There is a limited access to liver transplantation, however, many organs are discarded based on subjective assessment only. Here we report the VITTAL clinical trial (ClinicalTrials.gov number NCT02740608) outcomes, using normothermic machine perfusion (NMP) to objectively assess livers discarded by all UK centres meeting specific high-risk criteria. Thirtyone livers were enroled and assessed by viability criteria based on the lactate clearance to levels ≤2.5 mmol/L within 4 h. The viability was achieved by 22 (71%) organs, that were transplanted after a median preservation time of 18 h, with 100% 90-day survival. During the median follow up of 542 days, 4 (18%) patients developed biliary strictures requiring retransplantation. This trial demonstrates that viability testing with NMP is feasible and in this study enabled successful transplantation of 71% of discarded livers, with 100% 90-day patient and graft survival; it does not seem to prevent non-anastomotic biliary strictures in livers donated after circulatory death with prolonged warm ischaemia.
Background Mitochondrial succinate accumulation has been suggested as key event for ischemia reperfusion injury in mice. No specific data are however available on behavior of liver mitochondria during ex situ machine perfusion in clinical transplant models. Methods We investigated mitochondrial metabolism of isolated perfused rat livers before transplantation. Livers were exposed to warm and cold ischemia to simulate donation after circulatory death (DCD) and organ transport. Subsequently, livers were perfused with oxygenated Belzer-MPS for 1h, at hypothermic or normothermic conditions. Various experiments were performed with supplemented succinate and/or mitochondrial inhibitors. The perfusate, liver tissues, and isolated mitochondria were analyzed by mass-spectroscopy and fluorimetry. Additionally, rat DCD livers were transplanted after 1h hypothermic or normothermic oxygenated perfusion. In parallel, perfusate samples were analysed during HOPE-treatment of human DCD livers before transplantation. Findings Succinate exposure during rat liver perfusion triggered a dose-dependent release of mitochondrial Flavin-Mononucleotide (FMN) and NADH in perfusates under normothermic conditions. In contrast, perfusate FMN was 3-8 fold lower under hypothermic conditions, suggesting less mitochondrial injury during cold re-oxygenation compared to normothermic conditions. HOPE-treatment induced a mitochondrial reprogramming with uploading of the nucleotide pool and effective succinate metabolism. This resulted in a clear superiority after liver transplantation compared to normothermic perfusion. Finally, the degree of mitochondrial injury during HOPE of human DCD livers, quantified by perfusate FMN and NADH, was predictive for liver function. Interpretation Mitochondrial injury determines outcome of transplanted rodent and human livers. Hypothermic oxygenated perfusion improves mitochondrial function, and allows viability assessment of liver grafts before implantation. Funding detailed information can be found in Acknowledgments.
It has been proposed that several neurohumoral factors may be involved in the genesis of vascular structural changes (remodeling or hypertrophy) frequently observed in essential hypertension. Therefore, in this study we investigated vascular structural alterations of subcutaneous small resistance arteries in patients with secondary forms of hypertension. The study included 70 participants: 11 with pheochromocytoma, 13 with primary aldosteronism, and 17 with renovascular hypertension; 13 normotensive subjects and 16 patients with essential hypertension served as controls. All subjects were submitted to a biopsy of subcutaneous fat. Small resistance arteries were dissected and mounted on a micromyograph, and media-lumen ratio, media thickness, remodeling index, and growth index were evaluated. Endothelial function was evaluated according to the dose-response curve to acetylcholine. In patients with either primary aldosteronism or renovascular hypertension, a marked increase in media-lumen ratio was observed, whereas in patients with pheochromocytoma, the extent of vascular structural alterations was similar to that observed in patients with essential hypertension. The increase in media-lumen ratio in patients with essential hypertension and with pheochromocytoma was mainly due to vascular remodeling (remodeling index, 93% to 94%), whereas in patients with renovascular hypertension, there was vascular growth (remodeling index, 70%; growth index, 53%). Patients with primary aldosteronism had an intermediate pattern compared with the other two forms of secondary hypertension. An evident impairment of endothelial function was observed in all four hypertensive groups. In conclusion, the renin-angiotensin-aldosterone system seems to be more powerful than the adrenergic system in inducing vascular growth.
Background Surgery is the main modality of cure for solid cancers and was prioritised to continue during COVID-19 outbreaks. This study aimed to identify immediate areas for system strengthening by comparing the delivery of elective cancer surgery during the COVID-19 pandemic in periods of lockdown versus light restriction. Methods This international, prospective, cohort study enrolled 20 006 adult (≥18 years) patients from 466 hospitals in 61 countries with 15 cancer types, who had a decision for curative surgery during the COVID-19 pandemic and were followed up until the point of surgery or cessation of follow-up (Aug 31, 2020). Average national Oxford COVID-19 Stringency Index scores were calculated to define the government response to COVID-19 for each patient for the period they awaited surgery, and classified into light restrictions (index <20), moderate lockdowns (20–60), and full lockdowns (>60). The primary outcome was the non-operation rate (defined as the proportion of patients who did not undergo planned surgery). Cox proportional-hazards regression models were used to explore the associations between lockdowns and non-operation. Intervals from diagnosis to surgery were compared across COVID-19 government response index groups. This study was registered at ClinicalTrials.gov , NCT04384926 . Findings Of eligible patients awaiting surgery, 2003 (10·0%) of 20 006 did not receive surgery after a median follow-up of 23 weeks (IQR 16–30), all of whom had a COVID-19-related reason given for non-operation. Light restrictions were associated with a 0·6% non-operation rate (26 of 4521), moderate lockdowns with a 5·5% rate (201 of 3646; adjusted hazard ratio [HR] 0·81, 95% CI 0·77–0·84; p<0·0001), and full lockdowns with a 15·0% rate (1775 of 11 827; HR 0·51, 0·50–0·53; p<0·0001). In sensitivity analyses, including adjustment for SARS-CoV-2 case notification rates, moderate lockdowns (HR 0·84, 95% CI 0·80–0·88; p<0·001), and full lockdowns (0·57, 0·54–0·60; p<0·001), remained independently associated with non-operation. Surgery beyond 12 weeks from diagnosis in patients without neoadjuvant therapy increased during lockdowns (374 [9·1%] of 4521 in light restrictions, 317 [10·4%] of 3646 in moderate lockdowns, 2001 [23·8%] of 11 827 in full lockdowns), although there were no differences in resectability rates observed with longer delays. Interpretation Cancer surgery systems worldwide were fragile to lockdowns, with one in seven patients who were in regions with full lockdowns not undergoing planned surgery and experiencing longer preoperative delays. Although short-term oncological outcomes were not compromised in those selected for surgery, delays and non-operations might lead to long-term reductions in survival. During current and future periods of societal restriction, the resilience of elective surgery systems requires strengthening, which might include...
The DCD livers were allocated according to the Italian allocation policy, primarily on a regional basis. 19 Superurgent patients and candidates with a model for end-stage liver disease (MELD) score ≥30 points were excluded. Most centers preferably selected low-risk recipients and prioritized candidates, for example, with hepatocellular carcinoma (HCC).
Objective: The aim of this study was to establish clinically relevant outcome benchmark values using criteria for pancreatoduodenectomy (PD) with portomesenteric venous resection (PVR) from a low-risk cohort managed in high-volume centers. Summary Background Data: PD with PVR is regarded as the standard of care in patients with cancer involvement of the portomesenteric venous axis. There are, however, no benchmark outcome indicators for this population which hampers comparisons of patients undergoing PD with and without PVR resection. Methods: This multicenter study analyzed patients undergoing PD with any type of PVR in 23 high-volume centers from 2009 to 2018. Nineteen outcome benchmarks were established in low-risk patients, defined as the 75th percentile of the median outcome values of the centers (NCT04053998). Results: Out of 1462 patients with PD and PVR, 840 (58%) formed the benchmark cohort, with a mean age was 64 (SD11) years, 413 (49%) were females. Benchmark cutoffs, among others, were calculated as follows: Clinically relevant pancreatic fistula rate (International Study Group of Pancreatic Surgery): ≤14%; in-hospital mortality rate: ≤4%; major complication rate Grade≥3 and the CCI up to 6 months postoperatively: ≤36% and ≤26, respectively; portal vein thrombosis rate: ≤14% and 5-year survival for patients with pancreatic ductal adenocarcinoma: ≥9%. Conclusion: These novel benchmark cutoffs targeting surgical performance, morbidity, mortality, and oncological parameters show relatively inferior results in patients undergoing vascular resection because of involvement of the portomesenteric venous axis. These benchmark values however can be used to conclusively assess the results of different centers or surgeons operating on this high-risk group.
Key Points Question Can the individual risk estimation for early allograft failure (EAF) be improved in view of liver retransplant? Findings In this multicenter cohort study investigating the association between donor-recipient factors and EAF, a novel Early Allograft Failure Simplified Estimation (EASE) score was developed. The score includes Model for End-stage Liver Disease score, transfused packed red blood cells, and hepatic vessel early thrombosis as well as transaminases, platelet, and bilirubin kinetics as variables on day 10 after transplant. The EASE score outperformed previous model scores, estimating EAF risk with 87% accuracy on day 90 after transplant; EASE was developed on a multicenter Italian database (1609 recipients) and validated on an external UK database (538 recipients). Meaning In this study, the EASE score rated the EAF risk (0%-100%) and identified cases at unsustainable risk to be listed for retransplant.
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