Advantages and Limitations of Clinical Scores for Donation After Circulatory Death Liver Transplantation

Background: Scoring systems have been proposed to select donation after circulatory death (DCD) donors and recipients for liver transplantation (LT). We hypothesized that complex scoring systems derived in large datasets might not predict outcomes locally.Methods: Based on 1-year DCD-LT graft survival predictors in multivariate logistic regression models, we designed, validated, and compared a simple index using the University of California, San Francisco (UCSF) cohort (n = 136) and a universal-comprehensive (UC)-DCD score using the United Network for Organ Sharing (UNOS) cohort (n = 5,792) to previously published DCD scoring systems.Results: The total warm ischemia time (WIT)-index included donor WIT (dWIT) and hepatectomy time (dHep). The UC-DCD score included dWIT, dHep, recipient on mechanical ventilation, transjugular-intrahepatic-portosystemic-shunt, cause of liver disease, model for end-stage liver disease, body mass index, donor/recipient age, and cold ischemia time. In the UNOS cohort, the UC-score outperformed all previously published scores in predicting DCD-LT graft survival (AUC: 0.635 vs. ≤0.562). In the UCSF cohort, the total WIT index successfully stratified survival and biliary complications, whereas other scores did not.Conclusion: DCD risk scores generated in large cohorts provide general guidance for safe recipient/donor selection, but they must be tailored based on non-/partially-modifiable local circumstances to expand DCD utilization.

Predictors of Delayed Graft Function in Renal Transplantation

<b><i>Purpose:</i></b> This study aimed to analyze our data on delayed graft function (DGF) and to identify associated factors. <b><i>Methods:</i></b> This is a retrospective case-control study of all patients transplanted in our center over a period of 11 years (January 1, 2003, to December 31, 2014) comparing patients with immediate graft function (<i>n</i> = 332) to those with DGF (<i>n</i> = 165). DGF was defined as the need for hemodialysis within the first 7 days after transplantation. Donor and recipient characteristics as well as procedural factors were compared by univariate and multivariate logistic regression analyses. <b><i>Results:</i></b> Overall, 33% of patients had DGF. The rate of DGF declined from 2003 to 2011. In cases with DGF, donors and recipients were significantly older (<i>p</i> = 0.004 and <i>p</i> = 0.005, respectively), had longer cold ischemia times (<i>p</i> = 0.039), more revision surgeries (<i>p</i> &#x3c; 0.001), and more HLA mismatches (<i>p</i> = 0.001), especially in the DR locus (<i>p</i> = 0.002). Neither donor nor recipient gender, waiting time, nor CMV status had any influence. In multivariable analysis, significant risk factors were ischemia time and mismatches at the HLA-DR loci. <b><i>Conclusions:</i></b> DGF is a common complication in renal transplantation which occurred in 33% of our cases. Important factors identified were donor and recipient age, ischemia time, HLA mismatching, and revision surgery.

Increase of Myocardial Ischemia Time and Short-Term Prognosis of Patients with Acute Myocardial Infarction during the First COVID-19 Pandemic Wave

Background and objectives: early reports showed a decrease in admission rates and an increase in mortality of patients with acute myocardial infarction (AMI) during the first wave of COVID-19 pandemic. We sought to investigate whether the COVID-19 pandemic and associated lockdown had an impact on the ischemia time and prognosis of patients suffering from AMI in the settings of low COVID-19 burden. Materials and Methods: we conducted a retrospective data analysis from a tertiary center in Lithuania of 818 patients with AMI. Data were collected from 1 March to 30 June in 2020 during the peri-lockdown period (2020 group; n = 278) and compared to the same period last year (2019 group; n = 326). The primary study endpoint was all-cause mortality during 3 months of follow-up. Secondary endpoints were heart failure severity (Killip class) on admission and ischemia time in patients with acute ST segment elevation myocardial infarction (STEMI). Results: there was a reduction of 14.7% in admission rate for acute myocardial infarction (AMI) during the peri-lockdown period. The 3-month mortality rate did not differ significantly (6.9% in 2020 vs. 10.5% in 2019, p = 0.341 for STEMI patients; 5.3% in 2020 vs. 2.6% in 2019, p = 0.374 for patients with acute myocardial infarction without ST segment elevation (NSTEMI)). More STEMI patients presented with Killip IV class in 2019 (13.5% vs. 5.5%, p = 0.043, respectively). There was an increase of door-to-PCI time (54.0 [42.0–86.0] in 2019; 63.5 [48.3–97.5] in 2020, p = 0.018) and first medical contact (FMC)-to-PCI time (101.0 [82.5–120.8] in 2019; 115 [97.0–154.5] in 2020, p = 0.01) during the pandemic period. Conclusions: There was a 14.7% reduction of admissions for AMI during the first wave of COVID-19. FMC-to-PCI time increased during the peri-lockdown period, however, it did not translate into worse survival during follow-up.

Donor Death Category Is an Effect Modifier Between Cold Ischemia Time and Post-transplant Graft Function in Deceased-Donor Kidney Transplant Recipients

Objectives: We aimed to analyze the effect of cold ischemia time (CIT) on post-transplant graft function through mixed-effect model analysis to reduce the bias caused by paired mate kidneys.Methods: We reviewed all kidney transplantation records from 2015 to 2019 at our center. After applying the exclusion criteria, 561 cases were included for analysis. All donor characteristics, preservation and matching information, and recipient characteristics were collected. Transplant outcomes included delayed graft function (DGF) and estimated glomerular filtration rate (eGFR). Generalized linear mixed models were applied for analysis. We also explored potential effect modifiers, namely, donor death category, expanded criteria donors, and donor death causes.Results: Among the 561 cases, 79 DGF recipients developed DGF, and 15 recipients who died after surgery were excluded from the eGFR estimation. The median stable eGFR of the 546 recipients was 60.39 (47.63, 76.97) ml/min/1.73 m2. After adjusting for confounding covariates, CIT had a negative impact on DGF incidence [odds ratio = 1.149 (1.006, 1.313), P = 0.041]. In the evaluation of the impact on eGFR, the regression showed that CIT had no significant correlation with eGFR [β = −0.287 (−0.625, 0.051), P = 0.096]. When exploring potential effect modifiers, only the death category showed a significant interaction with CIT in the effect on eGFR (Pinteraction = 0.027). In the donation after brain death (DBD) group, CIT had no significant effect on eGFR [β = 0.135 (−0.433, 0.702), P = 0.642]. In the donation after circulatory death/donation after brain death followed by circulatory death (DCD/DBCD) group, CIT had a significantly negative effect on eGFR [β= −0.700 (−1.196, −0.204), P = 0.006]. Compared to a CIT of 0–6 h, a CIT of 6–8 or 8–12 h did not decrease the post-transplant eGFR. CIT over 12 h (12–16 h or over 16 h) significantly decreased eGFR. With the increase in CIT, the regenerated eGFR worsened (Ptrend = 0.011).Conclusion: Considering the effect of paired mate kidneys, the risk of DGF increased with prolonged CIT. The donor death category was an effect modifier between CIT and eGFR. Prolonged CIT did not reduce the eGFR level in recipients from DBDs but significantly decreased the eGFR in recipients from DCDs/DBCDs. This result indicates the potential biological interaction between CIT and donor death category.

Factors Influencing Warm Ischemia Time in Robot-assisted Partial Nephrectomy Change Depending on the Surgeon’s Experience

INTRODUCTION: Warm ischemia time (WIT) is a primary concern for robot-assisted laparoscopic partial nephrectomy (RALPN) patients because longer WIT is significantly associated with postoperative deteriorating kidney function. Tumor complexity, determined by the RENAL nephrometry score (RENAL score), can help predict surgical outcomes, but it is unclear what RENAL score and clinical factors affect WIT. This study explored the clinical factors predicting long WIT in RALPN.MATERIALS AND METHODS: In our institute, 174 RALPNs were performed between November 2013 and February 2021, of which 114 were performed by a single surgeon and included in this study. Clinical staging and the total RENAL score were determined based on preoperative CT scans. The cases were divided into three groups based on experience: period 1: 1–38, period 2: 39–76, and period 3: 77–114. The clinical factors associated with longer WIT were analyzed per period. RESULTS: The overall median tumor diameter was 32 mm, and one patient had a positive surgical margin, but there were no cancer-related deaths. In total, there were 18 complications (15.8 %). Periods 2 and 3 had larger tumor diameters (p<0.01) and worse preoperative kidney function (p=0.029) than period 1. A RENAL L-component score of 3 was associated with longer WIT in period 3 (odds ratio: 3.900; 95 % confidence interval: 1.004–15.276; p = 0.044), but the tumor diameter and the total RENAL score were not.CONCLUSIONS: A large tumor in the central lesion indicated by the RENAL L-component score was associated with increased WIT in RALPN.

Outcome of simultaneous angioembolization and nephron sparing surgery in large renal angiomyolipomas

Aim: To study the outcome of simultaneous angioembolization and nephron sparing surgery in large renal angiomyolipomas. Materials and methods: A prospective study of carried out from 2016 to 2019. A total of 15 patients were included in the study with a lesion (angiomyolipoma) more than 10 cm in size, suitable for nephron sparing surgery. The workup of the patients included history, baseline blood investigations, ultrasonography, and CT urography including angiographic films. All the patients were taken up for selective of angioembolization of the feeding vessels of the AML carried out by the interventional radiologist followed by nephron sparing surgery in the same sitting. The short term outcomes studied were warm ischemia time, average blood loss, and length of post-operative hospital stay. The oncological outcome was evaluated by noting the surgical margins of histopathological specimen and functional outcome by assessing the function of the preserved renal parenchyma. Results: Twelve out of fifteen cases were female. The mean age was 42.25 years. All the patients had lesion more than 10 cm with seven tumors located at the lower pole, four at mid-pole, and four at upper pole. Eight patients had low complexity score on RENAL score (i.e. 4–6), five patients medium complexity score (i.e. 7–9), and two had high complexity score (i.e. ⩾10). Average blood loss was 200 ml, warm ischemia time was 18.46 min and postoperative stay was 3.55 days. All the 15 specimens sent for histopathology were confirmed as AML (angiomyolipomas) with margins free of tumor. Follow up CECT done at 4 months postoperatively revealed functioning residual renal parenchyma with prompt excretion of contrast. Conclusion: Large AML’s are also amenable to nephron sparing surgery. However patient should always be warned about the possibility of total nephrectomy. Selective angioembolization helps in reducing the blood supply and risk of torrential bleeding thus facilitates in the removal of the tumor and increasing the chances of nephron sparing surgery.

Rapid postmortem ventilation improves donor lung viability by extending the tolerable warm ischemic time after cardiac death in mice

Uncontrolled donation after cardiac death (uDCD) contributes little to ameliorating donor lung shortage due to rapidly progressive warm ischemia after circulatory arrest. Here, we demonstrated non-hypoxia improves donor lung viability in a novel uDCD lung transplant model undergoing rapid ventilation after cardiac death and compared the evolution of ischemia-reperfusion injury in mice that underwent pulmonary artery ligation (PAL). The tolerable warm ischemia time at 37ºC was initially determined in mice using a modified PAL model. The donor lung following PAL was also transplanted into syngeneic mice and compared to those that underwent rapid ventilation or no ventilation at 37ºC prior to transplantation. Twenty-four hours following reperfusion, lung histology, PaO2/FIO2 ratio, and inflammatory mediators were measured. Four hours of PAL had little impact on PaO2/FIO2 ratio and acute lung injury score in contrast to significant injury induced by 5 hours of PAL. Four-hour PAL lungs showed an early myeloid-dominant inflammatory signature when compared to naïve lungs and substantially injured five-hour PAL lungs. In the context of transplantation, unventilated donor lungs showed severe injury after reperfusion, whereas ventilated donor lungs showed minimal changes in PaO2/FIO2 ratio, histologic score, and expression of inflammatory markers. Taken together, the tolerable warm ischemia time of murine lungs at 37oC can be extended by maintaining alveolar ventilation for up to 4 hours. Non-hypoxic lung warm ischemia-reperfusion injury shows an early transcriptional signature of myeloid cell recruitment and extracellular matrix proteolysis prior to blood-gas barrier dysfunction and significant tissue damage.