How I Do It: ERAS protocol featuring erector spinae plane block for percutaneous nephrolithotomy.

Percutaneous nephrolithotomy (PCNL) is the gold-standard treatment for large and complex renal stones. Though associated with higher stone-free rates compared to other minimally invasive stone procedures, this comes at the expense of increased morbidity including postoperative pain and discomfort. We describe our enhanced recovery after surgery (ERAS) protocol for PCNL with emphasis on the use of erector spinae plane blocks to improve patient satisfaction and reduce postoperative opioid use and bother.

LeGrand N. Denslow: Pioneer in dermatology or charlatan?

LeGrand N. Denslow (1852-1918) was a pioneer of American dermatology and one of its most controversial figures. His professional career revolved around the cities of New York; St. Paul; Minnesota; and London, England. In 1885, he became professor of skin diseases and genitourinary surgery, and secretary of the St. Paul Medical College, thus making him one of the earliest dermatologists to practice in the state of Minnesota. In 1908, Denslow created a sensation in the news media when he announced, in a paper read before the New York Academy of Medicine, that he had cured patients suffering from tabes dorsalis by treating various abnormalities that he had found in their urethras. Although some American physicians hailed Denslow's "cure" as a major advance in the treatment of tabetic patients, other physicians denounced his treatments as being worthless or, at best, providing minimal and transient symptomatic benefits. This contribution presents the highlights of Denslow's personal life and professional career. It also describes his urologic treatment of tabes dorsalis and the controversy that surrounded it.

Frailty as predictor of complications in patients undergoing percutaneous nephrolithotomy (PCNL).

INTRODUCTION & OBJECTIVE: Surgical complications are difficult to predict, despite existing tools. Frailty phenotype has shown promise estimating postoperative risk among the elderly. We evaluate the use of frailty as a predictive tool on patients undergoing percutaneous renal surgery. METHODS: Frailty was prospectively analyzed using the Hopkins Frailty Index, consisting of 5 components yielding an additive score: patients categorized not frail, intermediate, or severely frail. Primary outcomes were complications during admission and 30-day complication rate. Secondary outcomes included overall hospital length of stay (LOS) and discharge location. RESULTS: A total of 100 patients recruited, of whom five excluded as they did not need the procedure. A total of 95 patients analyzed; 69, 10, and 16 patients were not frail, intermediate, and severely frail, respectively. There were no differences in blood loss, number of dilations, presence of a staghorn calculus, laterality, or location of dilation. Severely frail patients were likely to be older and have a higher American Society of Anesthesiologists score and Charlson comorbidity index. Patients of intermediate or severe frailty were more likely to exhibit postoperative fevers, bacteremia, sepsis, and require ICU admissions (P < 0.05). Frail patients had a longer LOS (P < 0.001) and tended to require skilled assistance when discharge (p < 0.0001). CONCLUSIONS: Frailty assessment appears useful stratifying those at risk of extended hospitalization, septic complications, and need for assistance following percutaneous renal surgery. Risks of sepsis, bacteremia, and post-operative hemorrhage may be higher in frail individuals. Preoperative assessment of frailty phenotype may give insight into treatment decisions and represent a modifiable marker allowing future trials exploring the concept of "prehabilitation".

Efficacy of Multi-Detector Computed Tomography for the Diagnosis of Medullary Sponge Kidney.

OBJECTIVE: To expand the diagnostic armamentarium for medullary sponge kidney (MSK), we evaluate the use of high-resolution multidetector computed tomography (MDCT) for MSK diagnosis and compare to the standard intravenous urography (IVU). Despite a significant prevalence amongst stone formers, diagnosis of this well described condition has declined. IVU, the gold standard in MSK diagnosis, has largely been replaced by CT, which has previously been shown unable to demonstrate signs of MSK. METHODS AND MATERIALS: Patients with known history of MSK based on IVU underwent limited MDCT urogram. Control group patients, without MSK, also had MDCT urograms performed for other clinically indicated conditions. Studies were scored by board-certified radiologists on a 0-2 scale based on the likelihood of MSK. IVU studies, when available, were similarly graded. RESULTS: MDCT was diagnostic of MSK in 9 out of the 10 patients with known history of MSK. No false positives were present in our series. The one case of MSK not detected on MDCT was graded as a "1" on its respective IVU. Sensitivity and specificity were 90 and 100%, respectively, when compared with IVU. CONCLUSION: Concordance with IVU findings, despite a small reduction in sensitivity, indicates MDCT to be a suitable, and more readily available replacement for IVU in the diagnosis of MSK.

Incorporation of the fluoroless C-Arm Trainer at the American Urological Association hands on training percutaneous renal access.

OBJECTIVES: To assess for usefulness and validity evidence for incorporating the C-Arm Trainer (CAT) simulator into the annual AUA hands on course for training percutaneous nephrolithotomy (PCNL). MATERIALS AND METHODS: The course started with a didactic session followed by four stations for training the "bull's eye" technique using the CAT simulator. Each station included a pre-test, 30-min practice on the simulator, and post-test. All participants were assessed using a 4-item checklist. All participants were asked to fill in a qualitative self-assessment questionnaire after the pre- and the post-test, and respond to a course evaluation questionnaire and post-course survey. RESULTS: A total of 38 physicians, who attended the hands on course, voluntarily participated in the study. Only 21.1% had previous practice on PCNL simulators. Compared with the results of the checklist total score and the qualitative self-assessment questionnaire scores after the pre-test, there was significant improvement in the checklist total score (p < 0.001), temporal demands (p = 0.003), situational stress (p = 0.003, and performance (0.003) after the post-test. A total of 14 (36%) participants responded to the course evaluation questionnaire, 50% evaluated the course as excellent, 28.6% as very good, and 21.4% as good. Unfortunately, only five (13%) participants responded to the post-course survey, 4/5 implemented the new competencies and knowledge into their practice, and 3/5 have attempted to obtain fluoroscopic guided PCA without assistance. CONCLUSION: The CAT simulator was considered useful for training the percutaneous renal access procedure. There was significant improvement in the qualitative and quantitative assessment parameters after the post-test compared with the pre-test.

Prediction of surgical complications in the elderly: Can we improve outcomes?

As the number of Americans aged 65 years and older continues to rise, there is projected to be a corresponding increase in demand for major surgeries within this population. Consequently, it is important to utilize accurate preoperative risk stratification techniques that are applicable to elderly individuals. Currently, commonly used preoperative risk assessments are subjective and often do not account for elderly-specific syndromes that may pose a hazard for geriatric patients if not addressed. Failure to accurately risk-stratify these patients may increase the risk of postoperative complications, morbidity, and mortality. Therefore, we aimed to identify and discuss the more objective and better-validated measurements indicative of poor surgical outcomes in the elderly with special focus on frailty, patient optimization, functional status, and cognitive ability.

A Randomized Controlled Comparison of Nephrostomy Drainage vs Ureteral Stent Following Percutaneous Nephrolithotomy Using the Wisconsin StoneQOL.

OBJECTIVE: We compared postoperative outcomes and quality of life (QoL) between patients who received a nephrostomy tube vs a ureteral stent following percutaneous nephrolithotomy (PCNL) in a prospective, double-blind, randomized manner. MATERIALS AND METHODS: Between September 2015 and March 2016, we randomized 30 patients undergoing PCNL to receive nephrostomy drainage (Group 1: 8F or 10F) or Double-J ureteral stent (Group 2) at conclusion of surgery. Nephrostomy tubes were removed within 48 hours (before discharge) and ureteral stents were removed at least 2 weeks after surgery. Patients' QoL was assessed with the Wisconsin StoneQOL questionnaire preoperatively and then 7 to 10 days and 30 days following surgery. Inclusion criteria included an uncomplicated procedure, normal preoperative renal function, and clinically insignificant residual stone fragments on postoperative imaging. We calculated the preoperative and postoperative QoL score difference between the two groups. We also evaluated perioperative characteristics, inpatient analgesic requirements, length of stay (LOS), and postsurgical complications. OUTCOME: Patient characteristics between Groups 1 and 2 were comparable with similar age (58.3 vs 54.7, p = 0.534), gender ratio, and stone burden (276.6 mm2 vs 259 mm2, p = 0.84) and composition. There was no significant difference between perioperative outcomes, including stone-free rate (93.3% vs 86.7%), operative times (125.7 minutes vs 115 minutes, p = 0.29), estimated blood loss (103.3 mL vs 100.7 mL, p = 0.9), LOS (3.2 days vs 1.9 days, p = 0.1), and complications (2 in each group). Inpatient analgesic requirements were also the same (both 21.1 mg, p = 1.0). Assessment of QoL using the Wisconsin StoneQOL questionnaire showed significant differences between preoperative and postoperative health-related QoL in 18 of the 28-question instrument at 7 to 10 days. Patients in Group 2 had significantly worse QoL change and a multitude of negative responses on the StoneQOL assessment, not only those commonly associated with stent irritation. Eighty percent of participants in Group 2 also attributed their complaints to having a stent placed. Both groups had similar QoL status at 30 days after surgery. CONCLUSION: Despite the literature advocating "tubeless" PCNL with ureteral stent placement at conclusion of surgery, our randomized prospective study shows that QoL is significantly worse with stent placement than with temporary nephrostomy drainage in the immediate aftermath following PCNL, using a validated QoL assessment instrument specific for nephrolithiasis.

Stenting for malignant ureteral obstruction: Tandem, metal or metal-mesh stents.

Extrinsic malignant compression of the ureter is not uncommon, often refractory to decompression with conventional polymeric ureteral stents, and frequently associated with limited survival. Alternative options for decompression include tandem ureteral stents, metallic stents and metal-mesh stents, though the preferred method remains controversial. We reviewed and updated our outcomes with tandem ureteral stents for malignant ureteral obstruction, and carried out a PubMed search using the terms "malignant ureteral obstruction," "tandem ureteral stents," "ipsilateral ureteral stents," "metal ureteral stent," "resonance stent," "silhouette stent" and "metal mesh stent." A comprehensive review of the literature and summary of outcomes is provided. The majority of studies encountered were retrospective with small sample sizes. The evidence is most robust for metal stents, whereas only limited data exists for tandem or metal-mesh stents. Metal and metal-mesh stents are considerably more expensive than tandem stenting, but the potential for less frequent stent exchanges makes them possibly cost-effective over time. Urinary tract infections have been associated with all stent types. A wide range of failure rates has been published for all types of stents, limiting direct comparison. Metal and metal-mesh stents show a high incidence of stent colic, migration and encrustation, whereas tandem stents appear to produce symptoms equivalent to single stents. Comparison is difficult given the limited evidence and heterogeneity of patients with malignant ureteral obstruction. It is clear that prospective, randomized studies are necessary to effectively scrutinize conventional, tandem, metallic ureteral and metal-mesh stents for their use in malignant ureteral obstruction.

The visceral fat compartment is independently associated with changes in urine constituent excretion in a stone forming population.

The objective of this study was to identify the independent effect of visceral fat on urine constituent excretion in a stone forming population. Using a database of 382 kidney stone patients with available visceral fat quantification, we created multiple linear regression models predicting changes in urinary solutes based on visceral fat area and body mass-index, divided by gender. Chi-square tests were used to compare stone composition by body mass-index and visceral fat area. Visceral fat predicts increases in urinary creatinine, sodium, and volume in men, but only urinary phosphate in women. In women, total body mass-index does not appear to modify this effect, but in men it is more pronounced in overweight patients for creatinine and volume only. Elevated visceral fat is associated with increased probability of uric acid stone composition. Different fat compartments likely effect urine composition in different ways. This effect appears to be different in men and women. Understanding and quantifying the effects of different fat compartments is probably important to understanding the metabolism of urolithiasis.

Does hypertension impact 24-hour urine parameters in patients with nephrolithiasis?

OBJECTIVE: To examine the differences in 24-hour urine parameters and stone composition between patients with and without systemic hypertension (HTN) in a large cohort of stone formers. MATERIALS AND METHODS: We performed a retrospective review over a 10-year period of patients with stone, who had completed a 24-hour urinalysis (Litholink) and for whom demographic information was available, including the presence of HTN. Univariate and multivariate analyses were performed, comparing the 24-hour urinalysis profiles of patients with HTN with that of normotensive patients. RESULTS: Of the 1115 patients eligible for inclusion, 442 patients (40%) had HTN and 673 (60%) did not. Patients with HTN were significantly older, had a higher body mass index, and had a greater number of comorbid conditions than normotensive patients. Univariate analysis revealed significantly lower urine pH, calcium, supersaturation (SS) of calcium oxalate (CaOx) and SS calcium phosphate (all P <.05) in patients with HTN. Multivariate analysis showed significantly lower calcium, citrate, and SS CaOx in patients with HTN (all P <.05). CONCLUSION: Our results demonstrate lower levels of calcium and SS CaOx on univariate and multivariate analysis, as well as lower levels of citrate on multivariate analysis in patients with HTN. These results suggest that lower levels of citrate may contribute to stone formation to a greater degree in patients with HTN than abnormalities in calcium metabolism.

Percutaneous nephrolithotomy during uninterrupted aspirin therapy in high-cardiovascular risk patients: preliminary report.

OBJECTIVE: To determine the feasibility and safety of performing percutaneous nephrolithotomy (PCNL) in high-cardiovascular risk patients remaining on aspirin therapy. METHODS: We retrospectively reviewed all PCNLs performed by 3 fellowship-trained endourologists at a single institution between July 2012 and January 2014. All patients remaining on aspirin for imperative indications through the day of surgery were evaluated for surgical outcomes and thromboembolic events. RESULTS: Of 281 PCNL procedures performed during the study period, 16 (5.7%) were performed in 14 patients taking aspirin, uninterrupted, through surgery. Mean surgery time was 66 minutes, mean estimated blood loss was 161 mL, and mean length of hospital stay was 2.8 days. All patients were stone free. There were no intraoperative complications. A total of 5 patients experienced a postoperative complication (n = 4, Clavien grade II; n = 1, Clavien grade IIIa). No patient experienced a perioperative thromboembolic or cardiac event. Three patients required a blood transfusion postoperatively, and none experienced delayed renal bleeding. CONCLUSION: PCNL can be performed safely and effectively in high-cardiovascular risk patients continuing aspirin perioperatively. Compared with the potential sequelae of a thromboembolic or cardiac event, PCNL is associated with an acceptably low transfusion rate, and should be considered a viable treatment option for large renal stones in this population.

Continuing aspirin therapy during percutaneous nephrolithotomy: unsafe or under-utilized?

INTRODUCTION: Aspirin, as an inhibitor of platelets, is traditionally discontinued prior to percutaneous nephrolithotomy (PCNL) given the concern for increased surgical hemorrhage. However, this practice is based on expert opinion only, and mounting evidence suggests holding aspirin perioperatively can be more harmful than once thought. We sought to compared PCNL outcomes and complications in patients continuing aspirin to those stopping aspirin perioperatively. METHODS: A retrospective review was performed of 321 consecutive PCNLs done between July 2012 and March 2014. Patients were separated into two groups. The on-aspirin group consisted of patients continuing aspirin throughout the perioperative period. The off-aspirin group had aspirin held temporarily pre- and postoperatively. Surgical outcomes and complications were compared between groups. RESULTS: Of the 321 PCNLs, 60 (18.7%) occurred in patients chronically taking aspirin. The on-aspirin group included 17 PCNLs (5.2%), while the off-aspirin group included 43 PCNLs (13.4%). There were no differences between groups in terms of operative time (77 minutes vs 74 minutes, p=0.212), hemoglobin change (p=0.522), stone size (21 mm vs 22 mm, p=1.0), stone-free rate (p=0.314), median length of hospitalization (p=0.642), transfusion rate (p=0.703), or total complications (p=1.0). No patient experienced a thromboembolic event. CONCLUSIONS: PCNL is safe in patients continuing aspirin perioperatively and does not result in more blood transfusions, angioembolization procedures, or complications. Patients with large stone burdens who are at high risk for thromboembolic events appear to be able to safely undergo PCNL without discontinuing aspirin.

Effects of visceral fat area and other metabolic parameters on stone composition in patients undergoing percutaneous nephrolithotomy.

PURPOSE: Obesity is a risk factor for metabolic syndrome and urolithiasis, particularly uric acid stones. As estimated by visceral fat area, visceral obesity is a more specific measure of the risk of metabolic syndrome than body mass index. We investigated the effects of visceral fat area and other metabolic factors on uric acid stone formation in patients treated with percutaneous nephrolithotomy. MATERIALS AND METHODS: We retrospectively reviewed the records of 269 patients who underwent percutaneous nephrolithotomy. Visceral fat area was measured in each patient on a CT axial slice at the umbilical level using the Aquarius iNtuition fat analysis tool. Analysis was performed to determine the effect of visceral fat area and other comorbidities on uric acid stone formation. RESULTS: Of the 269 patients analyzed there was no difference in baseline comorbidities between uric acid and nonuric acid stone formers. Patients with uric acid stones had a significantly higher mean visceral fat area (209.3 vs 161.9 cm², p = 0.001), and rates of hypertension (67.4% vs 47.3%) and coronary artery disease (14.3% vs 4.6%, each p = 0.011). On logistic regression analysis hypertension (OR 2.16, 95% CI 1.05-4.45, p = 0.04) and a high visceral fat area (OR 3.64, 95% CI 1.22-10.85, p = 0.02) were independent risk factors for uric acid stones. CONCLUSIONS: As a marker of visceral obesity, visceral fat area contributes to the risk of metabolic syndrome and urolithiasis. Uric acid stone formers showed a significantly higher hypertension rate and mean visceral fat area, which were independent risk factors for uric acid urolithiasis. Evaluating these characteristics in stone formers may facilitate a tailored metabolic assessment and treatment plan.

"Extreme" renal preservation: neoadjuvant chemotherapy and percutaneous resection for upper-tract urothelial carcinoma in a patient with solitary kidney--a case report.

BACKGROUND AND PURPOSE: Renal preservation in selected patients with upper-tract urothelial cancer (UTUC) has been well described, offering an alternative to radical nephroureterectomy. We present our experiences in performing percutaneous treatments after neoadjuvant chemotherapy in one such patient with a large, complex, high-grade UTUC in a solitary kidney. CASE REPORT: A 55-year-old woman with a solitary kidney presented with a 5.2 cm enhancing mass with calcifications involving the left renal pelvis and lower pole. Cystoscopy and retrograde pyelography demonstrated normal bladder mucosa. Ureteroscopy revealed a large, papillary tumor occupying the renal pelvis. Ureteroscopic treatment was deemed impossible because of the lesion's volume. We proceeded with percutaneous resection after downsizing the tumor after a course of neoadjuvant chemotherapy. Using a 25F resectoscope via a percutaneous tract, resection was performed to fully excise the tumor, and the patient received two postoperative chemotherapy courses. A recurrence developed within an isolated calix 8 months postoperatively, which was also managed percutaneously. CONCLUSION: A multimodal approach in a highly motivated patient could represent a reasonable strategy for patients in whom such a therapy is desired.

Adjuncts to improve outcomes of shock wave lithotripsy.

Shock wave lithotripsy (SWL) has been a major tool in the treatment of urinary stones for nearly three decades. In recent years, SWL technology has been less effective at fragmenting stones than earlier devices; thus, adjunctive maneuvers to improve stone-free rates after SWL have been required. This article summarizes several of these adjuncts, such as slower shock wave rate, the use of percussion therapy to clear fragments, medications to hasten expulsion of fragments, and appropriate selection and positioning of patients for SWL.

Intravesical therapy for bladder cancer.

IMPORTANCE OF THE FIELD: Although transurethral resection of bladder tumor (TURBT) is effective therapy, up to 45% of patients will have a recurrence within 1 year after TURBT alone. Further, there is a 3 - 15% risk of tumor progression to muscle invasive and/or metastatic cancer. Depending on patient and tumor characteristics, a number of patients may benefit from some form of intravesical therapy. Adjuvant therapy is effective in avoiding post-TURBT implantation of tumor cells, eradicating residual disease, preventing tumor recurrence, and to delay or reduce tumor progression through direct cytoablation or immunostimulation. AREAS COVERED IN THIS REVIEW: The role of risk assessment in the management of nonmuscle invasive bladder cancer (NMIBC) and the indications for the use of intravesical agents are discussed. Findings from major randomized clinical trials on BCG, interferon and various chemotherapeutic agents are summarized; key aspects of drug pharmacology, drug efficacy, side effects, and toxicity are also covered. WHAT THE READER WILL GAIN: The reader will gain a basic understanding of the role of risk assessment in determining the need for intravesical therapy, as well as an overview of the different types of agents in use in the United States today. TAKE HOME MESSAGE: The type of intravesical therapy used is based on the risk groups as noted in the European prognostic tables. Bacillus Calmette-Guerin (BCG) is the most commonly used first-line agent immunotherapeutic agent for prophylaxis and treatment of carcinoma in situ and high-grade bladder cancer. Other immunotherapeutic options include the interferons, interleukins 2 and 12, and tumor necrosis factor, all of which have activity in BCG refractory patients, although with low durable remission rates. Studies have shown that chemotherapy prevents recurrence but not progression. The available data on intravesical chemotherapy do not indicate that any single agent currently in use is clearly better than any other. Therefore, the selection of a chemotherapeutic agent is usually based on cost, toxicity, and availability as well as on physician preference and experience.

Synchronous bilateral percutaneous nephrostolithotomy.

Various options are available for the treatment of patients with large, bilateral renal stones, including a staged percutaneous nephrostolithotomy (PCNL), synchronous PCNL with contralateral ureterorenoscopy, and synchronous bilateral PCNL. For patients with large bilateral renal stones, a synchronous bilateral PCNL may be offered if particular criteria are met. Overall outcomes reported for synchronous bilateral PCNL include high stone-free rates (95%-97%), low complication rates (9%-12%), short length of hospital stay (4-6 days), and low blood transfusion rates. Detailed cost analysis has revealed a significant cost advantage for synchronous vs staged bilateral PCNL; however, reimbursement practices reveal a significant financial disincentive for the surgeon to perform simultaneous bilateral PCNL. Here, we review the experience and current recommendations with synchronous bilateral PCNL for the treatment of patients with large, bilateral renal calculi.

Predicting differential renal function using computerized tomography measurements of renal parenchymal area.

PURPOSE: We evaluated any correlation between measured renal parenchymal area on computerized tomography and differential function on (99m)technetium-mercaptoacetyltriglycine renal scan to ascertain whether computerized tomography measurements could predict differential renal function. MATERIALS AND METHODS: Between 2005 and 2007 we identified 111 patients who underwent computerized tomography and renal scan. Average renal parenchymal thickness was calculated by measurements made at the upper and lower poles of each kidney. The product of average renal parenchymal thickness and renal length was calculated bilaterally and the ratio of parenchymal area was compared to the differential shown on renal scan. RESULTS: The average difference between predicted and observed renal function was 4.73% (Pearson's correlation coefficient 0.959). Patients with positive urine cultures at renal scan were compared to the other 89. The average functional difference was 6.54% vs 4.28% (Pearson's correlation 0.955 vs 0.965, p = 0.0045). The 89 uninfected patients were then compared based on contrast vs noncontrast computerized tomography and obstructed vs unobstructed renal units. No statistical difference was found with contrast administration. When compared based on evidence of obstruction, unobstructed kidneys resulted in a lower Pearson correlation (0.743 vs 0.975) but they had a statistically significant average functional difference in favor of unobstructed units (3.28% vs 5.10%, p = 0.0036). No difference was found in the obstructed group with prior drain placement. CONCLUSIONS: Differential renal parenchymal area measured by computerized tomography strongly correlates with differential function on renal scintigraphy and it may obviate the need for nuclear renal scan in some circumstances.