Clamping Of Renal Vessels Research Articles

Impact of No-Clamping Partial Nephrectomy on Early Estimated Glomerular Filtration Rate Preservation.

Incidences of kidney cancers are steadily increasing. The surgical resection of renal tumors remains the treatment of choice, and different techniques provide similar oncological outcomes. Minimally invasive methods, especially partial nephrectomy (PN), have emerged as the preferred method of tumor resection, both in traditional and robot-assisted laparoscopy. PN may be performed as an open or laparoscopic operation. On-clamp PN is a variant of PN that includes the clamping of renal vessels; off-clamp PN is performed without any ischemia. Objectives: To assess the short-term loss of eGFR after on-clamp and off-clamp PN. Methods: Data from 2021 to 2024 were retrospectively collected from a hospital database. The patients included in the study had a diagnosed kidney tumor that was confirmed by MRI or CT imaging. The patients were divided into two groups depending on the type of treatment they received: on-clamp PN or off-clamp PN. Hematocrit (HCT), hemoglobin (Hb) and eGFR were measured and compared. Results: Both groups had comparable preoperative HTC, Hb, and eGFR. eGFR loss 24 h after the procedure was 35.4% lower in the off-clamp group compared to the on-clamp group (p = 0.027). Conclusions: Off-clamp PN is a safe and viable method for kidney tumor resection, both in traditional and robot-assisted laparoscopy. This technique results in a smaller perioperative loss of eGFR, which relates to better short-term functional outcomes than on-clamp PN.

Surgical and Functional Outcomes of Artery Only Versus Artery and Vein Clamping in Patients Undergoing Partial Nephrectomy: A Systematic Review and Meta-Analysis.

Clamping of renal vessels during partial nephrectomy is usually performed to improve the visualization of tumor margins. However, clamping of renal vessels has been associated with detrimental effects on renal function after surgery. This study aimed to compare artery only versus artery and vein clamping as regards the surgical and functional outcomes in patients undergoing partial nephrectomy. The literature was searched for English published studies from January 1, 2000 to August 7, 2021. The search included MEDLINE/ PubMed, Cochrane Library, Scopus, Web of Science, Google Scholar, and ProQuest, using the terms {"par- tial nephrectomy"} OR {"nephron-sparing surgery"} AND {"renal artery and vein clamping} AND {"renal artery only clamping}. Nine studies were included. Meta-analysis showed the artery only clamping grouphad a significantly less percentage of change in glomerular filtration rate at last follow-up (standardizedmean difference: -0.42 [95% CI: -0.70, -0.13], P = .004) as well as a rate of postoperative complications(odds ratio: 0.64 [95% CI: 0.41, 0.98], P = .04). However, no significant difference was observed regarding the development of chronic kidney disease. There was no significant difference regarding the warm ischemiatime, blood loss, or positive surgical margin. Artery only clamping has a comparable safety to artery and vein clamping and may produce a renoprotective effect. Due to limitations of the included studies, the conduction of large-size randomized clinical trials with a long duration of follow-up is required before recommending the replacement of artery and vein clamping with artery only clamping during partial nephrectomy.

Comparison of the Results of Therapy for cT1 Renal Carcinoma with Nephron-Sparing Surgery (NSS) vs. Percutaneous Thermal Ablation (TA).

Implementation of ultrasonography (USG), computed tomography (CT) and magnetic resonance imaging (MRI) into abdominal cavity diagnostics enabled early detection of cT1 graded renal cancers. According to European Association of Urology (EAU) and Polish urological Association (PUA) recommended method of treatment is sparing resection of renal parenchyma with tumour—nephron-sparing surgery (NSS). In selected cases other methods such as thermal ablation (TA) or cryoablation can be introduced /1/. Objectives: To evaluate the results of treatment of cT1 renal tumours with the use of NSS and TA methods. Material and methods: 140 patients with cT1 renal carcinoma were treated in 2nd Department of Urology of Medical University of Lodz between 2014 and 2017. Neuron-sparing surgery was performed in 56 cases (40%), while percutane-ous thermal ablation (TA) in 84 cases (60%). Demographic data, clinical data (lab results, Charlson index), nephrometry data (tumour size, location, R.E.N.A.L. score) post-operative data (Clavien-Dindo classifica-tion) were investigated. Histopathology results, Fuhrman malignancy grading, as total three-year survival of patients were evaluated. The following methods were used for statistical evaluation: Chi2, Fisher, W Shapiro-Wilk, U Mann-Whitney tests, Kaplan-Meier’s curve and Cox model. The results were displayed in a form of median and upper and lower quartile values (25–75%). Results: No statistical differences in gender nor left/right kidney location were observed. Patients, who underwent TA were at average 10 years older and had multiple comorbidities (median age for TA was 79, for NSS 68; median Charlson index for TA was 5 and for NSS was 3). TA patients had lesser haematological values (Hb, Ht). R.E.N.A.L. scoring demonstrated comparable nephrometry in both groups. NSS procedure was open laparotomy without temporary clamping of renal vessels. Surgical margins of resected tumours were negative. TA was performed with Cool-Tip Covidienequipment with the use of Cluster electrode and was ultraso-nography-guided. Post-treatment complications evaluated with the use of Clavien-Dindo classification were slightly more frequent for NSS method. Patients after NSS were discharged at average after 8.5 days and after TA after 3 days. Histopathological type and Fuhrman malignancy grading were comparable in both groups. TA treated patients’ death risk was 9-fold of that observed in NSS treated patients. There was 1 death for each group in perioperative period. Conclusion: 1. NSS was associated with slightly higher side effect rate but resulted in prolonged survival. 2. TA was applied to elderly patients with comorbidities. Despite less invasive treatment this group had poorer/reduced survival. 3. Charlson Comorbidity Index (CCI) and the treatment method were relevant survival factors in patients treated due to cT1 renal cancer tumours.

Intravascular volume assessment using internal jugular vein ultrasonography in pediatric renal transplant surgery: a prospective observational study

Purpose Assessment of the intravascular volume status during surgery is challenging, especially in pediatric patients. Ultrasound has become a versatile noninvasive modality for assessing volume status. This study aimed to evaluate the reliability of ultrasonographic internal jugular vein (IJV) dimensions as a new tool to assess the intravascular volume status in pediatric patients undergoing living donor renal transplant surgery. Patients and methods This prospective observational study included pediatric renal transplant recipients, aged 3–12 years, weighing more than 10 kg, and having an end-stage renal disease. Hemodynamic data (heart rate, systolic, diastolic, and mean blood pressures), central venous pressure (CVP), sonographic measurement of IJV (diameter and cross-sectional area), and left ventricular end-diastolic area (LVEDA) were measured 1 min after induction, before clamping of renal vessels, and after declamping of renal vessels. The correlations between the ultrasonographic IJV dimensions and both LVEDA (primary outcome) and CVP were evaluated. Results Overall, 18 pediatric patients (12 females, six males) with end-stage renal disease were eligible for this study. The mean age was 9.33±2.57 years, and the mean weight was 21.67±5.99 kg. There was a poor correlation between IJV dimensions (diameter and cross-sectional area) and both LVEDA and CVP at the three-time points of assessments. Conclusion Ultrasonographic IJV dimensions (diameter and cross-sectional area) were not reliable for assessing intravascular volume status in living donor renal transplant surgery in pediatric patients.

Acute Kidney Ischemic Injury in a Rat Model Treated by Human Omental Mesenchymal Stem Cells

BackgroundMesenchymal stem cells (MSCs) may provide a novel clinical approach for acute kidney injury (AKI), which represents a severe health care condition. The human omentum is an important source of MSCs. We investigated the effects of human omental mesenchymal stem cells (HO-MSCs) after induction of ischemic AKI in a rat model. MethodsThe ischemic-reperfusion injury (IRI) was induced at reperfusion following a 45-minute clamping of renal vessels. Twenty animals were used in this study. Each rat was randomly assigned to 1 of 2 groups: G1 (control, n = 10; IRI infusion of phosphate buffer solution) or G2 (HO-MSCs, n = 10; IRI infusion of HO-MSCs). The infusions were performed in the parenchyma at reperfusion. Renal function at 1, 3, 5, and 7 days was assessed. At sacrifice, histologic samples were analyzed by light, and renal injury was graded. ResultsHO-MSCs induced an accelerated renal exocrine functional recovery, demonstrated by biochemical parameters and confirmed by histology showing that histopathological alterations associated with ischemic injury were less severe in cell-treated kidneys as compared with control groups (P < .05). The renal damage degree was significantly less in the animals of the HO-MSC group (P < .0001). ConclusionsThese results suggest that HO-MSCs could be useful in the treatment of AKI in a rat model with possible potential implication in clinical setting.

Study of Acute Kidney Injury in hyperandrogenemic female rats

Chronic hyperandrogenemia is hallmark of polycystic ovarian syndrome (PCOS), affecting ~10% of women of reproductive age. Compared to men, women are protected against ischemia‐ reperfusion (I/R) acute kidney injury (AKI), but the potential susceptibility of women that have elevated androgens, as women with PCOS, to develop I/R‐induced AKI is not clear. Other models of hyperandrogenemia in females in which I/R AKI was studied utilized levels of testosterone similar to males. Using an established female rat model of PCOS that has a 3 fold increase in DHT, such as women with PCOS and 10 fold lower than in males, we tested the hypothesis that chronic hyperandrogenemia increases the risk of I/R‐induced AKI compare to placebo controls. Female SD rats were implanted with dihydrotestosterone (DHT, 7.5mg/90d) or placebo pellets (n=11/grp) beginning at 6 wks of age; pellets were changed every 85 d. At 6–7 mos of age, rats (n=3–4/grp) were subjected to sham or renal I/R with bilateral clamping of renal vessels for 30 min at 37±0.5°C. Rats were placed in metabolism cages for 24hrs reperfusion. At 48–72hr post‐surgery rats were again put in metabolic cages for 24hr, and then euthanized for blood and tissue samples. I/R increased plasma creatinine (PCr) 24hr post reperfusion in placebo (2.58±0.34 vs 0.86±0.1 mg/dL, p&lt;0.05) as well as DHT treated rats (4.53± 0.46 vs 0.9±0.06 mg/dL, P&lt;0.001) compared to sham‐I/R group. As noted, PCr in DHT‐treated rats was significantly higher than in placebo rats (4.53± 0.46 vs 2.58±0.34 mg/dL, p&lt;0.05). When DHT rats were pre‐treated with androgen receptor antagonist (Flutamide, 30mg/kg/day, s.c.) for three days prior to I/R, PCr levels 24hr post reperfusion were not different than DHT–treated I/R groups (4.75 0.52 vs 4.53± 0.46 mg/dL, p=ns). These data show that rat exposure to chronic hyperandrogenemia causes significantly greater renal injury in response to I/R AKI than in controls. This injury is independent of the androgen receptor suggesting other mechanisms may be contributing to the higher level of renal injury after I/R AKI in females with PCOS.Support or Funding InformationSupported by NIH R01HL66072, P01HL05971.

NEW METHOD OF PARTIAL NEPHRECTOMY WITH SELECTIVE PARENCHYMA CLAMPING

The authors suggested a new method of performance of open, laparoscopic and robot-assisted partial nephrectomy using specially developed instruments for selective parenchyma clamping in order to improve the functional results of renal cell carcinoma treatment. The operation with clamping of renal vessels was carried out in 86 cases and clamping of renal parenchyma was used in 24 cases. It was shown, that the open, laparoscopic and robot-assisted partial nephrectomy could be safely performed in conditions of selective ischemia of the renal parenchyma without clamping of renal vessels.

Abstract 301: Testosterone propionate in Ischemia-reperfusion (I/R) induced Acute Kidney Injury (AKI)

Acute kidney injury (AKI) is a leading cause of morbidity and mortality, and men are more prone to AKI than women implicating androgens as a causative factor whereas estrogens have been thought to be protective. These effects are independent of both androgen and estrogen receptors. We showed recently that infusion of testosterone 3 hrs post reperfusion protected rats from renal injury following ischemia/reperfusion (I/R). In the present study, we tested the hypothesis that testosterone works as a renal vasodilator perhaps by increasing nitric oxide. Male SD rats (8-14 wks; n=3-5/grp) were subjected to sham surgery or I/R induced AKI with bilateral clamping of renal vessels for 30 min. Three hrs after reperfusion, rats were given testosterone propionate (20 μg/kg iv over 10 min) or vehicle (0.75%EtOH). Rats were placed in metabolism cages for 24hrs for nitrate/nitrite excretion (UNOxV), and euthanized and blood taken for creatinine (PCr). I/R increased PCr and decreased UNOxV, compared to shams (0.58±0.05 vs. 3.99±0.36 mg/dL, p&lt;0.0001; UNOxV: 8.54±1.7 vs 1.7±0.78 μmol/day/kg BW, p&lt;0.001). Testosterone attenuated the increase in PCr (2.03±0.23 mg/dL, p&lt; 0.01) but had no effect on UNOxV (3.79±0.91 μmol/day/kg). Pretreatment of rats with L-NAME (1mg/kg/day; dose that did not increase BP) for 48 hours prior to I/R abolished the improvement in PCr with testosterone (PCr: 3.73±0.82 mg/dL, p&lt;0.05 vs no LNAME). Infusion of renal vasodilator PGE2 (30μg/kg iv over 10 min 3 hrs after reperfusion) attenuated PCr compared to I/R alone (2.95±0.21mg/dL, p&lt;0.01) but was independent of increased NO (2.61±0.63 μmol/day/kg, p=NS vs I/R alone), and was not as effective in reducing PCr as testosterone (p&lt;0.05). These data show that low dose testosterone infusion 3 hrs post reperfusion improves renal function in AKI perhaps by causing renal vasodilation. When NO synthesis is blocked, testosterone is incapable of improving PCr after I/R. Furthermore, although the known renal vasodilator PGE2 also improves PCr in I/R, although not as effectively as testosterone. These data continue to support the notion that testosterone infusion has therapeutic potential for the treatment of I/R induced AKI in humans. Supported by NIH R01HL66072, P01HL05971 and AHA 14POST18640015.

Laser-supported partial laparoscopic nephrectomy for renal cell carcinoma without ischaemia time

BackgroundTo date, elective nephron-sparing surgery is an established method for the exstirpation of renal tumors. While open partial nephrectomy remains the reference standard of the management of renal masses, laparoscopic partial nephrectomy (LPN) continues to evolve. Conventional techniques include clamping the renal vessels risking ischaemic damage of the clamped organ. Thus, new techniques are needed that combine a sufficient tissue incision for exstirpation of the tumor with an efficient coagulation to assure haemostasis and abandon renal vessel clamping in LPN. Laser-excision of renal tumors during laparoscopic surgery seems to be a logical solution.MethodsWe performed nephron-sparing surgery without clamping of the renal vessels in 11 patients with a renal tumor in exophytic position (mean size 32 mm, ranging 8–45 mm) by laser-supported LPN.ResultsRegular ultrasound monitoring and insertion of a temporary drainage showed no evidence of postoperative hemorrhage. All tumors were removed with a histopathologically confirmed surrounding margin of normal renal tissue (R0 resection). Serum creatinine, hemoglobin, and hematocrit were nearly unaltered before and after surgery.ConclusionsThe experience won in these patients have confirmed that laser-assisted LPN without clamping of the renal vessels could be a safe and gentle alternative to classic partial nephrectomy in patients with exophytic position of renal tumors.

Abstract 655: Ischemia-induced Epoxyeicosatrienoic Acid Release Protects Female Rats From Acute Kidney Injury

Females are naturally protected against ischemia/reperfusion (I/R)-induced acute kidney injury (AKI) in various clinical and experimental settings. However, the underlying mechanisms are unknown. We hypothesized that female protection may be conferred by enhanced production of cytochrome P450 (CYP)-dependent epoxyeicosatrienoic acids (EETs) that promote vasodilation as well as antiinflammatory and antiapoptotic pathways in the kidney. To test this hypothesis, we first analyzed the renal CYP-eicosanoid profile by liquid chromatography tandem mass spectrometry in male and female Lewis rats. Ischemia was induced through 45 min of left renal vessel clamping after right nephrectomy (n=6-8 per group). In non-ischemic controls, male and female kidneys stored almost identical amounts of EETs as well as 20-hydroxyeicosatetraenoic acid (20-HETE), both predominantly esterified into phospholipids, under basal non-ischemic conditions. 45 min of ischemia induced a massive release of EETs from membrane stores in females but not males. The free renal EET-levels reached 70.2±20.1 in females compared to only 4.6±1.3 ng/g in males. After ischemia, the ratio of free EETs to free 20-HETE was about 1:1 in females and 1:3 in males. Next, we proved the functional importance of EETs in renal protection by pretreating males with a synthetic EET-agonist (12-HUDE) and females with a selective EET-antagonist (14,15-EEZE-mSI). As analyzed two days after reperfusion, the EET-agonist protected males against loss of creatinine clearance (1.03±0.18 vs. 0.26±0.02 ml/min, p&lt;0.01 vs. vehicle, compared to 1.28±0.06 ml/min in sham control). Females were rendered susceptible to I/R-injury by the EET-antagonist (creatinine clearance: 0.25±0.05 vs. 0.67±0.04; p&lt;0.01 vs. vehicle, compared to 0.81±0.04 ml/min in sham control). Changes in inflammatory cell infiltration and tubular apoptosis paralleled these effects on renal function. Our results indicate that female rats are protected against renal I/R-injury by enhanced ischemia-induced EET-release and demonstrate that renal protection can be transferred to males using synthetic EET-agonists.

Laser nun auch in der organerhaltenden Nierenchirurgie?

Kidney surgery is subject to continuous change. Partial nephrectomy is the prevailing method for small and medium-sized tumours and proven to be superior to radical nephrectomy. The conventional technique usually includes clamping the renal vessels. The duration of the ischaemia caused determines the outcome of the remaining renal function. The shorter the ischaemic time the more likely the renal function will be preserved. Thus, new techniques are needed to abandon renal vessel clamping. Essential is a combination of good cutting abilities and assured haemostasis. To date, the commonly used techniques for cutting in partial nephrectomy only partially fulfil these requirements. Establishment of laser in urology offers a new surgical technique that combines both. In spite of the still limited data on laser use in kidney surgery, this method can be assessed favourably. Laser offers a possibility of both open and laparoscopic partial nephrectomy avoiding renal vessel clamping without additional risks or complications.

Histological analysis and the blood flux in kidneys submitted to different periods of ischemia/reperfusion

Evaluate the renal blood flow by using a laser flow meter, Laserflow Vasamedics®, after the ischemia/reperfusion in two different times of the arterial renal vessel clamping. The renal blood flow was evaluated by using a laser flow meter after two different times of ischemia/reperfusion procedure, 30 and 60 minutes. It was used 20 Wistar male rats, divided in two groups of 10 rats: Group A (30 minutes of ischemia on the left kidney, with later analysis of the blood flow in 1, 5 and 20, after the renal reperfusion start) and Group B (60 minutes of ischemia on the left kidney, with later analysis of the blood flow in 1, 5 and 20 minutes, after the renal reperfusion start). In the first minute, there were not significant differences between the two groups (p=0.789). In the 5th minute there were not significant differences also, but there was a tendency (p=0.068). In the 20th minute, there was a significant difference between the 2 groups (p=0.022). When the means are observed, it is possible to notice that Group A has a larger flux than Group B. The kidneys submitted to 30' of ischemia/reperfusion are subject to a larger restitution of the blood flow in comparison to the Group which had a longer time.

Comparison of Clamping Modalities in a Rabbit Model of Normothermic Renal Ischemia

The objective of this study was to investigate the patterns of renal function recovery with different renal vessel clamping modalities during a prolonged warm ischemia (WI) condition in an experimental two-kidney rabbit model. Twenty-eight rabbits were randomly clustered into four groups and underwent laparotomy with different types of renal pedicle clamping. Group 1 (n=4) was sham-operated. Group 2 (n=8) underwent 80 minutes of WI with artery only clamping. Group 3 (n=8) underwent arteriovenous clamping for 80 minutes, and group 4 (n=8) received an arteriovenous clamping for 80 minutes with 10-second declamping periods every 20 minutes. Serum levels of creatinine (SCr) were recorded preoperatively and on postoperative days (PODs) 1, 3, and 7. Renal function was evaluated by (99m)technetium-mercaptoacetyltriglycine scintigraphy. Afterward, the animals were euthanized, and the kidneys were harvested and evaluated microscopically. Renal function completely recuperated on POD 7 in the groups that underwent artery only and ateriovenous intermittent clamping, and both of these methods were superior to ateriovenous clamping (P<0.001). SCr showed a similar variation in all the clamping groups and did not demonstrate statistical differences among the groups. Histopathologic changes were similar among the ischemic groups. The less deleterious clamping modalities in this experimental model were the artery only and intermittent en bloc clamping methods.

Kidney Healing After Laparoscopic Partial Nephrectomy Without Collecting System Closure in Pigs

To access the kidney healing after laparoscopic partial nephrectomy without closing of the collecting system in pigs. Fourteen pigs underwent left partial laparoscopic nephrectomy, with removal of 25% of the kidney length at caudal pole (n = 7) or at cranial pole (n = 7). Briefly, the surgical technique involved a transperitoneal laparoscopic access, en bloc vascular clamping of renal vessels, tissue excision with cold scissor and monopolar energy hemostasis of only the parenchyma, leaving the collecting system opened, with no insertion of a double-J catheter. The animals were clinically evaluated during 14 days, and afterward were killed. Serum levels of urea and creatinine were assessed prior and at different moments after surgery. Macroscopic necropsy analysis, a retrograde ex vivo pyelogram and a histologic study of the operated renal poles were performed. The animals did not show any postoperative clinical alterations. Serum levels of urea and creatinine showed a slight raising at the second postoperative day with gradual decreasing to preoperative levels. At necropsy, the abdominal cavity was normal, with normal quantity and aspect of peritoneal liquid. No signs of urine leakage were found. The operated renal pole was always involved by a perirenal fibrosis with adherences to adjacent organs. The pig kidney collecting system healed well without any kind of suture or internal drainage. Therefore, we concluded that the pig kidney is not an adequate model for research on which the collecting system healing is an important aspect to be considered.

Kidney Deformation and Intraprocedural Registration: A Study of Elements of Image-Guided Kidney Surgery

Central to any image-guided surgical procedure is the alignment of image and physical coordinate spaces, or registration. We explored the task of registration in the kidney through in vivo and ex vivo porcine animal models and a human study of minimally invasive kidney surgery. A set of (n = 6) ex vivo porcine kidney models was utilized to study the effect of perfusion and loss of turgor caused by incision. Computed tomography (CT) and laser range scanner localizations of the porcine kidneys were performed before and after renal vessel clamping and after capsular incision. The da Vinci robotic surgery system was used for kidney surface acquisition and registration during robot-assisted laparoscopic partial nephrectomy. The surgeon acquired the physical surface data points with a tracked robotic instrument. These data points were aligned to preoperative CT for surface-based registrations. In addition, two biomechanical elastic computer models (isotropic and anisotropic) were constructed to simulate deformations in one of the kidneys to assess predictive capabilities. The mean displacement at the surface fiducials (glass beads) in six porcine kidneys was 4.4 ± 2.1 mm (range 3.4-6.7 mm), with a maximum displacement range of 6.1 to 11.2 mm. Surface-based registrations using the da Vinci robotic instrument in robot-assisted laparoscopic partial nephrectomy yielded mean and standard deviation closest point distances of 1.4 and 1.1 mm. With respect to computer model predictive capability, the target registration error was on average 6.7 mm without using the model and 3.2 mm with using the model. The maximum target error reduced from 11.4 to 6.2 mm. The anisotropic biomechanical model yielded better performance but was not statistically better. An initial point-based alignment followed by an iterative closest point registration is a feasible method of registering preoperative image (CT) space to intraoperative physical (robot) space. Although rigid registration provides utility for image-guidance, local deformations in regions of resection may be more significant. Computer models may be useful for prediction of such deformations, but more investigation is needed to establish the necessity of such compensation.

Reply

We appreciate the reviewer's comments. Presently, laparoscopic partial nephrectomy is considered a key treatment measure for small renal mass cases. Particularly in cases of a large-sized mass or those in which a mass was placed in the location where resection could not be easily performed, surgery after the clamping of renal vessels is considered crucial to reduce the bleeding or to more easily confirm the tumor resection margin. From this aspect, the current initial clinical report in pediatric urology describes a LESS partial nephrectomy after the clamping of renal vessels.

Editorial Comment

The authors are to be commended on exploring the merits of the LESS platform for partial nephrectomy in a child. Although they demonstrate the feasibility and safety of this approach, as well as the benefit of improved cosmesis and reduced analgesic requirement, which has been reported by other investigators in pediatric patients, 1 Kaouk J.H. Palmer J.S. Single-port laparoscopic surgery: initial experience in children for varicocelectomy. BJU Int. 2008; 102: 97-99 Crossref PubMed Scopus (178) Google Scholar , 2 Park Y.H. Kang M.Y. Jeong M.S. Choi H. Kim H.H. Laparoendoscopic single-site nephrectomy using a homemade single-port device for single-system ectopic ureter in a child: initial case report. J Endourol. 2009; 23: 833-835 Crossref PubMed Scopus (69) Google Scholar , 3 Bayazit Y. Aridogan I.A. Abat D. Satar N. Doran S. Pediatric transumbilical laparoendoscopic single-site nephroureterectomy: initial report. Urology. 2009; 74: 1116-1119 Abstract Full Text Full Text PDF PubMed Scopus (39) Google Scholar they acknowledge some of the key drawbacks that have been encountered and commented upon by other pioneers in this field (e.g., longer warm ischemia time, difficulty suturing, instrument clashing). 4 Aron M. Canes D. Desai M.M. Haber G.P. Kaouk J.H. Gill I.S. Transumbilical single-port laparoscopic partial nephrectomy. BJU Int. 2009; 103: 516-521 Crossref PubMed Scopus (145) Google Scholar Although this report is limited by its lack of long-term follow up, it adds to a growing body of exciting literature on the feasibility of increasingly complex minimally invasive procedures using various LESS platforms. Nonetheless, pediatric LESS partial nephrectomy is a procedure whose limitations are a direct consequence of the limited experience and evolving enabling technology. As such, its performance and evaluation should be carried out by experienced minimally invasive/pediatric urological surgeons. Ideally, a prospective multicenter comparison with multiport laparoscopy should be performed in the pediatric population to determine whether there is any substantive advantage for the LESS platform. Pediatric Laparoendoscopic Single-site Partial Nephrectomy: Initial ReportUrologyVol. 76Issue 1PreviewWe present a case of transumbilical laparoendoscopic single-site surgery (LESS) for partial nephrectomy in a child. Full-Text PDF ReplyUrologyVol. 76Issue 1PreviewWe appreciate the reviewer's comments. Presently, laparoscopic partial nephrectomy is considered a key treatment measure for small renal mass cases. Particularly in cases of a large-sized mass or those in which a mass was placed in the location where resection could not be easily performed, surgery after the clamping of renal vessels is considered crucial to reduce the bleeding or to more easily confirm the tumor resection margin. From this aspect, the current initial clinical report in pediatric urology describes a LESS partial nephrectomy after the clamping of renal vessels. Full-Text PDF

Changes in Pituitary Adenylate Cyclase-Activating Polypeptide Following Renal Ischemia-Reperfusion in Rats

PACAP (pituitary adenylate cyclase-activating polypeptide) occurs in two biologically active forms, with 38 and 37 amino acid residues (PACAP38 and PACAP27). In mammalian tissues, PACAP38 is the dominant form. Diverse effects have been described in the cardiovascular, respiratory, gastrointestinal, and urogenital systems. PACAP is known for its strong cytoprotective effects, which are present endogenously as well, as proven by knockout studies and results showing that PACAP is up-regulated following diverse injuries. Little is known about such effects in the kidney. We have previously shown that PACAP is protective in renal ischemia-reperfusion injury. Therefore, the aim of the present study was to investigate the changes of endogenous PACAP following 60-minute renal ischemia using radioimmunoassay. Changes were observed within 24 hours following renal vessel clamping. In the cortex, an acute decrease was followed by an increase on the intact side, and levels returned to original ones on the operated side. In the medulla, changes were only observed on the clamped side: a marked up-regulation was detected in PACAP38-like immunoreactivity within the first 24 hours. The present study showed that PACAP38- and PACAP27-like immunoreactivities sensitively react to renal ischemia-reperfusion, the physiological importance of which awaits further investigation.

The Impact of Timing of Maximal Crystalloid Hydration on Early Graft Function During Kidney Transplantation

Early graft function is crucial for successful kidney transplantation. Maintaining adequate hydration is complicated by rapid movement of water to the extravascular space. We designed this study to test the effect of maximal hydration during graft ischemia time on early renal function. Forty adult patients with chronic renal failure underwent renal transplantation from related living donors. Study subjects were randomly assigned 1 of 2 regimens for intraoperative hydration. The constant infusion rate group received normal saline 0.9% at an infusion rate 10 to 12 mL . kg(-1) . h(-1) from the start of surgery until the renal vessels were unclamped after vascular anastomosis. The central venous pressure target (CVPT) group received normal saline 0.9% titrated to maintain a specific central venous pressure (CVP). The target CVP from the start of surgery until clamping of the donor renal vessels was 5 mm Hg except for the interval from clamping of the renal vessels until the end of renal vascular anastomosis, when the target CVP was 15 mm Hg. Perioperative hemodynamics, infused saline volumes, rate of infusion, onset of diuresis, graft turgidity, urine volume, and renal function during the first 5 postoperative days were recorded. At the end of renal ischemia time, both groups had received approximately 3 L crystalloid solution. The CVPT group achieved the highest peak of intravascular volume expansion with an average infusion rate of 48.3 mL . min(-1) during 48 +/- 12 minutes of renal ischemia. The CVPT group had better graft function, required fewer vasopressors and diuretics, and had less postoperative tissue edema than the constant infusion rate group. Hydration directed toward maintaining a given CVP during kidney transplantation produced a more stable hemodynamic profile and promoted diuresis. The calculated infusion rate of approximately 45 to 50 mL . min(-1), within an hour ischemia time, seems feasible to enhance early graft function. A larger trial with long-term follow-up of renal function is warranted to confirm the clinical benefit of titrating IV crystalloid administration to maintain a given CVP in this population.

818 CHRONIC KIDNEY DISEASE PRIOR AND FOLLOWING NEPHRON-SPARING SURGERY

You have accessJournal of UrologyKidney Cancer: Localized I1 Apr 2010818 CHRONIC KIDNEY DISEASE PRIOR AND FOLLOWING NEPHRON-SPARING SURGERY Melanie Clark, Sergey Shikanov, Jay Raman, Benjamin Smith, Matthew Kaag, Paul Russo, Jeffrey C. Wheat, J. Stuart Wolf, Surena Matin, William Huang, Arieh Shalhav, and Scott E. Eggener Melanie ClarkMelanie Clark Chicago, IL More articles by this author , Sergey ShikanovSergey Shikanov Chicago, IL More articles by this author , Jay RamanJay Raman Hershey, PA More articles by this author , Benjamin SmithBenjamin Smith Hershey, PA More articles by this author , Matthew KaagMatthew Kaag Hershey, PA More articles by this author , Paul RussoPaul Russo New York, NY More articles by this author , Jeffrey C. WheatJeffrey C. Wheat Ann Arbor, MI More articles by this author , J. Stuart WolfJ. Stuart Wolf Ann Arbor, MI More articles by this author , Surena MatinSurena Matin Houston, TX More articles by this author , William HuangWilliam Huang New York, NY More articles by this author , Arieh ShalhavArieh Shalhav Chicago, IL More articles by this author , and Scott E. EggenerScott E. Eggener Chicago, IL More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2010.02.1519AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES We performed a multi-institutional retrospective cohort study to evaluate baseline renal function of patients who underwent partial nephrectomy for renal tumors and determine rates of progression to higher stages of chronic kidney disease (CKD). METHODS Preoperative and postoperative serum creatinine values were obtained from patients who underwent partial nephrectomy at six institutions with a normal contralateral kidney and had baseline CKD of I (GFR > 90 ml/min/1.73m2), II (GFR = 60 – 89 ml/min/1.73m2), or III (GFR = 30 – 59 ml/min/1.73m2). Patients with baseline CKD IV and V were excluded. The Modification of Diet in Renal Disease Study (MDRD) equation was used to estimate glomerular filtration rate (GFR) and determine CKD stage. The endpoint was change in CKD at long-term follow-up (3–18 months). A multivariate logistic regression model tested the association of newly acquired CKD III with age, sex, race, BMI, surgical approach, hypertension, diabetes, coronary artery disease, tumor size and margins, renal vessel clamping, ischemia time, hypothermia, and estimated blood loss. RESULTS A total of 1,228 patients underwent partial nephrectomy with follow-up creatinine data at least 3 months following surgery. Mean baseline GFR was 75 ml/min/1.73m2. At baseline, 19% of patients had CKD I, 59% had CKD II, and 22% had CKD III. At long-term follow-up, mean post-operative GFR for patients with baseline CKD I or II was 71 ml/min/1.73m2 with 280 (29%) patients newly entering CKD III. Increasing age (OR = 1.05, p <0.001), female gender (OR = 1.80 p = 0.002), increasing tumor size (OR = 1.20, p = 0.003), clamping the renal artery and vein (B = 2.28, p = 0.054), and lower pre-operative GFR (OR = 1.05, p <0.001) were independently associated with newly acquired CKD III. The presence of co-morbid conditions did not independently predict increased risk of a higher CKD stage. CONCLUSIONS Approximately one-quarter of patients presenting for partial nephrectomy with a normal contralateral kidney have stage III CKD and an additional 29% will develop CKD III or higher following surgery. Increasing age, female gender, larger tumor size, clamping the artery and vein, and lower baseline GFR are associated with worsening kidney function following surgery. © 2010 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 183Issue 4SApril 2010Page: e320 Advertisement Copyright & Permissions© 2010 by American Urological Association Education and Research, Inc.MetricsAuthor Information Melanie Clark Chicago, IL More articles by this author Sergey Shikanov Chicago, IL More articles by this author Jay Raman Hershey, PA More articles by this author Benjamin Smith Hershey, PA More articles by this author Matthew Kaag Hershey, PA More articles by this author Paul Russo New York, NY More articles by this author Jeffrey C. Wheat Ann Arbor, MI More articles by this author J. Stuart Wolf Ann Arbor, MI More articles by this author Surena Matin Houston, TX More articles by this author William Huang New York, NY More articles by this author Arieh Shalhav Chicago, IL More articles by this author Scott E. Eggener Chicago, IL More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...