Surgical and Functional Outcomes on Omitting Cortical Renorrhaphy During Robot-Assisted Versus Laparoscopic Partial Nephrectomy: A Match-Paired Analysis

Objectives To assess surgical and functional outcomes in comparison of cortical renorrhaphy omitting, robot-assisted partial nephrectomy (CRO-RAPN), and laparoscopic partial nephrectomy (CRO-LPN). Methods Between July 2012 and June 2020, patients with localized clinical T1-2 renal masses who underwent CRO-RAPN or CRO-LPN were reviewed. The outcomes of the CRO-RAPN and CRO-LPN groups were compared using propensity score matching. Trifecta was defined as negative surgical margin, less than 25 minutes of warm ischemic time, and no complications of Clavien-Dindo grade III or more until three months postoperatively. Preservation rate of the estimated glomerular filtration rate (eGFR) was evaluated at six months postoperatively. Results A total of 291 patients, including 210 patients who underwent CRO-RAPN and 81 patients who underwent CRO-LPN, were included, and matched pairs of 150 patients were analyzed. The CRO-RAPN group was associated with a significantly shorter warm ischemic time (13 min vs 20 min, P < 0.001), shorter total operation time (162 min vs 212 min, P < 0.001), less estimated blood loss (40 mL vs 119 mL, P = 0.002), lower incidence of overall complications (3% vs 16%, P = 0.001), higher preservation rate of eGFR at six months postoperatively (93% vs 89%, P = 0.003), and higher trifecta achievement rate (84% vs 64%, P = 0.004) than the CRO-LPN group. Conclusions CRO-RAPN contributes to a shorter warm ischemic time, less blood loss, fewer complications, and preservation of renal function and makes it feasible to achieve a higher rate of trifecta compared to CRO-LPN.

Development of a Porcine Slaughterhouse Kidney Perfusion Model

Machine perfusion techniques are becoming standard care in the clinical donation and transplantation setting. However, more research is needed to understand the mechanisms of the protective effects of machine perfusion. For preservation related experiments, porcine kidneys are acceptable alternatives to human kidneys, because of their size and similar physiology. In this experiment, the use of slaughterhouse kidneys was evaluated with normothermic kidney perfusion (NKP), thereby avoiding the use of laboratory animals. Porcine kidneys were derived from two local abattoirs. To induce different degrees of injury, different warm ischemic times and preservation techniques were used. After preservation, kidneys were reperfused for 4 h with two different NKP solutions to test renal function and damage. The effect of the preservation technique or a short warm ischemic time was clearly seen in functional markers, such as creatinine clearance and fractional sodium excretion levels, as well as in the generic damage marker lactate dehydrogenase (LDH). Porcine slaughterhouse kidneys are a useful alternative to laboratory animals for transplantation- and preservation-related research questions. To maintain kidney function during NKP, a short warm ischemic time or hypothermic machine perfusion during the preservation phase are mandatory.

RELATIONSHIP BETWEEN WARM ISCHEMIC TIME AND RESISTIVE INDEX ON CREATININ REDUCTION RATIO DAY TWO AFTER LIVING KIDNEY DONOR TRANSPLANTATION

Kidney transplantation (KT) may improve kidney function, via filtration, excretion, and hormonal function better than other kidney replacement therapies. Many factors may cause graft rejection or delayed graft function which may decrease the prognosis for graft survival. This study aims to determine associated factors of serum creatinine reduction ratio day 2 (CRR2) after living kidney donor transplants. This research used a retrospective cohort study design, with total sampling based on complete documents was done. A total 44 respondents (from 2012 to January 2020) and 22 respondents (based on the complete Resistive Index (RI) were recorded since 2018). Early Graft Function was defined using CRR2. Immediate Graft Function (IGF) was defined if CRR2 > 30% and Delayed Graft Function (DGF) if CRR2 ≤ 30%. The results of Multiple logistic regression analysis from 44 samples showed that Warm Ischemic Time (WIT) ≤ 40 minutes was significantly associated with IGF (OR 10.78; 95%CI: 1.66 to 70.16; p=0.01). A result with 22 samples showed that, only RI ≤ 0.7was significantly associated with IGF (OR 0.11; 95%CI: 0.03-0.41; p=0.002). In conclusion, WIT and RI influence on EGF with parameters CRR2 of living-donors. KT Patients with WIT ≤40 minutes and RI ≤0.7 had a higher risk of IGF.

Adult heart procurement following circulatory determined death from a donor on venous-venous extracorporeal membrane oxygenation: A case report

Donation after circulatory death in the context of heart transplants is attracting interest and becoming popular in clinical practice. Activity is growing in the United Kingdom, Australia, and the United States. We believe that a prolonged warm ischemic time (time from asystole to reperfusion of the heart on an ex vivo perfusion system) is a primary indicator of adverse outcomes. However, 1.5 liters of blood must be retrieved from the right atrium following sternotomy prolonging warm ischemic time. The patient in the following case report was supported by veno-venous extra-corporeal membrane oxygenation following drowning, further complicated by aspiration-related lung failure. Following circulatory death and a mandatory five-minute stand-off period, 1.5 liters of blood was drained from the circuit as sternotomy began. Surgeons then proceeded to direct procurement of the heart, aiming for least functional warm ischemic time. Following standard implantation, the patient’s postoperative recovery has been unremarkable to date.

Prompt Graft Cooling Enhances Cardioprotection during Heart Transplantation Procedures through the Regulation of Mitophagy

A complete and prompt cardiac arrest using a cold cardioplegic solution is routinely used in heart transplantation to protect the graft function. However, warm ischemic time is still inevitable during the procedure to isolate donor hearts in the clinical setting. Our knowledge of the mechanism changes prevented by cold storage, and how warm ischemia damages donor hearts, is extremely poor. The potential consequences of this inevitable warm ischemic time to grafts, and the underlying potential protective mechanism of prompt graft cooling, have been studied in order to explore an advanced graft protection strategy. To this end, a surgical procedure, including 10–15 min warm ischemic time during procurement, was performed in mouse models to mimic the clinical situation (Group I), and compared to a group of mice that had the procurement performed with prompt cooling procedures (Group II). The myocardial morphologic changes (including ultrastructure) were then assessed by electron and optical microscopy after 6 h of cold preservation. Furthermore, syngeneic heart transplantation was performed after 6 h of cold preservation to measure the graft heart function. An electron microscopy showed extensive damage, including hypercontracted myofibers with contraction bands, and damaged mitochondria that released mitochondrial contents in Group I mice, while similar patterns of damage were not observed in the mice from Group II. The results from both the electron microscopy and immunoblotting verified that cardiac mitophagy (protective mitochondrial autophagy) was present in the mice from Group II, but was absent in the mice from Group I. Moreover, the mice from Group II demonstrated faster rebeating times and higher beating scores, as compared to the mice from Group I. The pressure catheter system results indicated that the graft heart function was significantly more improved in the mice from Group II than in those from Group I, as demonstrated by the left ventricle systolic pressure (31.96 ± 6.54 vs. 26.12 ± 8.87 mmHg), the +dp/dt (815.6 ± 215.4 vs. 693.9 ± 153.8 mmHg/s), and the -dp/dt: (492.4 ± 92.98 vs. 418.5 ± 118.9 mmHg/s). In conclusion, the warm ischemic time during the procedure impaired the graft function and destroyed the activation of mitophagy. Thus, appropriate mitophagy activation has emerged as a promising therapeutic target that may be essential for graft protection and functional improvement during heart transplantation.

Warm ischemic time’ and renal function preservation in robotic partial nephrectomy -evaluating its real impact

Objective: To evaluate the effect of warm ischemic time (WIT) on future renal function (RF) after robotic partial nephrectomy (RPN) and secondarily, also to find out predictors of future RF after RPN. Method and materials: All patients who underwent RPN with normal pre-operative RF and normal contralateral kidney were included in the study except for those in whom one-year follow up was not completed. Patients were divided in four groups based on WIT (zero, <20minutes, 20 minutes to 30 minutes and >30 minutes). Comparison of demographic and perioperative parameters including follow-up up to one year were done. Univariable and multivariable analysis were done to detect significant correlation of RF with those parameters. Results: Total 198 RPN patients were included in the study. The four groups had comparable demographic data (age, gender, comorbidity, smoking, body mass index, pre-operative RF). Progressively increased WIT was significantly associated with increased tumour size (p=0.022), RENAL nephrometry score (p=0.003), operative time (p=0.004) and blood loss (p=0.046). Post-operatively, RF on first post-operative day (p=0.627), at one month (p=0.581) and at one year (p=0.378) had no significant difference between the four groups. Nine (4.5%) patients progressed to chronic renal disease. Pre-operative RF and perioperative complications only had significant correlation with one-year RF. Conclusion: Tumour size and RENAL nephrometry score significantly influenced WIT. Pre-operative RF and peri-operative complications were the only significant predictors of future RF and not the WIT.

Delayed graft function and perfusion parameters of kidneys from uncontrolled donors after circulatory death

Better preservation and evaluation of kidneys from donors after circulatory death serve to increase the number of kidneys available for transplantation and hypothermic machine perfusion has been shown to decrease ischemia reperfusion injury and delayed graft function. Data on relation between hemodynamic parameters during hypothermic machine perfusion and delayed graft function in kidneys from donors after circulatory death are so far scarce and not univocal. We aimed at assessing whether hemodynamic parameters measured during hypothermic machine perfusion (flow, mean perfusion pressure, and renal resistance) are associated with delayed graft function in 26 kidneys retrieved from uncontrolled donors after circulatory death. In our series, the incidence of delayed graft function was 57.7% (15/26). Recipients who developed delayed graft function had a longer warm ischemic time (p = 0.04). All hemodynamic parameters measured during hypothermic machine perfusion were comparable between recipients with delayed graft function and those without. According to our data, in kidneys from uncontrolled donors after circulatory death, a longer warm ischemic time (that is the overall time of no flow, as the sum of the no-flow and the no-touch period) is associated with delayed graft function. This finding underscores the pivotal role of ischemic injury in terms of absence of flow in affecting graft function. No association was detectable between hemodynamic parameters during hypothermic machine perfusion and the development of delayed graft function in our series.

Comparative Analysis of Risk Factors in Declined Kidneys from Donation after Brain Death and Circulatory Death

Background and objectives: Kidneys from donation after circulatory death (DCD) are more likely to be declined for transplantation compared with kidneys from donation after brain death (DBD). The aim of this study was to evaluate characteristics in the biopsies of human DCD and DBD kidneys that were declined for transplantation in order to rescue more DCD kidneys. Materials and Methods: Sixty kidney donors (DCD = 36, DBD = 24) were recruited into the study and assessed using donor demographics. Kidney biopsies taken post cold storage were also evaluated for histological damage, inflammation (myeloperoxidase, MPO), von Willebrand factor (vWF) expression, complement 4d (C4d) deposition and complement 3 (C3) activation using H&E and immunohistochemistry staining, and Western blotting. Results: More DBD donors (16/24) had a history of hypertension compared with DCDs (8/36, p = 0.001). The mean warm ischemic time in the DCD kidneys was 12.9 ± 3.9 min. The mean cold ischemic time was not significantly different between the two groups of kidney donors (DBD 33.3 ± 16.7 vs. DCD 28.6 ± 14.1 h, p > 0.05). The score of histological damage and MPO, as well as the reactivity of vWF, C4d and C3, varied between kidneys, but there was no significant difference between the two donor types (p > 0.05). However, vWF reactivity might be an early indicator for loss of tissue integrity, while C4d deposition and activated C3 might be better predictors for histological damage. Conclusions: Similar characteristics of DCD were shown in comparison with DBD kidneys. Importantly, the additional warm ischemic time in DCD appeared to have no further detectable adverse effects on tissue injury, inflammation and complement activation. vWF, C4d and C3 might be potential biomarkers facilitating the evaluation of donor kidneys.