Safety and Outcomes in 100 Consecutive Donation After Circulatory Death Liver Transplants Using a Protocol That Includes Thrombolytic Therapy

Advances and Challenges of Thrombolytic Therapy for Donation After Circulatory Death Organs

The demand for organ transplantation has exceeded the global supply of available organs. Donation after circulatory death (DCD) is considered an effective method to solve the disparity between the supply and demand of organs, by expanding the donor pool. However, DCD organs experience long-term damage caused by warm ischemia (WI) and microthrombosis caused by diffuse intravascular coagulation. Unfortunately, because of concerns about post-transplantation complications, most organs considered high-risk are discarded, resulting in wasted medical resources and economic losses. However, thrombolytic therapy before transplantation may dissolve microthrombosis in DCD organs, improve organ microcirculation, and increase organ use. Herein, we review the current status and potential value of thrombolytic therapy before DCD organ transplantation, summarize the progress of thrombolytic therapy for DCD organ transplantation according to preclinical and clinical research, and emphasize the heterogeneity and limitations of studies that have caused some controversies associated with this therapy. Overall, the role of thrombolytic therapy should not be overlooked. We anticipate that thrombolytic therapy combined with machine perfusion will provide an opportunity to improve inferior-quality DCD grafts, resulting in their becoming more widely available and safer for transplantation, thus solving the urgent problem of organ shortage.

Use of Ex Situ Machine Perfusion for Liver Transplantation: The National Experience

BACKGROUND

Machine perfusion (MP) for liver transplantation has become more widespread in the United States, but national studies on this growing practice are lacking. We investigated national use and outcomes of MP for liver transplantation.

METHODS

Adult (≥18 y) liver recipients transplanted between January 1, 2016 and September 30, 2023 in the United Network for Organ Sharing database were included. We used Cox regression to compare 1-y posttransplant recipient survival and all-cause graft failure by use of MP and performed subgroup analyses among circulatory death (DCD) and brain death (DBD) donors.

RESULTS

Of 52 626 deceased donors with liver recovery, 1799 (3.5%) utilized MP. The proportion of all liver transplants using MP increased from 0.3% in 2016 to 15.5% in 2023. MP for DCD transplants increased from 0.8% in 2016 to 50.0% in 2023. Donors of MP grafts were older (47 [34-57] versus 42 [29-55] y, P < 0.001), had higher body mass indexes (28.3 [24.4-33.3] versus 27.3 [23.7-31.8] kg/m2, P < 0.001), and were more likely to be DCD (47.1% versus 9.3%, P < 0.001). Among DBD transplants, MP and non-MP DBD transplants had similar all-cause graft failure out to 1 y (adjusted hazards ratios, 1.12 [95% confidence interval, 0.87-1.43], P = 0.38). Among DCD transplants, MP recipients had improved survival out to 1 y (adjusted hazards ratios, 0.50 [95% confidence interval, 0.35-0.70], P < 0.001).

CONCLUSIONS

MP use in liver transplantation is rapidly expanding and is associated with favorable outcomes compared with cold storage. MP is associated with increased posttransplant survival for DCD transplants, highlighting the potential for MP to expand utilization of DCD grafts.

Indocyanine green fluorescence quantification during normothermic ex situ perfusion for the assessment of porcine liver grafts after circulatory death

Current graft evaluation during normothermic ex situ liver perfusion lacks real-time parameters for predicting posttransplant hepatocyte and biliary function. Indocyanine green (ICG) imaging has been widely used in liver surgery, enabling the visualization of hepatic uptake and excretion through bile using near-infrared light. In this research, porcine livers under various ischemic conditions were examined during a 5-hour normothermic ex situ liver perfusion procedure, introducing ICG at 1 hour through the hepatic artery. These conditions included livers from heart-beating donors, donation after circulatory death (DCD) with warm ischemic durations of 60 minutes (DCD60) and 120 minutes (DCD120), as well as interventions utilizing tissue plasminogen activator in DCD120 cases (each n = 5). Distinct hepatic fluorescence patterns correlated with different degrees of ischemic injury ( p = 0.01). Low ICG uptake in the parenchyma (less than 40% of maximum intensity) was more prevalent in DCD120 (21.4%) compared to heart-beating donors (6.2%, p = 0.06) and DCD60 (3.0%, p = 0.02). Moreover, ICG clearance from 60 minutes to 240 minutes was significantly higher in heart-beating donors (69.3%) than in DCD60 (17.5%, p < 0.001) and DCD120 (32.1%, p = 0.01). Furthermore, thrombolytic intervention using tissue plasminogen activator in DCD120 resulted in noteworthy outcomes, including significantly reduced ALP levels ( p = 0.04) and improved ICG clearance ( p = 0.02) with a trend toward mitigating fibrin deposition similar to DCD60, as well as enhancements in bile production ( p = 0.09). In conclusion, ICG fluorescence imaging during normothermic ex situ liver perfusion provides real-time classification of hepatic vascular and biliary injuries, offering valuable insights for the more accurate selection and postintervention evaluation of marginal livers in transplantation.

A cost comparison of liver acquisition fees for donation after circulatory death versus donation after brain death donors

Donation after circulatory death (DCD) donors now represent over 30% of the deceased donor pool in the United States. Compared to donation after brain death, DCD is less likely to result in transplantation. For each potential donor whose organs cannot be utilized for transplantation (ie, dry run), fees are associated with the attempted donation, which add to the overall costs of organ acquisition. To better characterize the true costs of DCD liver acquisition, we performed a cost comparison of the fees associated with organ acquisition for DCD versus donation after brain death at a single transplant institute that comprises 2 liver transplant centers. Cost, recipient, and transportation data for all cases, including fees associated with liver acquisition from July 1, 2019, to October 31, 2021, were collected. We found that the total cost of DCD liver acquisition per liver transplant was $15,029 more than that for donation after brain death donation, with 18% of the costs of the DCD transplant attributed to dry runs. Overall, the costs associated with DCD transplantation accounted for 34.5% of the total organ acquisition costs; however, DCD transplantation accounted for 30.3% of the transplantation volume. Because the expansion of DCD is essential to increasing the availability of liver grafts for transplantation, strategies need to be implemented to decrease the costs associated with dry runs, including using local recovery, transferring donors to hospitals close to transplant centers, and performing more prerecovery organ analysis. Moreover, these strategies are needed to ensure that financial disincentives to DCD procurement and utilization do not reverse the gains made by expanding the organ donor pool using machine perfusion technologies.

Better liver transplant outcomes by donor interventions?

PURPOSE OF REVIEW

Donor risk factors and events surrounding donation impact the quantity and quality of grafts generated to meet liver transplant waitlist demands. Donor interventions represent an opportunity to mitigate injury and risk factors within donors themselves. The purpose of this review is to describe issues to address among donation after brain death, donation after circulatory determination of death, and living donors directly, for the sake of optimizing relevant outcomes among donors and recipients.

RECENT FINDINGS

Studies on donor management practices and high-level evidence supporting specific interventions are scarce. Nonetheless, for donation after brain death (DBD), critical care principles are employed to correct cardiocirculatory compromise, impaired tissue oxygenation and perfusion, and neurohormonal deficits. As well, certain treatments as well as marginally prolonging duration of brain death among otherwise stable donors may help improve posttransplant outcomes. In donation after circulatory determination of death (DCD), interventions are performed to limit warm ischemia and reverse its adverse effects. Finally, dietary and exercise programs have improved donation outcomes for both standard as well as overweight living donor (LD) candidates, while minimally invasive surgical techniques may offer improved outcomes among LD themselves.

SUMMARY

Donor interventions represent means to improve liver transplant yield and outcomes of liver donors and grafts.

Strategies to Improve the Utilization and Function of DCD Livers

Despite the increased usage of livers from donation after circulatory death (DCD) donors in the last decade, many patients remaining on the waitlist who need a liver transplant. Recent efforts have focused on maximizing the utilization and outcomes of these allografts using advances in machine perfusion technology and other perioperative strategies such as normothermic regional perfusion (NRP). In addition to the standard donor and recipient matching that is required with DCD donation, new data regarding the impact of graft steatosis, extensive European experience with NRP, and the increasing use of normothermic and hypothermic machine perfusion have shown immense potential in increasing DCD organ overall utilization and improved outcomes. These techniques, along with viability testing of extended criteria donors, have generated early promising data to consider the use of higher-risk donor organs and more widespread adoption of these techniques in the United States. This review explores the most recent international literature regarding strategies to optimize the utilization and outcomes of DCD liver allografts, including donor-recipient matching, perioperative strategies including NRP versus rapid controlled DCD recovery, viability assessment of discarded livers, and postoperative strategies including machine perfusion versus pharmacologic interventions.

Current Understanding of Marginal Grafts in Liver Transplantation

End-stage liver disease (ESLD), stemming from a spectrum of chronic liver pathologies including chronic liver failure, acute cirrhosis decompensation and hepatocellular carcinoma, imposes a significant global healthcare burden. Liver transplantation (LT) remains the only treatment for ESLD. However, the escalating mortality on transplant waitlists has prompted the utilization of marginal liver grafts in LT procedures. These grafts primarily encompass elderly livers, steatotic livers, livers from donation after circulatory death, split livers and those infected with the hepatitis virus. While the expansion of the donor pool offers promise, it also introduces concomitant risks. These encompass graft failure, biliary and cardiovascular complications, the recurrence of liver disease and reduced patient and graft survival. Consequently, various established strategies, ranging from improved donor-recipient matching to surgical interventions, have emerged to mitigate these risks. This article undertakes a comprehensive assessment of the current landscape, evaluating the viability of diverse marginal liver grafts. Additionally, it synthesizes approaches aimed at enhancing the quality of such marginal liver grafts. The overarching objective is to augment the donor pool and ameliorate the risk factors associated with the shortage of liver grafts.

Donation After Circulatory Death Liver Transplantation: Early Challenges, Clinical Improvement, and Future Directions

Donation after circulatory death (DCD) liver allografts remain a widely underutilized source of donor organs for transplantation. Although initially linked with inferior outcomes, DCD liver transplant can achieve excellent patient and graft survival with suitable matching of donor and recipient characteristics, rapid donor recovery and precise donor assessment, and appropriate perioperative management. The advent of clinical liver perfusion modalities promises to redefine the viability parameters for DCD liver allografts and hopefully will encourage more widespread usage of this growing source of donor livers.

Post-transplant outcomes and financial burden of donation after circulatory death donor liver transplant after the implementation of acuity circle policy

BACKGROUND

After implementation of the Acuity Circles (AC) allocation policy, use of DCD liver grafts has increased in the United States.

METHODS

We evaluated the impact of AC on rates of DCD-liver transplants (LT), their outcomes, and medical costs in a single practice. Adult LT patients were classified into three eras: Era 1 (pre-AC, 1/01/2015-12/31/2017); Era 2 (late pre-AC era, 1/01/2018-02/03/2020); and Era 3 (AC era, 05/10/2020-09/30/2021).

RESULTS

A total of 520 eligible LTs were performed; 87 were DCD, and 433 were DBD. With each successive era, the proportion of DCD increased (Era 1: 11%; Era 2: 20%; Era 3: 24%; p < .001). DCD recipients had longer ICU stays, higher re-admission/re-operation rates, and higher incidence of ischemic cholangiopathy compared to those with DBD. Direct, surgical, and ICU costs during first admission were higher with DCD than DBD (+8.0%, p < .001; +4.2%, p < .001; and +33.3%, p = .001). DCD-related costs increased after Era 1 (Direct: +4.9% [Era 2 vs. 1] and +12.4% [Era 3 vs. 1], p = .04; Surgical: +17.7% and +21.7%, p < .001). In the AC era, there was a significantly higher proportion of donors ≥50 years, and more national organ sharing. Compared to DCD from donors <50 years, DCD from donors ≥50 years was associated with significantly higher total direct, surgical, and ICU costs (+12.6%, p = .01; +9.5%, p = .01; +84.6%, p = .03).

CONCLUSIONS

The proportion of DCD-LT, especially from older donors, has increased after the implementation of AC policies. These changes are likely to be associated with higher costs in the AC era.

Impact of Median MELD at Transplant Minus 3 National Policy on Quality of Transplanted Livers for Patients With and Without Hepatocellular Carcinoma

BACKGROUND

Patients with hepatocellular carcinoma (HCC) have been overprioritized in the deceased donor liver allocation system. The United Network for Organ Sharing adopted a policy in May 2019 that limited HCC exception points to the median Model for End-Stage Liver Disease at transplant in the listing region minus 3. We hypothesized this policy change would increase the likelihood to transplant marginal quality livers into HCC patients.

METHODS

This was a retrospective cohort study of a national transplant registry, including adult deceased donor liver transplant recipients with and without HCC from May 18, 2017, to May 18, 2019 (prepolicy) to May 19, 2019, to March 1, 2021 (postpolicy). Transplanted livers were considered of marginal quality if they met ≥1 of the following: (1) donation after circulatory death, (2) donor age ≥70, (3) macrosteatosis ≥30% and (4) donor risk index ≥95th percentile. We compared characteristics across policy periods and by HCC status.

RESULTS

A total of 23 164 patients were included (11 339 prepolicy and 11 825 postpolicy), 22.7% of whom received HCC exception points (prepolicy versus postpolicy: 26.1% versus 19.4%; P = 0.03). The percentage of transplanted donor livers meeting marginal quality criteria decreased for non-HCC (17.3% versus 16.0%; P < 0.001) but increased for HCC (17.7% versus 19.4%; P < 0.001) prepolicy versus postpolicy. After adjusting for recipient characteristics, HCC recipients had 28% higher odds of being transplanted with marginal quality liver independent of policy period (odds ratio: 1.28; confidence interval, 1.09-1.50; P < 0.01).

CONCLUSIONS

The median Model for End-Stage Liver Disease at transplant in the listing region minus 3 policy limited exception points and decreased the quality of livers received by HCC patients.

Surgical Versus Image-Guided Interventions in the Management of Complications After Liver Transplantation

Liver transplantation is a technically demanding surgical procedure with known complications, and the optimal approach to addressing vascular and biliary complications requires a coordinated effort between surgical and interventional radiology teams. Vascular complications involving the hepatic artery, portal vein, or hepatic veins can be characterized by their mechanism, chronicity, and timing of presentation. These factors help determine whether the optimal therapeutic approach is surgical or endovascular. Very early presentation in the perioperative period favors surgical revision, while later presentation is best addressed endovascularly. Biliary complications can be categorized as leaks or strictures, and coordinated surgical, endoscopic, and percutaneous management is needed to address these types of complications. Through advances in technique and the management of complications, outcomes after liver transplantation continue to improve.

The yesterday, today and tomorrow of liver transplant

With a very long history of setbacks and successes, organ transplantation is one of the greatest medical achievements of the twentieth century. Liver transplantation is currently the most effective method for treating end-stage liver disease. From humble beginnings, improvements in surgical technique, perioperative management, and immunosuppressive therapy have yielded excellent graft and patient outcomes. Most established 'liver transplant' (LT) centres have a 1-year survival rate exceeding 90%, and a 3-year survival rate of over 80%. With immense success, the need for hepatic grafts substantially exceeds their availability. This problem has been partially addressed by using split grafts, living donor liver transplantation (LDLT), and extended criteria grafts (ECG). This article reviews the immense progress made in various aspects of LT including evaluation, increasing donor pool, surgical advances, immunosuppression and anaesthesia related aspects and the way forward. With ongoing cutting edge research in technologies like artificial liver devices, tissue bioengineering and hepatocyte 'farms', the future of LT is more exciting than ever before.

Evolving challenges with long-term care of liver transplant recipients

The number of liver transplants (LT) performed worldwide continues to rise, and LT recipients are living longer post-transplant. This has led to an increasing number of LT recipients requiring lifelong care. Optimal care post-LT requires careful attention to both the allograft and systemic issues that are more common after organ transplantation. Common causes of allograft dysfunction include rejection, biliary complications, and primary disease recurrence. While immunosuppression prevents rejection and reduces incidences of some primary disease recurrence, it has detrimental systemic effects. Most commonly, these include increased incidences of metabolic syndrome, various malignancies, and infections. Therefore, it is of utmost importance to optimize immunosuppression regimens to prevent allograft dysfunction while also decreasing the risk of systemic complications. Institutional protocols to screen for systemic disease and heightened clinical suspicion also play an important role in providing optimal long-term post-LT care. In this review, we discuss these common complications of LT as well as unique considerations when caring for LT recipients in the years after transplant.

Complications in Post-Liver Transplant Patients

Liver transplantation (LT) is the treatment of choice for liver failure and selected cases of malignancies. Transplantation activity has increased over the years, and indications for LT have been widened, leading to organ shortage. To face this condition, a high selection of recipients with prioritizing systems and an enlargement of the donor pool were necessary. Several authors published their case series reporting the results obtained with the use of marginal donors, which seem to have progressively improved over the years. The introduction of in situ and ex situ machine perfusion, although still strongly debated, and better knowledge and treatment of the complications may have a role in achieving better results. With longer survival rates, a significant number of patients will suffer from long-term complications. An extensive review of the literature concerning short- and long-term outcomes is reported trying to highlight the most recent findings. The heterogeneity of the behaviors within the different centers is evident, leading to a difficult comparison of the results and making explicit the need to obtain more consent from experts.

The evolution of the liver transplant candidate

The first successful human liver transplant (LT) was done over 60 years ago; since the early pioneering days, this procedure has become a routine treatment with excellent outcomes for the great majority of recipients. Over the last six decades, indications have evolved. Use of LT for hepatic malignancy is becoming less common as factors that define a successful outcome are being increasingly defined, and alternative therapeutic options become available. Both Hepatitis B and C virus associated liver disease are becoming less common indications as medical treatments become more effective in preventing end-stage disease. Currently, the most common indications are alcohol-related liver disease and metabolic associated liver disease. The developing (and controversial) indications include acute on chronic liver failure, alcoholic hepatitis and some rarer malignancies such as non-resectable colorectal cancer liver metastases, neuroendocrine tumours and cholangiocarcinoma. Candidates are becoming older and with greater comorbidities, A relative shortage of donor organs remains the greatest cause for reducing access to LT; therefore, various countries have developed transparent approaches to allocation of this life saving and life enhancing resource. Reliance on prognostic models has gone some way to improve transparency and increase equity of access but these approaches have their limitations.

Center expansion of liver transplants using donation after circulatory death organs is associated with reduced overall waitlist mortality

INTRODUCTION

Waitlist outcomes in liver transplantation (LT) for individual recipients are improved by use of allografts procured through donation after circulatory death (DCD). However, the impact of increased DCD acceptance on overall center outcomes is unknown.

METHODS

Using the United Network for Organ Sharing database, 88 centers performing an average of ≥10 LTs/year between 1/2004 and 12/2019 were compared by percent DCD use quartile and categorized into four phenotypes according to temporal usage trends. Overall center median Model for End-stage Liver Disease at LT (MMaT), waitlist mortality, and waiting time were evaluated.

RESULTS

The overall DCD rate was 6.1% (N = 4906/80,709), ranging from 0% to 25.5%. Centers in the top DCD use quartile had lower MMaT (24 vs. 26; p < .001) and shorter overall waiting times (median 66 days vs. 90 days; p < .001) compared to bottom quartile centers. MMaT increased less over time at centers with increasing DCD use and was lower than at centers with declining DCD use (27 vs. 32; p = .017). Overall waitlist mortality between 2016 and 2019 was lower at increasing DCD use centers (17.8% vs. 22.5%, p = .034), yet did not affect 1-year mortality (p = .747).

CONCLUSIONS

The improved waitlist outcomes at centers with expanded DCD use extend beyond DCD recipients alone without negative consequences to overall post-LT center metrics.

American Society of Transplant Surgeons recommendations on best practices in donation after circulatory death organ procurement

The American Society of Transplant Surgeons supports efforts to increase the number of organs that are critically needed for patients desperately awaiting transplantation. In the United States, transplantation using organs procured from donation after circulatory death (DCD) donors has continued to increase in number. Despite these increases, substantial variability in the utilization and practices of DCD transplantation still exists. To improve DCD organ utilization, it is important to create a set of best practices for DCD recovery. The following recommendations aim to provide guidance on contemporary issues surrounding DCD organ procurement in the United States. A work group was composed of members of the American Society of Transplant Surgeon Scientific Studies Committee and the Thoracic Organ Transplantation Committee. The following topics were identified by the group either as controversial or lacking standardization: prewithdrawal preparation, definition of donor warm ischemia time, DCD surgical technique, combined thoracic and abdominal procurements, and normothermic regional perfusion. The proposed recommendations were classified on the basis of the grade of available evidence and the strength of the recommendation. This information should be valuable for transplant programs as well as for organ procurement organizations and donor hospitals as they develop robust DCD donor procurement protocols.

Impact of Donor Liver Macrovesicular Steatosis on Deceased Donor Yield and Posttransplant Outcome

BACKGROUND

The Scientific Registry of Transplant Recipients (SRTR) had not traditionally considered biopsy results in risk-adjustment models, yet biopsy results may influence outcomes and thus decisions regarding organ acceptance.

METHODS

Using SRTR data, which includes data on all donors, waitlisted candidates, and transplant recipients in the United States, we assessed (1) the impact of macrovesicular steatosis on deceased donor yield (defined as number of livers transplanted per donor) and 1-y posttransplant graft failure and (2) the effect of incorporating this variable into existing SRTR risk-adjustment models.

RESULTS

There were 21 559 donors with any recovered organ and 17 801 liver transplant recipients included for analysis. Increasing levels of macrovesicular steatosis on donor liver biopsy predicted lower organ yield: ≥31% macrovesicular steatosis on liver biopsy was associated with 87% to 95% lower odds of utilization, with 55% of these livers being discarded. The hazard ratio for graft failure with these livers was 1.53, compared with those with no pretransplant liver biopsy and 0% to 10% steatosis. There was minimal change on organ procurement organization-specific deceased donor yield or program-specific posttransplant outcome assessments when macrovesicular steatosis was added to the risk-adjustment models.

CONCLUSIONS

Donor livers with macrovesicular steatosis are disproportionately not transplanted relative to their risk for graft failure. To avoid undue risk aversion, SRTR now accounts for macrovesicular steatosis in the SRTR risk-adjustment models to help facilitate use of these higher-risk organs. Increased recognition of this variable may also encourage further efforts to standardize the reporting of liver biopsy results.

The first successful report of liver transplantation from category III donation after circulatory death in South Korea: a case report

Deceased donor liver transplantation (DDLT) using donations after brain death (DBDs) has been widely performed in Korea. However, to date, there is no report regarding donation after circulatory death (DCD) category III. A 56-year-old male patient diagnosed with hepatitis B virus-associated liver cirrhosis underwent DDLT using DCD category III. The recipient's recovery was uneventful, and he was discharged on postoperative day 37. Currently, the patient is alive, with no complications 20 months after transplantation. This case suggests that DCD with LT is both feasible and safe. Further studies are required to validate this finding.

Comparison of Biliary Complications Rates After Brain Death, Donation After Circulatory Death, and Living-Donor Liver Transplantation: A Single-Center Cohort Study

Donation-after-circulatory-death (DCD), donation-after-brain-death (DBD), and living-donation (LD) are the three possible options for liver transplantation (LT), each with unique benefits and complication rates. We aimed to compare DCD-, DBD-, and LD-LT-specific graft survival and biliary complications (BC). We collected data on 138 DCD-, 3,027 DBD- and 318 LD-LTs adult recipients from a single center and analyzed patient/graft survival. BC (leak and anastomotic/non-anastomotic stricture (AS/NAS)) were analyzed in a subset of 414 patients. One-/five-year graft survival were 88.6%/70.0% for DCD-LT, 92.6%/79.9% for DBD-LT, and, 91.7%/82.9% for LD-LT. DCD-LTs had a 1.7-/1.3-fold adjusted risk of losing their graft compared to DBD-LT and LD-LT, respectively (p < 0.010/0.403). Bile leaks were present in 10.1% (DCD-LTs), 7.2% (DBD-LTs), and 36.2% (LD-LTs) (ORs, DBD/LD vs. DCD: 0.7/4.2, p = 0.402/<0.001). AS developed in 28.3% DCD-LTs, 18.1% DBD-LTs, and 43.5% LD-LTs (ORs, DBD/LD vs. DCD: 0.5/1.8, p = 0.018/0.006). NAS was present in 15.2% DCD-LTs, 1.4% DBDs-LT, and 4.3% LD-LTs (ORs, DBD/LD vs. DCD: 0.1/0.3, p = 0.001/0.005). LTs w/o BC had better liver graft survival compared to any other groups with BC. DCD-LT and LD-LT had excellent graft survival despite significantly higher BC rates compared to DBD-LT. DCD-LT represents a valid alternative whose importance should increase further with machine/perfusion systems.

DCD Liver Grafts Can Safely Be Used for Recipients With Grade I–II Portal Vein Thrombosis: A Multicenter Analysis

With donation after circulatory death (DCD) liver transplantation (LT), the goal of the recipient implantation procedure is to minimize surgical complexity to avoid a tenuous environment for an already marginal graft. The presence of portal vein thrombosis (PVT) at the time of LT adds surgical complexity, yet‚ to date, no studies have investigated the utilization of DCD liver grafts for patients with PVT.

Disparities in the Effects of Acuity Circle-based Liver Allocation on Waitlist and Transplant Practice Between Centers

Liver allocation in the United States was updated on February 4, 2020, by introducing the acuity circle (AC)-based model. This study evaluated the early effects of the AC-based allocation on waitlist outcomes.

Methods

Adult liver transplant (LT) candidates listed between January 1, 2019, and September 30, 2021, were assessed. Two periods were defined according to listing date (pre- and post-AC), and 90-d waitlist outcomes were compared. Median transplant Model for End-stage Liver Disease (MELD) score of each transplant center was calculated, with centers categorized as low- (<25 percentile), mid- (25-75 percentile), and high-MELD (>75 percentile) centers.

Results

A total of 12 421 and 17 078 LT candidates in the pre- and post-AC eras were identified. Overall, the post-AC era was associated with higher cause-specific 90-d hazards of transplant (csHR, 1.32; 95% confidence interval [CI], 1.27-1.38; P < 0.001) and waitlist mortality (cause-specific hazard ratio [csHR], 1.20; 95% CI, 1.09-1.32; P < 0.001). The latter effect was primarily driven by high-MELD centers. Low-MELD centers had a higher proportion of donations after circulatory death (DCDs) used. Compared with low-MELD centers, mid-MELD and high-MELD centers had significantly lower cause-specific hazards of DCD-LT in both eras (mid-MELD: csHR, 0.47; 95% CI, 0.38-0.59 in pre-AC and csHR, 0.56; 95% CI, 0.46-0.67 in post-AC and high-MELD: csHR, 0.11; 95% CI, 0.07-0.17 in pre-AC and csHR, 0.14; 95% CI, 0.10-0.20 in post-AC; all P < 0.001). Using a structural Bayesian time-series model, the AC policy was associated with an increase in the actual monthly DCD-LTs in low-, mid-, and high-MELD centers (actual/predicted: low-MELD: 19/16; mid-MELD: 21/14; high-MELD: 4/3), whereas the increase in monthly donation after brain death-LTs were only present in mid- and high-MELD centers.

Conclusions

Although AC-based allocation may improve waitlist outcomes, regional variation exists in the drivers of such outcomes between centers.

Does utilization of heart machine perfusion for donation after cardiac death transplantation affect outcomes of other abdominal transplanted organs?

INTRODUCTION

Machine perfusion of heart for donation after circulatory death (DCD) is being increasingly utilized. Current protocols for utilizing heart DCD's machine perfusion might prolong donor warm ischemic time for nonheart organs. The aim of this study was to analyze the effects of utilizing heart machine perfusion on liver and kidney transplants from the same donor.

METHODS

We analyzed data of DCD donors from the United Network for Organ Sharing (UNOS) from January-2020 to September-2021 among two groups: donors with heart machine perfusion (HM) and without heart machine perfusion (NHM). Propensity score (PS) matching was performed to compare the short-term outcomes of liver and kidney transplants between two groups.

RESULTS

Total of 102 liver and 319 kidney transplants were performed using organs from donors with HM. After PS matching, no statistically significant difference was seen in 1-year graft survival (GS) for both liver and kidney transplants between two groups (liver HM 90.6% vs. NHM 90.2%, p = .47; kidney HM 95.2% vs. NHM 92.9%, p = .40). There was no difference in the delayed graft function (DGF) rates in kidney transplantation (KT) (HM 42% vs. NHM 35%, p = .062).

CONCLUSION

Utilization of heart machine perfusion in DCD donors had no significant impact on 1-year outcomes of liver and kidney transplantation.

Classification of Distinct Patterns of Ischemic Cholangiopathy Following DCD Liver Transplantation: Distinct Clinical Courses and Long-term Outcomes From a Multicenter Cohort

BACKGROUND

As the number of donation after circulatory death (DCD) liver transplants (LTs) performed in the United States continues to increase annually, there has been interest by policy makers to develop a more robust exception point safety net for patients who develop ischemic cholangiopathy (IC) following DCD LT. As such, there is a need for better understanding of the clinical course and long-term outcomes in patients who develop IC, as well as determining if IC can be classified into distinct categories with distinctly different clinical outcomes.

METHODS

All DCD LT performed at Mayo Clinic Florida, Mayo Clinic Arizona, and Mayo Clinic Rochester from January 1999 to March 2020 were included (N = 770). Outcomes were compared between 4 distinct radiologic patterns of IC: diffuse necrosis, multifocal progressive, confluence dominant, and minor form.

RESULTS

In total, 88 (11.4%) patients developed IC, of which 42 (5.5%) were listed for retransplantation of liver (ReLT). Patients with diffuse necrosis and multifocal progressive patterns suffered from frequent hospital admissions for cholangitis in the first year following DCD LT (median 3 and 2), were largely stent dependent (100% and 85.7%), and almost universally required ReLT. Patients with confluence dominant disease were managed with multiple stents and frequently recovered, ultimately becoming stent free without need for ReLT. Patients with the minor form IC did well with limited need for stent placement or repeat procedures and did not require ReLT. Graft survival was different between the 4 distinct IC patterns (P < 0.001).

CONCLUSIONS

The present analysis provides a detailed analysis on the natural history and clinical course of IC. Patients developing IC can be classified into 4 distinct patterns with distinct clinical courses.

The volume - Outcomes relationship in donation after circulatory death liver transplantation

Background

Donation after circulatory death (DCD) liver transplantation (LT) has become an effective mechanism for expanding the donor pool and decreasing waitlist mortality. However, it is unclear if low‐volume DCD centers can achieve comparable outcomes to high‐volume centers.

Methods

From 2011 to 2019 utilizing the United Network for Organ Sharing (UNOS) database, liver transplant centers were categorized into tertiles based on their annual volume of DCD LTs. Donor selection, recipient selection, and survival outcomes were compared between very‐low volume (VLV, n = 1–2 DCD LTs per year), low‐volume (LV, n = 3–5), and high‐volume (HV, n > 5) centers.

Results

One hundred and ten centers performed 3273 DCD LTs. VLV‐centers performed 339 (10.4%), LV‐centers performed 627 (19.2%), and HV‐centers performed 2307 (70.4%) LTs. 30‐day, 90‐day, and 1‐year patient and graft survival were significantly increased at HV‐centers (all P < .05). Recipients at HV‐centers had shorter waitlist durations (P < .01) and shorter hospital lengths of stay (P < .01). On multivariable regression, undergoing DCD LT at a VLV‐center or LV‐center was associated with increased 1‐year patient mortality (VLV‐OR:1.73, 1.12–2.69) (LV‐OR: 1.42, 1.01–2.00) and 1‐year graft failure (VLV‐OR: 1.79, 1.24–2.58) (LV‐OR: 1.28, .95–1.72).

Discussion

Increased annual DCD liver transplant volume is associated with improved patient and graft survival.

Safely Expanding the Liver Donor Pool by Utilization of Organs from Donation after Circulatory Death with Comparable Results to Donation After Brain Death, a Large Single-Center Experience

BACKGROUND

Use of livers donated after circulatory death (DCD) is one way to expand the donor pool. Our center has aggressively incorporated use of DCD liver grafts into practice. We examined our center and national outcomes as well as national DCD liver utilization.

METHODS

Liver transplants performed at our center and nationally from 11/2016 through 9/2020 were compared. Primary outcomes were patient and graft survival, and national DCD liver utilization.

RESULTS

For our center, DCD and donation after brain death (DBD) donors were similar except DCD donors were younger (37 vs 40 years; p < 0.05). Recipient Na-MELD (20 vs 24; p < 0.0001) and cold ischemia time (4.63 vs 5.18 h; p < 0.05) were lower in DCD recipients. There were no significant differences in 1-year patient and graft survival between DCD and DBD liver recipients locally. Nationally, there was a difference in 1-year graft survival year (89.4% vs 92.4%, p < 0.0001) but patient survival was similar between groups. The proportion of DCD livers recovered and transplanted widely varied among organ procurement organizations (OPOs) and transplant centers.

CONCLUSIONS

Similar outcomes for DCD and DBD liver recipients should encourage centers and OPOs nationwide to expand utilization of DCD livers.

Ischemic Cholangiopathy Postdonation After Circulatory Death Liver Transplantation: Donor Hepatectomy Time Matters

Background.

Outcomes of liver transplantation (LT) from donation after circulatory death (DCD) have been improving; however, ischemic cholangiopathy (IC) continues to be a problem. In 2014, measures to minimize donor hepatectomy time (DHT) and cold ischemic time (CIT) have been adopted to improve DCD LT outcomes.

Methods.

Retrospective review of all patients who underwent DCD LT between 2005 and 2017 was performed. We compared outcomes of patients who were transplanted before 2014 (historic group) with those who were transplanted between 2014 and 2017 (modern group).

Results.

We identified 112 patients; 44 were in the historic group and 68 in the modern group. Donors in the historic group were younger (26.5 versus 33, P = 0.007) and had a lower body mass index (26.2 versus 28.2, P = 0.007). DHT (min) and CIT (h) were significantly longer in the historic group (21.5 versus 14, P < 0.001 and 5.3 versus 4.2, P < 0.001, respectively). Fourteen patients (12.5%) developed IC, with a significantly higher incidence in the historic group (23.3% versus 6.1%, P = 0.02). There was no difference in graft and patient survival between both groups.

Conclusion.

In appropriately selected recipients, minimization of DHT and CIT may decrease the incidence of IC. These changes can potentially expand the DCD donor pool.

Antemortem Heparin in Organ Donation After Circulatory Death Determination: A Systematic Review of the Literature

Donation after circulatory death determination frequently involves antemortem heparin administration to mitigate peri-arrest microvascular thrombosis. We systematically reviewed the literature to: (1) describe heparin administration practices and (2) explore the effects on transplant outcomes. We searched MEDLINE and EMBASE for studies reporting donation after circulatory death determination heparin practices including use, dosage, and timing (objective 1). To explore associations between antemortem heparin and transplant outcomes (objective 2), we (1) summarized within-study comparisons and (2) used meta-regression analyses to examine associations between proportions of donors that received heparin and transplant outcomes. We assessed risk of bias using the Newcastle Ottawa Scale and applied the GRADE methodology to determine certainty in the evidence. For objective 1, among 55 eligible studies, 48 reported heparin administration to at least some donors (range: 15.8%-100%) at variable doses (up to 1000 units/kg) and times relative to withdrawal of life-sustaining therapy. For objective 2, 7 studies that directly compared liver transplants with and without antemortem heparin reported lower rates of primary nonfunction, hepatic artery thrombosis, graft failure at 5 y, or recipient mortality (low certainty of evidence). In contrast, meta-regression analysis of 32 liver transplant studies detected no associations between the proportion of donors that received heparin and rates of early allograft dysfunction, primary nonfunction, hepatic artery thrombosis, biliary ischemia, graft failure, retransplantation, or patient survival (very low certainty of evidence). In conclusion, antemortem heparin practices vary substantially with an uncertain effect on transplant outcomes. Given the controversies surrounding antemortem heparin, clinical trials may be warranted.

Similar Results in Liver Transplantation From Controlled Donation After Circulatory Death Donors With Normothermic Regional Perfusion and Donation After Brain Death Donors: A Case-Matched Single-Center Study

Although good results have been reported with the use of normothermic regional perfusion (NRP) in controlled donation after circulatory death (cDCD) liver transplantation (LT), there is a lack of evidence to demonstrate similar results to donation after brain death (DBD). We present a single-center retrospective case-matched (1:2) study including 100 NRP cDCD LTs and 200 DBD LTs and a median follow-up of 36 months. Matching was done according to donor age, recipient Model for End-Stage Liver Disease score, and cold ischemia time. The following perioperative results were similar in both groups: alanine transaminase peaks of 909 U/L in the DBD group and 836 U/L in the cDCD group and early allograft disfunction percentages of 21% and 19.2%, respectively. The 1-year and 3-year overall graft survival for cDCD was 99% and 93%, respectively, versus 92% and 87%, respectively, for DBD (P = 0.04). Of note, no cases of primary nonfunction or ischemic-type biliary lesion were observed among the cDCD grafts. Our results confirm that NRP cDCD LT meets the same outcomes as those obtained with DBD LT and provides evidence to support the idea that cDCD donors per se should no longer be considered as "marginal donors" when recovered with NRP.

Thromboelastography profiles for controlled circulatory death donors: Validating the role of heparin

Controlled donation after circulatory death (cDCD) liver transplants are associated with increased ischemic-type biliary complications. Microvascular thrombosis secondary to decreased donor fibrinolysis may contribute to bile duct injury. We hypothesized that cDCD donors are hypercoagulable with impaired fibrinolysis and aim to use thromboelastography to characterize cDCD coagulation profiles.

Recommendations for Donor and Recipient Selection and Risk Prediction: Working Group Report From the ILTS Consensus Conference in DCD Liver Transplantation

Although the utilization of donation after circulatory death donors (DCDs) for liver transplantation (LT) has increased steadily, much controversy remains, and no common acceptance criteria exist with regard to donor and recipient risk factors and prediction models. A consensus conference was organized by International Liver Transplantation Society on January 31, 2020, in Venice, Italy, to review the current clinical practice worldwide regarding DCD-LT and to develop internationally accepted guidelines. The format of the conference was based on the grade system. International experts in this field were allocated to 6 working groups and prepared evidence-based recommendations to answer-specific questions considering the currently available literature. Working group members and conference attendees served as jury to edit and confirm the final recommendations presented at the end of the conference by each working group separately. This report presents the final statements and recommendations provided by working group 2, covering the entire spectrum of donor and recipient risk factors and prediction models in DCD-LT.

Early Allograft Dysfunction and Complications in DCD Liver Transplantation: Expert Consensus Statements From the International Liver Transplantation Society

Livers for transplantation from donation after circulatory death donors are relatively more prone to early and ongoing alterations in graft function that might ultimately lead to graft loss and even patient death. In consideration of this fact, this working group of the International Liver Transplantation Society has performed a critical evaluation of the medical literature to create a set of statements regarding the assessment of early allograft function/dysfunction and complications arising in the setting of donation after circulatory death liver transplantation.

Regulations and Procurement Surgery in DCD Liver Transplantation: Expert Consensus Guidance From the International Liver Transplantation Society

Donation after circulatory death (DCD) donors are an increasingly more common source of livers for transplantation in many parts of the world. Events that occur during DCD liver recovery have a significant impact on the success of subsequent transplantation. This working group of the International Liver Transplantation Society evaluated current evidence as well as combined experience and created this guidance on DCD liver procurement. Best practices for the recovery and transplantation of livers arising through DCD after euthanasia and organ procurement with super-rapid cold preservation and recovery as well as postmortem normothermic regional perfusion are described, as are the use of adjuncts during DCD liver procurement.

Conditional probability of graft survival in liver transplantation using donation after circulatory death grafts - a retrospective study

The use of livers from donation after circulatory death (DCD) is historically characterized by increased rates of biliary complications and inferior short-term graft survival (GS) compared to donation after brain death (DBD) allografts. This study aimed to evaluate the dynamic prognostic impact of DCD livers to reveal whether they remain an adverse factor even after patients survive a certain period following liver transplant (LT). This study used 74 961 LT patients including 4065 DCD LT in the scientific registry of transplant recipients from 2002-2017. The actual, 1 and 3-year conditional hazard ratio (HR) of 1-year GS in DCD LT were calculated using a conditional version of Cox regression model. The actual 1-, 3-, and 5-year GS of DCD LT recipients were 83.3%, 73.3%, and 66.3%, which were significantly worse than those of DBD (all P < 0.01). Actual, 1-, and 3-year conditional HR of 1-year GS in DCD compared to DBD livers were 1.87, 1.49, and 1.39, respectively. Graft loss analyses showed that those lost to biliary related complications were significantly higher in the DCD group even 3 years after LT. National registry data demonstrate the protracted higher risks inherent to DCD liver grafts in comparison to their DBD counterparts, despite survival through the early period after LT. These findings underscore the importance of judicious DCD graft selection at individual center level to minimize the risk of long-term biliary complications.

Cholangiocyte Epithelial to Mesenchymal Transition (EMT) is a potential molecular mechanism driving ischemic cholangiopathy in liver transplantation

Donation after circulatory death (DCD) has expanded the donor pool for liver transplantation. However, ischemic cholangiopathy (IC) after DCD liver transplantation causes inferior outcomes. The molecular mechanisms of IC are currently unknown but may depend on ischemia-induced genetic reprograming of the biliary epithelium to mesenchymal-like cells. The main objective of this study was to determine if cholangiocytes undergo epithelial to mesenchymal transition (EMT) after exposure to DCD conditions and if this causally contributes to the phenotype of IC. Human cholangiocyte cultures were exposed to periods of warm and cold ischemia to mimic DCD liver donation. EMT was tested by assays of cell migration, cell morphology, and differential gene expression. Transplantation of syngeneic rat livers recovered under DCD conditions were evaluated for EMT changes by immunohistochemistry. Human cholangiocytes exposed to DCD conditions displayed migratory behavior and gene expression patterns consistent with EMT. E-cadherin and CK-7 expressions fell while N-cadherin, vimentin, TGFβ, and SNAIL rose, starting 24 hours and peaking 1-3 weeks after exposure. Cholangiocyte morphology changed from cuboidal (epithelial) before to spindle shaped (mesenchymal) a week after ischemia. These changes were blocked by pretreating cells with the Transforming Growth Factor beta (TGFβ) receptor antagonist Galunisertib (1 μM). Finally, rats with liver isografts cold stored for 20 hours in UW solution and exposed to warm ischemia (30 minutes) at recovery had elevated plasma bilirubin 1 week after transplantation and the liver tissue showed immunohistochemical evidence of early cholangiocyte EMT. Our findings show EMT occurs after exposure of human cholangiocytes to DCD conditions, which may be initiated by upstream signaling from autocrine derived TGFβ to cause mesenchymal specific morphological and migratory changes.

Thrombolytic Therapy During ex-vivo Normothermic Machine Perfusion of Human Livers Reduces Peribiliary Vascular Plexus Injury

Background: A major limitation in expanding the use of donation after circulatory death (DCD) livers in transplantation is the increased risk of graft failure secondary to ischemic cholangiopathy. Warm ischemia causes thrombosis and injury to the peribiliary vascular plexus (PVP), which is supplied by branches of the hepatic artery, causing higher rates of biliary complications in DCD allografts.

Aims/Objectives: We aimed to recondition discarded DCD livers with tissue plasminogen activator (tPA) while on normothermic machine perfusion (NMP) to improve PVP blood flow and reduce biliary injury.

Methods: Five discarded DCD human livers underwent 12 h of NMP. Plasminogen was circulated in the base perfusate prior to initiation of perfusion and 1 mg/kg of tPA was administered through the hepatic artery at T = 0.5 h. Two livers were split prior to perfusion (S1, S2), with tPA administered in one lobe, while the other served as a control. The remaining three whole livers (W1-W3) were compared to seven DCD control liver perfusions (C1-C7) with similar hepatocellular and biliary viability criteria. D-dimer levels were measured at T = 1 h to verify efficacy of tPA. Lactate, total bile production, bile pH, and difference in biliary injury scores before and after perfusion were compared between tPA and non-tPA groups using unpaired, Mann-Whitney tests.

Results: Average weight-adjusted D-dimer levels were higher in tPA livers in the split and whole-liver model, verifying drug function. There were no differences in perfusion hepatic artery resistance, portal vein resistance, and arterial lactate between tPA livers and non-tPA livers in both the split and whole-liver model. However, when comparing biliary injury between hepatocellular and biliary non-viable whole livers, tPA livers had significantly lower PVP injury scores (0.67 vs. 2.0) and mural stroma (MS) injury scores (1.3 vs. 2.7).

Conclusion: This study demonstrates that administration of tPA into DCD livers during NMP can reduce PVP and MS injury. Further studies are necessary to assess the effect of tPA administration on long term biliary complications.

Comparable graft survival is achievable with the usage of donation after circulatory death liver grafts from donors at or above 70 years of age: A long-term UK national analysis

The aim of the study was to assess the UK donation after circulatory death (DCD) liver transplant experience from donors ≥70 years. Nationwide UK DCD retrospective analysis was conducted between 2001 and 2015 (n = 1163). Recipients were divided into group 1 vs. group 2 (donors 70≥ vs. <70 years, respectively). group 1 (n = 69, 5.9%) recipients were older (median 59 vs. 55 years, p = .001) and had longer waitlist time (128 vs. 84 days; p = .039). 94.2% of group 1 clustered in London and Birmingham, where the two busiest centers are located. group 1 allografts had higher UKDRI and UK DCD Risk Scores but similar WIT and CIT and were more likely to have been imported. Both groups had similar 1-, 3-, and 5-year graft survival (group 1, 90%, 81.4%, and 74% vs. group 2, 88.6%, 81.4%, and 78.6%, respectively; p = .54). Both groups had similar ICU stay length (p = .22), 3-month hepatic artery thrombosis rates (4.4% vs 4.0%; p = .9), and 12-month readmission rates for all biliary complications (20.3% vs 25.7%; p = .32). This study demonstrates that acceptable outcomes are achievable using older grafts in a highly selected cohort at experienced centers. Advanced age should not be an absolute contraindication to utilizing a DCD graft from donors aged ≥70 years.

Donation After Circulatory Death Yields Survival Rates Similar to Donation After Brain Death Liver Transplant, Which Effectively Expands the Donor Pool

OBJECTIVES

Liver allograft shortage has necessitated greater use of donations after circulatory death. Limited data are available to compare recipients' health care utilization for donation after circulatory death versus brain death.

MATERIALS AND METHODS

Liver transplant data for our center from November 2016 until May 2019 were obtained (208 donations after brain death and 39 after circulatory death). We excluded patients <18 years old and multiorgan transplants; for cost data only, we also excluded retransplants. Primary outcome was recipients' health care utilization in donation after circulatory death versus brain death and included index admission length of stay, readmissions, and charges from transplant to 6 months. Secondary outcomes were patient and graft survival.

RESULTS

Donors from circulatory death were younger than donors from brain death (median age 32 vs 40 years; P < .01). Recipient body mass index (31.23 vs 29.38 kg/m2), Model for End-Stage Liver Disease score (17 vs 19), portal vein thrombosis (15.8% vs 18.0%), length of stay (7 vs 8 days), and 30-, 90-, and 180-day posttransplant index admissions were not significantly different. Charges for index admission were equivalent for donation after circulatory death ($370771) and brain death ($374272) (P = .01). Charges for readmissions at 30 and 180 days were not significantly different (P = .80 and P = .19, respectively). Rates for graft failure (10.3% vs 4.8%; P = .08) and recipient death (10.3% vs 3.8%; P = .17) at 6 months posttransplant were similar.

CONCLUSIONS

Donation after circulatory death versus brain death liver transplant recipients had similar lengths of stay and equivalent index admission charges. Graft and patient survival and charges from transplant to 6 months were similar. Donation after circulatory death liver allografts provide a safe, costequivalent donor pool expansion after careful donorrecipient selection.

Donation after circulatory death liver transplantation: An in-depth analysis and propensity score-matched comparison

BACKGROUND

Careful donor-recipient matching and reduced ischemia times have improved outcomes following donation after circulatory death (DCD) liver transplantation (LT). This study examines a single-center experience with DCD LT including high-acuity and hospitalized recipients.

METHODS

DCD LT outcomes were compared to a propensity score-matched (PSM) donation after brain death (DBD) LT cohort (1:4); 32 DCD LT patients and 128 PSM DBD LT patients transplanted from 2008 to 2018 were included. Analyses included Kaplan-Meier estimates and Cox proportional hazards models examining patient and graft survival.

RESULTS

Median MELD score in the DCD LT cohort was 22, with median MELD of 27 for DCD LT recipients with decompensated cirrhosis. No difference in mortality or graft loss was found (p < .05) between DCD LT and PSM DBD LT at 3 years post-transplant, nor was DCD an independent risk factor for patient or graft survival. Post-LT severe acute kidney injury was similar in both groups. Ischemic-type biliary lesions (ITBL) occurred in 6.3% (n = 2) of DCD LT recipients, resulting in 1 graft loss and 1 death.

CONCLUSION

This study supports that DCD LT outcomes can be similar to DBD LT, with a low rate of ITBL, in a cohort including high-acuity recipients. Strict donor selection criteria, ischemia time minimization, and avoiding futile donor/recipient combinations are essential considerations.

Evolving utilization of donation after circulatory death livers in liver transplantation: The day of DCD has come

Compared to donation after brain death (DBD), livers procured for transplantation from donation after circulatory death (DCD) donors experience more ischemia-reperfusion injury and higher rates of ischemic cholangiopathy due to the period of warm ischemic time (WIT) following withdrawal of life support. As a result, utilization of DCD livers for liver transplant (LT) has generally been limited to short WITs and younger aged donor grafts, causing many recovered DCD organs to be discarded without consideration for transplant. This study assesses how DCD liver utilization and outcomes have changed over time, using OPTN data from adult, first-time, deceased donor, whole-organ LTs between January 1995 and December 2019. Results show that increased clinical experience with DCD LT has translated into increased use of livers from DCD donors, shorter ischemic times, shorter lengths of hospitalization after transplant, and lower rates of retransplantation. The data also reveal that over the past decade, the rate of increase in DCD LTs conducted in the United States has outpaced that of DBD. Together, these trends signal an opportunity for the field of liver transplantation to mitigate the organ shortage by capitalizing on DCD liver allografts that are currently not being utilized.

Expanding Role of Donation After Circulatory Death Donors in Liver Transplantation

Better understanding of how to utilize donation after circulatory death (DCD) liver grafts has resulted in improved national outcomes and expansion in the number of DCD liver transplants (LTs). This improvement has been driven by better donor and recipient matching, careful evaluation of hemodynamics during withdrawal of life support, and refinement of the procurement operation. Changes to liver allocation likely will result in increased utilization of DCD liver grafts. Ischemic cholangiopathy remains the Achilles heel of DCD LTs and, although rates have fallen with improved protocols, a certain rate likely is unavoidable. This review discusses contemporary issues with DCD LTs.

Simultaneous liver-kidney transplantation from donation after cardiac death donors: an updated perspective

Outcomes of both donation after cardiac death (DCD) liver and kidney transplants are improving. Experience in simultaneous liver-kidney transplant (SLK) using DCD donors, however, remains limited. In an updated cohort (2010-2018), outcomes of 30 DCD SLK and 131 donation after brain death (DBD) SLK from Mayo Clinic Arizona and Mayo Clinic Minnesota were reviewed. The Model for End-Stage Liver Disease score was lower in the DCD SLK group (23 vs 29, P = .01). Kidney delayed graft function (DGF) rates were similar between the 2 groups (P = .11), although the duration of DGF was longer for DCD SLK recipients (20 vs 4 days, P = .01). Liver allograft (93.3% vs 93.1%, P = .29), kidney allograft (93.3% vs 93.1%, P = .91), and patient (96.7% vs 95.4%, P = .70) 1-year survival rates were similar. At 1 year, there were no differences in the estimated glomerular filtration rate (57.7 ± 18.2 vs 56.3 ± 17.7, P = .75) or progression of fibrosis (ci) on protocol kidney biopsy (P = .67). A higher incidence of biliary complications was observed in the DCD SLK group, with ischemic cholangiopathy being the most common (10.0% vs 0.0%, P = .03). The majority of biliary complications resolved with endoscopic management. With appropriate selection, DCD SLK recipients can have results equivalent to those of DBD SLK recipients.

Donation after circulatory death liver transplantation: What are the limits for an acceptable DCD graft?

The utilization of donation after circulatory death (DCD) livers has been growing over the last decade. In large-volume centers, survival outcomes have improved and are comparable to outcomes with brain death donor (DBD) liver transplantation (LT). The relatively concentrated success with DCD LT demonstrated by high-volume transplant centers has rekindled international enthusiasm. The combination of increasing expertise in DCD LT and ongoing shortage in transplantable organs has promoted expansion of the DCD donor pool with regards to donor age, body mass index and donor warm ischemia time. In this review, we focused on the practice patterns in DCD liver graft utilization in the last decade, along with the possibilities for further expansion of DCD liver graft utilization and new technologies, such as machine perfusion.

Biliary complications in donation after circulatory death liver transplantation: the Australian National Liver Transplantation Unit's experience

BACKGROUND

Biliary complications are the most common complications of donation after circulatory death (DCD) liver transplantation and the international experience with DCD transplants suggests increased rates of biliary complications compared to donation after brain death transplants. Therefore, it is important to understand factors that are associated with the development of biliary complications within the Australian DCD context in order to inform future practice. The aim of this study is to determine the incidence of biliary complications after DCD liver transplantation at the Australian National Liver Transplantation Unit and identify factors associated with this outcome.

METHODS

A retrospective analysis of all adult DCD liver transplants at the Australian National Liver Transplantation Unit from 2007 to 2015 was undertaken. The primary outcome measure was the incidence of biliary complications and was censored on 31 December 2016. Recipients were then stratified into groups based on the development of biliary complications and risk factor analysis was performed.

RESULTS

Biliary complications occurred in 35% of DCD transplants, including seven anastomotic strictures and 10 non-anastomotic strictures. Higher donor risk index scores (P = 0.03), post-transplant portal vein complications (P = 0.042) and peak gamma-glutamyl transferase levels within 7 days post-transplant (P = 0.047) were associated with biliary complications.

CONCLUSION

Findings from this study demonstrate that biliary complications remain common in DCD liver recipients. Recipients who developed a biliary complication tended to have higher donor risk index, elevated peak gamma-glutamyl transferase levels within 7 days post-transplant or a portal vein complication. The presence of any of these factors should prompt close monitoring for post-transplant biliary complications.

Perioperative and long-term outcomes of utilizing donation after circulatory death liver grafts with macrosteatosis: A multicenter analysis

BACKGROUND

Given the potentially additive risk from using donor livers that are both steatotic and from a donation after circulatory death (DCD) donor, there is a paucity of data on the outcome of DCD liver transplantation (LT) utilizing livers with macrosteatosis.

METHODS

All DCD LT performed at Mayo Clinic-Florida, Mayo Clinic-Arizona, and Mayo Clinic-Rochester from 1999 to 2019 were included (N = 714). Recipients of DCD LT were divided into 3 groups: those with moderate macrosteatosis (30%-60%), mild macrosteatosis (5%-30%), and no steatosis (<5%).

RESULTS

Patients with moderate macrosteatosis had a higher rate of postreperfusion syndrome (PRS; 53.9% vs 26.2%; P = .002), postreperfusion cardiac arrest (7.7% vs 0.3%; P < .001), primary nonfunction (PNF; 7.7% vs 1.0%; P = .003), early allograft dysfunction (EAD; 70.8% vs 45.6% and 8.3%; P = .02), and acute kidney injury (AKI; 39.1% vs 19.4%; P = .02) than patients with no steatosis. No difference in any of the perioperative complications was seen between the mild macrosteatosis and the no steatosis groups except for the rate of EAD (56.8% vs 45.6%; P = .04). No difference in ischemic cholangiopathy (IC), vascular thrombosis/stenosis or graft, and patient survival was seen between the 3 groups.

CONCLUSION

DCD donors with mild macrosteatosis < 30% can be utilized with no increase in perioperative complications and similar patient and graft survival compared to DCD donors with no steatosis. When utilizing DCD donors with moderate macrosteatosis higher rates of PRS, PNF, postreperfusion cardiac arrest, EAD, and AKI should be anticipated.