Roger L. Sur

A Prospective, Randomized, Double-Blinded Placebo-Controlled Comparison of Extended Release Oxybutynin Versus Phenazopyridine for the Management of Postoperative Ureteral Stent Discomfort

OBJECTIVES Ureteral stents commonly cause lower urinary tract and flank discomfort. We evaluated the use of extended release oxybutynin versus phenazopyridine versus placebo for the management of ureteral stent discomfort after ureteroscopy. METHODS Each of 60 patients who received a unilateral stent after ureteroscopy was given a blister pack containing 21 unmarked capsules of either extended release oxybutynin 10 mg, phenazopyridine 200 mg, or placebo in a prospective, randomized, and double-blinded fashion. Patients were instructed to take 1 capsule 3 times daily immediately after the procedure. Patients were given 50 tablets of oral narcotic to be taken as needed. Patients reported bothersome scores for flank pain, suprapubic pain, urinary frequency, urgency, dysuria, and hematuria on postoperative day 1, day 2, and the day of stent removal. Narcotic use was also recorded. RESULTS Eight patients were excluded from the analysis for stent migration necessitating early removal (1), uncontrollable pain (1), failure to complete blister pack (4), and inability to contact for follow-up surveys (2). There was no difference in bothersome score among the groups for flank pain, suprapubic pain, urinary frequency, urgency, and dysuria. The phenazopyridine group reported less hematuria on postoperative day 1 when compared with placebo, which was statistically significant. The oxybutynin group required fewer narcotics, but this finding was not statistically significant. CONCLUSIONS Although this study failed to show a significant difference in bothersome scores among the groups, the small sample size precludes definitive conclusion. Future studies pooling these data will determine the overall treatment effect and the optimal management of ureteral stent morbidity.

Silodosin to Facilitate Passage of Ureteral Stones: A Multi-institutional, Randomized, Double-blinded, Placebo-controlled Trial

BACKGROUND Using a selective α-blocker for medical expulsive therapy (MET) is a cost-effective treatment approach widely used for ureteral stones. OBJECTIVE To evaluate the efficacy of silodosin, a selective α-1a receptor antagonist, in this setting. DESIGN, SETTING, AND PARTICIPANTS This was a multicenter, phase 2 study conducted in adult patients with a unilateral ureteral calculus of 4-10mm. Of 239 patients in the safety population, six discontinued due to adverse events. INTERVENTION Patients were randomized 1:1 to receive silodosin 8 mg or placebo for up to 4 wk. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS The primary outcome was spontaneous stone passage, analyzed using logistic regression. Secondary outcomes included time to stone passage, emergency room (ER) visits, hospital admissions, analgesic use, and incidence and severity of pain. RESULTS AND LIMITATIONS No significant differences between the silodosin and placebo groups were observed for passage rate of all stones (52% vs 44%, respectively; p=0.2). However, silodosin achieved a significantly greater rate of distal ureter stone passage than placebo (p=0.01). Significant differences were not observed for ER visits, hospital admission, or use of analgesics. The number of patients in the intent-to-treat population was slightly below the calculated sample size (232 vs 240) and sample sizes were not calculated for subgroup analyses. CONCLUSIONS This is among the first prospective, randomized, multi-institutional trials to examine the efficacy of a selective α-1a antagonist as MET in patients with ureteral calculi and did not demonstrate a benefit to the entire ureter. However, silodosin was found to be well tolerated and beneficial in facilitating the passage of distal ureteral stones, warranting additional future studies on distal stone elimination. PATIENT SUMMARY In this report, we looked at the efficacy of silodosin for the treatment of ureteral stones. We found that silodosin increased passage of distal ureteral stones.

Trends in the surgical management of localized renal masses: thermal ablation, partial and radical nephrectomy in the USA, 1998-2008.

Treatment options for small renal masses include radical nephrectomy (RN), and nephron sparing modalities (NSM) such as partial nephrectomy (PN), and thermal ablation (Cryo‐ and radiofrequency ablation, C/RFA). Prior studies had demonstrated gross underutilization of PN; however overall treatment trends for C/RFA had not been well studied using a population‐based cohort. In this study, which examined management trends of localized renal masses in the USA, we identified an increased prevalence of RN, PN and C/RFA over the study period, with PN increasing the most rapidly, and with RN continuing to account for the vast majority of procedures. This is the first study to examine surgical management of renal masses in patients with non‐dialysis dependent chronic renal insufficiency. Although nephron sparing modalities were increasingly utilized over the study period, it is particularly concerning that patients with pre‐existing non‐dialysis dependent chronic renal insufficiency are receiving less nephron sparing approaches. Further investigations are required to confirm these findings and to identify impediments to the dissemination of nephron sparing modalities.

The Relationship of Obesity and Gender Prevalence Changes in United States Inpatient Nephrolithiasis

OBJECTIVE To review the Nationwide Inpatient Sample database to examine the relationships between obesity, gender, and nephrolithiasis. Recent reports indicate that the prevalence of nephrolithiasis has been increasing, especially among women. METHODS The Nationwide Inpatient Sample contains data on approximately 20% of hospital stays in the United States. Included in this analysis were discharges with primary diagnosis ICD-9 codes 592.0 (renal calculus) or 592.1 (ureteral calculus), from 1998 through 2003. All raw data were weighted to produce national estimates. Descriptive and inferential statistics were performed to determine changes in nephrolithiasis prevalence and associations of obesity and other comorbidities with nephrolithiasis. RESULTS We reviewed 181,092,957 hospital stays (weighted data). The prevalence of nephrolithiasis was relatively stable: 0.52% (149,302) in 1998 and 0.47% (147,541) in 2003. The prevalence of obesity increased from 3.06% (878,155) to 4.99% (1,575,247). The male:female ratio of patients with stones decreased from 1.6:1 to 1.2:1. Multivariate analysis revealed a statistically significant relationship (OR = 1.22, 95% CI 1.20-1.23, P <.001) between obesity and urinary stones. Obese females were more likely to develop stones than nonobese females (OR = 1.35, 95% CI 1.33-1.37, P <.001). The association between obesity and stones was weaker in males (OR = 1.04, 95% CI 1.02-1.06, P <.001). CONCLUSION In this sample of inpatients, obesity was associated with a significantly increased prevalence of urinary stones. This relationship was stronger in females than in males. Further studies are needed to determine whether weight reduction in obese patients affects urinary stone disease.

History of evidence-based medicine.

This essay reviews the historical circumstances surrounding the introduction and evolution of evidence-based medicine. Criticisms of the approach are also considered. Weaknesses of existing standards of clinical practice and efforts to bring more certainty to clinical decision making were the foundation for evidence-based medicine, which integrates epidemiology and medical research. Because of its utility in designing randomized clinical trials, assessing the quality of the literature, and applying medical research at the bedside, evidence-based medicine will continue to have a strong influence on everyday clinical practice.

A prospective, multi-institutional study of flexible ureteroscopy for proximal ureteral stones smaller than 2 cm

PURPOSE Flexible ureteroscopy is rapidly becoming a first line therapy for many patients with renal and ureteral stones. However, current understanding of treatment outcomes in patients with isolated proximal ureteral stones is limited. Therefore, we performed a prospective, multi-institutional study of ureteroscopic management of proximal ureteral stones smaller than 2 cm to better define clinical outcomes associated with this approach. MATERIALS AND METHODS Adult patients with proximal ureteral calculi smaller than 2 cm were prospectively identified. Patients with concomitant ipsilateral renal calculi or prior ureteral stenting were excluded from study. Flexible ureteroscopy, holmium laser lithotripsy and ureteral stent placement was performed. Ureteral access sheath use, laser settings and other details of perioperative and postoperative management were based on individual surgeon preference. Stone clearance was determined by the results of renal ultrasound and plain x-ray of the kidneys, ureters and bladder 4 to 6 weeks postoperatively. RESULTS Of 71 patients 44 (62%) were male and 27 (38%) were female. Mean age was 48.2 years. ASA(®) score was 1 in 12 cases (16%), 2 in 41 (58%), 3 in 16 (23%) and 4 in 2 (3%). Mean body mass index was 31.8 kg/m(2), mean stone size was 7.4 mm (range 5 to 15) and mean operative time was 60.3 minutes (range 15 to 148). Intraoperative complications occurred in 2 patients (2.8%), including mild ureteral trauma. Postoperative complications developed in 6 patients (8.7%), including urinary tract infection in 3, urinary retention in 2 and flash pulmonary edema in 1. The stone-free rate was 95% and for stones smaller than 1 cm it was 100%. CONCLUSIONS Flexible ureteroscopy is associated with excellent clinical outcomes and acceptable morbidity when applied to patients with proximal ureteral stones smaller than 2 cm.

The effect of restrictive bariatric surgery on urolithiasis.

BACKGROUND AND PURPOSE Roux-en-Y gastric bypass (RYGB) surgery, a mixed malabsorptive/restrictive procedure, is associated with enteric hyperoxaluria and an increased risk of kidney stones. The incidence of nephrolithiasis after purely restrictive bariatric procedures such as adjustable gastric banding or sleeve gastrectomy has not been well described. We aim to analyze the incidence of kidney stones in patients who undergo either adjustable gastric banding or sleeve gastrectomy. PATIENTS AND METHODS In a retrospective study, we analyzed a pool of 332 patients who underwent adjustable gastric banding and 85 patients who underwent sleeve gastrectomy at the University of California, San Diego Center for the Treatment for Obesity within a 54-month period (September 2006 to February 2011). The primary outcomes of urinary calculus diagnosis and surgical treatment were investigated using manual chart review and International Classification of Diseases and Related Health Problems-9 code electronic search. RESULTS Within the adjustable gastric banding cohort, we found a person-time incidence rate of 3.40 stone diagnoses per 1000 person-years. Within the sleeve gastrectomy cohort, we found a person-time incidence rate of 5.25 stone diagnoses per 1000 person-years. CONCLUSIONS Questions remain whether purely restrictive bariatric procedures such as sleeve gastrectomy or adjustable gastric banding avoid the risk of kidney stones. Our study demonstrates a very low incidence of kidney stones after restrictive bariatric procedures, although larger sample sizes, longer follow-up times, and controlled prospective studies are necessary to validate this finding.

Percutaneous Nephrolithotomy Use Is Increasing in the United States: An Analysis of Trends and Complications

PURPOSE To report the use and complication rates of percutaneous nephrolithotomy (PCNL) performed in the United States between 1998 and 2009. PATIENTS AND METHODS The Nationwide Inpatient Sample database was analyzed from 1998 to 2009 to identify all PCNL cases performed in adults ≥18 years old. Descriptive statistics were used for potential covariates: Demographics, comorbidities, academic/community hospital, rural/urban location, and U.S. geographic region. Common complications encoded by International Classification of Diseases-9 codes after PCNL were reported over time, and those found to be statistically significant were evaluated in the multivariate regression. Linear regression was used to analyze surgical trends. Multivariate regression was performed to identify covariates that predicted any surgical complication. RESULTS The use of PCNL among inpatients increased significantly from 15 to 27 surgeries/100,000 discharges between 1998 and 2009 (P<0.001), and this increase was seen in all geographic regions of the United States. The increase in adoption of PCNL was accompanied by an increase in complications (14% to 19%, P<0.001). Higher comorbidity (Charlson ≥3) was the strongest predictor of complications in multivariate analysis (odds ratio=2.22, P<0.001). CONCLUSIONS This is the first study to demonstrate an increase in PCNL use in the United States over the last decade. While there was an increase in surgical complications during this same period, the complication rate found reported is commensurate with other international reports. PCNL is safe and use of percutaneous surgery in the United States will most likely continue to increase.

Barriers to the Practice of Evidence-Based Urology

PURPOSE We investigated urologist perceptions of barriers to implementing evidence-based medicine in clinical practice. MATERIALS AND METHODS In April 2005 an Internet survey was conducted to assess American Urological Association member attitudes toward evidence-based medicine. This analysis presents the responses to an open-ended question about perceived barriers to implementing evidence-based clinical practice in urology. Two raters developed a coding scheme with 5 main categories of evidence concerns, system level factors, physician factors, patient factors and other barriers. Each rater independently assigned a category to each response. Discrepancies were resolved by consensus. RESULTS A total of 365 participants (72%) responded to the open-ended question, each providing up to 4 codable responses. Of the group 53% cited concerns about the evidence including the lack thereof, low quality, limited applicability and biased presentation. In addition, 37% reported system level factors such as issues of reimbursement, fear of litigation, problems with implementation, interference/bias by third parties, and expectations and attitudes of other providers as important issues. Physician factors and patient factors were further cited by 28% and 9%, respectively. In terms of the legitimacy of evidence-based medicine 9% expressed skepticism whereas 5% of respondents indicated that they saw no barriers to implementing evidence-based medicine in urology. CONCLUSIONS Efforts to promote evidence-based medicine in urology should focus not only on the generation of high quality clinical research but also on its unbiased reporting and timely dissemination. Concerted efforts should be made to reduce system level factors that hinder the implementation of evidence-based care.

Efficacy of intravesical ropivacaine injection on urinary symptoms following ureteral stenting: a randomized, controlled study.

PURPOSE Previous studies suggest that intravesical administration of nonsteroidal anti-inflammatory drugs may reduce the troublesome voiding symptoms and pain related to ureteral stenting. The objective of this study was to investigate the effectiveness of a long-acting local anesthetic, ropivacaine, injected submucosally into the bladder to control ureteral stent-associated symptoms. MATERIALS AND METHODS A randomized, single-blinded, study approved by our Institutional Review Board of adult patients scheduled for ureteroscopic stone surgery and possible stent placement was conducted. Patients were randomized to either the treatment cohort, who received five injections of 2 mL 0.5% ropivacaine around the ureteral orifice or to the control cohort, who received five injections of 2 mL of 0.9% normal saline in identical locations. Pain scale questionnaires were provided to each subject preoperatively and at postoperative hours 2, 4, 8, 24, and 48 as well as on the day of stent removal. Students t test and Wilcoxon signed rank sum tests were used for Gaussian and nonparametric data, respectively. RESULTS Twenty-two patients were randomized evenly into the two cohorts. The ropivacaine group consisted of 11 patients (eight men and three women) with a mean age of 56.2 years (standard deviation [SD] = 12, range 27-69), and the saline group consisted of eleven patients (six men and five women) with a mean age of 47.8 years (SD = 6.6, range 37-58). Intraoperative parameters appeared similar between the two cohorts. Intraoperative and postoperative narcotic usage was not different between the two groups, except at postoperative hour 2 when it favored the ropivacaine cohort (P = 0.05). Trends favoring ropivacaine in flank pain, bladder pain, genitalia pain, and hematuria domains were seen as long as 8 hours and up to the day of stent removal. Trends of less magnitude and duration were seen in the dysuria domain. No differences were seen in the frequency and urgency domains. CONCLUSIONS Our preliminary investigation with intravesical injection of ropivacaine before ureteroscopic surgery demonstrated trends toward decreased pain and voiding symptoms in this small-sample study. Inclusion of a larger sample should definitively address the effectiveness of intravesical ropivacaine and its impact on stent-related symptoms.