Effect of Donor Warm Ischemia Time During Graft Extraction in Right Lobe Robotic Donor Hepatectomy on Recipient Outcomes - A Propensity Score Matched Analysis.

One of the concerns specific to minimally invasive donor hepatectomy(MIDH) is the prolonged time required for graft extraction after completion of the donor hepatectomy(donor warm ischemic time(DWIT)). There has never been an objective evaluation of MIDH-DWIT on allograft function in living donor liver transplantation(LDLT).We evaluated the effect of DWIT following robotic donor hepatectomy(RDH) on recipient outcomes and compared them with a matched cohort of open donor hepatectomy (ODH).Demographic, perioperative and recipient's post-operative outcome data for all right lobe(RL)-RDH performed between September 2019 and July 2023 was analysed and compared with a propensity-score matched cohort(1:1) of RL-ODH from the same time period. Of a total of 103 RL-RDH and 446 RL-ODH, unmatched and Propensity-score matched analysis(1:1) revealed a significantly longer DWIT in the RDH group as compared to the ODH group (9.33±3.95 Vs 2.87±2.13, p<0.0001). This did not translate into any difference in the rates of early allograft dysfunction (EAD), biliary complications(BC), major morbidity or overall 1-& 3-month survival. ROC curve analysis threshold for DWIT-EAD was 9min (AUROC:0.67,sensitivity=80%,specificity=53.8%).We show that prolonged DWIT within an acceptable range in RDH does not have deleterious effects on short-term recipient outcomes. Further long-term studies are required to confirm our findings especially with regards to non-anastomotic BC.

Cold ischemia time in liver transplantation: An overview.

The standard approach to organ preservation in liver transplantation is by static cold storage and the time between the cross-clamping of a graft in a donor and its reperfusion in the recipient is defined as cold ischemia time (CIT). This simple definition reveals a multifactorial time frame that depends on donor hepatectomy time, transit time, and recipient surgery time, and is one of the most important donor-related risk factors which may influence the graft and recipient's survival. Recently, the growing demand for the use of marginal liver grafts has prompted scientific exploration to analyze ischemia time factors and develop different organ preservation strategies. This review details the CIT definition and analyzes its different factors. It also explores the most recent strategies developed to implement each timestamp of CIT and to protect the graft from ischemic injury.

Open- vs. closed-chest pig models of donation after circulatory death.

Background: During donation after circulatory death (DCD), cardiac grafts are exposed to potentially damaging conditions that can impact their quality and post-transplantation outcomes. In a clinical DCD setting, patients have closed chests in most cases, while many experimental models have used open-chest conditions. We therefore aimed to investigate and characterize differences in open- vs. closed-chest porcine models. Methods: Withdrawal of life-sustaining therapy (WLST) was simulated in anesthetized juvenile male pigs by stopping mechanical ventilation following the administration of a neuromuscular block. Functional warm ischemic time (fWIT) was defined to start when systolic arterial pressure was <50 mmHg. Hemodynamic changes and blood chemistry were analyzed. Two experimental groups were compared: (i) an open-chest group with sternotomy prior to WLST and (ii) a closed-chest group with sternotomy after fWIT. Results: Hemodynamic changes during the progression from WLST to fWIT were initiated by a rapid decline in blood oxygen saturation and a subsequent cardiovascular hyperdynamic (HD) period characterized by temporary elevations in heart rates and arterial pressures in both groups. Subsequently, heart rate and systolic arterial pressure decreased until fWIT was reached. Pigs in the open-chest group displayed a more rapid transition to the HD phase after WLST, with peak heart rate and peak rate-pressure product occurring significantly earlier. Furthermore, the HD phase duration tended to be shorter and less intense (lower peak rate-pressure product) in the open-chest group than in the closed-chest group. Discussion: Progression from WLST to fWIT was more rapid, and the hemodynamic changes tended to be less pronounced in the open-chest group than in the closed-chest group. Our findings support clear differences between open- and closed-chest models of DCD. Therefore, recommendations for clinical DCD protocols based on findings in open-chest models must be interpreted with care.

Salvaging donated kidneys from prolonged warm ischemia during ex vivo hypothermic oxygenated perfusion.

Prolonged warm ischemic is the main cause discarding donated organs after cardiac death. Here, we identified that prolonged warm ischemic time induced disseminated intravascular coagulation and severe capillary vasospasm after cardiac death of rat kidneys. Additionally, we found a significant accumulation of fibrinogen in a hypoxic cell culture of human umbilical vein epithelial cells and in isolated kidneys exposed to prolonged warm ischemic following flushing out of blood. However, pre-flushing the kidney with snake venom plasmin in a 90-minute warm ischemic model maximized removal of micro thrombi and facilitated the delivery of oxygen and therapeutic agents. Application of carbon monoxide-releasing CORM-401 during ex vivo hypothermic oxygenated perfusion achieved multipath protective effects in prolonged warm ischemic kidneys. This led to significant improvements in perfusion parameters, restoration of the microcirculation, amelioration of mitochondrial injury, oxidative stress, and apoptosis. This benefit resulted in significantly prolonged warm ischemic kidney recipient survival rates of 70%, compared with none in those receiving ex vivo hypothermic oxygenated perfusion alone. Significantly, ex vivo hypothermic oxygenated perfusion combined with cytoprotective carbon monoxide releasing CORM-401 treatment meaningfully protected the donated kidney after cardiac death from ischemia-reperfusion injury by reducing inflammation, oxidative stress, apoptosis, and pathological damage. Thus, our study suggests a new combination treatment strategy to potentially expand the donor pool by increasing use of organs after cardiac death and salvaging prolonged warm ischemic kidneys.

Preoperative Super-Selective Embolization versus "On-Clamp" Laparoscopic Partial Nephrectomy for T1 Renal Tumors- A Prospective Randomized Study.

To analyze and compare the intraoperative and post-operative outcomes of "on-clamp" laparoscopic partial nephrectomy (LPN) with "preoperative super-selective angioembolization" before LPN. This randomized clinical study was conducted at Gauhati Medical College Hospital, Guwahati, India, between November 2021 and November 2023. Adult patients of either gender diagnosed with T1 renal tumors were included in the study. All patients underwent diethylenetriamine pentaacetate scan preoperatively and at 1-month follow-up. The patients were randomized using a parallel group design with an allocation ratio of 1:1 to receive either preoperative angioembolization followed by LPN or conventional "on-clamp" LPN. Demographic and baseline parameters were recorded along with pre- and post-operative data. There was no significant difference between the two groups in terms of age (P = 0.11), gender distribution (P = 0.32), body mass index (P = 0.43), preoperative hemoglobin (P = 0.34), and preoperative estimated glomerular filtration rate (eGFR; P = 0.64). One patient in the embolization group required radical nephrectomy because of accidental backflow of glue into the renal artery during embolization whereas four patients required clamping due to inadequate embolization. Preoperative super-selective embolization yielded significantly less blood loss, compared to "on-clamp" LPN (145 [50.76 mL] vs. 261 [66.12 mL], P < 0.01). There was no significant difference between post-operative eGFR (at 1 month) between the two groups (P = 0.71). Preoperative embolization offers improved outcomes in the dissection plane, total operative time, and blood loss, compared to conventional "on-clamp" LPN but has no significant effect on change in eGFR.

Metabolic Considerations in Direct Procurement and Perfusion Protocols with DCD Heart Transplantation.

Heart transplantation with donation after circulatory death (DCD) provides excellent patient outcomes and increases donor heart availability. However, unlike conventional grafts obtained through donation after brain death, DCD cardiac grafts are not only exposed to warm, unprotected ischemia, but also to a potentially damaging pre-ischemic phase after withdrawal of life-sustaining therapy (WLST). In this review, we aim to bring together knowledge about changes in cardiac energy metabolism and its regulation that occur in DCD donors during WLST, circulatory arrest, and following the onset of warm ischemia. Acute metabolic, hemodynamic, and biochemical changes in the DCD donor expose hearts to high circulating catecholamines, hypoxia, and warm ischemia, all of which can negatively impact the heart. Further metabolic changes and cellular damage occur with reperfusion. The altered energy substrate availability prior to organ procurement likely plays an important role in graft quality and post-ischemic cardiac recovery. These aspects should, therefore, be considered in clinical protocols, as well as in pre-clinical DCD models. Notably, interventions prior to graft procurement are limited for ethical reasons in DCD donors; thus, it is important to understand these mechanisms to optimize conditions during initial reperfusion in concert with graft evaluation and re-evaluation for the purpose of tailoring and adjusting therapies and ensuring optimal graft quality for transplantation.

Erratum: Advantages and limitations of clinical scores for donation after circulatory death liver transplantation.

[This corrects the article DOI: 10.3389/fsurg.2021.808733.].

Prolonged warm ischemia time in the recipient is associated with post-transplant biliary stricture following living-donor liver transplantation.

PURPOSE: Post-transplant biliary stricture (PBS) is a common and important complication following orthotopic liver transplantation (LT). This study clarified the incidence of PBS and identified its risk factors. METHODS: We retrospectively reviewed the medical records of 67 patients who underwent living-donor LT (LDLT) at our institute between June 2010 and July 2022 and analyzed their clinical characteristics, prognosis, and risk factors for PBS. RESULTS: Of the 67 patients, 26 (38.8%) developed PBS during the observation period. Multivariate analyses revealed the following independent risk factors for PBS formation: increased red cell transfusion volume per body weight (> 0.2 U/kg; hazard ratio [HR], 3.8; P = 0.002), increased portal vein pressure (PVP) at the end of LT (> 16 mmHg; HR, 2.88; P = 0.032), postoperative biliary leakage (HR, 4.58; P = 0.014), and prolonged warm ischemia time (WIT) (> 48 min; HR, 4.53; P = 0.008). In patients with PBS, the cumulative incidence of becoming stent free was significantly higher in patients with a WIT ≤ 48 min than in those with a WIT > 48 min (P = 0.038). CONCLUSION: Prolonged WIT is associated with intractable PBS following LDLT.

Laparoscopic aspirator bracket: a new instrument facilitating the aspiration and exposure of operative field simultaneously in laparoscopic nephron-sparing surgery.

Background: This study aims to describe a novel laparoscopic aspirator bracket (LAB) and its use in laparoscopic nephron-sparing surgery (NSS) by a simple enucleation (SE) technique. Methods: A total of 123 renal tumor cases who underwent laparoscopic NSS via LAB or laparoscopic aspirator between July 2017 and April 2021 were retrospectively analyzed. General characteristics, perioperative data and postoperative follow-up data of patients were compared. Results: The application of LAB in laparoscopic renal tumor SE surgery shortened the operation time (88.58 ± 38.25 vs. 102.25 ± 35.84 min, p < 0.05) and improved the zero ischemia rate (18.75% vs. 3.39%, p < 0.05), shortened warm ischemia time (16.17 ± 5.16 vs. 19.39 ± 5.62 min, p < 0.05) and decreased intraoperative blood loss (166.19 ± 111.60 vs. 209.15 ± 127.10 ml, p < 0.05). In addition, the serum creatinine and eGFR values in the LAB group also showed faster and better renal function recovery. Conclusion: The new LAB could aspirate and expose the operative field with a single instrument. In operations that need to expose and aspirate simultaneously, such as in renal tumor simple enucleation, it could shorten operation time, reduce intraoperative blood loss and improve the postoperative renal function recovery.

Preliminary feasibility study using a solution of synthetic enzymes to replace the natural enzymes in polyhemoglobin-catalase-superoxide dismutase-carbonic anhydrase: effect on warm ischemic hepatocyte cell culture.

This is a study on a simple solution of chemically prepared small chemical molecules of synthetic enzymes: catalase, superoxide dismutase, and carbonic anhydrase (CAT, SOD, and CA). We carried out a study to see if these synthetic enzymes can replace the natural enzymes (CAT, SOD, and CA) and avoid the need for the complicated cross-linking of natural enzymes to PolyHb to form PolyHb-CAT-SOD-CA. We compared the effect a solution of these three synthetic enzymes has on the viability of warm-ischemic hepatocytes that were exposed to nitrogen for 1 h at 37°C. PolyHb significantly increased the viability. The three synthetic enzymes themselves also significantly increased the viability. The use of both PolyHb and the three synthetic enzymes resulted in an additive effect in the recovery of viability. Increasing the concentration of the synthetic enzymes resulted in further increase in the effect due to the synthetic enzymes. Implications: In addition to PolyHb, there are a number of other HBOC oxygen carriers. However, only Biopure's HBOC product has received regulatory approval, but only in Russia and South Africa. None of the HBOCs has received regulatory approval by other countries. If regulatory agencies require HBOCs to have antioxidant or CO2 transport properties, all that is needed is to add or inject the solution of synthetic enzymes as a separate component.

Are slaughterhouse-obtained livers suitable for use in ex vivo perfusion research?

OBJECTIVES: The success of the ex vivo machine perfusion of pig livers used for preclinical research depends on organ quality and availability. In this study, we investigated whether livers obtained from slaughterhouses are suitable and equivalent to livers obtained from laboratory pigs. METHODS: Livers were obtained from slaughterhouse pigs stunned by electrocution or CO2 inhalation and from laboratory pigs. For the latter group, 45 minutes of warm ischemia was mimicked for a subgroup, ensuring a valid comparison with slaughterhouse-derived livers. RESULTS: Livers from CO2-stunned pigs showed lower indocyanine green clearance and bile production, higher blood lactate and potassium concentrations, and higher alanine aminotransferase activities than electrically stunned pigs. Furthermore, livers from electrically stunned pigs, and livers from laboratory pigs, subjected or not to warm ischemia, showed similar performance in terms of perfusion and metabolism. CONCLUSION: For an ex vivo liver model generated using slaughterhouse pigs, electrical stunning is preferable to CO2 stunning. Livers from electrically stunned slaughterhouse pigs performed similarly to laboratory pig livers. These findings support the use of livers from electrically stunned slaughterhouse pigs, which may therefore provide an alternative to livers obtained from laboratory pigs, consistent with the principle of the 3Rs.

Does tumor rupture during robot-assisted partial nephrectomy have an impact on mid-term tumor recurrences?

BACKGROUND: Intraoperative kidney tumor rupture (TR) can occur during robot-assisted partial nephrectomy (RAPN) in daily clinical practice, but there are no solid guidelines on the management and implications of it. The purpose of the study was to investigate the impact of TR on tumor recurrences, what a surgeon should do if this adverse event occurs, and how to avoid it. PATIENTS AND METHODS: We retrospectively analyzed the first 100 patients who underwent RAPN at University Medical Centre Ljubljana, between 2018 and 2021. Patients were stratified into 2 groups (TR and no-TR) and were compared according to patient, tumor, pathologic, perioperative and postoperative characteristics and tumor recurrences, using the Mann-Whitney U test and chi-squared test. RESULTS: Of the 100 patients, 14 had TR (14%); this occurred in tumors with higher RENAL nephrometry scores (P = 0.028) and mostly with papillary renal cell carcinomas (P = 0.043). Median warm ischemia time was longer for the TR group (22 vs. 15 min, P = 0.026). In terms of studied outcomes, there were no cases of local or distant recurrence after a median observation time of 39 months (interquartile range, 31-47 months) in both groups. We observed positive surgical margins on the final oncologic report in one case in the no-TR group. CONCLUSIONS: Tumor rupture during RAPN seems to be of no mid-term oncologic importance. According to presented results, we would recommend surgeons to proceed with tumor resection if this event occurs and abstain from conversion to radical nephrectomy or open partial nephrectomy. However, more similar cases should be studied to make more solid conclusions.

The effect of warm ischemia and donor ejection fraction on 30-day mortality after donation after circulatory death heart transplantation: A national database analysis.

Donation after circulatory death (DCD) donor hearts recovered using the direct procurement and perfusion method experience variable durations of warm ischemia at the time of procurement (WIP). We used the Organ Procurement and Transplantation Network database to assess the effect of WIP on 30-day mortality after DCD heart transplantation. The analysis evaluated outcomes in 237 recipients of DCD heart transplantation, demonstrating an optimal WIP cut point of <36 minutes. Multivariable logistic regression modeling identified donor left ventricular ejection fraction (LVEF) <60% as an independent predictor of 30-day mortality. The area under the receiver operating characteristic curve for predicting 30-day mortality based on WIP ≥36 minutes and donor LVEF <60% was 0.90. Based on these findings, we do not recommend proceeding with DCD heart transplantation for patients with WIP ≥36 minutes, particularly in donors with LVEF <60%.

The Impact of Combined Warm and Cold Ischemia Time on Post-transplant Outcomes.

Background: Prolonged warm ischemia time (WIT) and cold ischemia time (CIT) are independently associated with post-transplant graft failure; their combined impact has not been previously studied. We explored the effect of combined WIT/CIT on all-cause graft failure following kidney transplantation. Methods: The Scientific Registry of Transplant Recipients was used to identify kidney transplant recipients from January 2000 to March 2015 (after which WIT was no longer separately reported), and patients were followed until September 2017. A combined WIT/CIT variable (excluding extreme values) was separately derived for live and deceased donor recipients using cubic splines; for live donor recipients, the reference group was WIT 10 to <23 minutes and CIT >0 to <0.42 hours, and for deceased donor recipients the WIT was 10 to <25 minutes and CIT 1 to <7.75 hours. The adjusted association between combined WIT/CIT and all-cause graft failure (including death) was analyzed using Cox regression. Secondary outcomes included delayed graft function (DGF). Results: A total of 137 125 recipients were included. For live donor recipients, patients with prolonged WIT/CIT (60 to ≤120 minutes/3.04 to ≤24 hours) had the highest adjusted hazard ratio (HR) for graft failure (HR = 1.61, 95% confidence interval [CI] = 1.14-2.29 relative to the reference group). For deceased donor recipients, a WIT/CIT of 63 to ≤120 minutes/28 to ≤48 hours was associated with an adjusted HR of 1.35 (95% CI = 1.16-1.58). Prolonged WIT/CIT was also associated with DGF for both groups although the impact was more driven by CIT. Conclusions: Combined WIT/CIT is associated with graft loss following transplantation. Acknowledging that these are separate variables with different determinants, we emphasize the importance of capturing WIT and CIT independently. Furthermore, efforts to reduce WIT and CIT should be prioritized.

Contexte: La période prolongée d'ischémie à chaud (WIT­warm ischemia time) et la période prolongée d'ischémie à froid (CIT­cold ischemia time) ont été associées de façon indépendante à une défaillance du greffon post-transplantation, mais leur effet combiné n'a jamais été étudié. Nous avons examiné l'effet combiné WIT/CIT sur la défaillance du greffon toutes causes confondues après une transplantation rénale. Méthodologie: Le Scientific Registry of Transplant Recipients a été utilisé pour identifier les receveurs d'une greffe de rein entre janvier 2000 et mars 2015 (date après laquelle la WIT n'a plus été rapportée séparément). Les patients ont été suivis jusqu'en septembre 2017. Une variable combinée WIT/CIT (excluant les valeurs extrêmes) a été dérivée de façon isolée pour les donneurs vivants et les donneurs décédés à l'aide d'une fonction spline cubique. La WIT du groupe référence pour les donneurs vivants se situait entre 10 et <23 minutes, et la CIT entre 0 et <0,42 heure; pour les donneurs décédés, la WIT se situait entre 10 et <25 minutes, et la CIT entre 1 et <7,75 heures. L'association corrigée entre une combinaison WIT/CIT et la défaillance du greffon toutes causes confondues (y compris le décès) a été analysée à l'aide de la régression de Cox. Les résultats secondaires incluaient une reprise retardée de la fonction du greffon (RRFG). Résultats: Un total de 137 125 receveurs d'un rein a été inclus. Dans le groupe des receveurs d'un organe provenant d'un donneur vivant, les patients avec une WIT/CIT prolongée (60 à ≤120 minutes/3,04 à ≤24 heures) présentaient un risque relatif corrigé plus élevé de défaillance du greffon (RRc: 1,61; IC 95 %: 1,14-2,29) par rapport au groupe de référence. Dans le groupe des receveurs d'un organe provenant d'un donneur décédé, une combinaison WIT/CIT de 63 à ≤120 minutes/28 à ≤48 heures a été associée à un RRc de 1,35 (IC 95 %: 1,16-1,58). La WIT/CIT prolongée a également été associée à une RRFG pour les deux groupes, bien que cet effet ait été davantage influencé par la CIT. Conclusion: La combinaison WIT/CIT est associée à la perte du greffon après la transplantation. Sachant qu'il s'agit de variables distinctes avec des déterminants différents, nous soulignons l'importance de rapporter la WIT et la CIT de façon indépendante. Qui plus est, les efforts visant à réduire la WIT et la CIT devraient être prioritaires.

Warm Ischemia Induces Spatiotemporal Changes in Lysophosphatidylinositol That Affect Post-Reperfusion Injury in Normal and Steatotic Rat Livers.

Warm ischemia-reperfusion injury is a prognostic factor for hepatectomy and liver transplantation. However, its underlying molecular mechanisms are unknown. This study aimed to elucidate these mechanisms and identify the predictive markers of post-reperfusion injury. Rats with normal livers were subjected to 70% hepatic warm ischemia for 15, 30, or 90 min, while those with steatotic livers were subjected to 70% hepatic warm ischemia for only 30 min. The liver and blood were sampled at the end of ischemia and 1, 6, and 24 h after reperfusion. The serum alanine aminotransferase (ALT) activity, Suzuki injury scores, and lipid peroxidation (LPO) products were evaluated. The ALT activity and Suzuki scores increased with ischemic duration and peaked at 1 and 6 h after reperfusion, respectively. Steatotic livers subjected to 30 min ischemia and normal livers subjected to 90 min ischemia showed comparable injury. A similar trend was observed for LPO products. Imaging mass spectrometry of normal livers revealed an increase in lysophosphatidylinositol (LPI (18:0)) and a concomitant decrease in phosphatidylinositol (PI (18:0/20:4)) in Zone 1 (central venous region) with increasing ischemic duration; they returned to their basal values after reperfusion. Similar changes were observed in steatotic livers. Hepatic warm ischemia time-dependent acceleration of PI (18:0/20:4) to LPI (18:0) conversion occurs initially in Zone 1 and is more pronounced in fatty livers. Thus, the LPI (18:0)/PI (18:0/20:4) ratio is a potential predictor of post-reperfusion injury.

Toll-Like Receptor 4 Induction During Renal Ischemia Correlates with Serum Creatinine in a Pig Model.

Objectives: To determine whether toll-like receptor 4 (TLR4), a mediator of organ ischemia-reperfusion injury, is overexpressed during warm ischemia in a porcine solitary kidney model, and whether its expression correlates with creatinine, a surrogate for kidney function. Materials and Methods: Eight adult Yorkshire pigs underwent initial laparoscopic nephrectomy. After 1 week, animals were randomized into two groups: group 1 underwent laparoscopic renal hilar dissection, renal ischemia by cross-clamping, and reperfusion (ischemia group); group 2 underwent laparoscopic renal hilar dissection alone (sham group). Animals were survived to day 7 postrandomization. Peripheral blood was sampled for serum creatinine (sCr) and TLR4 expression at the following time points or corresponding intervals: prenephrectomy, 1-week postnephrectomy (preischemia), after 90 minutes of ischemia, 30 minutes postreperfusion, and at sacrifice. Intragroup TLR4 expression changes were analyzed using repeated measures ANOVA. Intergroup TLR4 expression was compared using Mann-Whitney's test. Correlation between sCr and TLR4 was assessed using Spearman's test. Results: Seven animals completed the experiment (four ischemia and three sham). Relative TLR4 expression significantly increased from baseline levels during ischemia, reperfusion, and sacrifice time points only in the ischemia group, and was significantly higher for the ischemia group after 90 minutes of ischemia (p = 0.034). sCr was significantly higher for the ischemia group during the reperfusion phase (p = 0.048). Relative TLR4 expression level significantly correlated with sCr in the overall cohort (Spearman's rho = 0.69) and in the ischemia group (Spearman's rho = 0.82; p < 0.0001 for each). Conclusions: Warm ischemia in a porcine solitary kidney induces acute overexpression of TLR4 in peripheral blood leukocytes, which is detectable. Relative TLR4 expression level strongly correlated with sCr but had an observable change sooner than change in sCr. Pending further investigation, TLR4 overexpression during renal ischemia may represent a sensitive quantitative marker of unilateral renal injury sustained during nephron-sparing surgery.

The role of warm ischemia time on functional outcomes after robotic partial nephrectomy: a radionuclide renal scan study from the clock randomized trial.

PURPOSE: To evaluate the relationship between warm ischemia time (WIT) duration and renal function after robot-assisted partial nephrectomy (RAPN). METHODS: The CLOCK trial is a phase 3 randomized controlled trial comparing on- vs off-clamp RAPN. All patients underwent pre- and postoperative renal scintigraphy. Six-month absolute variation of eGFR (AV-GFR), rate of relative variation in eGFR over 25% (RV-GFR > 25), absolute variation of split renal function (SRF) at scintigraphy (AV-SRF). The relationships WIT/outcomes were assessed by correlation graphs and then modeled by uni- and multivariable regression. RESULTS: 324 patients were included (206 on-clamp, 118 off-clamp RAPN). Correlation graphs showed a threshold on WIT equal to 10 min. The differences in outcome measures between cases with WIT < vs ≥ 10 min were: AV-GFR - 3.7 vs - 7.5 ml/min (p < 0.001); AV-SRF - 1% vs - 3.6% (p < 0.001); RV-GFR > 25 9.3% vs 17.8% (p = 0.008). Multivariable models found that AV-GFR was related to WIT ≥ 10 min (regression coefficient [RC] - 0.52, p = 0.019), age (RC - 0.35, p = 0.001) and baseline eGFR (RC - 0.30, p < 0.001); RV-GFR > 25 to WIT ≥ 10 min (odds ratio [OR] 1.11, p = 0.007) and acute kidney injury defined as > 50% increase in serum creatinine (OR 19.7, p = 0.009); AV-SRF to WIT ≥ 10 min (RC - 0.30, p = 0.018), baseline SRF (RC - 0.76, p < 0.001) and RENAL score (RC - 0.60. p = 0.028). The main limitation was that the CLOCK trial was designed on a different endpoint and therefore the present analysis could be underpowered. CONCLUSIONS: Up to 10 min WIT had no consequences on functional outcomes. Above the 10-min threshold, a statistically significant, but clinically negligible impact was found.

A Review of Machine Perfusion Strategies in Liver Transplantation.

The acceptance of liver transplantation as the standard of care for end-stage liver diseases has led to a critical shortage of donor allografts. To expand the donor organ pool, many countries have liberalized the donor criteria including extended criteria donors and donation after circulatory death. These marginal livers are at a higher risk of injury when they are preserved using the standard static cold storage (SCS) preservation techniques. In recent years, research has focused on optimizing organ preservation techniques to protect these marginal livers. Machine perfusion (MP) of the expanded donor liver has witnessed considerable advancements in the last decade. Research has showed MP strategies to confer significant advantages over the SCS techniques, such as longer preservation times, viability assessment and the potential to recondition high risk allografts prior to implantation. In this review article, we address the topic of MP in liver allograft preservation, with emphasis on current trends in clinical application. We discuss the relevant clinical trials related to the techniques of hypothermic MP, normothermic MP, hypothermic oxygenated MP, and controlled oxygenated rewarming. We also discuss the potential applications of ex vivo therapeutics which may be relevant in the future to further optimize the allograft prior to transplantation.

Identification of predictive factors for outcomes after robot-assisted partial nephrectomy based on three-dimensional reconstruction of preoperative enhanced computerized tomography.

Background: Information from the RENAL score is limited. This study aimed to identify new parameters based on three-dimensional (3D) reconstruction of preoperative enhanced computerized tomography (CT) for predicting outcomes after robot-assisted partial nephrectomy (RPN). Materials and methods: The records of kidney cancer patients who underwent RPN at Tongji Hospital from March 2015 to July 2019 were reviewed. Demographic data, laboratory examinations, postoperative hospitalization time, and enhanced CT were retrospectively collected. Some tumor parameters were obtained from 3D reconstruction of CT data. The association between these predictive factors and outcomes after RPN was analyzed. Results: A larger tumor bed area (TBA) was associated with a longer warm ischemia time (WIT) (P-value <0.001) and tumor resection time (P-value <0.001). Moreover, TBA was significantly associated with the elevation of postoperative creatinine (P-value = 0.005). TBA (P = 0.008), distance from the tumor to the first bifurcation of the renal artery (DTA) (P <0.034), and RENAL score (P = 0.005) were significantly associated with WIT in univariate logistic regression. In multivariate logistic regression, TBA (P = 0.026) and DTA (P = 0.048) were independent risk factors for prolonged WIT (over 25 min). The predictive effect of the combination of TBA, DTA, and RENAL score was higher than the predictive effect of RENAL score alone for WIT (area under curve: 0.786 versus 0.72). Conclusion: TBA and DTA are independently associated with the WIT of RPN, which provides additional assessment value for the complexity of kidney cancer in RPN over the RENAL score.

Laparoscopic Living Donor Nephrectomy: A Single Center Comparison of Three Different Techniques.

Background and Objectives: In this study, we compare three different surgical approaches at a single institution. Pure laparoscopic donor nephrectomy with Pfannenstiel incision (PLDN) was compared with hand-assisted laparoscopic donor nephrectomy via midline hand port (HALDNM) and hand-assisted laparoscopic donor nephrectomy via left iliac hand port (HALDNL). Methods: This study included all laparoscopic left donor nephrectomies performed at our institution between January 1, 2020 and December 31, 2021. Donor characteristics including age, sex, body mass index, number of renal arteries, duration of surgical procedure, warm ischemia time (WIT), and length of hospital stay were compared. Cosmetic scores were calculated by totaling the length of all incisions placed. Postoperative complications within 90 days were compared. Results: During the study period 71 laparoscopic donor nephrectomies were performed of which 26 were HALDNM, 24 were HALDNL, and 21 were PLDN. Donor characteristics were similar in all three groups. Total operative time was significantly lower in HALDNM (181 minutes) than PLDN (233 minutes) and HALDNL (242 minutes) (p < 0.001). The WIT was comparable in all three groups: HALDNL (7.2 minutes), PLDN (4.1 minutes), and HALDM (4.9 minutes) (p = 0.913). Median cosmetic score was significantly better in the PLDN group (8.2 cm) when compared to HALDNM (11.1 cm) and HALDNL (9.9 cm) (p < 0.001). Conclusion: Our results show that all three technical modifications of laparoscopic donor nephrectomy are safe and feasible with good postoperative outcomes. HALDNM has the added benefit of decreased operative time while PLDN has a cosmetic advantage.