Marginal Liver Research Articles

Effects of machine perfusion strategies on different donor types in liver transplantation: a systematic review and meta-analysis.

The increasing use of extended criteria donors (ECD) sets higher requirements for graft preservation. Machine perfusion (MP) improves orthotopic liver transplantation (OLT) outcomes, but its effects on different donor types remains unclear. The authors' aim was to assess the effects of hypothermic machine perfusion (HMP), normothermic machine perfusion (NMP), or normothermic regional perfusion (NRP) versus static cold storage (SCS) on different donor types. A literature search comparing the efficacy of MP versus SCS in PubMed, Cochrane, and EMBASE database was conducted. A meta-analysis was performed to obtain pooled effects of MP on ECD, donation after circulatory death (DCD), and donor after brainstem death. Thirty nine studies were included (nine randomized controlled trials and 30 cohort studies). Compared with SCS, HMP significantly reduced the risk of non-anastomotic biliary stricture (NAS) [odds ratio (OR) 0.43, 95% confidence interval (CI) 0.26-0.72], major complications (OR 0.55, 95% CI 0.39-0.78), and early allograft dysfunction (EAD) (OR 0.46, 95% CI 0.32-0.65) and improved 1-year graft survival (OR 2.36, 95% CI 1.55-3.62) in ECD-OLT. HMP also reduced primary non-function (PNF) (OR 0.40, 95% CI 0.18-0.92) and acute rejection (OR 0.62, 95% CI 0.40-0.97). NMP only reduced major complications in ECD-OLT (OR 0.56, 95% CI 0.34-0.94), without favorable effects on other complications and survival. NRP lowered the overall risk of NAS (OR 0.27, 95% CI 0.11-0.68), PNF (OR 0.43, 95% CI 0.22-0.85), and EAD (OR 0.58, 95% CI 0.42-0.80) and meanwhile improved 1-year graft survival (OR 2.40, 95% CI 1.65-3.49) in control DCD-OLT. HMP might currently be considered for marginal livers as it comprehensively improves ECD-OLT outcomes. NMP assists some outcomes in ECD-OLT, but more evidence regarding NMP-ECD is warranted. NRP significantly improves DCD-OLT outcomes and is recommended where longer non-touch periods exist.

Non-invasive evaluation of hepatic macrosteatosis in deceased donors

IntroductionLiver allocation changes have led to increased travel and expenditures, highlighting the need to efficiently identify marginal livers suitable for transplant. We evaluated the validity of existing non-invasive liver quality tests and a novel machine learning-based model at predicting deceased donor macrosteatosis >30%. MethodsWe compared previously-validated non-invasive tests and a novel machine learning-based model to biopsies in predicting macrosteatosis >30%. We also tested them in populations enriched for macrosteatosis. ResultsThe Hepatic Steatosis Index area-under-the-curve (AUC) was 0.56. At the threshold identified by Youden's J statistic, sensitivity, specificity, positive, and negative predictive values were 49.6%, 58.9%, 14.0%, and 89.7%. Other tests demonstrated comparable results. Machine learning produced the highest AUC (0.71). Even in populations enriched for macrosteatosis, no test was sufficiently predictive. ConclusionCommonly used clinical scoring systems and a novel machine learning-based model were not clinically useful, highlighting the importance of pre-procurement biopsies to facilitate allocation.

Video-assisted transthoracic liver resection in patients with marginal liver function: A retrospective cohort study

Video-assisted transthoracic liver resection in patients with marginal liver function: A retrospective cohort study

The Current Role and Future Applications of Machine Perfusion in Liver Transplantation.

The relative paucity of donor livers suitable for transplantation has sparked innovations to preserve and recondition organs to expand the pool of transplantable organs. Currently, machine perfusion techniques have led to the improvement of the quality of marginal livers and to prolonged cold ischemia time and have allowed for the prediction of graft function through the analysis of the organ during perfusion, improving the rate of organ use. In the future, the implementation of organ modulation might expand the scope of machine perfusion beyond its current usage. The aim of this review was to provide an overview of the current clinical use of machine perfusion devices in liver transplantation and to provide a perspective for future clinical use, including therapeutic interventions in perfused donor liver grafts.

Carving Out The Future of Marginal Liver Rescue With Normothermic Machine Preservation.

Olumba, Franklin C MD; Zhou, Fangyu MD PhD; Doyle, Majella MB MD MBA FACS; Vachharajani, Neeta MS; Upadhya, Gundumi A PhD; Park, Yikyung ScD; Chapman, William C MD FACS Author Information

Nanoparticle-Based Interventions for Liver Transplantation.

Liver transplantation is the only treatment for hepatic insufficiency as a result of acute and chronic liver injuries/pathologies that fail to recover. Unfortunately, there remains an enormous and growing gap between organ supply and demand. Although recipients on the liver transplantation waitlist have significantly higher mortality, livers are often not allocated because they are (i) classified as extended criteria or marginal livers and (ii) subjected to longer cold preservation time (>6 h) with a direct correlation of poor outcomes with longer cold ischemia. Downregulating the recipient's innate immune response to successfully tolerate a graft having longer cold ischemia times or ischemia-reperfusion injury through induction of immune tolerance in the graft and the host would significantly improve organ utilization and post-transplant outcomes. Broadly, technologies proposed for development aim to extend the life of the transplanted liver through post-transplant or recipient conditioning. In this review, we focus on the potential benefits of nanotechnology to provide unique pre-transplant grafting and recipient conditioning of extended criteria donor livers using immune tolerance induction and hyperthermic pre-conditioning.

N-acetylcysteine and Reduction of Ischemia-reperfusion Injury in Liver Transplantation.

In the current issue of Transplantation, Jia et al perform a systemic review and meta-analysis looking at the utilization of N-acetylcysteine (NAC) in the donor and recipient in liver transplantation.1,2 It has been suggested that NAC may have a role in mitigating ischemia-reperfusion injury that occurs during the various stages of organ donation. The pathophysiology of ischemia-reperfusion injury is mainly due to the oxidative stress and cytotoxicity arising from the imbalance between oxidants and antioxidants. NAC is a rich source of sulfhydryl groups, which are important for replenishing glutathione (GSH) stores. GSH acts as a free radical scavenger to decrease damage caused by the toxic free radicals. GSH is the main endogenous antioxidant, and the liver is the main organ producing GSH under normal conditions.2 The present meta-analysis demonstrates a lower incidence of primary nonfunction, a reduction in posttransplant peak aspartate transaminase and alanine transaminase, and reduced postoperative complications in the NAC treatment groups compared with the control groups. As a long-time proponent of the use of NAC in the transplant setting, the overall results of this meta-analysis are encouraging. At Mayo Clinic Florida, we routinely use a NAC infusion for donation after circulatory death (DCD) liver transplant recipients. Our protocol involves a bolus of 150 mg/kg given over 1 h before reperfusion followed by an infusion of 150 mg/kg given for 72 h. Our current rate of ischemic cholangiopathy is <4%; however, whether NAC provides any direct benefit in the reduction of ischemic cholangiopathy remains unproven.3 More recently, we have also started using NAC in the perfusate when performing abdominal normothermic regional perfusion in DCD donors ([6 g/30 mL] × 3 vials). Negative effects of NAC administration are minimal. Although the meta-analysis demonstrated a slightly increased need for packed red blood cells and cryoprecipitate in NAC treatment groups, the magnitude of difference was <1 unit. This may imply that although a statistically significant difference was seen, such a small difference may not be clinically significant. There are some limitations to the present study that should be mentioned. One of the challenges with combining the data from the different studies in the present analysis is that some of the studies gave NAC to the donors at the time of donor procurement, some gave NAC to the recipients at the time of transplant, and others gave NAC to both the donor and recipient. Dosing and timing of dosing was also very heterogeneous between the different studies. Given this heterogeneity, developing a comprehensive protocol utilizing NAC is problematic. In the subanalysis, the authors did suggest that NAC administration to the recipient appeared to produce better clinical effects than administration to the donor. Another unanswered question based on the present analysis is how the benefits of NAC may vary by donor type? Some of the studies looked at living donors while others looked at donation after brain death donors and others looked at DCD donors. Could there be a more significant effect in marginal liver grafts with a suspected higher degree of ischemia-reperfusion injury or should NAC be utilized in all cases? Finally postoperative complications were treated as a binary variable (yes/no) for the analysis. Given the vastly different implications of complications based on their severity, using a classification system such as Clavien-Dindo would be more meaningful when comparing study groups. Despite the limitations of the present meta-analysis, the results are encouraging and suggest that NAC does have some potentially beneficial effects in reducing ischemia-reperfusion injury when used in the setting of liver transplantation. The adequate safety of NAC, in addition to its low costs, makes it an appealing intervention. Further studies are needed before evidence is strong enough to recommend a specific protocol describing both optimal timing and dosage for administration. Moreover, the donor type that may achieve the greatest benefit remains unknown.

Xenogeneic cross-circulation for physiological support and recovery of ex vivo human livers.

The scarcity of suitable donor livers highlights a continuing need for innovation to recover organs with reversible injuries in liver transplantation. Explanted human donor livers (n = 5) declined for transplantation were supported using xenogeneic cross-circulation of whole blood between livers and xeno-support swine. Livers and swine were assessed over 24 hours of xeno-support. Livers maintained normal global appearance, uniform perfusion, and preservation of histologic and subcellular architecture. Oxygen consumption increased by 75% ( p = 0.16). Lactate clearance increased from -0.4 ± 15.5% to 31.4 ± 19.0% ( p = 0.02). Blinded histopathologic assessment demonstrated improved injury scores at 24 hours compared with 12 hours. Vascular integrity and vasoconstrictive function were preserved. Bile volume and cholangiocellular viability markers improved for all livers. Biliary structural integrity was maintained. Xenogeneic cross-circulation provided multisystem physiological regulation of ex vivo human livers that enabled functional rehabilitation, histopathologic recovery, and improvement of viability markers. We envision xenogeneic cross-circulation as a complementary technique to other organ-preservation technologies in the recovery of marginal donor livers or as a research tool in the development of advanced bioengineering and pharmacologic strategies for organ recovery and rehabilitation.

Discussion.

Journal of the American College of Surgeons 236(4):p 625-629, April 2023. | DOI: 10.1097/XCS.0000000000000595

Applicability of the histidine-tryptophan-ketoglutarate solution as a machine perfusion solution for marginal liver grafts.

There are very few reports comparing the use of the University of Wisconsin solution and histidine-tryptophan-ketoglutarate solution as machine perfusion solutions for marginal liver grafts. We aimed to clarify whether the use of the histidine-tryptophan-ketoglutarate solution in hypothermic machine perfusion improves the split-liver graft function in a large animal model. Porcine split-liver grafts were created by 75% liver resection. Hypothermic machine perfusion experimental groups were divided as follows: Group 1, perfusate, University of Wisconsin gluconate solution (UW group; n=5), and Group 2, perfusate, histidine-tryptophan-ketoglutarate solution (HTK group; n=4). After 4h of preservation, the liver function was evaluated using an isolated liver reperfusion model for 2h. In the HTK group, the portal vein and hepatic artery resistance during hypothermic machine perfusion and the portal vein resistance during isolated liver reperfusion were lower than those in the UW group. In addition, the total Suzuki score for hepatic ischemia-reperfusion injury in the HTK group was significantly better than that in the UW group. The number of anti-ETS-related genes staining-positive sinusoid epithelial cell nuclei in the HTK group was higher than that in the UW group (not significant). The histidine-tryptophan-ketoglutarate solution can be perfused with lower vascular resistance than the University of Wisconsin solution, reducing shear stress and preventing sinusoid epithelial cell injury in marginal grafts used as split-liver grafts.

Vitamin A Intake and Status Influence Retinol Balance, Utilization and Dynamics in Rats ,

To study effects of vitamin A status on retinol dynamics, male rats were fed purified diets varying in vitamin A concentration. Group 1 rats had marginal liver vitamin A levels (approximately 500 nmol) and were in a slight positive vitamin A balance; Group 2 had similar liver levels but were in a slight negative balance; Group 3 had lower liver levels (approximately 370 nmol) and were in a slight negative balance; Group 4 had depleted liver reserves (<10 nmol) and were in vitamin A balance. [3H]Retinol-labeled plasma was injected intravenously, and serial plasma samples were collected for 41 d while rats (six per group) consumed approximately 50 nmol retinol/d (Group 1) or -25 nmol/d (Groups 2-4). Plasma retinol was normal in Groups 1-3 (1.9-2.0 micromol/L) and lower in Group 4 (0.96 micromol/L). Plasma tracer data were fit to a three-compartment model. The central plasma retinol compartment (transit time, 1.5-1.7 h) exchanged with a fast turning-over extravascular vitamin A pool (transit time, 3-4.5 h; -40 nmol) and with a larger, slow turning-over extravascular pool (transit time, 5.5-10 d) that was the site of irreversible utilization of vitamin A. Irreversible utilization was 36 nmol/d (Group 1), 29 nmol/d (Groups 2 and 3) and 20 nmol/d (Group 4). The data indicate that in rats with low or marginal vitamin A status, vitamin A intake, vitamin A reserves and plasma retinol concentration all influence vitamin A utilization and other aspects of retinol dynamics.

Acuity circles allocation policy impact on waitlist mortality and donation after circulatory death liver transplantation: A nationwide retrospective analysis.

Acuity circles allocation policy impact on waitlist mortality and donation after circulatory death liver transplantation: A nationwide retrospective analysis.

Normothermic Machine Perfusion for Declined Livers: A Strategy to Rescue Marginal Livers for Transplantation.

Organ waste is a major cause of the donor liver shortage. Roughly 67% of recovered organ donors have liver utilization annually. A new technology called normothermic machine perfusion (NMP) offers a way to recover marginal and declined livers for transplant. We report interim results of the RESTORE trial (FDA investigational drug exemption trial NCT04483102) that aims to transplant NMP-treated livers that would otherwise be discarded. Declined livers were screened for NMP eligibility (eg donation after circulatory death [DCD] grafts with warm ischemic time <40 minutes, donation after brain death [DBD] grafts with cold ischemic time <8 hours). Livers meeting pre-NMP eligibility criteria received NMP using the OrganOx metra device for a minimum of 4 hours. All NMP-treated livers meeting the viability criteria were transplanted to consented recipients. Over 22 months, 60 declined livers from three organ procurement organizations (OPOs; 40 DCD and 20 DBD donor livers) were offered, and 22 livers (10 DCD and 12 DBD livers) met the pre-NMP eligibility. After NMP, 16 of 22 livers passed viability testing and were transplanted into needy recipients (median Model for End-Stage Liver Disease [MELD] score of 8, range 6 to 24), resulting in a 72.7% rescue rate (50% DCD, 91.7% DBD). The rate of early allograft dysfunction was 31.3%, but there were no graft-related deaths, primary nonfunction, or instances of nonanastomotic biliary strictures. Interim results of the RESTORE trial suggest that a sizable number of declined livers can be reclaimed. They are safe for transplantation and can enable lower MELD patients at high risk of morbidity and mortality to receive lifesaving grafts while offering OPOs a way to allocate more livers and reduce organ waste.

Enhancing the accuracy of mid-infrared spectroscopy-based liver steatosis quantification using digital image analysis as a reference.

The assessment of liver steatosis is crucial in both hepatology and liver transplantation (LT) surgery. Steatosis can negatively impact the success of LT. Steatosis is a factor for excluding donated organs for LT, but the increasing demand for transplantable organs has led to the use of organs from marginal donors. The current standard for evaluating steatosis is a semi-quantitative grading based on the visual examination of a hematoxylin and eosin (H&E)-stained liver biopsy, but this method is time-consuming, subjective, and lacks reproducibility. Recent research has shown that infrared (IR) spectroscopy could be used as a real-time quantitative tool to assess steatosis during abdominal surgery. However, the development of IR-based methods has been hindered by the lack of appropriate quantitative reference values. In this study, we developed and validated digital image analysis methods for the quantitation of steatosis in H&E-stained liver sections using univariate and multivariate strategies including linear discriminant analysis (LDA), quadratic DA, logistic regression, partial least squares-DA (PLS-DA), and support vector machines. The analysis of 37 tissue samples with varying grades of steatosis demonstrates that digital image analysis provides accurate and reproducible reference values that improve the performance of IR spectroscopic models for steatosis quantification. A PLS model in the 1810-1052 cm-1 region using first derivative ATR-FTIR spectra provided RMSECV = 0.99%. The gained improvement in accuracy critically enhances the applicability of Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) to support an objective graft evaluation at the operation room, which might be especially relevant in cases of marginal liver donors to avoid unnecessary graft explantation.

What Is the Optimal Preservation Strategy of Marginal Liver Grafts Using Hypothermic Oxygenated Perfusion? A Preclinical Study

What Is the Optimal Preservation Strategy of Marginal Liver Grafts Using Hypothermic Oxygenated Perfusion? A Preclinical Study

A Meta-Analysis and Systematic Review of Normothermic and Hypothermic Machine Perfusion in Liver Transplantation

The gap between the demand and supply of donor livers is still a considerable challenge. Since static cold storage is not sufficient in marginal livers, machine perfusion is being explored as an alternative. The objective of this study was to assess (dual) hypothermic oxygenated machine perfusion (HOPE/D-HOPE) and normothermic machine perfusion (NMP) in contrast to static cold storage (SCS). Three databases were searched to identify studies about machine perfusion. Graft and patient survival and postoperative complications were evaluated using the random effects model. the incidence of biliary complications was lower in HOPE vs. SCS (OR: 0.59, 95% CI: 0.36-0.98, p = 0.04, I2: 0%). There was no significant difference in biliary complications between NMP and SCS (OR: 0.76, 95% CI: 0.41-1.40, p = 0.38, I2: 55%). Graft and patient survival were significantly better in HOPE than in SCS (HR: 0.40, 95% CI: 0.23-0.71, p = 0.002, I2: 0%) and (pooled HR: 0.43, 95% CI: 0.20-0.93, p = 0.03, I2: 0%). Graft and patient survival were not significantly different between NMP and SCS. HOPE/D-HOPE and NMP are promising alternatives to SCS for donor liver preservation. They may help address the widening gap between the demand for and availability of donor livers by enabling the rescue and transplantation of marginal livers.

Tumor Size and Dose Impact Recurrence after Stereotactic Body Radiotherapy (SBRT) for Liver Metastases (LM) from Colorectal Cancer (CRC)

<h3>Purpose/Objective(s)</h3> SBRT is used to treat LM from CRC. Prior studies demonstrate acceptable in-field control (IFC) but have limited evaluation of treatment characteristics. We sought to determine the effect of tumor and treatment-related variables. <h3>Materials/Methods</h3> We reviewed an IRB-approved prospectively collected database of SBRT treatments between 2013-2021 at an NCI-designated comprehensive cancer center. Post-SBRT MRI every 3-4 months was fused with RT plan and evaluated for in-field (IFR), marginal (MR), and regional (RR) liver recurrences. MR = low dose region adjacent to high dose region. RR = elsewhere in liver. Retreated lesions were excluded. Tumor and dosimetric variables were compared by lesion recurrence status using Wilcoxon rank sum tests and Fisher exact tests. IFC (time to IFR) and IFC/MC (time to IFR or MR) were evaluated using Kaplan Meier methods with log rank tests and/or Cox proportional hazards methods using within-patient robust standard errors. <h3>Results</h3> The study included 33 patients with 41 lesions. Most (72%) were metastatic at presentation and had a single lesion treated (n=25), while the remaining had 2 treated simultaneously (n=5) or sequentially (n=3). Median age was 59 years (34-88). Median tumor volume was 35.5 cc, with 25 (61%) from 10 to 50 cc. Median total dose (TD) was 55 Gy (24-60 Gy) in 5 fractions (3-5); 19 lesions (46%) received 60 Gy. Median follow-up was 18.4 months in those who died (n=10) and 20.2 in those alive (n=13). IFR and MR were diagnosed in 7 (17%) and 4 (9%) lesions, respectively. Nineteen (46%) had RR. 1-year IFC was 86% (CI 70-94). IFR was associated with lower median TD (45 vs 60 Gy; p=0.008), biologically effective dose (BED) (85 vs 132; p=0.008), prescription isodose line (IDL) (68.0 vs 77.7%; p=0.007), and larger tumor size (155 vs 30.8 cc; p=0.002). Differences were maintained when comparing lesions with either IFR or MR vs. neither. IFC was better for smaller tumors, with 1-year rate of 96% (CI 73-99) for tumors <50 cc compared to 70% (CI 37-87) for ≥50 cc (p=0.005). TD of 50-60 Gy had better 1-year IFC of 96% vs 64% for 24-47.5 Gy (p<0.001). Higher IDL also had better 1-year IFC (86% for 80-85.7 vs 83% for 70-79 vs. 33% for 63.3-69.5; p=0.048). Occurrence of either IFR or MR was higher at TD 24-55 Gy vs. 60 Gy (41% vs 10%; p=0.006), with IFC/MC at 1-year of 65% vs 94% (p=0.006). Using Cox models, IFR/MR was also higher at larger tumor size (HR 11.08; p=0.001) and IDL (for 1% difference, HR 0.91; p=0.008). Estimated IFC/MC is 80% (CI 62-90) at 1 year vs 69% (CI 49-82) at 2 years. <h3>Conclusion</h3> IFC after SBRT for LM in CRC was excellent with 50 to 60 Gy. Higher BED and TD reduced IFR and MR after SBRT for liver metastases. Larger tumor size yielded a higher failure rate and may warrant additional dose. Although durable IFC is frequently achieved, there are opportunities for intensifying therapy.

Marginal donor liver versus standard donor liver: A single-center observational study

BackgroundThe effectiveness and safety of marginal donor livers remain controversial. This study aimed to investigate the clinical efficacy of marginal donor livers in patients with liver transplantation (LT). MethodsThis study included 199 liver donors (including 16 split donors) and 206 liver recipients from January 1, 2018 to January 27, 2020, with case follow-up until July 31, 2021. Clinical data of donors and recipients were retrospectively analyzed and were divided into the marginal donor and standard donor groups according to the criteria of marginal donor livers. Indices of liver and kidney functions, complications, and survival curves of the two groups were compared. ResultsCompared with the standard donor group, the blood creatinine levels were significantly higher in the marginal donor group in the first week after operation (P < 0.05); there were no significant differences in alanine aminotransferase, aspartate aminotransferase, and total bilirubin levels after LT (all P > 0.05); there was no significant difference in the incidence of complications after LT (P > 0.05); there was also no significant difference in the survival curve (P = 0.335). ConclusionsThere were no significant differences in liver and kidney function and survival curve between the standard donor and marginal donor groups. The marginal donor liver appears safe and reliable for LT and may be an important strategy to expand the donor pool and solve the shortage of organs.

Interleukin-18 and High-Mobility-Group-Protein B1 are Early and Sensitive Indicators for Cell Damage During Normothermic Machine Perfusion after Prolonged Cold Ischemic Storage of Porcine Liver Grafts.

In the era of organ machine perfusion, experimental models to optimize reconditioning of (marginal) liver grafts are needed. Although the relevance of cytokine signatures in liver transplantation has been analyzed previously, the significance of molecular monitoring during normothermic machine perfusion (NMP) remains elusive. Therefore, we developed a porcine model of cold ischemic liver graft injury after prolonged static cold storage (SCS) and subsequent NMP: Livers obtained from ten minipigs underwent NMP for 6h directly after procurement (control group) or after 20h of SCS. Grafts after prolonged SCS showed significantly elevated AST, ALT, GLDH and GGT perfusate concentrations, and reduced lactate clearance. Bile analyses revealed reduced bile production, reduced bicarbonate and elevated glucose concentrations after prolonged SCS. Cytokine analyses of graft perfusate simultaneously demonstrated an increase of pro-inflammatory cytokines such as Interleukin-1α, Interleukin-2, and particularly Interleukin-18. The latter was the only significantly elevated cytokine compared to controls, peaking as early as 2h after reperfusion (11,012ng/ml vs. 1,493ng/ml; p = 0.029). Also, concentrations of High-Mobility-Group-Protein B1 were significantly elevated after 2h of reperfusion (706.00ng/ml vs. 148.20ng/ml; p < 0.001) and showed positive correlations with AST (r 2 = 0.846) and GLDH (r 2 = 0.918) levels. Molecular analyses during reconditioning of liver grafts provide insights into the degree of inflammation and cell damage and could thereby facilitate future interventions during NMP reducing acute and chronic graft injury.

No Stone Left Unturned: Utilization of an Organ Procurement Organization Donor Surgeon at Procurement Reduces Discards of Marginal Liver Allografts.

The recent trend of organ procurement organizations (OPOs) employing independent surgeons for organ procurement has been developed with the goal of improving the supply of suitable organs for transplantation. We investigated the effects that the addition of an OPO-employed, organ-procurement specialist has on liver allograft discard rate, marginal organ utilization, and graft survival. Organ Procurement and Transplant Network and OPO data were retrospectively studied between April 1, 2014' and July 31, 2019' within the Southwest Transplant Alliance donor service area. Liver procurements with an OPO-surgeon present (OPO-Present) were compared to those without the involvement of an OPO surgeon (OPO-Absent). Donor and recipient characteristics as well as outcomes were analyzed across groups using propensity score matching. In total 869 OPO-Present liver allografts had similar rates of discard (5.2%) compared to 771 OPO-Absent livers (5.8%). However, after adjusting for donor risk, OPO-Present livers had a lower propensity of discard compared to OPO-Absent (3.4% versus 7.6%, P < 0.05). OPO-Present livers were more likely to be shared nationally (11.0% versus 4.8%, P < 0.001). Outcome analysis showed allograft survival of OPO-Present livers at 5 y was comparable to OPO-Absent livers (79.5% versus 80%, P = 0.34). The presence of an OPO surgeon was associated with decreased liver allograft discard and increased utilization of marginal donor organs. The OPO surgeon's presence represents a potential strategy to increase organ utilization nationally.