Analysis of predictors of adherent perinephric fat and its impact on perioperative outcomes in laparoscopic partial nephrectomy: a retrospective case–control study

Background Adherent perinephric fat (APF), characterized by inflammatory fat surrounding the kidney, can limit the isolation of renal tumors and increase the operative difficulty in laparoscopic partial nephrectomy (LPN). The aim of this study was to investigate the predictors of APF and its impact on perioperative outcomes during LPN. Methods A total of 215 consecutive patients undergoing LPN for renal cell carcinoma (RCC) from January 2017 to June 2019 at our institute were included. We divided these patients into two groups according to the presence of APF. Radiographic data were retrospectively collected from preoperative cross-sectional imaging. The perioperative clinical parameters were compared between the two groups. Univariate and multivariate analyses were performed to evaluate the predictive factors of APF. Results APF was identified in 41 patients (19.1%) at the time of LPN. Univariate analysis demonstrated that APF was significantly correlated with the male gender (P = 0.001), higher body mass index (P = 0.002), lower preoperative estimated glomerular filtration rate (P = 0.004), greater posterior perinephric fat thickness (P< 0.001), greater perinephric stranding (P< 0.001), and higher Mayo Adhesive Probability (MAP) score (P< 0.001). The MAP score (P< 0.001) was the only variable that remained an independent predictor for APF in multivariate analysis. We found that patients with APF had longer operative times (P< 0.001), warm ischemia times (P = 0.001), and greater estimated blood loss (P = 0.003) than those without APF. However, there were no significant differences in surgical approach, transfusion rate, length of postoperative stay, complication rate, or surgical margin between the two groups. Conclusions Several specific clinical and radiographic factors including the MAP score can predict APF. The presence of APF is associated with an increased operative time, warm ischemia time, and greater estimated blood loss but has no impact on other perioperative outcomes in LPN.

Comparison of Sutureless Versus Suture Partial Nephrectomy for Clinical T1 Renal Cell Carcinoma: A Meta-Analysis of Retrospective Studies

BackgroundPartial nephrectomy (PN) is the recommended treatment for T1 renal cell carcinoma (RCC). Compared with suture PN, sutureless PN reduces the difficulty and time of operation, but the safety and feasibility have been controversial. This meta-analysis was conducted to compare the function and perioperative outcomes of suture and sutureless PN for T1 RCC.MethodsSystematic literature review was performed up to April 2021 using multiple databases to identify eligible comparative studies. According to the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) criteria, identification and selection of the studies were conducted. Meta-analysis was performed for studies comparing suture to sutureless PN for both T1a and T1b RCC. In addition, subgroup analysis was performed on operation time, warm ischemia time, estimated blood loss, and postoperative complications. Sensitivity analysis was used in analysis with high heterogeneity (operation time and estimated blood loss).ResultsEight retrospective studies were included with a total of 1,156 patients; of the 1,156 patients, 499 received sutureless PN and 707 received suture PN. The results showed that sutureless PN had shorter operative time (I2 = 0%, P &lt; 0.001), warm ischemia time (I2 = 97.5%, P &lt; 0.001), and lower clamping rate (I2 = 85.8%, P = 0.003), but estimated blood loss (I2 = 76.6%, P = 0.064) had no difference. In the comparison of perioperative outcomes, there was no significant difference in postoperative complications (I2 = 0%, P = 0.999), positive surgical margins (I2 = 0%, P = 0.356), postoperative estimated glomerular filtration rat (eGFR) (I2 = 0%, P = 0.656), and tumor recurrence (I2 = 0%, P = 0.531).ConclusionsIn T1a RCC with low RENAL score, sutureless PN is a feasible choice, whereas it should not be overestimated in T1b RCC.

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.

Normothermic ex vivo Heart Perfusion Combined With Melatonin Enhances Myocardial Protection in Rat Donation After Circulatory Death Hearts via Inhibiting NLRP3 Inflammasome-Mediated Pyroptosis

ObjectiveThe adoption of hearts from donation after circulatory death (DCD) is a promising approach for the shortage of suitable organs in heart transplantation. However, DCD hearts suffer from serious ischemia/reperfusion injury (IRI). Recent studies demonstrate that nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome-mediated pyroptosis is a novel target to ameliorate myocardial IRI. Melatonin is shown to inhibit NLRP3 inflammasome-mediated pyroptosis. Therefore, this study is designed to verify the hypothesis that melatonin can protect the heart graft preserved with ex vivo heart perfusion (EVHP) against myocardial IRI via inhibiting NLRP3 inflammasome-mediated pyroptosis in a rat model of DCD.MethodsDonor-heart rats were randomly divided into three groups: (1) Control group: non-DCD hearts were harvested from heart-beating rats and immediately preserved with allogenic blood-based perfusate at constant flow for 105 min in the normothermic EVHP system; (2) DCD-vehicle group; and (3) DCD-melatonin group: rats were subjected to the DCD procedure with 25 min of warm ischemia injury and preserved by the normothermic EVHP system for 105 min. Melatonin (200 μmol/L) or vehicle was perfused in the cardioplegia and throughout the whole EVHP period. Cardiac functional assessment was performed every 30 min during EVHP. The level of oxidative stress, inflammatory response, apoptosis, and NLRP3 inflammasome-mediated pyroptosis of heart grafts submitted to EVHP were evaluated.ResultsTwenty five-minute warm ischemia injury resulted in a significant decrease in the developed pressure (DP), dP/dtmax, and dP/dtmin of left ventricular of the DCD hearts, while the treatment with melatonin significantly increased the DP, dP/dtmax of the left ventricular of DCD hearts compared with DCD-vehicle group. Furthermore, warm ischemia injury led to a significant increase in the level of oxidative stress, inflammatory response, apoptosis, and NLRP3 inflammasome-mediated pyroptosis in the hearts preserved with EVHP. However, melatonin added in the cardioplegia and throughout the EVHP period significantly attenuated the level of oxidative stress, inflammatory response, apoptosis, and NLRP3 inflammasome-mediated pyroptosis compared with DCD-vehicle group.ConclusionEVHP combined with melatonin post-conditioning attenuates myocardial IRI in DCD hearts by inhibiting NLRP3 inflammasome-mediated pyroptosis, which might expand the donor pool by the adoption of transplantable DCD hearts.

The Effects of 6-Chromanol SUL-138 during Hypothermic Machine Perfusion on Porcine Deceased Donor Kidneys

Diminishing ischemia-reperfusion injury (IRI) by improving kidney preservation techniques offers great beneficial value for kidney transplant recipients. Mitochondria play an important role in the pathogenesis of IRI and are therefore interesting targets for pharmacological interventions. Hypothermic machine perfusion (HMP), as a preservation strategy, offers the possibility to provide mitochondrial–targeted therapies. This study focuses on the addition of a mitochondrial protective agent SUL—138 during HMP and assesses its effect on kidney function and injury during normothermic reperfusion. In this case, 30 min of warm ischemia was applied to porcine slaughterhouse kidneys before 24 h of non–oxygenated HMP with or without the addition of SUL—138. Functional assessment was performed by 4 h normothermic autologous blood reperfusion. No differences in renal function or perfusion parameters were found between both groups. ATP levels were lower after 30 min of warm ischemia in the SUL–138 group (n.s, p = 0.067) but restored significantly during 24 h of HMP in combination with SUL—138. Aspartate aminotransferase (ASAT) levels were significantly lower for the SUL—138 group. SUL—138 does not influence renal function in this model. Restoration of ATP levels during 24 h of HMP with the addition of SUL in combination with lower ASAT levels could be an indication of improved mitochondrial function.

Melatonin and Glycine Reduce Uterus Ischemia/Reperfusion Injury in a Rat Model of Warm Ischemia

Ischemia/reperfusion injury (IRI) remains a significant problem to be solved in uterus transplantation (UTx). Melatonin and glycine have been shown to possess direct cytoprotective activities, mainly due to their antioxidative and anti-inflammatory properties. The aim of this study was to investigate the protective effects of melatonin and glycine and their combination on IRI in a rat model of warm ischemia. In this study, Sprague-Dawley rats were assigned to eight groups, including sham and IRI (n = 80). Melatonin and glycine alone or their combination were administered prior to 1 h of uterus ischemia followed by 1 h of reperfusion. Melatonin (50 mg/kg) was administered via gavage 2 h before IRI and glycine in an enriched diet for 5 days prior to intervention. Uterus IRI was estimated by histology, including immunohistochemistry, and biochemical tissue analyses. Histology revealed that uterus IRI was significantly attenuated by pretreatment with melatonin (p = 0.019) and glycine (p = 0.044) alone as well as their combination (p = 0.003). Uterus IRI led to increased myeloperoxidase expression, which was significantly reduced by melatonin (p = 0.004), glycine (p < 0.001) or their combination (p < 0.001). The decline in superoxide dismutase activity was significantly reduced in the melatonin (p = 0.027), glycine (p = 0.038) and combined treatment groups (p = 0.015) when compared to the IRI control group. In conclusion, melatonin, glycine and their combination significantly reduced oxidative stress-induced cell damage after IRI in a small animal warm ischemia model, and, therefore, clinical studies are required to evaluate the protective effects of these well-characterized substances in uterus IRI.