Vascular Clamp Research Articles

Analysis of two reperfusion techniques in uterine transplantation in an experimental model.

Uterine transplantation was developed for the treatment of absolute uterine factor infertility. As it is a new modality of transplantation, there is still room for technical improvement. A factor that impacts graft survival in organ transplantation is the warm ischemia time. In uterine transplantation specifically, at least two vascular anastomoses are performed on each side of the uterus, and the graft revascularization takes place when the vascular clamps of the arteries and veins are released on both sides simultaneously. For this reason, the warm ischemia time in uterine transplant is expected to be considerably long. The purpose of this study was to compare the sequential technique of uterine graft revascularization, which aims to reduce the warm ischemia time of the procedure, with the simultaneous revascularization technique. For the procedure, the uterine auto-transplantation technique was performed using 10 non-pregnant adult ewes weighing about 45 kg, divided into two groups: simultaneous revascularization group (5 animals) and sequential revascularization group (5 animals). To evaluate the groups, we analyzed the procedure and warm ischemia times, graft macroscopy, hemodynamic, laboratory, and histological parameters of the uterus. The sequential revascularization technique group had similar surgical procedure times, and the warm ischemia time was significantly shorter with medians of 32 min in the sequential group versus 72 min in the simultaneous group (p < 0.008). The graft macroscopy and hemodynamic, laboratory, and histological parameters evaluated were similar between the groups. The sequential revascularization technique proved to reduce the warm ischemia time in the sheep uterine auto-transplantation model without compromising graft viability.

Exendin-4 promotes ischemia-reperfusion flap survival by upregulating Gpx4 to inhibit ferroptosis

BackgroundEffective drugs for preventing or treating skin flap necrosis remain elusive. In this study, we investigated the potential protective effect of exendin-4 against skin flap ischemia-reperfusion injury (IRI) through the inhibition of ferroptosis. MethodA rat abdomen was constructed with an island skin flap, and the superficial vascular pedicle of the abdominal wall was closed using a vascular clamp, which was removed after 8 h. Before surgery, RSL3 and ferrostatin-1 solutions were intraperitoneally injected. After the surgery, subcutaneous injections of exendin-4 were administered daily. The number of inflammatory cells, mean vascular density, collagen fiber content, and apoptosis and ferroptosis indicators were quantified 24 h after reperfusion. Survival, contraction rate, and blood perfusion of the skin flap were evaluated on days 1, 3, 5, and 7 after reperfusion. ResultsThe flap survival rate was significantly higher in the exendin-4 group than that in the injury group, whereas the contraction rate was lower. Compared with the injury group, the exendin-4 group showed less inflammatory cell infiltration, higher vascular density, and less collagen fiber loss. At the molecular level, the exendin-4 group demonstrated opposite or elevated expression of apoptosis and ferroptosis indicators than those in the injury group, with significantly increased glutathione peroxidase 4 (Gpx4). Ferroptosis inhibitors and agonists enhanced and reversed the protective effects of exendin-4, respectively. ConclusionExendin-4 alleviates skin flap IRI by upregulating Gpx4 expression to inhibit ferroptosis. Therefore, exendin-4 may serve as a novel clinical treatment for skin flap IRI.

Optimization design and performance study of magnesium alloy vascular clamp

Purpose: This study investigates the effects of varying inner diameter of a vascular clamp made from an Mg–Nd–Zn–Zr alloy on its functional performance. The primary objectives are to optimize the clamp’s structure, assess its performance across different inner diameters, and ultimately determine the optimal configuration. Methods: We developed a V-shaped vascular clamp equipped with a locking mechanism and transverse teeth. The study involved comparing vascular clamps with various inner diameters (0.35 mm, 0.4 mm, 0.5 mm and 0.6 mm, denoted as R0.35, R0.4, R0.5 and R0.6, respectively), achieved by modifying the clamp design. Finite element analysis simulated the closure process of these clamps, both with and without blood vessels, to analyze stress and strain distribution. Subsequently, we manufactured a clamp with the optimized design and conducted performance evaluations, including a closing strength test and an in vitro immersion test. Results: Among the tested vascular clamps, the R0.5 clamp demonstrated the lowest strain (0.50798) and minimal stress on blood vessels (0.7629 MPa). Notably, the R0.5 clamp remained intact during clamping fracture experiments and demonstrated a maximum closing force of 334.98±15.4 mmHg. Regarding corrosion resistance, the clamped position showed a higher corrosion rate (0.179±0.00551 mg.cm-2.day-1) compared to the open clamp (0.161±0.00306 mg.cm-2.day-1). Conclusion: The R0.5 clamp demonstrated superior performance in finite element analysis, showing effective vascular closure, strong clamping force, and uniform corrosion behavior. Overall, these results highlight its potential as an effective tool for vascular closure.

Robot-assisted Partial Nephrectomy for Hilar and Nonhilar Renal Masses: Comparison of Perioperative, Oncological, and Functional Results in a Multicentre Prospective Cohort (NEPRAH Study, UroCCR 175)

Background and objectiveA hilar location for a renal tumour is sometimes viewed as a limiting factor for safe partial nephrectomy. Our aim was to evaluate perioperative, oncological, and functional outcomes of robot-assisted partial nephrectomy (RAPN) for hilar tumours (RAPN-H) in comparison to RAPN for nonhilar tumours (RAPN-NH). MethodsWe conducted an observational, multicentre cohort study using prospectively collected data from the French Research Network on Kidney Cancer (UroCCR). The registry includes data for 3551 patients who underwent RAPN for localised or locally advanced renal masses between 2010 and 2023 in 29 hospitals in France. We studied the impact of a hilar location on surgery, postoperative renal function, tumour characteristics, and survival. We also compared rates of trifecta achievement (warm ischaemia time [WIT] <25 min, negative surgical margins, and no perioperative complications) between the groups. Finally, we performed a subgroup analysis of RAPN without vascular clamping. Variables were compared in univariable analysis and using multivariable linear, logistic, and Cox proportional-hazards models adjusted for relevant patient and tumour covariates. Key findings and limitationsThe analytical population included 3451 patients, of whom 2773 underwent RAPN-NH and 678 underwent RAPN-H. Longer WIT (β = 2.4 min; p < 0.01), longer operative time (β = 11.4 min; p < 0.01) and a higher risk of postoperative complications (odds ratio 1.33; p = 0.05) were observed in the hilar group. Blood loss, the perioperative transfusion rate, postoperative changes in the estimated glomerular filtration rate, and trifecta achievement rates were comparable between the groups (p > 0.05). At mean follow-up of 31.9 mo, there was no significant difference in recurrence-free survival (hazard ratio [HR] 0.82, 95% confidence interval [CI] 0.58–1.2; p = 0.3), cancer-specific survival (HR 1.1, 95% CI 0.48–2.6; p = 0.79), or overall survival (HR 0.89, 95% CI 0.52–1.53; p = 0.69). Conclusions and clinical implicationsPatient and tumour characteristics rather than just hilar location should be the main determinants of the optimal surgical strategy for hilar tumours. Patient summaryWe found that kidney tumours located close to major kidney blood vessels led to a longer operation and a higher risk of complications during robot-assisted surgery to remove the tumour. However, tumours in these locations were not related to a higher risk of kidney function loss, cancer recurrence, or death.

#337 Renal 3D photoacoustic imaging and contrast-enhanced ultrasound to assess oxygenation and perfusion and to predict fibrosis after ischemia-reperfusion

Abstract Background and Aims Renal 3D photo-acoustic imaging (3D-PAI) and contrast-enhanced ultrasound (CEUS) are promising tools in mice models to assess repeatedly and non-invasively renal ischemia-reperfusion (RIR) consequences and damages, or their improvement by nephroprotective strategies like mild therapeutic hypothermia (mTH), at the early phase of reperfusion as well as in the chronic late phase. Method C57Bl6 mice underwent 15 minutes of unilateral renal vascular clamping, with body temperature at 37°C (RIR-37°C, n=7) or mTH at 34°C (RIR-34°C, n=7), or a sham procedure (Sham, n=5). Renal volume and oxygen saturation (sO2-3D; corresponding to the percentage of oxyhemoglobin over the total hemoglobin content) were measured with 3D-PAI (3D reconstruction of the whole kidney through multi-plane acquisition with an automatized mobile support), and renal perfusion parameters (rBV, mTT, rBF) with CEUS (“destruction-replenishment” model of intravenous microbubbles), performed with VEVO3100 echograph (Fujifilm Visualsonic) 1 week before RIR (basal), 20 minutes after reperfusion, and 1 month after. Renal fibrosis was quantified at 1 month with Masson's trichrome coloration on histological samples. Data were compared with Mann-Whitney test or Wilcoxon test (paired data) as appropriate. Correlation was tested by Spearman test. All animal procedures were approved by the Ethics Committee. Results Sham showed no significant changes during follow-up. RIR-37°C led to renal hypotrophy (volume on 3D-PAI) and fibrosis at 1 month, compared to RIR-34°C (median volume 76 IQR [71-119] vs 143 IQR[108-180] mm3; p=0.03), and those parameters were correlated (R=−0.49; p=0.03). In RIR-37°C, sO2-3D tended to lower at 20 minutes compared to basal values (median sO2-3D 37 IQR [37-44] vs 49 IQR [36-57]%; p=0.08), but not in RIR-34°C (p &amp;gt; 0.99), and these early variations of sO2-3D were correlated with fibrosis at 1 month (R=−0.48; p=0.04). Renal perfusion was altered in RIR-37°C at 20 minutes compared to basal values (median rBV 73 IQR [46-105] vs 100 IQR [89-126] a.u.; p=0.047), and remained altered at 1 month (median rBV 71 IQR [57-83] a.u.; p=0.03), but not in RIR-34°C (p=0.47 at both 20 minutes and 1 month). Renal perfusion early alterations at 20 minutes were correlated with late alterations at 1 month (R=0.63; p=0.005), and tended to correlate with fibrosis (R=−0.41; p=0.08). Conclusion Renal 3D-PAI (on the whole 3D-reconstructed kidney) and CEUS can detect early alterations of renal perfusion and oxygen saturation after RIR, and predict chronic disturbances of perfusion and the onset of fibrosis, as well as the protection conferred by mTH. 3D-PAI can also be used to evaluate non-invasively renal volume as a surrogate of renal fibrosis after RIR.

Intraoperative Renal Artery Thrombosis of the Transplanted Kidney Secondary to Intimal Injury

Vascular complications after renal transplantation are rare, however, they are serious surgical complications. Intimal tears in the renal arteries can result from iatrogenic injuries. These injuries can occur due to crushing injuries of the intima secondary to the use of improper vascular clamps, mishandling of the vessels, and use of traumatic infusion/perfusion needles or devices. It is important to recognize these intimal injuries so that corrective measures can be undertaken immediately and avoid vascular complications. We report a case of renal artery thrombosis secondary to intimal injury leading to intraoperative poor blood flow across the anastomosis which was promptly recognized and corrected leading to successful salvage of the transplanted kidney.

Safety of perioperative intravenous lidocaine in liver surgery - A pilot study.

Perioperative lidocaine infusion has many interesting properties such as analgesic effects in the context of enhanced recovery after surgery. However, its use is limited in liver surgery due to its hepatic metabolism. This prospective, monocentric study was conducted from 2020 to 2021. Patients undergoing liver surgery were included. They received a lidocaine infusion protocol until the beginning of hepatic transection (bolus dose of 1.5 mg kg-1, then a continuous infusion of 2 mg kg-1 h-1). Plasma concentrations of lidocaine were measured four times during and after lidocaine infusion. Twenty subjects who underwent liver resection were analyzed. There was 35% of preexisting liver disease before tumor diagnosis, and 75% of liver resection was defined as "major hepatectomy." Plasmatic levels of lidocaine were in the therapeutic range. No blood sample showed a concentration above the toxicity threshold: 1.6 (1.3-2.1) μg ml-1 one hour after the start of infusion, 2.5 (1.7-2.8) μg ml-1 at the end of hepatic transection, 1.7 (1.3-2.0) μg ml-1 one hour after the end of infusion, and 1.2 (0.8-1.4) μg ml-1 at the end of surgery. Comparative analysis between the presence of a preexisting liver disease or not and the association of intraoperative vascular clamping or not did not show significant difference concerning lidocaine blood levels. Perioperative lidocaine infusion seems safe in the field of liver surgery. Nevertheless, additional prospective studies need to assess the clinical usefulness in terms of analgesia and antitumoral effects.

Totally percutaneous endovascular renal allograft salvage for common iliac artery pseudoaneurysm

Delayed presentation of recipient artery pseudoaneurysms following kidney transplantation is a rare, yet critical, complication. Although the precise etiology remains unclear, factors such as chronic steroid use, iatrogenic injuries (including vascular clamp damage during index surgery), or infections could contribute. Timely surgical intervention is imperative to prevent arterial rupture and life-threatening bleeding. Open repair, although commonly used, is associated with notable mortality rates and graft loss. Endovascular repair for delayed presentations of native iliac artery pseudoaneurysms has seen limited documentation in the literature. We present a case involving salvage of a kidney graft through innovative application of an endovascular technique using a modified stent graft with fenestration for the transplanted renal artery. The pseudoaneurysm, discovered 4 years after transplantation, was situated in proximity to the anastomosis site of the kidney graft’s renal artery to recipient common iliac artery. Traditional open repair posed significant risks of graft loss due to its location near the kidney allograft. Our approach successfully resolved the issue, preserving graft function and resulting in a short length of hospital stay. This case contributes to the limited body of knowledge on delayed presentation of pseudoaneurysms after kidney transplantation. Successful application of an endovascular approach underscores its potential as a safe and effective alternative to open repair, offering favorable outcomes in terms of patient morbidity, mortality, and graft salvage.

A Detailed Exploration of the Ex Utero Intrapartum Treatment Procedure with Center-Specific Advancements

The Ex Utero Intrapartum Treatment (EXIT) procedure has long been an invaluable tool in managing complex fetal conditions requiring airway interventions during the transition from intrauterine to extrauterine life. This technical note offers an in-depth examination of the EXIT procedure, emphasizing the refinements and innovations introduced at our center. The technique focuses on meticulous preoperative assessment and uses distinctive techniques and anesthetic methodologies. A multidisciplinary team assembles to plan the EXIT procedure, emphasizing patient communication and risk discussion. Our technique involves atraumatic access to the uterine cavity, achieved through the application of a uterine progressive distractor developed for this purpose. Following the use of this distractor, vascular clamps and a stapling device (Premium Poly Cs-57 Autosuture®, Medtronic) are employed. Our anesthetic approach employs general anesthesia with epidural catheter placement. Maternal operation involves low transverse laparotomy and intraoperative ultrasonography-guided hysterotomy. Fetal exposure includes gentle extraction or external version, ensuring airway access. After securing fetal airway access, umbilical cord clamping and maternal abdominal closure conclude the procedure. By revisiting the core principles of EXIT and incorporating center-specific advancements, we enhance our understanding and technical expertise. To our knowledge, this is the first time a detailed description of the technique has been published.

Acute Hypoxia Does Not Alter Tumor Sensitivity to FLASH Radiation Therapy

Tumor hypoxia is a major cause of treatment resistance, especially to radiation therapy at conventional dose rate (CONV), and we wanted to assess whether hypoxia does alter tumor sensitivity to FLASH. We engrafted several tumor types (glioblastoma [GBM], head and neck cancer, and lung adenocarcinoma) subcutaneously in mice to provide a reliable and rigorous way to modulate oxygen supply via vascular clamping or carbogen breathing. We irradiated tumors using a single 20-Gy fraction at either CONV or FLASH, measured oxygen tension, monitored tumor growth, and sampled tumors for bulk RNAseq and pimonidazole analysis. Next, we inhibited glycolysis with trametinib in GBM tumors to enhance FLASH efficacy. Using various subcutaneous tumor models, and in contrast to CONV, FLASH retained antitumor efficacy under acute hypoxia. These findings show that in addition to normal tissue sparing, FLASH could overcome hypoxia-mediated tumor resistance. Follow-up molecular analysis using RNAseq profiling uncovered a FLASH-specific profile in human GBM that involved cell-cycle arrest, decreased ribosomal biogenesis, and a switch from oxidative phosphorylation to glycolysis. Glycolysis inhibition by trametinib enhanced FLASH efficacy in both normal and clamped conditions. These data provide new and specific insights showing the efficacy of FLASH in a radiation-resistant context, proving an additional benefit of FLASH over CONV.

A modified technique for arteriovenous fistula anastomosis: Preserving the surrounding tissue of the vein without the use of vascular clamps

Background: This pilot study describes a new technique for creating an arteriovenous fistula (AVF) and presents the preliminary outcomes after 1 year of follow-up. Methods: The study included 19 patients (10 males, 9 females) with a mean age of 62 years (range 26–88 years). All patients received an AVF using a modified technique in which the surrounding tissues were not removed from the veins and no elastic loops or vascular clamps were used. Results: Immediate patency was obtained for all patients. The proportion of patients experiencing primary patency at 30 days and 6 months was 89.5% and 83.1%, respectively, and cumulative patency at 30 days and 6 months was 100%. At 1 year of follow-up, primary patency was 83.1% and cumulative patency was 100%. Conclusions: Complete preservation of the surrounding venous tissue in the absence of vascular clamps successfully established AVF, with a high surgical success rate.

Comparison of imaging changes in pulmonary artery diameter at the occlusion site using silk or metal clamps for pulmonary artery troubles.

We analysed our clinical experience using silk sutures [the double-loop technique (DLT)] or DeBakey type vascular clamp (DeBakey clamp) for pulmonary artery (PA) troubles during anatomical lung resection to validate its practicality and safety. We retrospectively reviewed the records of patients who underwent either of the above clamping techniques during anatomical lung resection at our hospital between April 2007 and August 2022. We measured the PA diameter at the occlusion site on computed tomography images acquired within 1 year pre- and postoperatively. The difference between pre- and postoperative diameters of the occlusion sites was calculated as the change in the PA diameter. We zoned the occlusion site of the PA to adjust for variation. PA deformation was evaluated as an adverse event caused by clamping. Ultimately, 27 and 26 patients who underwent the DLT and DeBakey clamp, respectively, were included. No additional injury due to the clamp procedure was found in either group. For zone R1/L1, defined as the main PA, the median changes in the PA diameter were 0.02 (-0.7 to 0.27) mm for the DLT and 0.36 (-0.28 to 0.89) mm for the DeBakey clamp. No significant differences were observed between the 2 groups (P = 0.106). Furthermore, no aneurysms, dissections, or stenoses were found in either group. The DLT and DeBakey clamp had only minimal effects on the occlusion site of the PA. The DLT is a practical thoracoscopic technique for PA bleeding when primary haemostasis has been achieved.

Long-Term Protective Effects of Lamotrigine in a Rat Ovarian Ischemia-Reperfusion Model

Ovarium torsion is a gynecological emergency that is common in women of reproductive age and requires early diagnosis and intervention. In this study, we aimed to investigate the long-term anatomical, histological and biochemical protective effects of lamotrigine in ovariums in the ischemia – reperfusion (I–R) model created experimentally in rats. A total of 40 female Sprague-Dawley rats, 14 weeks old, weighing 220-270 grams were used in the study. The subjects were randomly distributed to form 4 groups named SHAM group, I - R group, I - R + Lamotrigine (LTG) group and R + LTG group. Under general anesthesia, the ovaries of the rats were reached and ischemia was created for 3hours with vascular clamps. 20mg / kg LTG was administered intraperitoneally (ip.) to group 3 30minutes before ischemia and to group 4 30minutes before reperfusion. At the third hour of ischemia, the vascular clamps were opened and the abdomen of the rats was closed according to the surgical procedure. The rats were followed up for 28 days postoperatively and the ovarium tissues taken on the 28th day were examined anatomically and histologically. Biochemically, estradiol (E2), follicle stimulating hormone (FSH) and antimullerian hormone (AMH) levels were measured from blood samples taken from their hearts. Granulosa cells with diffuse vaculations were observed in degenerative follicles in group I-R. Again in this group, severe hemorrhage, fibrosis and edematous areas were observed in the ovarium stroma (Ovarian Histopathological Scoring (OHS): 7). In the I - R + LTG group, OHS was statistically significantly lower than the I - R group (OHS: 2; p <0.000). In the R + LTG group, although the OHS score was calculated to be lower than the I - R group, there was no statistically significant difference (OHS: 6; p> 0.05). The protective effect of LTG against experimentally created ischemia and reperfusion damage was determined anatomically and histologically. No protective effect of LTG was observed in terms of FSH, E2 and AMH values measured from the blood sera of rats. These findings may provide a basis for future studies using LTG to treat ovarian ischemia-reperfusion injury.

Pulmonary artery sarcoma and severe valvular diseases in late-septuagenarian women: was 2-stage surgery an appropriate strategy? A case report

BackgroundPulmonary artery sarcomas (PASs) are rare, and complete tumor resection is often difficult at the time of detection. We encountered a case of PAS that was thought to be resectable; however, the patient had severe symptomatic valvular disease. We faced a difficult decision regarding the surgical strategy.Case presentationA 76-year-old female presented with a history of polysurgery for multiple primary cancers. She was referred to our department with a calcified mass in the right pulmonary artery (PA) and severe symptomatic valvular disease. After a discussion with the cardiovascular surgeon, we decided to perform a two-stage surgery. She underwent valvuloplasty through a median sternotomy, resulting in an improvement in her exertional dyspnea. The tumor was removed three months later with a right upper lobectomy and PA patch reconstruction through a posterolateral thoracotomy. When the PA was opened, the edge of the tumor was entrapped by vascular clamp forceps because of insufficient dissection of the adhesions between the superior vena cava and the right main PA resulting from the first operation. The patient underwent proton therapy twice for chest wall metastases which recurred three months after surgery, and local recurrence in the PA was diagnosed five months after surgery. The patient was alive with stable disease 25 months after surgery.ConclusionTwo-stage surgery for PAS and valvular disease resulted in incomplete resection of the PAS in the right PA. It is important not to underestimate surgical adhesions due to the initial surgery and to consider and implement measures to prevent adhesions of critical vessels during the second operation.

Rehabilitation training enhanced the therapeutic effect of calycosin on neurological function recovery of rats following spinal cord injury

BackgroundCalycosin (CA), a flavonoids component, has demonstrated potential neuroprotection effects by inhibiting oxidative stress in spinal cord injury (SCI) models. This study aims to investigate the impact of combined rehabilitation training (RT) and calycosin therapy on neurological function following SCI, primarily by assessing changes in motor function recovery, neuronal survival, neuronal oxidative stress levels, and neural proliferation, in order to provide novel insights for the treatment of SCI. Materials and MethodsThe SCI model was constructed by compressing the spinal cord using vascular clamps. Calycosin was injected intraperitoneally into the SCI model rats, and a group of 5 rats underwent RT. The motor function of rats after SCI was evaluated using the Basso Beattle Bresnaha (BBB) score and the inclined plate test. Histopathological changes were evaluated by NeuN immunohistochemistry, HE and Nissl staining. Apoptosis was detected by TUNEL staining. The antioxidant effect of combined treatment was assessed by measuring changes in oxidative stress markers after SCI. Western blot analysis was conducted to examine changes in Hsp90-Akt/ASK1-p38 pathway-related proteins. Finally, cell proliferation was detected by BrdU and Ki67 assays. ResultsRT significantly improved the BBB score and angle of incline promoted by calycosin, resulting in enhanced motor function recovery in rats with SCI. Combining rehabilitation training with calycosin has a positive effect on morphological recovery. Similarly, combined RT enhanced the Nissl and NeuN staining signals of spinal cord neurons increased by calycosin, thereby increasing the number of neurons. TUNEL staining results indicated that calycosin treatment reduced the apoptosis signal in SCI, and the addition of RT further reduced the apoptosis. Moreover, RT combined with calycosin reduced oxidative stress by increasing SOD and GSH levels, while decreasing MDA, NO, ROS, and LDH expressions compared to the calycosin alone. RT slightly enhanced the effect of calycosin in activating Hsp90 and Akt and inhibiting the activation of ASK1 and p38, leading to enhanced inhibition of oxidative stress by calycosin. Additionally, the proliferation indexes (Ki67 and BrdU) assays showed that calycosin treatment alone increased both, whereas the combination treatment further promoted cell proliferation. ConclusionOur research findings demonstrate that rehabilitation training enhances the ability of calycosin to reduce oxidative stress, resulting in a decrease in neuronal apoptosis and an increase in proliferation, ultimately promoting neuronal survival.

Methane-Rich Saline Suppresses ER-Mitochondria Contact and Activation of the NLRP3 Inflammasome by Regulating the PERK Signaling Pathway to Ameliorate Intestinal Ischemia‒Reperfusion Injury

Intestinal ischemia‒reperfusion (I/R) injury is a common pathological process in patients undergoing gastrointestinal surgery, leading to local intestinal damage and increased microvascular permeability, eventually causing extraintestinal multiple organ dysfunction or sepsis. The NLRP3-mediated inflammatory response is associated with I/R injury. Methane saline (MS) has anti-pyroptosis properties. This study aims to explore the protective effect of MS on intestinal I/R injury and its potential mechanisms. After MS pretreatment, the in vivo model was established by temporarily clipping the mouse superior mesentery artery with a noninvasive vascular clamp, and the in vitro model was established by OGD/R on Caco-2 cells. The results of HE and TUNEL staining showed intestinal barrier damage after I/R injury, which was consistent with the IHC staining results of tight junction proteins. Moreover, the expression of the NLRP3 signaling pathway was increased after I/R injury, and inhibition of NLRP3 activation reduced Caco-2 cell injury, indicating that NLRP3-mediated pyroptosis was one of the main forms of cell death after I/R injury. Subsequently, we found that MS treatment ameliorated intestinal barrier function after I/R injury by suppressing NLRP3-mediated pyroptosis. MS treatment also reduced mitochondria-associated membrane (MAM) formation, which was considered to be a platform for activation of the NLRP3 inflammasome. Importantly, MS reduced ER stress, which was related to the PERK signaling pathway. Knocking down PERK, a key protein involved in ER stress and MAM formation, reversed the protective effect of MS, indicating that MS suppressed NLRP3 by reducing ER stress and MAM formation. In conclusion, we believe that MS suppresses MAMs and activation of the NLRP3 inflammasome by regulating the PERK signaling pathway to ameliorate intestinal I/R injury.

90-OR: 3D Bioprinting of a Bionic Pancreas with a Vascular System—Results of Transplantation in Large Animals

The transplantation of the pancreas is recommended in diabetes with complications. The combination of cell biology and 3D-bioprinting can create organs with vasculature which should be functional. There are issues to be solved: leakage, thrombosis, enhancement against high pressure, connecting organ to the recipient. The purpose of this study was to demonstrate 3D-bioprinting of bionic organs with use of dECM-derived biomaterials with stable flow through the organ in vitro and in large animal studies. Materials and methods: Mathematical analysis in the designed bionic pancreas was performed. The bionic pancreas was 3D bioprinted with 2 types of bioinks. The first tests were carried out in a bioreactor then organs were subjected to magnetic resonance and X-ray with contrast. Pressure endurance tests were performed. 14 pigs received 3D-bioprinted bionic pancreas transplantation. DCL-VESS-Group (n=5) received decellularized vessels as anastomosis. 9 pigs received bionic pancreas with vascular prosthesis as anastomosis - Prosthesis-Group. Pigs were observed up to 14 days. Hist-pat analysis of removed pancreas was performed. Results: The tests carried out in the bioreactor showed the stability of the bionic organ and vascular system in MRI and X-ray examination for 5 days. No leaks beyond the bionic pancreas were observed up to 400 mmHg. In all 14 cases of transplantation there was stable flow throughout the organ after release of vascular clamp. DCL-VESS-Group - In all cases vascular cloth was observed. Prosthesis-Group - In 5 cases there were no complications influencing blood flow through the organ. 4 died to postoperative complications. Stable flow within a transplanted bionic organ was observed till 2 weeks post - surgery within ultrasound examination and radiology intervention. Histopatological showed the presence of CD31 / PECAM-1 (new blood formation). Conclusion: It is feasible to 3Dbioprint and transplant bionic organ in big animal model. Disclosure M.Wszola: Board Member; Polbionica Ltd., Stock/Shareholder; Polbionica Ltd.. K.I.Roszkowicz-ostrowska: None. L.Kownacki: None. J.Wolinski: None. A.Dobrzyn: None. A.Kaminski: None. A.Berman: Board Member; Polbionica Ltd., Stock/Shareholder; Polbionica Ltd. M.Klak: Employee; Polbionica Sp. z o.o., Stock/Shareholder; Polbionica Sp. z o.o. T.Dobrzanski: Employee; Polbionica. O.Janowska: Employee; POLBIONICA Sp. z o.o. S.Domanski: Employee; Polbionica. D.Piatek: None. J.Wejman: None. D.Szkopek: None.

Intermittent Surface Oxygenation Results in Similar Mitochondrial Protection and Maintenance of Aerobic Metabolism as Compared to Continuous Oxygenation during Hypothermic Machine Kidney Machine Perfusion.

Short bubble and subsequent surface oxygenation is an innovative oxygenation technique and alternative for membrane oxygenation during hypothermic machine perfusion (HMP). The metabolic effect of the interruption of surface oxygenation for 4 h (mimicking organ transport) during HMP was compared to continuous surface and membrane oxygenation in a pig kidney ex situ preservation model. After 30 min of warm ischemia by vascular clamping, a kidney of a ±40 kg pig was procured and subsequently preserved according to one of the following groups: (1) 22-h HMP + intermittent surface oxygenation (n = 12); (2) 22-h HMP + continuous membrane oxygenation (n = 6); and (3) 22-h HMP + continuous surface oxygenation (n = 7). Brief perfusate O2 uploading before kidney perfusion was either obtained by direct bubble (groups 1, 3) or by membrane (group 2) oxygenation. Bubble oxygenation during minimum 15 min was as efficient as membrane oxygenation in achieving supraphysiological perfusate pO2 levels before kidney perfusion. Metabolic tissue analysis (i.e., lactate, succinate, ATP, NADH, and FMN) during and at the end of the preservation period demonstrated similar mitochondrial protection between all study groups. Short bubble and subsequent intermittent surface oxygenation of the perfusate of an HMP-kidney might be an effective and cheap preservation strategy to protect mitochondria, eliminating the need/costs of a membrane oxygenator and oxygen source during transport.

(019) Complete Sub-Epithelial Vestibulectomy: Refinement of Surgery for Neuroproliferative Vestibulodynia

Abstract Introduction Complete vestibulectomy (CV) was first described by Goldstein and Marinoff, detailing an excision 3 mm cephalad to the hymen and caudad to Hart’s line. A vaginal advancement flap (VAF) to cover the defect left by excised vestibule was also described. Since neuroproliferative vestibulodynia is a field disease, The CV with VAF surgery has become widely utilized practiced by sexual medicine surgeons to treat neuroproliferative vestibulodyniaby surgeons practicing sexual medicine. However, the depth of dissection for the vestibular mucosal excision (VME) was not clearly defined. To gain a better appreciation for appropriate depth of the VME during CV with VAF, we have reviewed the results of immunohistochemical staining (IHC) of excised vestibular specimens (n=564) since 2019. In all cases, tissue depth of the excess positive CD117 and PGP9.5 staining, consistent with excess mast cells and nerves respectively, were &amp;lt; 600 μm (0.6 mm) from the epithelial surface. Objective Our objective is to describe safety and efficacy of vestibulectomy surgical technique modifications made in 2021 based on this finding. Methods We refined the CV and VAF surgery based on the observation that the IHC pathology resides very close to the vestibular epithelium. This modification has been termed complete subepithelial vestibulectomy (CSEV). These modifications keep the VME thickness as close as possible to 1-2 mm. Liposomal bupivicaine (20 ml) is injected subcutaneously throughout the vestibule to hydrodissect the mucosa. The lateral border at Hart’s line and medial border 3 mm cephalad to the hymen is incised. The mucosal surface of the vestibule is grasped with an atraumatic vascular clamp and dissected sharply with the tissue stretched over a finger to maintain a very thin VME. Excised specimens are sent for IHC staining. Patients who underwent CSEV with VAF surgery from 2021 onward were followed for ≥ 6 months. Results A total of 13 individuals (mean age 29 ± 8yrs) underwent CSEV with VAF, with a mean follow-up of 8 ± 4 months. Photomicrographs of surgical specimen confirmed the thickness to be approximately 1-2 mm (Fig 1). Blood loss was minimal, &amp;lt;100 ml in 11/13. Post-operative use of narcotics was minimal with all patients reporting less than 5 oxycodone 5mg tablets used. At 6 months post-op, 10/13 reported their vestibulodynia was much better/better based on PGI-I. Conclusions We report CSEV as a refinement of the Goldstein/Marinoff procedure. The depth of dissection and thickness of VME was 1-2 mm with this new procedure. Early results in our small case series show excellent vestibulodynia resolution and reduced pain medication requirements post-operatively. To date, the success rate of CSEV is equivalent to the outcomes from previous vestibulectomy series, ~77%, with minimal less operative blood loss. Disclosure No

A Case Report of Successful Kidney Transplantation in a Patient With Autosomal Dominant Polycystic Kidney Disease Who Underwent Thoracic Endovascular Aortic Repair for Type B Aortic Dissection

Autosomal dominant polycystic kidney disease (ADPKD) is associated with several cardiovascular disorders, including aortic dissection, which preferentially occurs at the thoracic or abdominal level. Because there are few case reports describing surgical repair for aortic dissection followed by renal transplantation in patients with ADPKD, kidney transplantation performed after repair for aortic dissection remains challenging. A 34-year-old Japanese man with end-stage renal disease secondary to ADPKD underwent thoracic endovascular aortic repair for complicated acute type B aortic dissection 12 months earlier. A contrast computed tomography scan before transplantation revealed an aortic dissection involving the descending aorta proximal to the common iliac arteries and confirmed multiple large bilateral renal cysts. After simultaneous right native nephrectomy, the patient underwent preemptive living-donor kidney transplantation obtained from his mother. Intraoperatively, we noted that dissection of the external iliac vessels was difficult because of dense adhesions. Arterial clamping was performed immediately below the bifurcation of the internal iliac artery to prevent further aortic dissection of the external iliac artery. After end-to-end anastomosis to the internal iliac artery was completed and the vascular clamp was released, the kidney began to produce urine immediately. This case suggests that kidney transplantation in patients undergoing endovascular aortic repair for aortic dissection can be performed by adequately applying a vascular clamp proximal to the internal iliac artery during vascular anastomosis.