Expanding Role of Donation After Circulatory Death Donors in Liver Transplantation

Transplant center variability in utilizing nonstandard donors and its impact on the transplantation of patients with lower MELD scores

There is a subset of patients with lower MELD scores who are at substantial risk of waitlist mortality. In order to transplant such patients, transplant centers must utilize "nonstandard" donors (eg, living donors, donation after circulatory death), which are traditionally offered to those patients who are not at the top of the waitlist. We used Organ Procurement and Transplantation data to evaluate center-level and region-level variability in the utilization of nonstandard donors and its impact on MELD at transplant among adult liver-alone non-status 1 patients transplanted from April 1, 2020, to September 30, 2022. The center-level variability in the utilization of nonstandard donors was 4-fold greater than the center-level variability in waitlisting practices (waitlistings with a MELD score of <20). While there was a moderate correlation between center-level waitlisting and transplantation of patients with a MELD score of <20 ( p = 0.58), there was a strong correlation between center-level utilization of nonstandard donors and center-level transplantation of patients with a MELD score of <20 ( p = 0.75). This strong correlation between center-level utilization of "nonstandard" donors and center-level transplantation of patients with a MELD score of <20 was limited to regions 2, 4, 5, 9, and 11. Transplant centers that utilize more nonstandard donors are more likely to successfully transplant patients at lower MELD scores. Public reporting of these data could benefit patients, caregivers, and referring providers, and be used to help maximize organ utilization.

Outcomes of liver transplantation for hepatocellular carcinoma in donation after circulatory death compared with donation after brain death: A systematic review and meta-analysis

INTRODUCTION AND OBJECTIVES

Due to organ shortages, liver transplantation (LT) using donation-after-circulatory-death (DCD) grafts has become more common. There is limited and conflicting evidence on LT outcomes using DCD grafts compared to those using donation-after-brain death (DBD) grafts for patients with hepatocellular carcinoma (HCC). We aimed to summarize the current evidence on the outcomes of DCD-LT and DBD-LT in patients with HCC.

MATERIALS AND METHODS

Online databases were searched for studies comparing DCD-LT and DBD-LT outcomes in patients with HCC and a meta-analysis was conducted using fixed- or random-effects models.

RESULTS

Five studies involving 487 (33.4%) HCC DCD-LT patients and 973 (66.6%) DBD-LT patients were included. The meta-analysis showed comparable 1-year [relative risk (RR)=0.99, 95%CI:0.95 to 1.03, p=0.53] and 3-year [RR=0.99, 95%CI:0.89 to 1.09, p=0.79] recurrence-free survival. The corresponding 1-year [RR=0.98, 95%CI:0.93 to 1.03, p=0.35] and 3-year [RR=0.94, 95%CI:0.87 to 1.01, p=0.08] patient survival and 1-year [RR=0.91, 95%CI:0.71 to 1.16, p=0.43] and 3-year [RR=0.92, 95%CI:0.67 to 1.26, p=0.59] graft survival were also comparable. There were no significant differences between the two cohorts regarding the tumor characteristics, donor/recipient risk factors and the incidence of post-operative complications, including acute rejection, primary non-function, biliary complications and retransplantation.

CONCLUSIONS

Based on the current evidence, it has been found that comparable outcomes can be achieved in HCC patients using DCD-LT compared to DBD-LT, particularly when employing good quality graft, strict donor and recipient selection, and effective surgical management. The decision to utilize DCD-LT for HCC patients should be personalized, taking into consideration the risk of post-LT HCC recurrence. (PROSPERO ID: CRD42023445812).

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.

Impact of the donor hepatectomy time on short-term outcomes in liver transplantation using donation after circulatory death: A review of the US national registry

BACKGROUND

During the donor hepatectomy time (dHT), defined as the time from the start of cold perfusion to the end of the hepatectomy, liver grafts have a suboptimal temperature. The aim of this study was to analyze the impact of prolonged dHT on outcomes in donation after circulatory death (DCD) liver transplantation (LT).

METHODS

Using the US national registry data between 2012 and 2020, DCD LT patients were separated into 2 groups based on their dHT: standard dHT (<42 min) and prolonged dHT (≥42 min).

RESULTS

There were 3810 DCD LTs during the study period. Median dHT was 32 min (IQR 25-41 min). Kaplan- Meier graft survival curves demonstrated inferior outcomes in the prolonged dHT group at 1-year after DCD LT compared to those in the standard dHT group (85.3% vs 89.9%; p < 0.01). Multivariate Cox proportional hazards models for 1-year graft survival identified that prolonged dHT [hazard ratio (HR) 1.46, 95% confidence interval (CI) 1.19 - 1.79], recipient age ≥ 64 years (HR 1.40, 95% CI 1.14 - 1.72), and MELD score ≥ 24 (HR 1.43, 95% CI 1.16 - 1.76) were significant predictors of 1-year graft loss. Spline analysis shows that the dHT effects on the risk for 1-year graft loss with an increase in the slope after median dHT of 32 min.

CONCLUSION

Prolonged dHTs significantly reduced graft and patient survival after DCD LT. Because dHT is a modifiable factor, donor surgeons should take on cases with caution by setting the dHT target of < 32 min. This article is protected by copyright. All rights reserved.

The Implication of Center Volumes in Donation After Circulatory Death for Liver Transplantation: Donor-Recipient Selection and Outcomes

BACKGROUND

The use of donation after circulatory death liver transplant (DCD LT) has increased and the outcomes have improved. There are little data concerning the details of centers' practice.

METHODS

Using the United Network for Organ Sharing Standard Transplant Analysis and Research data, the centers were stratified into 4 quartiles: lowest-, low-, high-, and highest-volume quartiles.

RESULTS

High-risk donors, defined as older donors (≥50 years) or obese donors (body mass index ≥ 30 kg/m²), linearly increased in line with the centers' volumes (P < .001), while cold ischemia time (CIT) showed an inverse correlation (P < .001). High-risk recipients, defined as those with high Model for End-stage Liver Disease score, re-LT, inpatient, or ventilator/dialysis before LT, did not show any significant difference (P = .74) except in the highest-volume quartile (P < .001). One-year graft survival showed a bimodal pattern across the 4 quartiles (P = .027): superior graft survival in the highest-volume quartile and in the low-volume quartile and inferior graft survival in the high-volume quartile and in the lowest-volume quartile.

CONCLUSIONS

High-risk donors can achieve satisfactory outcomes by being matched with low-risk recipients and shortening CIT. However, high-risk recipients may not result in favorable outcomes with DCD LT even with centers' experience and shorter CIT.

National experience with living donor liver transplantation for hepatocellular carcinoma

Living donor liver transplantation (LDLT) is an attractive option to decrease waitlist dropout, particularly for patients with hepatocellular carcinoma (HCC) who face lengthening waiting times. Using the United Network for Organ Sharing (UNOS) national database, trends in LDLT utilization for patients with HCC were evaluated, and post-LT outcomes for LDLT versus deceased donor liver transplantation (DDLT) were compared. From 1998 to 2018, LT was performed in 20,161 patients with HCC including 726 (3.6%) who received LDLT. The highest LDLT utilization was prior to the 2002 HCC Model for End-Stage Liver Disease (MELD) exception policy (17.5%) and dropped thereafter (3.1%) with a slight increase following the 6-month wait policy in 2015 (3.8%). LDLT was more common in patients from long-wait UNOS regions with blood type O, in those with larger total tumor diameter (2.3 vs. 2.1 cm, p = 0.02), and higher alpha-fetoprotein at LT (11.5 vs. 9.0 ng/ml, p = 0.04). The 5-year post-LT survival (LDLT 77% vs. DDLT 75%), graft survival (72% vs. 72%), and HCC recurrence (11% vs. 13%) were similar between groups (all p > 0.20). In conclusion, LDLT utilization for HCC has remained low since 2002 with only a slight increase after the 6-month wait policy introduction in 2015. Given the excellent post-LT survival, LDLT appears to be an underutilized but valuable option for patients with HCC, especially those at high risk for waitlist dropout.

Early United States experience with liver donation after circulatory determination of death using thoraco-abdominal normothermic regional perfusion: A multi-institutional observational study

Mortality on the liver waitlist remains unacceptably high. Donation after circulatory determination of death (DCD) donors are considered marginal but are a potentially underutilized resource. Thoraco-abdominal normothermic perfusion (TA-NRP) in DCD donors might result in higher quality livers and offset waitlist mortality. We retrospectively reviewed outcomes of the first 13 livers transplanted from TA-NRP donors in the US. Nine centers transplanted livers from 8 organ procurement organizations. Median donor age was 25 years; median agonal phase was 13 minutes. Median recipient age was 60 years; median lab MELD score was 21. Three patients (23%) met early allograft dysfunction (EAD) criteria. Three received simultaneous liver-kidney transplants; neither had EAD nor delayed renal allograft function. One recipient died 186 days post-transplant from sepsis but had normal pre-sepsis liver function. One patient developed a biliary anastomotic stricture, managed endoscopically; no recipient developed clinical evidence of ischemic cholangiopathy (IC). Twelve of 13 (92%) patients are alive with good liver function at 439 days median follow-up; 1 patient has extrahepatic recurrent HCC. TA-NRP DCD livers in these recipients all functioned well, particularly with respect to IC, and provide a valuable option to decrease deaths on the waiting list. This article is protected by copyright. All rights reserved.