A multicenter randomized-controlled trial of hypothermic oxygenated perfusion (HOPE) for human liver grafts before transplantation

BACKGROUND & AIMS

Machine perfusion is a novel method intended to optimize livers before transplantation. However, its effect on morbidity within a 1-year period after transplantation has remained unclear.

METHODS

In this multicenter controlled trial, we randomly assigned livers donated after brain death (DBD) for liver transplantation (LT). Livers were either conventionally cold stored (control group), or cold stored and subsequently treated by 1-2 h hypothermic oxygenated perfusion (HOPE) before implantation (HOPE group). The primary endpoint was the occurrence of at least one post-transplant complication per patient, graded by the Clavien score of ≥III, within 1-year after LT. The comprehensive complication index (CCI), laboratory parameters, as well as duration of hospital and intensive care unit stay, graft survival, patient survival, and biliary complications served as secondary endpoints.

RESULTS

Between April 2015 and August 2019, we randomized 177 livers, resulting in 170 liver transplantations (85 in the HOPE group and 85 in the control group). The number of patients with at least one Clavien ≥III complication was 46/85 (54.1%) in the control group and 44/85 (51.8%) in the HOPE group (odds ratio 0.91; 95% CI 0.50-1.66; p = 0.76). Secondary endpoints were also not significantly different between groups. A post hoc analysis revealed that liver-related Clavien ≥IIIb complications occurred less frequently in the HOPE group compared to the control group (risk ratio 0.26; 95% CI 0.07-0.77; p = 0.027). Likewise, graft failure due to liver-related complications did not occur in the HOPE group, but occurred in 7% (6 of 85) of the control group (log-rank test, p = 0.004, Gray test, p = 0.015).

CONCLUSIONS

HOPE after cold storage of DBD livers resulted in similar proportions of patients with at least one Clavien ≥III complication compared to controls. Exploratory findings suggest that HOPE decreases the risk of severe liver graft-related events.

IMPACT AND IMPLICATIONS

This randomized controlled phase III trial is the first to investigate the impact of hypothermic oxygenated perfusion (HOPE) on cumulative complications within a 12-month period after liver transplantation. Compared to conventional cold storage, HOPE did not have a significant effect on the number of patients with at least one Clavien ≥III complication. However, we believe that HOPE may have a beneficial effect on the quantity of complications per patient, based on its application leading to fewer severe liver graft-related complications, and to a lower risk of liver-related graft loss. The HOPE approach can be applied easily after organ transport during recipient hepatectomy. This appears fundamental for wide acceptance since concurring perfusion technologies need either perfusion at donor sites or continuous perfusion during organ transport, which are much costlier and more laborious. We conclude therefore that the post hoc findings of this trial should be further validated in future studies.

Gunshot wound versus blunt liver injuries: different liver-related complications and outcomes

PURPOSE

Severe hepatic injury due to gunshot (GSW) compared to blunt mechanism may have significantly different presentation, management, complications, and outcomes. The aim of this study was to identify the differences.

METHODS

Retrospective single-center analysis June 1, 2015-June 30, 2020, included all patients with Grade III-V liver injuries due to GSW or blunt mechanism. Clinical characteristics, severity of injury, liver-related complications (rebleeding, necrosis/abscess, bile leak/biloma, pseudoaneurysm, acute liver failure) and overall outcomes (mortality, hospital length of stay, intensive care unit length of stay, and ventilatory days) were compared.

RESULTS

Of 879 patients admitted with hepatic trauma, 347 sustained high-grade injury and were included: 81 (23.3%) due to GSW and 266 (76.7%) due to blunt force. A significantly larger proportion of patients with GSW were managed operatively (82.7 vs. 36.1%, p < 0.001). GSW was associated with significantly more liver-related complications (40.7% vs. 27.4%, p = 0.023), specifically liver necrosis/abscess (18.5% vs. 7.1%, p = 0.003) and bile leak/biloma (12.3% vs. 5.3%, p = 0.028). On subgroup analysis, in patients with grade III injury, the incidence of liver necrosis/abscess and bile leak/biloma remained significantly higher after GSW (13.9% vs. 3.1%, p = 0.008 and 11.1% vs. 2.5%, p = 0.018, respectively). In sub analysis of 88 patients with leading severe liver injuries, GSW had a significantly longer hospital length of stay, ICU length of stay, and ventilator days.

CONCLUSION

GSW mechanism to the liver is associated with a higher incidence of liver-related complications than blunt force injury.

Plasma ammonia levels predict hospitalisation with liver-related complications and mortality in clinically stable outpatients with cirrhosis

BACKGROUND & AIMS

Hyperammonaemia is central in the pathogenesis of hepatic encephalopathy. It also has pleiotropic deleterious effects on several organ systems, such as immune function, sarcopenia, energy metabolism and portal hypertension. This study was performed to test the hypothesis that severity of hyperammonaemia is a risk factor for liver-related complications in clinically stable outpatients with cirrhosis.

METHODS

We studied 754 clinically stable outpatients with cirrhosis from 3 independent liver units. Baseline ammonia levels were corrected to the upper limit of normal (AMM-ULN) for the reference laboratory. The primary endpoint was hospitalisation with liver-related complications (a composite endpoint of bacterial infection, variceal bleeding, overt hepatic encephalopathy, or new onset or worsening of ascites). Multivariable competing risk frailty analyses using fast unified random forests were performed to predict complications and mortality. External validation was carried out using prospective data from 130 patients with cirrhosis in an independent tertiary liver centre.

RESULTS

Overall, 260 (35%) patients were hospitalised with liver-related complications. On multivariable analysis, AMM-ULN was an independent predictor of both liver-related complications (hazard ratio 2.13; 95% CI 1.89-2.40; p <0.001) and mortality (hazard ratio 1.45; 95% CI 1.20-1.76; p <0.001). The AUROC of AMM-ULN was 77.9% for 1-year liver-related complications, which is higher than traditional severity scores. Statistical differences in survival were found between high and low levels of AMM-ULN both for complications and mortality (p <0.001) using 1.4 as the optimal cut-off from the training set. AMM-ULN remained a key variable for the prediction of complications within the random forests model in the derivation cohort and upon external validation.

CONCLUSION

Ammonia is an independent predictor of hospitalisation with liver-related complications and mortality in clinically stable outpatients with cirrhosis and performs better than traditional prognostic scores in predicting complications.

LAY SUMMARY

We conducted a prospective cohort study evaluating the association of blood ammonia levels with the risk of adverse outcomes in 754 patients with stable cirrhosis across 3 independent liver units. We found that ammonia is a key determinant that helps to predict which patients will be hospitalised, develop liver-related complications and die; this was confirmed in an independent cohort of patients.

Established and emerging factors affecting the progression of nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) has become the most common chronic liver disease affecting approximately 25% of the global population. Although a majority of NAFLD patients will never experience liver-related symptoms it is estimated that 5-10% will develop cirrhosis-related complications with risk of death or need for liver transplantation. NAFLD is closely associated with cardiovascular disease and components of the metabolic syndrome. However, NAFLD is not uncommon in lean individuals and may in these subjects represent a different entity with separate pathophysiological mechanisms involved implying a higher risk for development of end-stage liver disease. There is considerable fluctuation in the histopathological course of NAFLD that may partly be attributed to lifestyle factors and dietary composition. Nutrients such as fructose, monounsaturated fatty acids, and trans-fatty acids may aggravate NAFLD. Presence of type 2 diabetes mellitus seems to be the most important clinical predictor of liver-related morbidity and mortality in NAFLD. Apart from severity of the metabolic syndrome, genetic polymorphisms and environmental factors, such as moderate alcohol consumption, may explain the variation in histopathological and clinical outcome among NAFLD patients.

Major hepatectomy for intrahepatic cholangiocarcinoma or colorectal liver metastases. Are we talking about the same story?

INTRODUCTION

Major hepatectomy (MH) is often needed in the curative management of intrahepatic cholangiocarcinoma (IHCC) and colorectal liver metastases (CRLM). While similar outcomes could be expected after MH for IHCC and CRLM, outcomes seem worse after MH for IHCC. A better understanding of such differences might help improving perioperative outcomes but comprehensive analysis are lacking.

METHODS

All patients undergoing curative intent MH for IHCC or CRLM from 2003 to 2009 were included from two dedicated multi-institutional datasets. Preoperative management and short-term outcomes after MH were first compared. Independent predictors of postoperative mortality and morbidity were identified.

RESULTS

Among 827 patients, 333 and 494 patients underwent MH for IHCC and CRLM, respectively. Preoperative portal vein embolization was more frequently performed in the CRLM group (p < 0.001). MH in the IHCC group required more extended resection (p < 0.001). Postoperative mortality and severe morbidity rates were significantly higher in the IHCC group (7.2% vs. 1.2% and 29.7% vs. 11.1%, p < 0.001, respectively). Main causes for mortality were postoperative liver failure and deep surgical site infection. MH for IHCC was an independent risk factor for mortality (p < 0.001) and severe morbidity (p < 0.001). After propensity score matching (212 patients in each group), the aforementioned differences regarding outcomes remained statistically significant.

CONCLUSION

This study suggests that IHCC patients are inherently more at risk after MH as compared to CRLM patients. Considering that postoperative liver failure was the most frequent cause of death, preoperative planning might have been inadequate in the setting of IHCC while more complex/extended resections should be expected.

Fibrosis Regression Explains Differences in Outcome in HIV-/HCV-Coinfected Patients with Cirrhosis After Sustained Virological Response

BACKGROUND AND AIMS

Fibrosis regression (FR) after sustained virological response (SVR) should produce a better outcome in hepatitis C (HCV)-/HIV-coinfected patients with liver cirrhosis, but there are no specific data in this issue.

METHODS

We compared the incidence rate (IR) and the time to develop a liver complication and death in 133 cirrhotic patients according to SVR or/and FR.

RESULTS

Of 42 patients with SVR, 23 (55%) had FR, in comparison with only 14 of the 91 (15%) without SVR. During a follow-up of 6.8 years (916.8 person-years), the IR of death, liver-related death, and liver-related complications were 2.45, 0.61, and 1.22 per 100 persons/year among SVR/FR, and 7.6, 5.9, and 6.81 among non-SVR without FR (p < 0.01), respectively. SVR patients without FR had also a lower rate of liver-related complications (1.78 vs 3.25; p = 0.02), but a worse IR of death (5.36) and liver-related death (2.68) than non-SVR patients with FR (1.3, and 0.65; p < 0.01). Moreover, FR was associated with less hospital admissions and decreasing alpha-fetoprotein levels. In Cox analysis, only FR was associated with a lower risk of death (adjusted hazard ratio, HR 0.36; 95% CI 0.15-0.86), and liver-related death (HR 0.15; 95% CI 0.03-0.65), whereas both FR (HR 0.09; 95% CI 0.03-0.3, p < 0.01) and SVR (HR 0.24; 95% CI 0.07-0.87) decreased the risk of liver-related complications.

CONCLUSION

Fibrosis regression after SVR is associated with the highest reduction in death of any cause, liver-related mortality, and liver-related complications in HIV-/HCV-coinfected patients with cirrhosis.