evaluated the long-term outcomes of renal transplantation using NHBD kidneys, comparing the first 100 NHBD kidneys transplanted at our facility to the next consecutive cadaveric HBD kidneys for graft survival, recipient survival, and quality of graft function. Recipient survival (P = .22) and graft survival (P = .19) at 6 years did not differ between recipients of NHBD (83%, 80%) and HBD (89%, 87%) kidneys. Quality of graft function using the mean glomular filtration rates were significantly lower in the NHBD group up to 3 months following discharge (41 +/- 2 vs 47 +/- 2, P = .007) but were then comparable up to 6 years following transplantation (43 +/- 5 vs 46 +/- 4, P = .55).

Non-heartbeating donation of kidneys for transplantation

There is a persistent shortage of kidneys available for transplantation. In the early 1980s, therefore, we published the concept of non-heartbeating (NHB) donation; that is, procurement of kidneys from donors whose death has been accompanied by irreversible circulatory arrest. NHB donors are generally categorized using four definitions; category III (awaiting cardiac arrest) and category IV (cardiac arrest while braindead)--or 'controlled'--donors are the most suitable for initiating NHB donation programs. Delayed graft function is associated with use of kidneys from such donors, but has no effect on graft survival in the short or long term. Use of kidneys from category I (dead upon arrival at hospital) and category II (unsuccessfully resuscitated), or 'uncontrolled', donors is likewise associated with delayed graft function, but also with an increased risk of primary nonfunction. Viability testing of donated organs from these sources is a prerequisite for transplantation. Machine preservation parameters and enzyme release measurements help to distinguish viable from nonviable kidneys. The proportion of NHB donor kidneys in the total pool of postmortem kidneys differs considerably between countries. In The Netherlands, the proportion is nearly 50%. This figure is markedly higher than that in the US and Canada, where national programs have now been initiated to increase rates of NHB donation. In the future, warm preservation techniques might facilitate better viability testing, thereby increasing NHB donation from category I and II donors and further reducing the shortage of kidneys available for transplantation.

Graft function after kidney transplantation from non-heartbeating donors according to maastricht category

PURPOSE

Donor shortages have led to some groups using alternative sources such as non-heartbeating donors (NHBDs). Kidneys from NHBDs suffer from warm ischemia at cardiac arrest which is reflected by acute tubular necrosis of the allograft, resulting in a period of delayed graft function. NHBDs are categorized by the circumstances surrounding the agonal events of death which reflect differences in the likelihood of ischemic injury to the kidney. In this study we determined the impact of ischemic injury on the renal function of kidneys procured from different categories of NHBDs.

MATERIALS AND METHODS

From 1998 to 2003, 144 kidneys were procured from 72 NHBDs resulting in 93 transplants characterized into Maastricht categories II, III and IV NHBD renal transplants. Renal function after transplant was evaluated from the last dialysis until discharge from hospital, and then at 3 monthly intervals thereafter.

RESULTS

Primary warm ischemic time is more prolonged in the uncontrolled donor (category II) than controlled donor (category III greater than IV). Delayed graft function occurs more frequently (Maastricht category II 83.8%, III 67.4% and IV 0%, ANOVA p <0.05) and the return to normal function is more prolonged in uncontrolled donors. This is illustrated by the greater incidence of acute tubular necrosis (Maastricht category II 81.1%, III 65.2% and IV 50.0%, ANOVA p = nonsignificant) in the kidney allograft. There was no difference in year 1 allograft survival (Maastricht category II 83.9%, III 92.5% and IV 100%, ANOVA p = nonsignificant).

CONCLUSIONS

Early graft function is poorest in kidneys derived from Maastricht category II donors and best in category IV with III in-between. However, after 3 months the function of kidneys from all donors is the same.

Donation after cardiac death: the University of Wisconsin experience with liver transplantation

OBJECTIVE

To determine whether the outcomes of liver transplantation (LTx) from donation after cardiac death (DCD) donors are equivalent to those from donation after brain death (DBD) donors.

SUMMARY BACKGROUND DATA

Because of the significant donor organ shortage, more transplant centers are using livers recovered from DCD donors. However, long-term, single-center outcomes of liver transplantation from DCD donors are limited.

METHODS

From January 1, 1993, to July 31, 2002, 553 liver transplants were performed from DBD donors and 36 were performed from DCD donors. Differences in event rates between the groups were compared with Kaplan-Meier estimates and the log-rank test. Differences in proportion and differences of means between the groups were compared with Fisher exact test and the Wilcoxon rank sum test, respectively.

RESULTS

Mean warm ischemic time at recovery in the DCD group was 17.8 +/- 10.6 minutes. The overall rate of biliary strictures was greater in the DCD group at 1 year (33% versus 10%) and 3 years (37% versus 12%; P = 0.0001). The incidence of hepatic artery thrombosis, portal vein stenosis/thrombosis, ischemic-type biliary stricture (ITBS), and primary nonfunction were similar between groups. However, the incidence of both hepatic artery stenosis (16.6% versus 5.4%; P = 0.001) and hepatic abscess and biloma formation (16.7% versus 8.3%; P = 0.04) were greater in the DCD group. Trends toward worse patient and graft survival and increased incidence of ITBS were seen in DCD donors greater than 40 years compared with DCD donors less than 40 years. Overall patient survival at 1 year (DCD, 80%; versus DBD, 91%) and 3 years (DCD, 68%; versus DBD, 84%) was significantly less in the DCD group (P = 0.002). Similarly, graft survival at 1 year (DCD, 67%; versus DBD, 86%) and 3 years (DCD, 56%; versus DBD, 80%) were significantly less in the DCD group (P = 0.0001).

CONCLUSIONS

Despite similar rates of primary nonfunction, LTx after controlled DCD resulted in worse patient and graft survival compared with LTx after DBD and increased incidence of biliary complications and hepatic artery stenosis. However, overall results of LTx after controlled DCD are encouraging; and with careful donor and recipient selection, LTx after DCD may successfully increase the donor liver pool.

Do Recipients of Kidneys From Donors Treated With Streptokinase Develop Anti-streptokinase Antibodies?

Streptokinase is used for preflush for non-heart-beating donors (NHBDs) in our center. The aim of this study was to evaluate whether the use of thrombolytic streptokinase results in the production of anti-streptokinase antibodies in the recipients after renal transplantation. Recipient sera taken prior to and at 1 and 6 months posttransplant were tested for the presence of antibodies to streptokinase using an enzyme-linked immunosorbent assay assay. No differences were detected between a group of 18 recipients who had kidneys from thrombolytic-treated NHBDs and a further group of 18 who received NHBD kidneys without such treatment.

Improved rat liver preservation by hypothermic continuous machine perfusion using polysol, a new, enriched preservation solution

For experimental machine perfusion (MP) of the liver, the modified University of Wisconsin solution (UW-G) is most often used. In our search for an enriched MP preservation solution, Polysol was developed. Polysol is enriched with various amino acids, vitamins, and other nutrients for the liver metabolism. The aim of this study was to compare Polysol with UW-G for MP preservation of the liver. Rat livers were preserved during 24 hours with hypothermic MP using UW-G (n = 5) or Polysol (n = 5). Hepatocellular damage (aspartate aminotransferase [AST], alanine aminotransferase [ALT], lactate dehydrogenase [LDH], alpha-glutathione-S-transferase [alpha-GST]) and bile production were measured during 60 minutes of reperfusion (37 degrees C) with Krebs-Henseleit buffer. Control livers were reperfused after 24 hours of cold storage in UW (n = 5). MP using UW-G or Polysol showed less liver damage when compared with controls. Livers machine perfused with Polysol showed less enzyme release when compared to UW-G. Bile production was higher after MP using either UW-G or Polysol compared with controls. In conclusion, machine perfusion using Polysol results in better quality liver preservation than cold storage with UW and machine perfusion using UW-G.

Non-heart-beating donation: current state of the art

The use of non-heart-beating donors (NHBD) helps us to deal with the problem of the organ shortage. In addition to difficulties with legal and ethical acceptability, there are concerns regarding medical safety, which prevent the widespread use of these donors. To make optimum use of this potential organ supply, the ischemic injury that occurs after a period of warm ischemia needs to be reversed. To minimize the warm ischemia time, once the subject is declared dead, most centers commence in situ cold perfusion via a femoral access or a rapid aortic cannulation. This usually occurs within minutes of arriving at the emergency department, before the next of kin have been notified of the patient's death. The European experience of kidney transplantation from NHBD shows promising results. The long-term outcomes are similar to HBD kidneys notwithstanding a higher rate of delayed graft function, which seems not to affect the long-term survival of these kidneys. In summary, NHBD may have an important impact on the large discrepancy that exists between the organ supply and the demand. Current data suggest that the results may be further improved by better patient selection and retrieval team organization.

Liver transplantation from non-heart-beating donors: current status and future prospects

Liver transplantation is the treatment of choice for many patients with acute and chronic liver failure, but its application is limited by a shortage of donor organs. Donor organ shortage is the principal cause of increasing waiting lists, and a number of patients die while awaiting transplantation. Non-heart-beating donor (NHBD) livers are a potential means of expanding the donor pool. This is not a new concept. Prior to the recognition of brainstem death, organs were retrieved from deceased donors only after cardiac arrest. Given the preservation techniques available at that time, this restricted the use of extrarenal organs for transplantation. In conclusion, after establishment of brain death criteria, deceased donor organs were almost exclusively from heart-beating donors (HBDs). To increase organ availability, there is now a resurgence of interest in NHBD liver transplantation. This review explores the basis for this and considers some of the published results.

Preservation of porcine non-heart-beating donor livers by sequential cold storage and warm perfusion

BACKGROUND

Normothermic perfusion has been shown to resuscitate and maintain viability of non-heart-beating donor (NHBD) livers that have undergone significant warm ischemic injury. However, the logistics of clinical organ retrieval are complex, and a period of cold storage before warm preservation would simplify the process. We have investigated the effects of short duration of cold preservation before normothermic preservation on the function of porcine NHBD livers.

METHODS

Porcine livers were subjected to 60 minutes of warm ischemia and then assigned to the following groups: group W (n=5), normothermic preservation for 24 hours; and group C (n=4), cold preservation in University of Wisconsin solution for 4 hours followed by normothermic preservation for 20 hours (total preservation time 24 hours). Outcome parameters that were measured included bile production, serum transaminases and hyaluronic acid levels (cellular damage), and base deficit and glucose use (metabolic function).

RESULTS

Group W livers had superior bile production, metabolic activity (base deficit and greater glucose use), and less evidence of hepatocellular damage (alanine aminotransferase, aspartate aminotransferase), and sinusoidal endothelial cell dysfunction (hyaluronic acid). Group C livers showed greater necrosis and destruction of architecture on histology.

CONCLUSION

Normothermic perfusion failed to resuscitate porcine livers after 60 minutes of warm ischemia and 4 hours of cold preservation. Even a short period of cold ischemia is significantly deleterious to the function of ischemically damaged (NHBD) livers.

Liver transplantation from Maastricht category 2 non-heart-beating donors

BACKGROUND

The demand for liver transplantation has increasingly exceeded the supply of cadaver donor organs. Non-heart-beating donors (NHBDs) may be an alternative to increase the cadaver donor pool.

METHODS

The outcome of 20 liver transplants from Maastricht category 2 NHBDs is compared with 40 liver transplants from heart-beating donors (HBDs). After unsuccessful cardiopulmonary resuscitation (CPR), cardiopulmonary support (CPS) with simultaneous application of chest and abdominal compression (n=6), and cardiopulmonary bypass (CPB; n=14), which was hypothermic (n=7) or normothermic (n=7), were used to preserve the organs from NHBDs. Factors that may influence the outcome of livers from Maastricht category 2 NHBDs were also investigated.

RESULTS

With a minimum follow-up of 2 years, actuarial patient and graft survivals with livers from Maastricht category 2 NHBDs were 80% and 55%, respectively. Transplantation of organs from these donors was associated with a significantly higher incidence of primary nonfunction, biliary complications, and more severe initial liver dysfunction compared with livers from HBDs. Graft survival was 83% in livers from NHBDs preserved with CPS and 42% in those maintained with CPB. No graft failed if the duration of warm ischemia did not exceed 130 min with CPR or CPS, and if the period of CPB did not surpass 150 min when this method was used after CPR, regardless if it was hypothermic or normothermic.

CONCLUSION

Livers from Maastricht type 2 NHBDs may be used for transplantation if the period of warm ischemia during CPR or CPS does not exceed 130 min. Hypothermic or normothermic CPB after CPR preserves liver viability for an additional 150 min.

Brain stem death and organ donation—11 years on

BACKGROUND

We studied previously patterns of organ donation in a teaching hospital. Eleven years later we repeated the study to investigate how patterns had changed. We also wanted to see whether non-heart beating donation was being practised in our intensive care units.

METHODS

All deaths were prospectively audited to identify potential heart beating and non-heart beating organ donors. The actual organ donors and reasons for not donating were identified.

RESULTS

Overall, there was a significant reduction in the number of potential organ donors in the 11-yr period. This was accompanied by an increase in refusal rates by relatives from 10 to 29%, and a decrease in refusal rates by the coroner from 28 to 11%.

CONCLUSIONS

In this hospital the number of potential and actual organ donors has fallen in 11 yr. This is a combination of decreasing numbers of patients becoming brain dead and increased relative refusal rate. It has only been partially offset by a more liberal attitude of the coroner and non-heart beating donors.

Extended criteria for organ acceptance. Strategies for achieving organ safety and for increasing organ pool

The terms extended donor or expanded donor mean changes in donor acceptability criteria. In almost all cases, the negative connotations of these terms cannot be justified. Factors considered to affect donor or organ acceptability have changed with time, after showing that they did not negatively affect graft or patient survival per se or when the adequate measures had been adopted. There is no age limit to be an organ donor. Kidney and liver transplantation from donors older than 65 years can have excellent graft and patient actuarial survival and graft function. Using these donors can be from an epidemiological point of view the most important factor to esablish the final number of cadaveric liver and kidney transplantations. Organs with broad structural parenchyma lesion with preserved functional reserve and organs with reversible functional impairment can be safely transplanted. Bacterial and fungal donor infection with the adequate antibiotic treatment of donor and/or recipient prevents infection in the latter. The organs, including the liver, from donors with infection by the hepatitis B and C viruses can be safely transplanted to recipients with infection by the same viruses, respectively. Poisoned donors and non-heart-beating donors, grafts from transplant recipients, reuse of grafts, domino transplant and splitting of one liver for two recipients can be an important and safe source of organs for transplantation.

Use of older controlled non-heart-beating donors for liver transplantation

BACKGROUND

Use of liver grafts from non-heart-beating donors (NHBDs) warrants consideration so to expand the donor pool. Because the results of controlled NHBDs (CNHBDs) were acceptable, we have recently tried to expand the criteria to older CNHBDs. Here, we report our experience using liver grafts from older CNHBDs.

METHODS

We retrospectively studied our donor records from June 1994 through December 2001. CNHBDs were divided into two groups by age: older donors (O) were more than or equal to 55 years old, and younger donors (Y) were less than 55 years old. We compared donor and recipient demographics and peak laboratory values during the first postoperative week.

RESULTS

Twenty-five grafts from CNHBDs were transplanted in our center. Five livers were harvested from O (63+/-6 years) and 20 were from Y (32+/-15 years). No differences other than age in donor characteristics were noted between O and Y. Mean age of recipients was 50 years in both groups. Mean cold ischemic time (CIT) was 5.4 hours in O and 7.3 hours in Y (P<.05). Peak glutamic oxaloacetic transaminase (U/L), glutamic pyruvic transaminase (U/L), bilirubin (mg/dL), and prothrombin time (sec) during the first postoperative week were 611, 500, 3.9, and 16 in O and 846, 593, 5.9, and 17 in Y. There were no significant differences between the two groups. The graft survival at 1 year was 80% in O and 70% in Y.

CONCLUSIONS

In our preliminary experience, recipients of liver grafts from older CNHBDs had an outcome equivalent to that of younger CNHBDs. With the strict evaluation of the donors and brief CIT, liver grafts from older CNHBDs may be used to expand the donor pool.

Nonheart-beating kidney donation: current practice and future developments

BACKGROUND

Nonheart-beating kidney donation (NHBD) is gaining acceptance as a method of donor pool expansion. However, a number of practitioners have concerns over rates of delayed graft function, acute rejection, and long-term graft survival. The ethical issues associated with NHBD are complex and may be a further disincentive. Tailored strategies for preservation, viability prediction, and immunosuppression for kidneys from this source have the potential to maximize the number of available organs. This review article presents the current practice of NHBD kidney transplantation, examines the results and draws comparisons with cadaveric kidneys, and explores some areas of potential development.

METHODS

A review of the current literature on NHBD kidney donation was performed.

RESULTS

The renewed interest in NHBD kidneys is driven by a continuing shortfall in available organs. Those centers involved in NHBD report an increase in kidney transplants of the order of 16% to 40% and there is no evidence that the financial costs are higher with NHBDs. The majority of experience comes from Maastricht category 2 NHBDs, where an estimation of warm time is possible. This is generally limited to 40 minutes. There are variations in the technique for kidney preservation prior to retrieval, but most centers use an aortic balloon catheter. Much work has looked at the ideal technique for kidney preservation prior to implantation. Evidence suggests that machine perfusion produces the best initial function rates, decreased use of adjuvant immunotherapy and fewer haemodialysis sessions than static cold storage.

CONCLUSION

Despite being associated with poorer initial graft function, the long-term allograft survival of NHBD kidneys does not differ from the results of transplantation from cadaveric kidneys. Further, serum creatinine levels are generally equivalent. Constant reassessment of the ethical issues is required for donation to be increased while respecting public concerns. Use of viability assessment and tailoring of immune suppression for NHBD kidneys may allow a further increase in donation from this source.

Long-term renal function in kidneys from non-heart-beating donors: A single-center experience

BACKGROUND

Cadaveric kidneys from brain-stem-dead donors continue to be limited because the number of donors has reached a plateau. Wide recruitment of non-heart-beating donors (NHBD) could significantly increase the donor pool. NHBD renal transplants are underused because of the concern of poor quality graft function from such donors. In response to this perception, we reviewed 46 NHBD renal transplants performed in our center since 1998.

METHODS

All NHBD kidneys were machine-perfused using the Newcastle continuous-hypothermic pulsatile preservation system before transplantation. A control heart-beating-donor (HBD) group was taken as the next consecutive HBD renal transplant to the NHBD transplant. The outcome and quality of function of the groups of renal transplants were analyzed for short-term and long-term performance.

RESULTS

The renal transplant patients were matched for donor and recipient factors. Survival rates for allografts and patients were similar for 1 to 3 years. There was an increased incidence of delayed graft function in the NHBD renal transplants in the perioperative period. The creatinine clearance was 22.8+/-2.3 mL/minute for NHBD patients and 44.4+/-2.9 mL/minute for HBD patients at the time of discharge from hospital. This difference equalized after 3 months and the creatinine clearance for NHBD was 44.2+/-2.4 mL/minute and for HBD 49.2+/-3.4 mL/minute.

CONCLUSIONS

Our results for NHBD renal transplants confirm that such grafts suffer primary warm ischemic injury, shown by the increased incidence of acute tubular necrosis and consequent delayed graft function. This produced poor renal function at the time of hospital discharge. After 3 months, the renal function of NHBD cases improved to the level seen in HBD patients.

Transplant coordination as the "keystone" in non-heart-beating donations

The shortage of donated organs has become a problem in the transplantation world. Transplant teams are continuously looking for new ways to increase and improve the donor pool. Non--heart-beating donors could be a source for increasing the number of donors, even though in some countries legal, ethical, or logistical problems obstruct the development of that source. The good results obtained by some groups working with non--heart-beating donors should stimulate others to implement this type of policy in their hospitals. We describe the origin and development of our policy on non--heart-beating donation, which has become the main source for organ donation in our hospital. We have found that the 5-year survival rate for kidneys from these donors is similar to the survival rate for kidneys obtained from brain-dead donors, and this encourages us to continue to use kidneys from non--heart-beating donors.

Improving the quality of kidneys from non-heart-beating donors, using streptokinase: an animal model

BACKGROUND

Non-heart-beating donors (NHBD) offer a promising potential to increase the cadaveric organ donor pool, especially for kidneys. However, almost half of NHBD kidneys are discarded after viability assessment. This wastage is costly in both human and monetary terms. Intravascular thrombosis at the time of donor death is an event leading to failure in the viability assessment. We have developed an animal model to investigate the effects of the addition of streptokinase to the in situ flush medium before transplant in an attempt to redress the situation.

METHODS

Two groups of eight healthy young Landrace Yorkshire white pigs were entered into the study. Both groups were subjected to approximately 70 min warm ischemia. Both groups received an intravascular flush with 4 L of Marshall's solution with heparin (1000 IU/L); one group of pigs also had streptokinase (1.5 MIU/L) added. After donor nephrectomy, all kidneys were machine perfused for 4 hr. Data on perfusion characteristics were taken and samples of kidney effluent were assayed for tissue damage biomarkers, glutathione S-transferase (GST) and alanine aminopeptidase (Ala-AP). Wedge sections of porcine kidneys were taken at the end of perfusion, for histological analysis.

RESULTS

Data on machine perfusion parameters (temperature, mean pressure index, resistance) indicate better cooling, lower resistance, and lower mean pressure index in the streptokinase-treated group of pigs. GST and Ala-AP levels were increased in the nonstreptokinase group perfusates. Histopathological analysis of porcine kidneys indicated more ischemic injury and tissue damage in the nonstreptokinase group.

CONCLUSION

The use of streptokinase in this porcine NHBD model conferred benefits to donor kidneys when assessed by machine perfusion. Markers of biochemical injury indicated that less renal tissue damage occurred with the incorporation of streptokinase in the in situ flush medium.