Is extended preoperative antibiotic prophylaxis for high-risk patients necessary before percutaneous nephrolithotomy?

PURPOSE: The goal of this study was to compare the rate of systemic inflammatory response syndrome (SIRS) in high-risk patients undergoing percutaneous nephrolithotomy (PCNL) between patients who received 7, 2, or 0 days of preoperative antibiotics. MATERIALS AND METHODS: We retrospectively reviewed a series of consecutive PCNLs performed at our institution. Patients with infected preoperative urine cultures were excluded. High-risk patients were defined as those with a history of previous urinary tract infection (UTI), hydronephrosis, or stone size ≥2 cm. Patients were treated with 7, 2, or 0 days of preoperative antibiotic prophylaxis prior to PCNL. All patients received a single preoperative dose of antibiotics within 60 minutes of the start of surgery. Fisher exact test was used to compare the rate of SIRS by preoperative antibiotic length. RESULTS: Of the 292 patients identified, 138 (47.3%) had sterile urine and met high-risk criteria, of which 27 (19.6%), 39 (28.3%), and 72 (52.2%) received 7, 2, and 0 days of preoperative antibiotics, respectively. The 3 groups were similar in age, sex, and duration of surgery (p>0.05). There was no difference in the rate of SIRS between the groups, with 1 of 27 (3.7%), 2 of 39 (5.1%) and 3 of 72 patients (4.2%) meeting criteria in the 7, 2, and 0 days antibiotic groups (p=~1). CONCLUSIONS: Extended preoperative antibiotic prophylaxis was not found to reduce the risk of SIRS after PCNL in our institutional experience of high-risk patients. For these patients, a single preoperative dose of antibiotics is sufficient.

Electronic nutritional intake assessment in patients with urolithiasis: A decision impact analysis.

PURPOSE: To evaluate a physician's impression of a urinary stone patient's dietary intake and whether it was dependent on the medium through which the nutritional data were obtained. Furthermore, we sought to determine if using an electronic food frequency questionnaire (FFQ) impacted dietary recommendations for these patients. MATERIALS AND METHODS: Seventy-six patients attended the Stone Clinic over a period of 6 weeks. Seventy-five gave consent for enrollment in our study. Patients completed an office-based interview with a fellowship-trained endourologist, and a FFQ administered on an iPad. The FFQ assessed intake of various dietary components related to stone development, such as oxalate and calcium. The urologists were blinded to the identity of patients' FFQ results. Based on the office-based interview and the FFQ results, the urologists provided separate assessments of the impact of nutrition and hydration on the patient's stone disease (nutrition impact score and hydration impact score, respectively) and treatment recommendations. Multivariate logistic regressions were used to compare pre-FFQ data to post-FFQ data. RESULTS: Higher FFQ scores for sodium (odds ratio [OR], 1.02; p=0.02) and fluids (OR, 1.03, p=0.04) were associated with a higher nutritional impact score. None of the FFQ parameters impacted hydration impact score. A higher FFQ score for oxalate (OR, 1.07; p=0.02) was associated with the addition of at least one treatment recommendation. CONCLUSIONS: Information derived from a FFQ can yield a significant impact on a physician's assessment of stone risks and decision for management of stone disease.

The role of the assistant during robot-assisted partial nephrectomy: does experience matter?

The objective of this study was to evaluate surgical outcomes with respect to the experience level of the bedside assistant during robot-assisted partial nephrectomy. A retrospective review was conducted of a prospectively maintained database of 414 consecutive robot-assisted laparoscopic partial nephrectomies performed by experienced robotic surgeons at our institution from April 2011 to September 2014. A senior-level assistant was defined as a resident in his or her post-graduate year (PGY) 4 or 5, or a fellow. Junior-level assistants were considered to be PGY-2, PGY-3, or a nurse first assistant. Multivariate analyses were performed using linear, Poisson, and logistic regression models. There were 115 junior-level cases and 299 senior-level cases. On univariate analysis, the experience level of the assistant had no impact on operative time (168 for junior level vs. 163 min for senior level, p = 0.656). Likewise, there were no differences between the junior- and senior-level groups with regard to warm ischemia time (21.3 vs. 20.9 min, p = 0.843), negative margin status (111/115 (96.5 %) vs. 280/299 (93.6 %), p = 0.340), or postoperative complications (17/115 (14.8 %) vs. 35/299 (11.7 %), p = 0.408). After multivariate analysis, operative time was associated with increased body mass index and tumor size (both p < 0.001), but not with resident experience level (p = 0.051). Estimated blood loss and postoperative complications were also not associated with the PGY of the assistant (p = 0.488 and p = 0.916, respectively). Despite common concern, the PGY status of a physician trainee serving as the bedside assistant does not appear to influence the outcomes of robot-assisted partial nephrectomy at a high-volume center.

Review of robot-assisted partial nephrectomy in modern practice.

Partial nephrectomy (PN) is currently the standard treatment for T1 renal tumors. Minimally invasive PN offers decreased blood loss, shorter length of stay, rapid convalescence, and improved cosmesis. Due to the challenges inherent in laparoscopic partial nephrectomy, its dissemination has been stifled. Robot-assisted partial nephrectomy (RAPN) offers an intuitive platform to perform minimally invasive PN. It is one of the fastest growing robotic procedures among all surgical subspecialties. RAPN continues to improve upon the oncological and functional outcomes of renal tumor extirpative therapy. Herein, we describe the surgical technique, outcomes, and complications of RAPN.

In vivo evaluation of a reverse thermosensitive polymer for ureteroscopy with laser lithotripsy: porcine model.

PURPOSE: To evaluate the effects of a reverse thermosensitive polymer during ureteroscopy with laser lithotripsy in an in vivo porcine model. MATERIALS AND METHODS: Six pigs underwent general anesthesia followed by bilateral ureteroscopy with laser lithotripsy of stone phantoms while measuring intrapelvic renal pressures through bilateral nephrostomy tubes. The procedures were performed in one ureter with the reverse thermosensitive polymer and in the contralateral, control ureter without the reverse thermosensitive polymer. Stone migration lengths, operative times, laser times, laser energy usage, intrapelvic pressures, and postnecropsy histologic examinations of the ureters were compared between the two groups. RESULTS: Bilateral ureteroscopy with lithotripsy was successfully performed in five of six pigs. In one pig, only the unilateral control was performed, because the ureter was too narrow to complete the contralateral side. The mean laser time was 12.8 minutes shorter with the use of the reverse thermosensitive polymer group than in the controls (P=0.021). The procedure time, laser energy usage, and retropulsion length was shorter in the reverse thermosensitive polymer group, but did not reach significance. Between the two groups, there was no difference in mean renal pelvic pressures, peak renal pelvic pressures, or postprocedure histologic examinations of the ureters. CONCLUSIONS: The use of a reverse thermosensitive polymer during ureteroscopy with lithotripsy may have greater advantages beyond preventing stone retropulsion. Here, the use of a reverse thermosensitive polymer during ureteroscopy with lithotripsy resulted in a significant decrease in laser times. Further clinical investigations could further delineate the advantages of using a reverse thermosensitive polymer during intracorporeal lithotripsy.

Endoscopic management of genitourinary foreign bodies.

Retrieval of foreign bodies from the genitourinary system, most commonly inserted for sexual satisfaction or as a result of a psychiatric illness, can pose a significant surgical challenge. Due to their breadth of size, shape, and location within the genitourinary system, endoscopic management can be difficult. Here, we review the management of four cases of foreign object insertion into the genitourinary system and their outcomes and management.

Gas-producing renal infection presenting as pneumaturia: a case report.

We present a case of persistent pneumaturia of one-year duration in a fifty-five-year-old male with a history of spinal cord injury. The evaluation demonstrated gas throughout the collecting system attributable to a urinary tract infection with a gas-forming organism, Klebsiella pneumoniae.

Percutaneous cryoablation of renal masses: Washington University experience of treating 129 tumours.

UNLABELLED: WHAT'S KNOWN ON THE SUBJECT? AND WHAT DOES THE STUDY ADD?: For patients who are unfit for extirpative surgery, percutaneous cryoablation (PCA) presents a minimally-invasive alternative for the treatment of renal masses. PCA has been demonstrated to be safe, with complication rates <10% being reported consistently. Studies have suggested that a minimal and insignificant decline in renal function can occur after PCA. Finally, among studies with a follow-up >20 months, treatment success rates range from 75% to 96%. However, longer-term oncological and functional results for patients treated with PCA are relatively limited. The present study profiles one of the largest reported experiences with PCA for renal masses: 129 tumours in 124 patients. Our complication rate was comparable to that observed in other reported studies. At a mean follow-up of 30 months, treatment success was achieved in 87% of tumours, which is in line with published PCA success rates. On multivariable analysis, tumour size >3.0 cm was found to be significantly associated with treatment failure. A minimal but statistically significant renal functional decline was observed, with 20% of patients experiencing a progression in National Kidney Foundation-Chronic Kidney Disease stage. On multivariable analysis, age >70 years, hilar tumour location and postoperative day 1 estimated glomerular filtration rate <60 mL/min/1.73 m(2) were found to be significantly associated with renal functional decline. The present study confirms that PCA of renal masses represents a safe alternative to surgery in patients with substantial medical comorbidities. In the present cohort, baseline patient and tumour characteristics probably impact the risk of tumour recurrence, as well as renal disease progression, after PCA. OBJECTIVE: To evaluate perioperative, oncological and functional outcomes after percutaneous cryoablation (PCA) for renal masses based on our single-centre experience. PATIENTS AND METHODS: We retrospectively identified 124 patients who underwent PCA for 129 renal tumours between March 2005 and June 2011. Patient demographics and baseline clinical characteristics, tumour features, perioperative information, and postoperative outcomes were recorded. Oncological outcomes were defined by radiographic evidence of recurrence on follow-up computed tomography or magnetic resonance imaging. Renal disease progression was defined by a change in National Kidney Foundation-Chronic Kidney Disease stage. RESULTS: Patients had mean (sd) age of 72.6 (10.2) years; mean (sd) tumour size and nephrometry score were 2.7 (1.1) cm and 6.5 (1.7), respectively. Our overall complication rate was 9% (11/124), whereas the major (greater than Clavien II) complication rate was 2% (2/124). Significant predictors of renal disease progression following PCA included age ≥ 70 years (odds ratio [OR], 4.31, P = 0.03), hilar tumour location (OR, 4.67, P = 0.04), and post operative day 1 estimated glomerular filteration rate ≤60 mL/min/1.73 m(2) (OR, 7.09, P = 0.02). Our treatment success rate was 87% (112/129) at a mean (sd) follow-up of 30.2 (18.8) months. Tumour size ≥3.0 cm was significantly associated with PCA failure (hazard ratio, 3.21, P = 0.03). CONCLUSION: PCA provides a safe and oncologically effective alternative to extirpative surgery for renal masses in patients with significant medical comorbidities.

2D versus 3D visualization: impact on laparoscopic proficiency using the fundamentals of laparoscopic surgery skill set.

INTRODUCTION: We compared the impact of two-dimensional (2D) versus three-dimensional (3D) visualization on both objective and subjective measures of laparoscopic performance using the validated Fundamentals of Laparoscopic Surgery (FLS) skill set. SUBJECTS AND METHODS: Thirty-three individuals with varying laparoscopic experience completed three essential drills from the FLS skill set (peg transfer, pattern cutting, and suturing/knot tying) in both 2D and 3D. Participants were randomized to begin all tasks in either 2D or 3D. Time to completion and number of attempts required to achieve proficiency were measured for each task. Errors were also noted. Participants completed questionnaires evaluating their experiences with both visual modalities. RESULTS: Across all tasks, greater speed was achieved in 3D versus 2D: peg transfer, 183.4 versus 245.6 seconds (P<.0001); pattern cutting, 167.7 versus 209.3 seconds (P=.004); and suturing/knot tying, 255.2 versus 329.5 seconds (P=.031). Fewer errors were committed in the peg transfer task in 3D versus 2D (P=.008). Fourteen participants required multiple attempts to achieve proficiency in one or more tasks in 2D, compared with 7 in 3D. Subjective measures of efficiency and accuracy also favored 3D visualization. The advantage of 3D vision persisted independent of participants' level of technical expertise (novice versus intermediate/expert). There were no differences in reported side effects between the two visual modalities. Overall, 87.9% of participants preferred 3D visualization. CONCLUSIONS: Three-dimensional vision appears to greatly enhance laparoscopic proficiency based on objective and subjective measures. In our experience, 3D visualization produced no more eye strain, headaches, or other side effects than 2D visualization. Participants overwhelmingly preferred 3D visualization.

Laparoscopic cryoablation of renal masses: single-center long-term experience.

OBJECTIVE: To evaluate perioperative and long-term functional and oncological outcomes of laparoscopic cryoablation (LCA) performed at Washington University. METHODS: A retrospective chart review was performed evaluating 62 consecutive patients who underwent LCA at our institution between 2000 and 2005. RESULTS: Mean age-adjusted Charlson Comorbidity Index (CCI) was 6.1 (SD, 2.1; 95% confidence interval [CI], 5.6-6.6). Mean tumor size was 2.52 cm (SD, 0.99; CI, 2.3-2.8). Mean operative time was 162.0 minutes (SD, 66.6; CI, 142.0-182.1). Mean estimated blood loss was 84.9 mL (SD, 102; CI, 58.6-111.2). Mean hospital stay was 2.6 days (SD, 1.90; CI, 2.1-3.1). The perioperative complication rate was 9.7% (Clavien 1-2). Among patients with biopsy proven, localized renal cell carcinoma, the 6-year Kaplan-Meier estimated disease-free survival (DFS) was 80%; cancer-specific survival (CSS) was 100%; and overall survival (OS) was 76.2%. Mean follow-up in this subset was 76.0 months (SD, 39.3; CI, 62.7-89.4; n = 35), whereas mean time to cancer recurrence was 27.6 months (SD, 11.2; CI, 15.9-39.3; n = 6). Tumor size ≥2.6 cm was the only predictor of cancer recurrence in a multivariate Cox proportional hazards model (hazard ratio [HR] = 28.9; P = .046; n = 35). Mean preoperative estimated glomerular filtration rate (eGFR) was 68.3 (SD, 22.3; CI, 62.1-74.5), compared to 64.5 mL/min/1.73 m(2) (SD, 28.9; CI, 56.5-72.6) at last follow-up (P = .12; n = 52). Excluding patients requiring secondary ablative or extirpative treatments for recurrent renal cell carcinoma, preoperative eGFR <60 mL/min/1.73 m(2) (odds ratio [OR] = 88.3; P = .036) and age-adjusted CCI ≥6 (OR = 32.4; P = .046) were the only factors predicting renal disease progression on multiple logistic regression (n = 47). CONCLUSION: We report what is by far the longest follow-up to date of postlaparoscopic cryoablation changes in eGFR and note excellent long-term renal functional outcomes. For those willing to accept the potential need for retreatment for recurrent disease, LCA offers excellent long-term CSS.

Robot-assisted pyeloplasty: outcomes for primary and secondary repairs, a single institution experience.

INTRODUCTION: Robotic Pyeloplasty (RAP) is a technique for management of ureteropelvic junction obstruction (UPJO). PURPOSE: To report outcomes of RAP for primary and secondary (after failed primary treatment) UPJO. MATERIALS AND METHODS: Single institution data of adult RAP performed from 2007 to 2009 was collected retrospectively following approval by our IRB. Database analysis included patient age, race, pre and post-operative imaging studies and perioperative variables including operative time, blood loss, pain and complications. RESULTS: Fifty-five adult patients underwent RAP (26 left/29 right) for UPJO including 9 secondary procedures from 2007 to 2009. Average follow-up was 16 months (1-36). Mean age was 41 years (18-71) with an average BMI of 27 (17-42); 32 were female. Most patients were diagnosed with preoperative diuretic renal scintigraphy and the obstructed side demonstrated mean function of 41% and t1/2 of 70 minutes. Mean operative time was 194 minutes with average blood loss less than 100 mL. Mean hospital stay was 1.7 days with an average narcotic equivalent dose of 15 mg. RAP for secondary UPJO took longer with more blood loss and had a lower success rate. Failure was defined as the need of another procedure due to persistent pain and/or obstruction after diuretic renal imaging. One patient (2%) with primary UPJO failed and 2 patients (22%) with secondary UPJO failed. One major complication occurred. CONCLUSION: RAP is a good option for the treatment of patients with UPJO. Reported series have established that endopyelotomy has inferior success rate for the treatment of primary UPJO which compromises the success of subsequent treatment as demonstrated in our higher failure rate with secondary UPJO repair.

Robot-assisted pyeloplasty: outcomes for primary and secondary repairs, a single institution experience

INTRODUCTION: Robotic Pyeloplasty (RAP) is a technique for management of uretero-pelvic junction obstruction (UPJO). PURPOSE: To report outcomes of RAP for primary and secondary (after failed primary treatment) UPJO. MATERIALS AND METHODS: Single institution data of adult RAP performed from 2007 to 2009 was collected retrospectively following approval by our IRB. Database analysis including patient age, race, pre and post-operative imaging studies and perioperative variables including operative time, blood loss, pain and complications. RESULTS: Fifty-five adult patients underwent RAP (26 left/29 right) for UPJO including 9 secondary procedures from 2007 to 2009. Average follow-up was 16 months (1-36). Mean age was 41 years (18-71) with an average BMI of 27 (17-42), 32 were female. Majority were diagnosed with preoperative diuretic renal scintigraphy with obstructed side demonstrating mean function of 41% and t1/2 of 70 minutes. Mean operative time was 194 minutes with average blood loss less than 100 mL. Mean hospital stay was 1.7 days with an average narcotic equivalent dose of 15 mg. RAP for secondary UPJO took longer with more blood loss and had a lower success rate. Failure was defined as necessitating another procedure due to persistent pain and/or obstruction on diuretic renal imaging. One patient (2%) with primary UPJO failed and 2 patients (22%) with secondary UPJO failed. One major complication occurred. CONCLUSION: RAP is a good option for the treatment of patients with UPJO. Reported series have established that endopyelotomy has inferior success as a treatment for primary UPJO which compromises the success of subsequent treatment as demonstrated in our higher failure rate with secondary UPJO repair.

Partial nephrectomy in two patients with known T3a tumours involving the renal vein.

UNLABELLED: Study Type--Therapy (case series). Level of Evidence 4. What's known on the subject? And what does the study add? Although nephron-sparing surgery (NSS) has became accepted therapy for T1 tumours, radical nephrectony is considered the best therapy for T3a tumours involving the renal vein. NSS can be considered in T3a or greater tumours if imperative indications exist, such as bilateral disease or solitary kidney. However, there is little published data on the characteristics of these patients, the impact of surgery on their renal function, and long-term oncologic outcomes. This study profiles single-institution experience with nephron-sparing surgery for known T3a tumours involving the renal vein, including patient characteristics, tumour characteristics, preoperative and follow-up imaging, preoperative and follow-up estimated glomerular filtration rate, length of temporary postoperative haemodialysis, and oncologic outcome. Additionally, we compare this to other published data on nephron-sparing surgery for similar tumors. OBJECTIVE: • To present two patients with T3a tumours involving the renal vein who underwent nephron-sparing surgery (NSS) for imperative reasons. PATIENTS AND METHODS: • Retrospective chart review of patients who underwent NSS for renal cell carcinoma (RCC) with known renal vein tumour thrombus (RVTT). • Both patients underwent open partial nephrectomy and renal vein thrombectomy of a solitary kidney. • Primary outcomes of the study include radiographic evidence of recurrence, haemodialysis requirement and estimated glomerular filtration rate (eGFR) before and after surgery. RESULTS: • Patient 1 is 24 months from NSS and has no evidence of recurrence based on CT scan. His final pathology revealed a 9-cm, T3a, clear cell, Fuhrman grade II carcinoma. He spent 42 days on haemodialysis and is now off all dialysis. His preoperative and most recent eGFR are 48 and 23 mL/min/1.73 m(2) based on the Modification of Diet in Renal Disease (MDRD) equation and 69.4 and 29.8 mL/min by the Cockcroft-Gault equation. • Patient 2 is 9 months from NSS and has no evidence of recurrence based on CT scan. Her final pathology revealed a 6-cm, T3a, clear cell, Fuhrman grade II-III carcinoma. She spent 30 days on haemodialysis and is now off all dialysis. Her preoperative and most recent eGFR are 58 and 30 mL/min/1.73 m(2) based on the MDRD equation and 62.2 and 32.8 mL/min by the Cockcroft-Gault equation. CONCLUSION: • Based on our review, preservation of renal function and favourable oncological outcome can be accomplished with NSS in patients with known stage T3a RCC with RVTT and should be considered in carefully selected patients.

Surgical outcomes of robot-assisted partial nephrectomy.

• Robot-assisted partial nephrectomy (RAPN) has emerged as a viable technique for nephron-sparing surgery. • In this article, we review the outcomes of RAPN in its current iteration, with attention to operative, oncological, and functional outcomes. In addition, we highlight techniques that may serve to enhance outcomes.

Renal tumor models: evaluation of ease of implementation, quality of composition, and imaging characteristics.

BACKGROUND AND PURPOSE: With the rise in detection of small renal masses that are amenable to nephron-sparing surgical approaches, there has been an increasing need for renal tumor models that create discrete lesions suitable for training exercises. We aim to investigate a handful of commonly used compounds, subjectively evaluating their ease of implementation and imaging characteristics. MATERIALS AND METHODS: After an initial ex vivo study, we selected five compounds for an in vivo porcine investigation. These compounds included metagel with barium, Smooth-Cast 320, Silfome with and without barium, and Kromopan. The compounds were injected under laparoscopic guidance with the aim of creating discrete renal tumors. The kidneys were then imaged under ultrasonography and CT. The animals were euthanized, and nephrectomy was performed. Handling characteristics were noted. RESULTS: All compounds were relatively easy to inject. Most of the compounds were susceptible to some degree of subcapsular spread. Kromopan had a high propensity for infiltration of the collecting system. On imaging, metagel was clearly distinguishable from normal renal parenchyma on both CT and ultrasonography. Silfome and Smooth-Cast were difficult to resolve on ultrasonography. Metagel was prone to rupture during surgical manipulation. CONCLUSIONS: No single compound provided the ideal combination of ease of implementation, resistance to extravasation, ease of resolution on imaging, and resistance to rupture. Therefore, compound selection should be dictated by the particular aims of a training simulation.

Positive margin during partial nephrectomy: does cancer remain in the renal remnant?

OBJECTIVE: To examine the outcomes of patients with a positive surgical margin by gross and/or frozen examination during partial nephrectomy, in whom a re-resection of the margin or a completion nephrectomy was performed. METHODS: Patients with renal cancer who underwent partial nephrectomy were considered. If the patient had a positive margin and underwent completion nephrectomy or re-excision of the margin, they were included. Patients with planned enucleation were excluded from the study. Clinical and pathologic information were reviewed to examine for residual cancer in the additionally resected tissue. RESULTS: In the final cohort, 29 patients with a positive margin and subsequent complete parenchymal re-resection or completion nephrectomy were identified. Eight patients underwent nephrectomy, after which no residual cancer was found in the renal remnant. Twenty-one patients underwent total re-resection of the margin, of which two were found to have carcinoma. Renal functional outcomes revealed a decrease in estimated glomerular filtration rate of 25 mL/min/1.73 m(2) in patients who underwent radical nephrectomy, and 4 mL/min/1.73 m(2) in patients who underwent re-resection of the margin with preservation of the renal unit. CONCLUSIONS: A positive surgical margin does not necessarily mean that cancer remains in the renal remnant in most cases. Therefore, radical nephrectomy or re-resection of the margin is overtreatment in many cases, but a small percentage of patients will harbor residual malignancy. Clinical correlation is recommended before reexcision or completion nephrectomy after a positive surgical margin, with careful consideration of the impact on subsequent renal function weighed against the possibility of residual disease.