Intrarenal pressure with hand-pump or pressurized-bag irrigation: randomized clinical trial at retrograde intrarenal surgery.

BACKGROUND: The aim was to ascertain the impact of irrigation technique on human intrarenal pressure during retrograde intrarenal surgery. METHODS: A parallel randomized trial recruited patients across three hospital sites. Patients undergoing retrograde intrarenal surgery for renal stone treatment with an 11/13-Fr ureteral access sheath were allocated randomly to 100 mmHg pressurized-bag (PB) or manual hand-pump (HP) irrigation. The primary outcome was mean procedural intrarenal pressure. Secondary outcomes included maximum intrarenal pressure, variance, visualization, HP force of usage, procedure duration, stone clearance, and clinical outcomes. Live intrarenal pressure monitoring was performed using a COMETTMII pressure guidewire, deployed cystoscopically to the renal pelvis. The operating team was blinded to the intrarenal pressure. RESULTS: Thirty-eight patients were randomized between July and November 2023 (trial closure). The final analysis included 34 patients (PB 16; HP 18). Compared with PB irrigation, HP irrigation resulted in significantly higher mean intrarenal pressure (mean(s.d.) 62.29(27.45) versus 38.16(16.84) mmHg; 95% c.i. for difference in means (MD) 7.97 to 40.29 mmHg; P = 0.005) and maximum intrarenal pressure (192.71(106.23) versus 68.04(24.16) mmHg; 95% c.i. for MD 70.76 to 178.59 mmHg; P < 0.001), along with greater variance in intrarenal pressure (log transformed) (6.23(1.59) versus 4.60(1.30); 95% c.i. for MD 0.62 to 2.66; P = 0.001). Surgeon satisfaction with procedural vision reported on a scale of 10 was higher with PB compared with HP irrigation (mean(s.d.) 8.75(0.58) versus 6.28(1.27); 95% c.i. for MD 1.79 to 3.16; P < 0.001). Subjective HP usage force did not correlate significantly with transmitted intrarenal pressure (Pearson R = -0.15, P = 0.57). One patient (HP arm) developed urosepsis. CONCLUSION: Manual HP irrigation resulted in higher and more fluctuant intrarenal pressure trace (with inferior visual clarity) than 100-mmHg PB irrigation. REGISTRATION NUMBER: osf.io/jmg2h (https://osf.io/).

Design and utilisation of a novel, high-fidelity, low-cost, hybrid-tissue simulation model to facilitate training in robot-assisted partial nephrectomy.

Robot-assisted partial nephrectomy (RAPN) has rapidly evolved as the standard of care for appropriately selected renal tumours, offering key patient benefits over radical nephrectomy or open surgical approaches. Accordingly, RAPN is a key competency that urology trainees wishing to treat kidney cancer must master. Training in robotic surgery is subject to numerous challenges, and simulation has been established as valuable step in the robotic learning curve. However, simulation models are often both expensive and suboptimal in fidelity. This means that the number of practice repetitions for a trainee may limited by cost restraints, and that trainees may struggle to reconcile the skills obtained in the simulation laboratory with real-world practice in the operating room. We have developed a high-fidelity, low-cost, customizable model for RAPN simulation based on porcine tissue. The model has been utilised in teaching courses at our institution, confirming both feasibility of use and high user acceptability. We share the design of our model in this proof-of-concept report.

In vivo ureteroscopic intrarenal pressures and clinical outcomes: a multi-institutional analysis of 120 consecutive patients.

OBJECTIVES: To evaluate the pressure range generated in the human renal collecting system during ureteroscopy (URS), in a large patient sample, and to investigate a relationship between intrarenal pressure (IRP) and outcome. PATIENTS AND METHODS: A prospective multi-institutional study was conducted, with ethics board approval; February 2022-March 2023. Recruitment was of 120 consecutive consenting adult patients undergoing semi-rigid URS and/or flexible ureterorenoscopy (FURS) for urolithiasis or diagnostic purposes. Retrograde, fluoroscopy-guided insertion of a 0.036-cm (0.014″) pressure guidewire (COMET™ II, Boston Scientific, Marlborough, MA, USA) to the renal pelvis was performed. Baseline and continuous ureteroscopic IRP was recorded, alongside relevant operative variables. A 30-day follow-up was completed. Descriptive statistics were applied to IRP traces, with mean (sd) and maximum values and variance reported. Relationships between IRP and technical variables, and IRP and clinical outcome were interrogated using the chi-square test and independent samples t-test. RESULTS: A total of 430 pressure traces were analysed from 120 patient episodes. The mean (sd) baseline IRP was 16.45 (5.99) mmHg and the intraoperative IRP varied by technique. The mean (sd) IRP during semi-rigid URS with gravity irrigation was 34.93 (11.66) mmHg. FURS resulted in variable IRP values: from a mean (sd) of 26.78 (5.84) mmHg (gravity irrigation; 12/14-F ureteric access sheath [UAS]) to 87.27 (66.85) mmHg (200 mmHg pressurised-bag irrigation; 11/13-F UAS). The highest single pressure peak was 334.2 mmHg, during retrograde pyelography. Six patients (5%) developed postoperative urosepsis; these patients had significantly higher IRPs during FURS (mean [sd] 81.7 [49.52] mmHg) than controls (38.53 [22.6] mmHg; P < 0.001). CONCLUSIONS: A dynamic IRP profile is observed during human in vivo URS, with IRP frequently exceeding expected thresholds. A relationship appears to exist between elevated IRP and postoperative urosepsis.

Perceptions and Practice Patterns of Urologists Relating to Intrarenal Pressure During Ureteroscopy: Findings from a Global Cross-Sectional Analysis.

Objectives: To explore beliefs and practice patterns of urologists regarding intrarenal pressure (IRP) during ureteroscopy (URS). Methods: A customized questionnaire was designed in a 4-step iterative process incorporating a systematic review of the literature and critical analysis of topics/questions by six endourologists. The 19-item questionnaire interrogated perceptions, practice patterns, and key areas of uncertainty regarding ureteroscopic IRP, and was disseminated via urologic societies, networks, and social media to the international urologic community. Consultants/attendings and trainees currently practicing urology were eligible to respond. Quantitative responses were compiled and analyzed using descriptive statistics and chi-square test, with subgroup analysis by procedure volume. Results: Responses were received from 522 urologists, practicing in six continents. The individual question response rate was >97%. Most (83.9%, 437/515) respondents were practicing at a consultant/attending level. An endourology fellowship incorporating stone management had been completed by 59.2% (307/519). The vast majority of respondents (85.4%, 446/520) scored the perceived clinical significance of IRP during URS ≥7/10 on a Likert scale. Concern was uniformly reported, with no difference between respondents with and without a high annual case volume (p = 0.16). Potential adverse outcomes respondents associated with elevated ureteroscopic IRP were urosepsis (96.2%, 501/520), collecting system rupture (80.8%, 421/520), postoperative pain (67%, 349/520), bleeding (63.72%, 332/520), and long-term renal damage (26.1%, 136/520). Almost all participants (96.2%, 501/520) used measures aiming to reduce IRP during URS. Regarding the perceived maximum acceptable threshold for mean IRP during URS, 30 mm Hg (40 cm H2O) was most frequently selected [23.2% (119/463)], with most participants (78.2%, 341/463) choosing a value ≤40 mm Hg. Conclusions: This is the first large-scale analysis of urologists' perceptions of ureteroscopic IRP. It identifies high levels of concern among the global urologic community, with almost unanimous agreement that elevated IRP is associated with adverse clinical outcomes. Equipoise remains regarding appropriate IRP limits intraoperatively and the most appropriate technical strategies to ensure adherence to these.

Comparing the outcomes of open, laparoscopic and robot-assisted partial nephrectomy: a network meta-analysis.

OBJECTIVE: To perform a systematic review and network meta-analysis (NMA) to determine the advantages and disadvantages of open (OPN), laparoscopic (LPN), and robot-assisted partial nephrectomy (RAPN) with particular attention to intraoperative, immediate postoperative, as well as longer-term functional and oncological outcomes. METHODS: A systematic review was performed as per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses-NMA guidelines. Binary data were compared using odds ratios (ORs). Mean differences (MDs) were used for continuous variables. ORs and MDs were extracted from the articles to compare the efficacy of the various surgical approaches. Statistical validity is guaranteed when the 95% credible interval does not include 1. RESULTS: In total, there were 31 studies included in the NMA with a combined 7869 patients. Of these, 33.7% (2651/7869) underwent OPN, 20.8% (1636/7869) LPN, and 45.5% (3582/7689) RAPN. There was no difference for either LPN or RAPN as compared to OPN in ischaemia time, intraoperative complications, positive surgical margins, operative time or trifecta rate. The estimated blood loss (EBL), postoperative complications and length of stay were all significantly reduced in RAPN when compared with OPN. The outcomes of RAPN and LPN were largely similar except the significantly reduced EBL in RAPN. CONCLUSION: This systematic review and NMA suggests that RAPN is the preferable operative approach for patients undergoing surgery for lower-staged RCC.

Ipsilateral robot assisted laparoscopic side to side ureteroureterostomy in a duplex collecting system - A video case report with 1 year follow up.

A 26-year-old male presented with an obstructing calculus in the mid superior-moiety ureter in a duplicated urinary collecting-system. A sequela of the obstruction resulted in a symptomatic stricture in a functional superior-moiety ureter, unresponsive to endoscopic interventions. An ipsilateral robot-assisted laparoscopic side-to-side ureteroureterostomy was performed thus bypassing the stricture in the superior-moiety ureter. Follow up endoscopic visualisation showed a healthy, patent anastomosis. This video presentation shows appropriate positioning, operative technique and follow up for a robot assisted side-to-side ureteroureterostomy. Our minimally invasive novel method is a feasible and safe treatment of a duplex collecting system with a symptomatic ectopic ureter.

Ureteric stenting with magnetic retrieval: an alternative to traditional methods.

INTRODUCTION: Ureteric stents are frequently placed following endo-urological procedures. These stents cause significant morbidity for patients. Standard ureteric stents are removed by flexible cystoscopy. This procedure can be unpleasant for patients and requires additional resources. A newly designed magnetic stent allows removal in an outpatient setting. The aim of our study is to compare the magnetic stent and standard ureteric stents with regard to morbidity, pain on stent removal and cost-effectiveness. METHODS: This study was carried out across two sites between September 2016 and July 2017. In site A, a magnetic stent (Urotech, Black-Star®) is removed by magnetic retrieval device. Fifty consecutive patients completed the validated Ureteric Stent Symptom Questionnaire (USSQ) and visual analogue scale (VAS) at the time of stent removal. On site B, a soft polyurethane stent (Cook Universa) was removed by flexible cystoscopy. Fifty patients were identified retrospectively and completed questionnaires by post. Cost analysis was also performed. RESULTS: One hundred questionnaires were included for analysis. No significant difference in stent morbidity as assessed by the USSQ was shown between both groups. Median duration of stenting was significantly shorter in the magnetic stent group (5.5 versus 21.5 days, p < 0.001). Mean pain on stent removal was significantly less with magnetic retrieval (2.9 versus 3.9, p < 0.05). Complication rates were similar in both groups. Cost analysis showed a cost saving of €203 per patient with the magnetic stent group. CONCLUSION: Magnetic stents cause similar morbidity for patients compared with standard stents removed by flexible cystoscopy; they are associated with less pain at removal and are cost saving.

The sentinel stent? A systematic review of the role of prophylactic ureteric stenting prior to colorectal resections.

PURPOSE: 'Prophylactic' ureteric stents potentially reduce rates, and facilitate intraoperative recognition, of iatrogenic ureteric injury (IUI) during colorectal resections. A lack of consensus surrounds the risk-benefit equation of this practice, and we aimed to assess the evidence base. METHODS: A systematic review was performed according to PRISMA guidelines. MEDLINE, Scopus, EMBASE and Cochrane databases were searched using terms 'ureteric/ureteral/JJ/Double J stent' or 'ureteric/ureteral catheter' and 'colorectal/prophylactic/resection/diverticular disease/diverticulitis/iatrogenic injury'. Primary outcomes were rates of ureteric injuries and their intraoperative identification. Secondary outcomes included stent complication rates. RESULTS: We identified 987 publications; 22 papers met the inclusion criteria. No randomised controlled trials were found. The total number of patients pooled for evaluation was 869,603 (102,370 with ureteric stents/catheters, 767,233 controls). The most frequent indications for prophylactic stents were diverticular disease (45.38%), neoplasia (33.45%) and inflammatory bowel disease (9.37%). Pooled results saw IUI in 1521/102,370 (1.49%) with, and in 1333/767,233 (0.17%) without, prophylactic ureteric stents. Intraoperative recognition of IUIs occurred in 10/16 injuries (62.5%) with prophylactic stents, versus 9/17 (52.94%) without stents (p = 0.579). The most serious complications of prophylactic stent use were ureteric injury (2/1716, 0.12%) and transient ureteric obstruction following stent removal (13/666, 1.95%). CONCLUSIONS: Placement of prophylactic ureteric stents has a low complication rate. There is insufficient evidence to conclude that stents decrease ureteric injury or increase intraoperative detection of IUIs. Apparently higher rates of IUI in stented patients likely reflect use in higher risk resections. A prospective registry with harmonised data collection points and stratification of intraoperative risk is needed.

Contemporary Attitudes and Practice Patterns of North American Urologists in Investigating Stone-Forming Patients-A Survey of Endourological Society Members.

INTRODUCTION: Recent evidence would suggest a low rate of metabolic assessment in stone formers, even in those deemed as high risk. We wished to assess the attitudes and practice patterns of metabolic work up in North American members of the Endourological Society as part of the management of stone-forming patients. METHODS: A 12-question online multiple-choice questionnaire (using Survey Monkey(®)) was distributed to all members of the Endourological Society through e-mail. Descriptive analyses were performed. RESULTS: A total of 124 North American members of the Endourological Society responded (90% endourologists, 65% fellowship trained). Ninety-seven percent perform metabolic assessments without referring to a consultant. Eighty-three percent use a commercial analysis company and 17% request serum or urine parameters individually. Ninety-seven percent believe that 24-48-hour urine collection is a better way of assessing patients for metabolic abnormalities than a "basic analysis." Many respondents (37%) would be more likely to metabolically assess if results were easier to interpret, and 35% would like assistance/advice in the interpretation of results. At initial investigation of a first-time stone former, 87% of respondents use serum chemistry, 48% use 24-hour urine, 26% use 48-hour urine (two consecutive 24-hour urine collections), 54% send stone for analysis, and 7% do not investigate. On recurrent stone formers, 69% use serum chemistry, 73% use 24/48-hour urine, and 23% send stone for analysis. On routine follow-up, 36% check serum chemistry, 55% use 24-hour urine, 2% use 48-hour urine, and 29% do not metabolically evaluate. The majority agree that pharmacologic therapy plays a strong role in preventing recurrence (90%). After initiating pharmacologic therapy, 59% reassess using serum chemistry and 84% and 7% use 24/48-hour urine collection, respectively. Physicians re-evaluate patients after 1 month (7%), 1-2 months (10%), 2-4 months (44%), 4-6 months (30%), or after 6-12 months (7%). CONCLUSION: This snapshot assessment of Endourological Society members' practices in the metabolic investigation of stone-forming patients demonstrates wide testing variations. Many physicians expressed interest in assistance/advice in the interpretation of the metabolic assessment results.

Radiofrequency Ablation-Assisted Zero-Ischemia Robotic Laparoscopic Partial Nephrectomy: Oncologic and Functional Outcomes in 49 Patients.

Introduction and Objectives. Robotic partial nephrectomy with peritumoral radiofrequency ablation (RFA-RPN) is a novel clampless technique. We describe oncologic and functional outcomes in a prospective cohort. Methods. From May, 2007, to December, 2009, 49 consecutive patients with renal masses <7 cm underwent RFA-RPN. During this period, only the RFA-RPN technique was utilized for all cases of partial nephrectomy. Pre- and postoperative data were analyzed and compared to 36 consecutive patients who underwent LPN. Results. In total, 49 tumors were treated in the RFA-RPN group and 36 tumors in the comparison group. Mean operative time was longer in the RFA-RPN group (370 min versus 293 min, p < 0.001). There were no significant differences in mean EBL (231 cc versus 250 cc, p = 0.42), transfusion rate (8.2% versus 11.1%, p = 0.7), or hospital stay (3.9 versus 4.4 days, p = 0.2). Two patients in the RFA-RPN (4.1%) and 1 (2.7%) patient in the comparison group had a positive surgical margin (p = 0.75). 17 (34.7%) patients had a postoperative urine leak in the RFA-RPN group versus 2 (5.6%) patients in the comparison group (p = 0.001). Mean follow-up was 54 months versus 68.4 months in the comparison group. There was no significant difference between the two groups regarding change in GFR (p = 0.67). There were 3 recurrences (6.1%) in the RFA-RPN group and 0 recurrences in the RPN group (p = 0.23). There were 3 deaths (6.1%) in the RFA-RPN group (one cancer specific) and 4 deaths (11.1%) in the RPN group (non-cancer specific) over the follow-up period (p = 0.44). Conclusions. Our data suggests that this technique is associated with a similar degree of renal preservation but higher rates of postoperative urine leak and possibly higher rates of recurrence.

Update on the Diagnosis and Management of Renal Angiomyolipoma.

PURPOSE: Advances in minimally invasive therapies and novel targeted chemotherapeutics have provided a breadth of options for the management of renal masses. Management of renal angiomyolipoma has not been reviewed in a comprehensive fashion in more than a decade. We provide an updated review of the current diagnosis and management strategies for renal angiomyolipoma. MATERIALS AND METHODS: We conducted a PubMed(®) search of all available literature for renal or kidney angiomyolipoma. Further sources were identified in the reference lists of identified articles. We specifically reviewed case series of partial nephrectomy, selective arterial embolization and ablative therapies as well as trials of mTOR inhibitors for angiomyolipoma from 1999 to 2014. RESULTS: Renal angiomyolipoma is an uncommon benign renal tumor. Although associated with tuberous sclerosis complex, these tumors occur sporadically. Risk of life threatening hemorrhage is the main clinical concern. Due to the fat content, angiomyolipomas are generally readily identifiable on computerized tomography and magnetic resonance imaging. However, fat poor angiomyolipoma can present a diagnostic challenge. Novel research suggests that various strategies using magnetic resonance imaging, including chemical shift magnetic resonance imaging, have the potential to differentiate fat poor angiomyolipoma from renal cell carcinoma. Active surveillance is the accepted management for small asymptomatic masses. Generally, symptomatic masses and masses greater than 4 cm should be treated. However, other relative indications may apply. Options for treatment have traditionally included radical and partial nephrectomy, selective arterial embolization and ablative therapies, including cryoablation and radio frequency ablation, all of which we review and update. We also review recent advances in the medical treatment of patients with tuberous sclerosis complex associated angiomyolipomas with mTOR inhibitors. Specifically trials of everolimus for patients with tuberous sclerosis complex suggest that this agent may be safe and effective in treating angiomyolipoma tumor burden. A schema for the suggested management of renal angiomyolipoma is provided. CONCLUSIONS: Appropriately selected cases of renal angiomyolipoma can be managed by active surveillance. For those patients requiring treatment nephron sparing approaches, including partial nephrectomy and selective arterial embolization, are preferred options. For those with tuberous sclerosis complex mTOR inhibitors may represent a viable approach to control tumor burden while conserving renal parenchyma.

Comparative effectiveness of adrenal sparing radical nephrectomy and non-adrenal sparing radical nephrectomy in clear cell renal cell carcinoma: Observational study of survival outcomes.

INTRODUCTION: We compare the survival outcomes of patients with clear cell renal cell carcinoma (RCC) treated with adrenal sparing radical nephrectomy (ASRN) and non-adrenal sparing radical nephrectomy (NASRN). METHODS: We conducted an observational study based on a composite patient population from two university teaching hospitals who underwent RN for RCC between January 2000 and December 2012. Only patients with pathologically confirmed RCC were included. We excluded patients undergoing cytoreductive nephrectomy, with loco-regional lymph node involvement. In total, 579 patients (ASRN = 380 and NASRN = 199) met our study criteria. Patients were categorized by risk groups (all stage, early stage and locally advanced RCC). Overall survival (OS) and cancer-specific survival (CSS) were analyzed for risk groups. Survival analysis was performed using Kaplan-Meier curves and Cox proportional hazards regression. RESULTS: The median follow-up was 41 months (range: 12-157). There were significant benefits in OS (ASRN 79.5% vs. NASRN 63.3%; p = 0.001) and CSS (84.3% vs. 74.9%; p = 0.001), with any differences favouring ASRN in all stage. On multivariate analysis, there was a trend towards worse OS (hazard ratio [HR] 1.759, 95% confidence interval [CI] 0.943-2.309, p = 0.089) and CSS (HR 1.797, 95% CI 0.967-3.337, p = 0.064) in patients with NASRN (although not statistically significant). Of these patients, only 11 (1.9%) had adrenal involvement. CONCLUSIONS: The inherent limitations in our study include the impracticality of conducting a prospective randomized trial in this scenario. Our observational study with a 13-year follow-up suggests ASRN leads to better survival than NASRN. ASRN should be considered the gold standard in treating patients with RCC, unless it is contraindicated.

Modern Guidelines for Bowel Preparation and Antimicrobial Prophylaxis for Open and Laparoscopic Urologic Surgery.

Mechanical bowel preparation (MBP) and antibiotics (oral and/or intravenous) have historically been used to decrease infectious complications in surgeries that involve manipulation of bowel or potential risk of injury. The use of MBP has recently been challenged in the colorectal surgery literature, thus inspiring similar critical evaluation of our practices in urology. This review gives a brief overview of the history of mechanical and oral antibiotic bowel preparation, as well as the evolution of the practice trends in colorectal surgery and urology. We also examine contemporary guidelines in skin preparation as well as antimicrobial prophylaxis before surgery.

The effect of surgical duration of transurethral resection of bladder tumors on postoperative complications: An analysis of ACS NSQIP data.

INTRODUCTION: Transurethral resection of bladder tumor (TURBT) is a common procedure used in the diagnosis and treatment of bladder cancer. Despite how often it is performed, not much is known about the risk factors for complications. Traditional surgery has an increase in morbidity and mortality with increasing operative duration. We assess the effect of operative duration on TURBT complications. METHODS: The years 2006 to 2012 of the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) were queried for patients undergoing TURBT. We separated patients into 4 groups based on operative time: 0 to 30 minutes, 30.1 to 60 minutes, 60.1 to 90 minutes, and greater than 90 minutes. Standard statistical analysis including multivariate regression was performed to determine predictors of complications. RESULTS: A total of 10,599 TURBTs were included in our analysis. The overall complication rate for TURBT was 5.8% and there was an increase in the rate of complications seen as operative duration increased, which remained after controlling for age, comorbidities, tumor size, and American Society of Anesthesiology classification. Increased operative duration was associated with a greater risk of postoperative urinary tract infection, sepsis or septic shock, pulmonary embolism/deep venous thrombosis, reintubation or failure to wean, myocardial infarction, and death. Larger tumors were related to an increased odds of requiring blood transfusions. CONCLUSIONS: Using a contemporary multicenter cohort of TURBTs from the ACS NSQIP database, we demonstrate that increased operative duration is associated with serious postoperative complications. This association was found to persist even after adjusting for patient age, comorbidities, tumor size, and functional status.

Associations of prostate cancer risk variants with disease aggressiveness: results of the NCI-SPORE Genetics Working Group analysis of 18,343 cases.

Genetic studies have identified single nucleotide polymorphisms (SNPs) associated with the risk of prostate cancer (PC). It remains unclear whether such genetic variants are associated with disease aggressiveness. The NCI-SPORE Genetics Working Group retrospectively collected clinicopathologic information and genotype data for 36 SNPs which at the time had been validated to be associated with PC risk from 25,674 cases with PC. Cases were grouped according to race, Gleason score (Gleason ≤ 6, 7, ≥ 8) and aggressiveness (non-aggressive, intermediate, and aggressive disease). Statistical analyses were used to compare the frequency of the SNPs between different disease cohorts. After adjusting for multiple testing, only PC-risk SNP rs2735839 (G) was significantly and inversely associated with aggressive (OR = 0.77; 95 % CI 0.69-0.87) and high-grade disease (OR = 0.77; 95 % CI 0.68-0.86) in European men. Similar associations with aggressive (OR = 0.72; 95 % CI 0.58-0.89) and high-grade disease (OR = 0.69; 95 % CI 0.54-0.87) were documented in African-American subjects. The G allele of rs2735839 was associated with disease aggressiveness even at low PSA levels (<4.0 ng/mL) in both European and African-American men. Our results provide further support that a PC-risk SNP rs2735839 near the KLK3 gene on chromosome 19q13 may be associated with aggressive and high-grade PC. Future prospectively designed, case-case GWAS are needed to identify additional SNPs associated with PC aggressiveness.

Contemporary national surgical outcomes in the treatment of ureteropelvic junction obstruction.

OBJECTIVE: To evaluate contemporary national trends and outcomes of open pyeloplasty (OP) vs minimally invasive pyeloplasty (MIP) in the treatment of ureteropelvic junction obstruction using the National Surgical Quality Improvement Program database. METHODS: Patients treated by OP or MIP between 2006 and 2011 were identified by The International Classification of Diseases, Ninth Revision, Clinical Modification codes corresponding to pyeloplasty as their primary operative procedure. Perioperative variables were analyzed using the chi-square and the Student t test. Multiple logistic regressions were used to identify morbidities and readmission risk factors. RESULTS: Three hundred fifty-five patients were identified. Of them, 20.2% of cases were OP and 79.8% were MIP. There was a significant increase in MIP from 33% in 2006 to 83% in 2011 (P <.001). A total of 11.7% of patients in the MIP group underwent outpatient surgery (P = .002). Patients treated at a teaching hospital were over 3 times more likely to undergo MIP (odds ratio = 3.17; P = .001). There was significantly longer hospitalization in OP vs MIP (3.9 vs. 2.2 days; P = .001). OP was associated with significantly increased risk of reoperation or postoperative morbidity compared with MIP (11.1% vs. 4.2%; P = .02). Multivariate analysis confirmed a higher rate of overall morbidity in the OP cohort (P = .03). Male patients had significantly higher postoperative morbidity or reoperation rates (odds ratio = 4.38; P = .002). There was no significant difference in operative time between groups (P = .2). CONCLUSION: Within the American College of Surgeons National Surgical Quality Improvement Program hospitals, MIP is associated with decreased reoperation and postoperative morbidity compared with OP.

Renal Trauma: The Rugby Factor.

INTRODUCTION: Renal trauma accounts for 5% of all trauma cases. Rare mechanisms of injuries including sports participation are increasingly common. Rugby-related trauma poses a conundrum for physicians and players due to the absence of clear guidelines and a paucity of evidence. Our series highlights traumatic rugby-related renal injuries in our institution, and emphasize the need for international guidelines on management. METHODS: A retrospective review of all abdominal traumas between January 2006 and April 2013, specifically assessing for renal related trauma that were secondary to rugby injuries was performed. All patients' demographics, computerized tomography results, hematological and biochemical results and subsequent management were recorded. RESULTS: Five male patients presented with rugby-related injuries. Mean age was 21 years old. All patients were hemodynamically stable and managed conservatively in acute setting. One patient was detected to have an unknown pre-existing atrophic kidney that had been subsequently injured, and was booked for an elective nephrectomy an 8-week interval. CONCLUSION: Rugby-related trauma has generated essential attention. This paper serves to highlight this type of injury and the need for defined guidelines on role of imaging and international consensus on timing of return to contact sport, in both professional and amateur settings.

Predicting Patients with Inadequate 24- or 48-Hour Urine Collections at Time of Metabolic Stone Evaluation.

PURPOSE: We aimed to understand the characteristics of patients who are less likely to submit adequate urine collections at metabolic stone evaluation. METHODS: Inadequate urine collection was defined using two definitions: (1) Reference ranges for 24-hour creatinine/kilogram (Cr/24) and (2) discrepancy in total 24-hour urine Cr between 24-hour urine collections. There were 1502 patients with ≥1 kidney stone between 1998 and 2014 who performed a 24- or 48-hour urine collection at Northwestern Memorial Hospital and who were identified retrospectively. Multivariate analysis was performed to analyze predictor variables for adequate urine collection. RESULTS: A total of 2852 urine collections were analyzed. Mean age for males was 54.4 years (range 17-86), and for females was 50.2 years (range 8-90). One patient in the study was younger than 17 years old. (1) Analysis based on the Cr 24/kg definition: There were 50.7% of patients who supplied an inadequate sample. Females were nearly 50% less likely to supply an adequate sample compared with men, P<0.001. Diabetes (odds ratio [OR] 1.42 [1.04-1.94], P=0.026) and vitamin D supplementation (OR 0.64 [0.43-0.95], P=0.028) predicted receiving an adequate/inadequate sample, respectively. (2) Analysis based on differences between total urinary Cr: The model was stratified based on percentage differences between samples up to 50%. At 10%, 20%, 30%, 40%, and 50% differences, inadequate collections were achieved in 82.8%, 66.9%, 51.7%, 38.5%, and 26.4% of patients, respectively. Statistical significance was observed based on differences of ≥40%, and this was defined as the threshold for an inadequate sample. Female sex (OR 0.73 [0.54-0.98], P=0.037) predicted supplying inadequate samples. Adequate collections were more likely to be received on a Sunday (OR 1.6 [1.03-2.58], P=0.038) and by sedentary workers (OR 2.3 [1.12-4.72], P=0.023). CONCLUSION: Urine collections from patients during metabolic evaluation for nephrolithiasis may be considered inadequate based on two commonly used clinical definitions. This may have therapeutic or economic ramifications and the propensity for females to supply inadequate samples should be investigated further.

Open vs Minimally Invasive Partial Nephrectomy: Assessing the Impact of BMI on Postoperative Outcomes in 3685 Cases from National Data.

PURPOSE: Previous studies analyzing the relationship between Body Mass Index (BMI) and complications after partial nephrectomy have been underpowered. We use a national surgical database to explore the association of BMI with postoperative outcomes for Open Partial Nephrectomy (OPN) and Minimally Invasive Partial Nephrectomy (MIPN). PATIENTS AND METHODS: Years 2005-2012 of the National Surgical Quality Improvement Program (NSQIP) were queried for OPN and MIPN. Postoperative complications were organized according to Clavien Grades and compared across normal weight (BMI kg/m(2)=18.5-<25.0), overweight (BMI=25.0-<30.0), and obese (BMI≥30.0) patients using standard descriptive statistics and multivariate regression modeling. RESULTS: Of 1667 OPNs and 2018 MIPNs, 46.2% of patients were obese. Operative time was 16.91 minutes longer on average for obese patients (p<0.001). The overall complication rate after OPN was 17.9%, 17.2%, and 17.9% (p=0.945) for normal weight, overweight, and obese patients, respectively; while the overall complication rate after MIPN was 6.9%, 6.3%, and 8.7% (p=0.147). Multivariate regression analysis demonstrated that overweight and obese patients were not at increased risk for any complication grade after OPN and MIPN compared to normal weight patients. When comparing procedures, MIPN had a lower complication rate compared to OPN for obese (8.7% vs 17.9%, p<0.001) and morbidly obese patients (9.2% vs 22.2%, p=0.001). CONCLUSIONS: Although surgery in obese patients is longer compared to normal weight patients, it does not appear to increase the likelihood of 30-day postoperative complications for OPN or MIPN. However, obese patients undergoing MIPN had lower complication rates than those undergoing OPN.

Novel use of carbon dioxide arteriography in renal artery pseudoaneurysm in patients with poor renal function.

Renal artery pseudoaneurysm (RAP) is a rare complication of partial nephrectomy, but is usually effectively managed with renal vessel embolisation. We report a particularly challenging case of a patient with chronic kidney disease (CKD) who developed a RAP following a laparoscopic heminephrectomy and was treated using superselective renal vessel coil embolisation with carbon dioxide (CO2) as the primary contrast agent for arteriographic localisation of the RAP and feeder artery. To the best our knowledge we report the first utilisation of CO2 arteriography in the definitive diagnosis and treatment of RAP following heminephrectomy in a patient with severe CKD.