Análisis del sistema de alistamiento y priorización para trasplante hepático de adultos en Chile

Background: In Chile, organ allocation for liver transplantation (LT) in adults is prioritized according to the MELD-Na score. Exceptions such as Hepatocellular Carcinoma (HCC) and other non-HCC exceptions receive a score called Operational MELD score. Aim: To evaluate the effectiveness of the MELD-Na score and the operational MELD score as a prioritization system for LT in Chile. Material and Methods: Retrospective analysis of the waiting list (WL) of adult candidates (≥ 15 years) for elective LT in Chile from 2011 to 2017. The probability of leaving the WL, defined by death or contraindication for LT was compared in three groups: 1) Cirrhotic patients prioritized according to their real MELD-Na score (CPM), 2) HCC and 3) other non-HCC exceptions. Results: We analyzed 730 candidates for LT, with a median age of 57 years, 431 (56%) were men. In the study period, 352 LT were performed (48%). The annual exit rate was significantly higher in the CPM group (45.5%) compared to HCC (33.1%) and non-HCC (29.3%), (p < 0.001). Post LT survival was 86% at 1 year and 85% at 5 years, without significant differences between groups. In the CPM group, post-transplant survival was significantly lower (p < 0.05) in patients with MELD-Na ≥ 30 at transplant (81% per year) compared to patients with patients with MELD-Na < 30 (91% per year). Conclusions: MELD-Na score can discriminate very well patients who have a higher risk of death in the short and medium term. However, the assignment of operational scores for situations of exception produces inequities in the allocation of organs for LT and must therefore be carefully adjusted.

An international multicenter study of protocols for liver transplantation during a pandemic: A case for quadripartite equipoise.

BACKGROUND & AIMS: The outbreak of COVID-19 has vastly increased the operational burden on healthcare systems worldwide. For patients with end-stage liver failure, liver transplantation is the only option. However, the strain on intensive care facilities caused by the pandemic is a major concern. There is an urgent need for ethical frameworks to balance the need for liver transplantation against the availability of national resources. METHODS: We performed an international multicenter study of transplant centers to understand the evolution of policies for transplant prioritization in response to the pandemic in March 2020. To describe the ethical tension arising in this setting, we propose a novel ethical framework, the quadripartite equipoise (QE) score, that is applicable to liver transplantation in the context of limited national resources. RESULTS: Seventeen large- and medium-sized liver transplant centers from 12 countries across 4 continents participated. Ten centers opted to limit transplant activity in response to the pandemic, favoring a "sickest-first" approach. Conversely, some larger centers opted to continue routine transplant activity in order to balance waiting list mortality. To model these and other ethical tensions, we computed a QE score using 4 factors - recipient outcome, donor/graft safety, waiting list mortality and healthcare resources - for 7 countries. The fluctuation of the QE score over time accurately reflects the dynamic changes in the ethical tensions surrounding transplant activity in a pandemic. CONCLUSIONS: This four-dimensional model of quadripartite equipoise addresses the ethical tensions in the current pandemic. It serves as a universally applicable framework to guide regulation of transplant activity in response to the increasing burden on healthcare systems. LAY SUMMARY: There is an urgent need for ethical frameworks to balance the need for liver transplantation against the availability of national resources during the COVID-19 pandemic. We describe a four-dimensional model of quadripartite equipoise that models these ethical tensions and can guide the regulation of transplant activity in response to the increasing burden on healthcare systems.

[Analysis of the organ allocation system for liver transplantation in Chile]. / Análisis del sistema de alistamiento y priorización para trasplante hepático de adultos en Chile.

BACKGROUND: In Chile, organ allocation for liver transplantation (LT) in adults is prioritized according to the MELD-Na score. Exceptions such as Hepatocellular Carcinoma (HCC) and other non-HCC exceptions receive a score called Operational MELD score. AIM: To evaluate the effectiveness of the MELD-Na score and the operational MELD score as a prioritization system for LT in Chile. MATERIAL AND METHODS: Retrospective analysis of the waiting list (WL) of adult candidates (≥ 15 years) for elective LT in Chile from 2011 to 2017. The probability of leaving the WL, defined by death or contraindication for LT was compared in three groups: 1) Cirrhotic patients prioritized according to their real MELD-Na score (CPM), 2) HCC and 3) other non-HCC exceptions. RESULTS: We analyzed 730 candidates for LT, with a median age of 57 years, 431 (56%) were men. In the study period, 352 LT were performed (48%). The annual exit rate was significantly higher in the CPM group (45.5%) compared to HCC (33.1%) and non-HCC (29.3%), (p < 0.001). Post LT survival was 86% at 1 year and 85% at 5 years, without significant differences between groups. In the CPM group, post-transplant survival was significantly lower (p < 0.05) in patients with MELD-Na ≥ 30 at transplant (81% per year) compared to patients with patients with MELD-Na < 30 (91% per year). CONCLUSIONS: MELD-Na score can discriminate very well patients who have a higher risk of death in the short and medium term. However, the assignment of operational scores for situations of exception produces inequities in the allocation of organs for LT and must therefore be carefully adjusted.

The impact of transarterial chemoembolization induced complications on outcomes after liver transplantation: A propensity-matched study.

BACKGROUND: Loco-regional complications of transarterial chemoembolization (TACE) may adversely affect technical aspects of the liver transplantation (LT). This study reviewed the impact of those complications on postoperative outcomes encompassing implications on graft selection. METHODS: A retrospective, propensity score matching (1:1) analysis accounting for donor and recipient confounders was performed on a dataset of patients undergoing LT for hepatocellular carcinoma. Outcomes of patients who had TACE (TACE-group) were compared with those who did not (NoTACE-group). RESULTS: A total of 57 matched pairs were analyzed. TACE achieved effective tumor control (Pre-TACE vs Post-TACE; Median: 44 mm [interquartile range: 43-50] vs 17 mm [0-36]; P = .002) on imaging follow-up. TACE group had, at the hepatectomy, higher incidence of ischemia-related complications (adhesions of the necrotic tumor, cholecystitis, and/or bile duct necrosis) (40.4% vs 10.5%; P = .001). Overall major post-LT complications rate (Dindo-Clavien ≥3) were similar (P = .134). Those in the TACE group with donors after circulatory death (DCD) had 4.6% 90-day mortality and 54.3% major complication rate compared to 6.9% and 77.3% (P = .380 and P = .112, respectively). CONCLUSION: TACE was an effective bridging procedure that may complicate LT inducing ischemic-related complications; nevertheless, it has not shown repercussions on mortality or morbidity after the procedure, even using donors after circulatory death.

Percutaneous transhepatic cholangiographic endobiliary forceps biopsy versus endoscopic ultrasound fine needle aspiration for proximal biliary strictures: a single-centre experience.

BACKGROUND: Endoscopic ultrasound fine needle aspiration (EUS-FNA) and percutaneous transhepatic cholangiographic endobiliary forceps biopsy (PTC-EFB) are valid procedures for histological assessment of proximal biliary strictures (PBS), but their performances have never been compared. This study aimed to compare the diagnostic performance of these two techniques. METHOD: The diagnostic performances of EUS-FNA and PTC-EFB were compared in a retrospective cohort of patients assessed for PBS from 2011 to 2015 at a single tertiary centre. An inverse probability of treatment weighting (IPTW) was performed to adjust for covariate imbalance. RESULTS: A total of 102 EUS-FNAs and 75 PTC-EFBs (performed in 137 patients) were compared. Patients in the PTC-EFB group had higher preoperative bilirubin (243 versus 169 µmol/l, p = 0.005) and a higher incidence of malignancy (87% versus 67%, p = 0.008). Both techniques showed specificity and positive predictive value of 100%, and similar sensitivity (69% versus 75%, p = 0.45), negative predictive value (58% versus 38%, p = 0.15) and accuracy (78% versus 79%, p = 1.00). After IPTW, the diagnostic performance of the two techniques remained similar. CONCLUSION: Compared to EUS-FNA, PTC-EFB provides similar sensitivity, negative predictive value and accuracy. It should therefore be considered as the preferred tissue-sampling procedure, if biliary drainage is indicated.

Preoperative Thromboelastography as a Sensitive Tool Predicting Those at Risk of Developing Early Hepatic Artery Thrombosis After Adult Liver Transplantation.

BACKGROUND: Whilst causes of hepatic artery thrombosis (HAT) after liver transplantation (LT) are multifactorial, early HAT (E-HAT) remains pertinent complication impacting on graft and patient survival. Currently there is no screening tool that would identify patients with increased risk of developing E-HAT. METHODS: We analyzed the native procoagulant state of LT recipients, identified through pretransplant thromboelastographic (TEG) data among other known risk factors, to identify risk factors for E-HAT. RESULTS: The outcomes of 828 adult patients undergoing LT between 2008 and 2013 were analyzed. Overall, 79 (9.5%) patients experienced HAT, E-HAT was diagnosed in 23, and in the remainder this was "late" HAT. The maximum amplitude (MA) on preoperative TEG was significantly higher in patients diagnosed with E-HAT compared with those who did not (71.2 mm vs 57.9 mm; P < 0.0001). Receiver operating characteristic analysis with the cutoff value for MA of 65 mm or greater returned area under the curve of 0.750 (P < 0.001) predicting E-HAT with a sensitivity of 70%. A total of 7% of patients with an MA of 65 mm or greater went on to develop E-HAT (hazard ratio, 5.28; 95% confidence interval, 2.10-12.29; P < 0.001), whereas only 1.2% patients with an MA less than 65 mm experienced E-HAT. CONCLUSIONS: Preoperative TEG may reliably identify group of recipients at greater risk of developing E-HAT, and intense surveillance and anticoagulation prophylaxis may avoid this serious complication after LT.