Robotic-assisted laparoscopic pyeloplasty for ureteropelvic junction obstruction A retrospective review of a high-volume Canadian center

INTRODUCTION

At present, there is no literature on the outcomes of robotic-assisted laparoscopic pyeloplasty (RALPyelo) in a Canadian context. Our objective was to perform a retrospective review of RALPyelo cases at a high-volume Canadian center.

METHODS

We performed a retrospective review of patients who underwent RALPyelo at St. Michael's Hospital, between January 2012 and May 2019. Demographics, operative details, and pre- and postoperative imaging results (ultrasounds, computed tomography [CT] scans, and diuretic renal scan [DRS ]) were recorded. Patients were excluded if at least one-year followup data was unavailable. Our primary outcome was clinical and radiologic improvement defined as 1) symptom improvement; 2) stable/improved split renal function on DRS ; and 3) either improvement in the degree of hydronephrosis on ultrasound or CT, or improved drainage time on DRS. Secondary outcomes included postoperative complications, need for diagnostic intervention, and reintervention for recurrent UPJO.

RESULTS

A total of 156 patients underwent RALPyelo after exclusions. The median age was 42 and 66% were female. Mean followup was 2.5 years. For our primary outcome, 87% had clinical and radiologic improvement. Diagnostic investigation for possible recurrent/persistent obstruction, based on symptoms and/or imaging results, was required in 17% of cases, but only 3% required reintervention for recurrent UPJO. Accordingly, the overall treatment success was 97%. The most common postoperative complication was urinary tract infection (18%), and urine leak was seen in only 2% of patients.

CONCLUSIONS

The results of our study compare favorably with currently reported outcomes in the literature and demonstrate the safety and high level of success of RALPyelo at a high-volume Canadian center.

Incidence and trends in the treatment of kidney stones in Canada: A population-based cohort study

INTRODUCTION

Our objective was to assess the incidence of kidney stones requiring acute care, trends in the surgical treatment of stones, and the demographics of stone formers in Canada.

METHODS

We conducted a population-based, retrospective cohort study using administrative data from the Canadian Institute for Health Information. We included Canadian residents age >18, outside of Quebec, who presented between January 1, 2013, and December 31, 2018, with a kidney stone episode. This was defined as a kidney stone resulting in hospital admission, emergency department visit, or stone intervention, specifically shockwave lithotripsy (SWL), ureteroscopy (URS), or percutaneous nephrolithotomy (PCNL).

RESULTS

There were 471 824 kidney stone episodes, including 184 373 interventions. The number of kidney stone episode increased from 277/100 000 in 2013 to 290/100 000 in 2018. The median age was 53 (interquartile range 41-65) and 59.9% were male. The crude rate for stone intervention was 877/100 000. The age- and gender-standardized rate for interventions was highest in Nova Scotia and Newfoundland and Labrador and lowest in Prince Edward Island. The most common intervention in Canada was URS (73.5%), followed by SWL (19.8%) and PCNL (6.7%). The percent utilization of SWL was highest in Manitoba, whereas for URS, it was highest in Prince Edward Island and Alberta.

CONCLUSIONS

Our study provides the first population-based data on the demographics of stone formers and treatment trends across Canada. There has been a 4.7% increase in kidney stone episodes over the study period. Those presenting to hospital or requiring intervention for a kidney stone are more likely to be male, age 41-65, and undergo URS.

An Updated Systematic Review and Meta-Analysis on the Technical, Oncologic, and Safety Outcomes of Microwave Ablation in Patients with Renal Cell Carcinoma

Introduction: Percutaneous microwave ablation (MWA) has emerged as a new energy modality for percutaneous renal tumor ablation with potential advantages over radiofrequency and cryoablation. The goal of our study was to determine MWA outcomes for suspicious renal masses, with a subset analysis for biopsy-proven renal cell carcinoma (RCC) and larger (T1b) tumors. Methods: Studies reporting outcomes of MWA for RCC were identified. Random-effects models with inverse-variance weighting were used to pool outcomes, including technical success rate (TSR), technical efficacy rate (TER), local recurrence rate (LRR), cancer-specific survival rate (CSSR), overall survival rate (OSR), and complications. Results: Among 914 studies captured, 27 studies with 1584 patients (1683 malignant renal tumors) were included. The pooled TSR and TER were 99.6% (95% confidence interval [CI], 98.0%-100%) and 96.2% (95% CI, 93.8%-98.2%). The pooled LRR was 3.2% (95% CI, 1.9%-4.7%). At 1, 3, and 5 years, the pooled CSSRs were 100% (95% CI, 99.4%-100%), 100% (95% CI, 98.4%-100%), and 97.7% (95% CI, 94.5%-99.7%), while pooled OSRs were 99.0% (95% CI, 97.5%-99.9%), 96.0% (95% CI, 93.1%-98.3%), and 88.1% (95% CI, 80.3%-94.2%). The pooled minor and major complication rates were 10.3% (95% CI, 7.1%-13.9%) and 1.0% (95% CI, 0.3%-2.1%). In 204 patients with 208 T1b tumors, the pooled TSR and TER were 100% (95% CI, 96.6%-100%) and 85.2% (95% CI, 71.0%-95.8%). The pooled LRR was 4.2% (95% CI, 0.9%-8.9%). At 1, 3, and 5 years, the pooled CSSRs were 98.2% (95% CI, 88.7%-100%), 97.2% (95% CI, 78.5%-100%), and 98.1% (95% CI, 72.3%-100%). At 1 and 3 years, the pooled OSRs were 94.3% (95% CI, 85.7%-99.6%) and 89.3% (95% CI, 68.7%-100%). The pooled minor and major complication rates were 14.8% (95% CI, 7.4%-23.8%) and 2.6% (95% CI, 0%-7.8%). Conclusions: MWA demonstrated favorable short- to intermediate-term oncologic outcomes with low complication rates, including in the T1b subset, with moderate quality of data and heterogeneity of assessed outcomes. This supports MWA as a safe and effective treatment for RCC and a potential viable option for larger tumors.

The Incidence and Risk Factors for Emergency Department Imaging in Acute Renal Colic

Objective: To determine the incidence of and risk factors for imaging in patients presenting to the emergency department (ED) with renal colic. Subject/Patients and Methods: We conducted a population-based cohort study in the province of Ontario, utilizing linked administrative health data. Patients who presented to an ED with renal colic between April 1, 2010, and June 30, 2020, were included. The rate of initial imaging (CT scans and ultrasound [U/S]) and repeat imaging within 30 days was determined. Generalized linear models were utilized to evaluate patient and institutional-level characteristics associated with imaging, and specifically CT vs U/S. Results: There were 397,491 index renal colic events, of which 67% underwent imaging (CT 68%, U/S 27%, and CT+U/S same day 5%). Repeat imaging was performed in 21% of events (U/S in 12.5%, CT in 8.4%) at a median of 10 days. Of those with an initial U/S, 28% had repeat imaging compared with 18.5% for those with an initial CT. Undergoing an initial CT was associated with being male, urban residence, later year of cohort entry, history of diabetes mellitus and inflammatory bowel disease, and presentation to nonacademic hospitals of larger size, or with a higher volume of ED visits. Conclusion: Two-thirds of renal colic patients underwent imaging, and CT was the most utilized modality. Patients undergoing an initial CT had a lower likelihood of repeat imaging within 30 days. The utilization of CT increased over time and was more common in males and those presenting to nonacademic hospitals of larger size, or with higher ED volumes. Our study highlights the patient- and institution-level factors that need to be targeted with prevention strategies to reduce the utilization of CT scans, when possible, for cost reduction and to minimize patient exposure to ionizing radiation.

A Population-Based Analysis of the Impact of the COVID-19 Pandemic on Solid Organ Transplantation in Ontario, Canada: Policy Response and Changes in Volume and 90-Day Outcomes

Objectives

To evaluate the impact of the COVID-19 pandemic on solid organ transplantation.

Background

COVID-19 caused unprecedented disruption to solid organ transplantation (kidney, liver, heart, lung). Concerns about safety and decreases in deceased donors due to pandemic lockdowns have been described as potential causes.

Methods

We report population-based rates of transplantation during the first 3 waves of COVID-19 in Ontario, Canada (March 1, 2020-July 3, 2021) versus a pre-COVID-19 baseline period (January 1, 2017-February 29, 2020). Poisson models were used to predict transplantation rates during COVID-19, based on pre-COVID-19 rates, and generate observed to expected rate ratios (RRs). Ninety-day transplant outcomes (mortality, retransplantation, transplant nephrectomy) were captured.

Results

A 34.4% decrease (RR, 0.656; 95% confidence interval [CI], 0.586-0.734) in transplant rates was observed, coinciding with wave 1 and the deployment of a provincial transplant triaging system. Transplants decreased by 14.6% in wave 2 (RR, 0.854; 95% CI, 0.770-0.947) and 23.1% in wave 3 (RR, 0.769; 95% CI, 0.690-0.857) despite the triaging system not being activated. Overall, there was a 24.3% decrease (RR, 0.757; 95% CI, 0.679-0.844) in transplant rates, equivalent to 409 fewer transplants. No sustained changes were observed in heart or liver but sustained and large decreases were seen for lung (RR, 0.664; 95% CI, 0.482-0.915) and kidney (RR, 0.721; 95% CI, 0.602-0.863) transplantation. A low prevalence (1.7%) of COVID-19 infection within 90 days of transplantation was seen. No differences were observed in other 90-day outcomes.

Conclusions

Early safety concerns limited transplantation to immediate life-saving procedures; however, the reductions in kidney and lung transplants continued for the rest of the pandemic, where no restrictions were in place.

Surgical Outcomes between Routes of Hysterectomy in Patients with a Previous Cesarean Section

STUDY OBJECTIVE

To determine the difference in surgical complications for patients with a previous cesarean section (CS) undergoing abdominal, vaginal, or laparoscopic hysterectomy.

DESIGN

A population-based retrospective cohort study.

SETTING

Province of Ontario, Canada.

PATIENTS

10 300 patients with at least 1 CS between July 1, 1991, and February 17, 2018.

INTERVENTIONS

Benign, nongravid hysterectomy between Apr 1, 2002, and March 31, 2018.

MEASUREMENTS AND MAIN RESULTS

The primary outcome was a composite of all surgical complications within 30 days of surgery. Secondary outcomes were rate of genitourinary complications, readmission to hospital, and emergency department visit occurring within 30 days of surgery. Of 10 300 patients who had at least one previous CS, who underwent subsequent hysterectomy for a benign indication, 7370 underwent an abdominal hysterectomy (71.55%), 813 (7.9%) had a vaginal hysterectomy, and 2117 (20.55%) underwent a laparoscopic hysterectomy. The adjusted odds of any surgical complication from hysterectomy was significantly lower when performed by the vaginal approach than the laparoscopic approach (odds ratio, 0.32; 95% confidence interval, 0.20-0.51; p <.0001). There was no difference in the odds of surgical complication between abdominal and laparoscopic approaches (odds ratio, 1.09; 95% confidence interval, 0.87-1.37; p = .45).

CONCLUSION

Our retrospective population-based study demonstrates that, after previous CS, patients selected to undergo vaginal hysterectomy experienced lower risk than either abdominal or laparoscopic approaches. This suggests that CS alone should not be a contraindication to vaginal hysterectomy.

Determination of optimal stent length: a survey of urologic surgeons

Introduction

Ureteral double-J stent length is an important factor affecting stent-related symptoms. Multiple techniques exist to determine ideal stent length for a given patient, however, little is known about what techniques urologists rely on. Our objective was to identify how urologists determine optimal stent length.

Material and methods

An online survey was e-mailed in 2019 to all members of the Endourology Society. The survey sought to assess what methods are commonly used to determine choice of stent length, along with frequency of stent placement post ureteroscopy, duration of stenting, availability of different stent lengths and the use of stent tether.

Results

301 urologists (15.1%) responded to our survey. Following ureteroscopy, 84.5% of respondents would stent at least 50% of the time. Following uncomplicated ureteroscopy, most respondents (52.0%) would leave a stent for 2-7 days. Patient height was most commonly ranked first as the method of choice in determining stent length (47.0%), followed by estimation based on experience only (20.6%) and intra-operative direct measurement of ureteric length (19.1%). Most respondents utilized multiple methods in determination of optimal stent length. Most respondents (66.5%) were interested in a simple intra-operative technique utilizing a special ureteral catheter that would help choose the most appropriate stent length.

Conclusions

Post-ureteroscopy stent insertion is common and patient height is the most common method of choice used in determining optimal stent length. Most respondents were interested in using a simple, novel ureteral catheter device that would allow them to more accurately select optimal stent length.

Infection complications after transrectal ultrasound-guided prostate biopsy: A radiology department's experience and strategy for improvement

INTRODUCTION

Transrectal ultrasound (TRUS)-guided prostate biopsy is a common procedure performed to diagnose prostate cancer. The risk of infection complications is well-described in the literature, and strategies to avoid such complications continue to evolve over time. We performed a retrospective review of our infection complications and propose a strategy for improvement.

METHODS

We reviewed clinical outcomes from patients undergoing TRUS-guided prostate biopsy at our institution from November 2018 to November 2020. We reported the antimicrobial prophylaxis received, whether the biopsy was systematic or targeted, and we examined the rate of clinically significant infection complications and hospitalization.

RESULTS

Among 312 men who underwent TRUS-guided prostate biopsy during the study period, seven (2.2%) had an infection. Four patient groups with distinct antimicrobial regimen were identified; the largest of these patient groups received a three-day course of cefixime and a single dose of fosfomycin (59%). The proportion of patients with infection complications across these groups did not demonstrate a statistically significant difference (p=0.803). There was no significant difference in proportion of infection between systematic and targeted biopsy groups (3.0% vs. 0%, p=0.204). The proportion of patients hospitalized was 1.3%, with a mean length of stay of four days.

CONCLUSIONS

We report a rate of clinically significant infection following TRUS-guided prostate biopsy of 2.2%. Due to our referral pathway, we have an inconsistent approach to antimicrobial prophylaxis, although there was no statistically significant difference in infection rate between the groups. We propose a standardized approach that may lead to improved patient outcomes.

A high-fidelity, virtual reality, transurethral resection of bladder tumor simulator: Validation as a tool for training

INTRODUCTION

Simulation-based training is used to help trainees learn surgical procedures in a safe environment. The objective of our study was to test the face, content, and construct validity of the transurethral resection of bladder tumor (TURBT) module built on the Simbionix TURP Mentor simulator.

METHODS

Participants performed five standardized cases on the simulator. Domains of the simulator were evaluated on a five-point Likert scale to establish face and content validity. Construct validity was assessed through the simulator's built-in scoring metrics, as well as video recordings of the simulator screen and an anonymized view of participants' hands and feet, which were evaluated using an objective structured assessment of technical skills (OSATS) tool.

RESULTS

Ten experienced operators and 15 novices participated. Face validity was somewhat acceptable (mean realism 3.8/5±1.03 standard deviation [SD]; mean appearance 4.1/5±0.57), as was content validity, represented by simulation of key steps (mean 3.9±0.57). The simulator failed to achieve construct validity. There was no difference in mean simulator scores or OSATS scoring between experienced operators and novices. Novices significantly improved their mean simulator scores (305.9 vs. 332.4, p=0.006) and OSATS scoring (15.8 vs. 18.1, p=0.001), while 87% felt their confidence to perform TURBT improved. Overall, 92% of participants agreed that the simulator should be incorporated into residency training.

CONCLUSIONS

Our study suggests a role for the TURBT module of the Simbionix TURP Mentor simulator as an introduction to TURBT for urology trainees. Strong support was found from both experienced operators and novices for its formal inclusion in resident education.

Systematic Review of the Prevalence of Kidney Stones in Cystic Fibrosis

Purpose: To investigate the prevalence of urolithiasis in cystic fibrosis (CF) and to summarize the available clinical features within this unique population. Methods: Studies reporting the prevalence of urolithiasis in CF patients were identified by a systematic search of the literature from inception to July 31, 2020 on three databases: Ovid Medline, Ovid Embase, and Web of Science. Data were extracted on a predetermined standardized form by two independent authors. Results: A total of 596 publications were retrieved and screened, 15 of which met the eligibility criteria. The publications were published between 1993 and 2019 and were all observational in design. There was a total of 2982 patients with CF included in this review. The overall prevalence of stone formation in the CF population was 4.6% (137/2982). The mean age of diagnosis was 25.1 ± 9.6 and ranged from 0.25 to 47. Ultrasound was the most common imaging modality for kidney stone diagnosis. There was no apparent sex difference, with a female to male ratio of 1:1. Surgical intervention was required in 37.8% (34/90) of cases. Stone recurrence was reported in 42.9% (33/77) of stone formers. Conclusions: This review provides the most recent update for the prevalence of urolithiasis in CF patients and summarizes the available clinical data. Our findings suggest that patients with CF could be at risk for developing stones at a younger age and require interventional management strategies at higher rates compared with the general population. Given the heterogeneity of the literature for urolithiasis in CF, larger population-based studies reporting the epidemiology, clinical features, and management strategies are required to further our understanding of urolithiasis in CF.

Endoscopic ultrasound-guided trans-duodenal fine-needle biopsy of a small renal mass: case report and review of the literature

Background

The incidental detection of small renal masses (SRMs) is increasing and biopsy to obtain pathological diagnosis is increasingly proposed as a diagnostic tool to guide further management. Renal mass biopsies are traditionally performed via a percutaneous approach. However, this is not always feasible due to anatomical limitations. A rarely reported alternative biopsy approach for SRMs is endoscopic ultrasound (EUS)-guided fine-needle biopsy (FNB). Herein, we describe a case of EUS-guided trans-duodenal FNB for a SRM that was not amenable to standard percutaneous biopsy.

Case presentation

A 48-year-old man was incidentally found to have a right-sided SRM measuring 2.9 × 2.2 × 2.4 cm during evaluation for a hernia. It was anterior, interpolar, completely endophytic and near the renal hilum. The tumor was not amenable to traditional percutaneous biopsy due to its anterior location. However, the renal mass was in close proximity to the descending duodenum and so it was felt that an EUS-guided trans-duodenal FNB would be feasible. The procedure was successful without any complications. The specimen adequacy was satisfactory for evaluation and consistent with renal papillary carcinoma with WHO/ISUP grade 3 nuclear changes.

Conclusion

Our case report demonstrated that EUS-guided trans-duodenal FNB was a safe and feasible approach to obtaining biopsy tissue diagnosis of a SRM that was not amenable to percutaneous biopsy.

Do 5-alpha reductase inhibitors decrease the risk of recurrent gross hematuria in patients who have had a transurethral prostatectomy?

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Clips Can be Safely Used for Vascular Control of the Renal Vessels During Laparoscopic Donor Nephrectomy

OBJECTIVE

To review our experience using clips to control the renal vessels during laparoscopic donor nephrectomy (LDN) and determine the safety of this practice.

METHODS

We performed a retrospective review of patients who underwent LDN at our centre January 1, 2007-September 17, 2019. The primary outcome was the rate of complication associated with vascular control of the renal vessels, which included (1) conversion to open to manage bleeding, (2) additional procedures for bleeding, and (3) major bleeding requiring blood transfusion. Secondary outcomes included the rate of renal artery/vein clip dislodgement or crossing, change in hemoglobin, warm ischemia time and the incidence of intra-operative complications and postoperative in-hospital complications.

RESULTS

We included 503 patients who underwent LDN, of which 497 were left sided. The main renal artery was controlled with 3 titanium clips in 489 (97%) cases. The main renal vein was controlled with 2 polymer-locking clips in 478 (95%) cases. For our primary outcome, there were no conversions to open to manage bleeding, no secondary procedures due to bleeding and no major bleeding requiring blood transfusion. Additionally, there were no donor deaths. Regarding our secondary outcomes, there were 5 intraoperative events related to the titanium clips being placed on the renal artery and 1 intraoperative event related to the polymer-locking clips on the renal vein, none of which resulted in any morbidity.

CONCLUSION

Using 3 titanium clips on the renal artery and 2 polymer-locking clips on the renal vein during left LDN is safe and provides excellent vascular control.

Urological issues in pregnancy: A review for urologists

Urological issues in the pregnant patient present a unique clinical dilemma. These patients may be challenging to treat due to risks associated with medications and surgical procedures. This review aims to provide an update on the physiological changes and surgical risks in pregnancy. In addition, we review the approach for management of urolithiasis and urinary tract infections in pregnancy. Lastly, we highlight the importance of a multidisciplinary approach to placenta percreta, a condition not commonly addressed in urological education.

Assessing the Necessity of Routine Crossmatching for Blood Transfusion in Renal Transplantation

INTRODUCTION

Routine crossmatch of packed red blood cells (pRBCs) is completed preoperatively at many centers despite conflicting evidence on the incidence of blood transfusions with renal transplantation. In the current economic climate, resource adjudication should be judicious and medically appropriate. The objective of this study was to determine the incidence, timing, and predictors of early postoperative pRBC transfusion in patients undergoing renal transplantation.

METHODS

A retrospective review of all patients undergoing renal transplantation at our institution from January 2013 to May 2016 was performed. Demographic, biochemical, and clinical parameters were recorded. The primary outcome was early postoperative transfusion, defined as an intraoperative transfusion or within 2 days of surgery. Multivariable logistic regression was performed to identify associations with early postoperative transfusion.

RESULTS

We identified 428 patients during the study period (average age 55 years, 60% male, 30% obese, 67% deceased donor, and 43% preoperative antithrombotic use). Forty (9.3%) patients required early postoperative transfusion (mean: 2.8 pRBCs/transfusion) and most did not require blood urgently. Only 20 (4.7%) patients required a transfusion intraoperatively or on the same day of surgery. Lower preoperative hemoglobin (per g/L unit: odds ratio [OR]: 0.943), female gender (OR: 2.752), and preoperative antithrombotic use (OR 2.369) were associated with a need for early postoperative transfusion.

CONCLUSION

Transfusion in the early postoperative period following renal transplantation was less than 10%, suggesting that routine crossmatch may not be necessary for all patients. Preoperative hemoglobin, female gender, and preoperative antithrombotic use were associated with increased risk and may be useful to risk-stratify patients who require crossmatch.

Photoacoustic imaging of kidney fibrosis for assessing pretransplant organ quality

Roughly 10% of the world's population has chronic kidney disease (CKD). In its advanced stages, CKD greatly increases the risk of hospitalization and death. Although kidney transplantation has revolutionized the care of advanced CKD, clinicians have limited ways of assessing donor kidney quality. Thus, optimal donor kidney-recipient matching cannot be performed, meaning that some patients receive damaged kidneys that function poorly. Fibrosis is a form of chronic damage often present in donor kidneys, and it is an important predictor of future renal function. Currently, no safe, easy-to-perform technique exists that accurately quantifies renal fibrosis. We describe a potentially novel photoacoustic (PA) imaging technique that directly images collagen, the principal component of fibrotic tissue. PA imaging noninvasively quantifies whole kidney fibrotic burden in mice, and cortical fibrosis in pig and human kidneys, with outstanding accuracy and speed. Remarkably, 3-dimensional PA imaging exhibited sufficiently high resolution to capture intrarenal variations in collagen content. We further show that PA imaging can be performed in a setting that mimics human kidney transplantation, suggesting the potential for rapid clinical translation. Taken together, our data suggest that PA collagen imaging is a major advance in fibrosis quantification that could have widespread preclinical and clinical impact.

Objective Assessment and Standard Setting for Basic Flexible Ureterorenoscopy Skills Among Urology Trainees Using Simulation-Based Methods

Objective: To objectively assess the performance of graduating urology residents performing flexible ureterorenoscopy (fURS) using a simulation-based model and to set an entrustability standard or benchmark for use across the educational spectrum. Methods: Chief urology residents and attending endourologists performed a standardized fURS task (ureterorenoscopy and repositioning of stones) using a Boston Scientific^© Lithovue ureteroscope on a Cook Medical^© URS model. All performances were video-recorded and blindly scored by both endourology experts and crowd-workers (C-SATS) using the Ureteroscopic Global Rating Scale, plus an overall entrustability score. Validity evidence supporting the scores was collected and categorized. The Borderline Group (BG) method was used to set absolute performance standards for the expert and crowdsourced ratings. Results: A total of 44 participants (40 chief residents, 4 faculties) completed testing. Eighty-three percent of participants had performed >50 fURS cases at the time of the study. Only 47.7% (mean score 12.6/20) and 61.4% (mean score 12.4/20) of participants were deemed "entrustable" by experts and crowd-workers, respectively. The BG method produced entrustability benchmarks of 11.8/20 for experts and 11.4/20 for crowd-worker ratings, resulting in pass rates of 56.9% and 61.4%. Conclusion: Using absolute standard setting methods, benchmark scores were set to identify trainees who could safely carry out fURS in the simulated setting. Only 60% of residents in our cohort were rated as entrustable. These findings support the use of benchmarks to earlier identify trainees requiring remediation.

Peritoneal dialysis catheter removal at the time of renal transplantation: Choosing the optimal candidate

INTRODUCTION

Concurrent peritoneal dialysis (PD) catheter removal during renal transplantation is controversial, with limited evidence supporting this practice. Our objective was to determine the rate of delayed graft function (DGF) in patients on preoperative PD. Additionally, we sought to identify which patients can safely have their PD catheter removed during transplantation due to a low risk of DGF.

METHODS

We conducted a retrospective observational study between June 2011 and December 2015. The primary outcome was the diagnosis of DGF, defined as the need for dialysis within the first week of transplantation. Clinical and transplant factors, including graft type and donor criteria, were assessed for association with the primary outcome. Catheter-related complication rates were also compared between post-transplant PD and hemodialysis (HD).

RESULTS

Of our cohort of 567 patients, 145 patients (25.6%) developed DGF. Obesity (odds ratio [OR] 1.06; 95% confidence interval [CI] 1.00-1.11; p=0.04) and increased perioperative blood loss (OR 1.002; 95% CI 1.000-1.003; p=0.03) were predictors of DGF. Protective factors included living donor (LD) grafts (OR 0.15; 95% CI 0.05-0.49; p=0.002) and intraoperative graft urine production (OR 0.39; 95% CI 0.23-0.65; p<0.001). In our PD cohort, only LD grafts demonstrated lower DGF rates (0 LD vs. 20.8% deceased donor; p=0.003). In terms of post-transplant renal replacement therapy, patients on PD and HD had similar duration of temporary dialysis (one day PD vs. two days HD; p=0.48) and catheter-related complication rates (4.5% PD vs. 2.6% HD; p=0.30).

CONCLUSIONS

Carefully selected patients, such as those receiving LD grafts, may benefit from concurrent PD catheter removal.

Population-based assessment of re-treatment and healthcare utilisation after photoselective vaporisation of the prostate or electrosurgical transurethral resection of the prostate

OBJECTIVE

To compare the healthcare utilisation and repeat surgical treatment rate amongst older men undergoing an electrosurgical-transurethral resection of the prostate (TURP) vs photoselective vaporisation of the prostate (PVP), as the real-world implementation and outcomes of laser-based treatment have not been well studied.

PATIENTS AND METHODS

We used administrative data from the province of Ontario, Canada, to identify all men aged >66 years who underwent their first electrosurgical-TURP/PVP between 2003 and 2016. Our primary exposure was type of procedure (PVP or electrosurgical-TURP). Our primary outcome was need for repeat surgical treatment. The primary analysis was an adjusted marginal Cox model approach, which accounted for clustering of patients within surgeons; adjusted hazard ratios (aHRs) or odds ratios (aORs) and 95% confidence intervals (CIs) are reported.

RESULTS

We identified 52 748 men: 6838 (13%) underwent PVP, and 45 910 (87%) underwent electrosurgical-TURP. The median age was similar, and PVP became more common with time. Compared to the PVP group, more patients in the electrosurgical-TURP group had prior gross haematuria or urinary retention, and fewer had used anticoagulants, α-blockers, or 5α-reductase inhibitors. The need for repeat surgical treatment was significantly higher amongst men who had PVP (aHR 1.57, 95% CI 1.38-1.78; absolute risk difference +2.3%). PVP was also associated with a slightly higher risk of return to the emergency room within 30 days (aOR 1.11, 95% CI 1.01-1.22) and a significantly lower risk of blood transfusion (aOR 0.24, CI 0.16-0.37); the majority of PVP cases were done with a <24 h stay (73%) vs electrosurgical-TURP (7%).

CONCLUSIONS

While some of the expected benefits of PVP (such as reduced transfusion risk and shorter length of stay) were observed, the significantly higher rate of repeat surgical treatment compared to electrosurgical-TURP may represent an important difference in implementation of this technology outside of clinical trials.

The Utilization of Benign Prostatic Hyperplasia and Bladder-Related Medications After a Transurethral Prostatectomy

OBJECTIVE

To determine how often prostate- and bladder-specific medications for lower urinary tract symptoms are used following a transurethral prostatectomy (TURP).

METHODS

This study utilized several linked, routinely collected datasets from the province of Ontario, Canada to identify men older than 66 years who underwent their first TURP between April 2003 and March 2016. The primary outcome was the probability of using at least 30 days of either prostate-specific alpha blockers (AB), 5-alpha reductase inhibitors (5ARI), or anticholinergics/beta-3 agonists (AC/B3) after their TURP.

RESULTS

We identified 58,038 men (median age 75), with a median follow-up of 4.9 years. In the 6 months prior to their TURP, AB, 5ARIs or AC/B3 were used by 62%, 32%, and 6%, respectively. Following a 90-day washout period after TURP, these medications were used by 27%, 20%, and 15% of men, respectively. The cumulative probability of using these medications within the first 10 years after TURP was 38%, 28%, and 20%, respectively. Family physicians prescribed the majority of AB, while urologists prescribed the majority of the AC/B3. Among men on AC/B3 prior to TURP, 46% used them after TURP; in multivariate cox regression analysis age ≥75, diabetes, preoperative use of AC/B3, and no preoperative urinary retention predicted postoperative utilization of AC/B3 medications.

CONCLUSION

There is considerable use of AB and 5ARIs despite a lack of evidence for using these medications after a TURP. Given the well-characterized placebo response in BPH patients, this practice should be properly evaluated for clinical efficacy.

Routine Preoperative Electrocardiograms in Patients at Low Risk for Cardiac Complications During Shockwave Lithotripsy: Are They Useful?

INTRODUCTION

Routine preoperative electrocardiogram (ECG) before shockwave lithotripsy (SWL) is frequently performed despite recommendations against its use in asymptomatic patients undergoing low-risk surgical procedures. This study assesses whether routine preoperative ECG before SWL is useful in patients at low risk for cardiac complications.

MATERIALS AND METHODS

A retrospective study of SWL at our center (2003-2013) reviewed all cardiac-related preoperative cancellations, intraoperative complications, postoperative admissions, and emergency department presentations in patients at low risk for cardiac complications. Patients received SWL with sedation and continuous five-lead ECG monitoring.

RESULTS

Of 30,892 referrals, preoperative ECG triggered 13 (0.04%) cancelations in low-risk patients (1 with new atrial fibrillation and 12 with ischemia/previous infarction). Of these patients, 1 had a subsequent abnormal cardiac work-up and 11 underwent uncomplicated SWL without cardiac intervention (2 had unknown history). Of 27,722 treatments, 5 (0.02%) were stopped prematurely in low-risk patients because of arrhythmia (3 had normal preoperative ECG, 1 had abnormal ECG, and 1 did not complete ECG). Three patients developed an arrhythmia with sedation and 2 patients were admitted postoperatively because of cardiac complications (1 for atrial fibrillation and 1 for hypertension), of whom all had normal preoperative ECG. No patients presented to our emergency department with cardiac complications after SWL.

CONCLUSIONS

In patients at low risk for cardiac complications, preoperative ECG triggered very few cancellations and did not predict early termination of treatment or cardiac complications after SWL. These findings suggest that in low-risk patients, routine preoperative ECG has little effect on treatment or complication rate and should be omitted.

Is extracorporeal shockwave lithotripsy a risk factor for the development of diabetes mellitus? A population-based study

OBJECTIVE

To determine if patients treated with extracorporeal shockwave lithotripsy (ESWL) are at a greater risk of developing diabetes mellitus (DM) than those treated with ureteroscopy (URS).

PATIENTS AND METHODS

A retrospective population-based cohort study was performed of all ESWL and URS stone treatments done in Ontario between January 1994 and March 2014, utilising linked encoded healthcare databases. The primary outcome was the development of DM >90 days after treatment. The Kaplan-Meier method was used for unadjusted survival analysis and multivariable analysis with Cox proportional hazards regression was used to assess the risk of DM between the ESWL and URS groups whilst controlling for age, gender, region of residence, income quintile, year of treatment, and comorbidity index. A sensitivity analysis with a subset of ESWL patients treated for left renal or proximal ureteric stones was completed.

RESULTS

We identified 106 963 patients who underwent ESWL or URS over the study period with a median follow-up of 6.6 years (ESWL 8.5 years, URS 5.6 years). Unadjusted survival analysis showed an increased risk of developing DM in the ESWL group compared to the URS group (P < 0.001); however, multivariable analysis showed no increased risk of DM in the ESWL cohort (hazard ratio [HR] 0.97, 95% confidence interval [CI] 0.91-1.02; P = 0.25). Similarly, sensitivity analysis showed no increased risk of DM in the left renal/proximal ureteric stone ESWL cohort compared to the URS cohort (HR 1.04, 95% CI 0.96-1.13; P = 0.35).

CONCLUSIONS

Our population-based cohort study demonstrated no increased risk of DM in patients undergoing ESWL compared to URS.

Impact of Resident Overnight Duty Hour Changes on Obstetrical Outcomes: A Population-Based Cohort Study

OBJECTIVE

To determine whether obstetrical patient outcomes have changed following the introduction of restricted resident work hours.

METHODS

A population-based retrospective cohort study of the effects of restricted duty hours for residents in July 2013 at three academic hospitals in Toronto, ON using linked health care databases. The study included 6763 deliveries in the 2 years pre-exposure and 5548 deliveries in the 2 years post-exposure.

RESULTS

The primary outcome, planned prior to data collection, was a composite index of 29 maternal/fetal outcomes including maternal transfusion/postpartum hemorrhage, maternal infection, fetal mortality, NICU admissions, and surgical/obstetrical complications. There were seven secondary outcomes analysed: NICU admissions; neonatal death; maternal transfusion or postpartum hemorrhage; maternal infection; and three composite measures. A generalized estimating equation model, clustered by institution, was utilized to assess for differences post-intervention. We found no significant differences in baseline demographics between groups. After the implementation of duty hour restrictions, no significant difference was seen in the primary outcome. However, an increased incidence of composite maternal surgical/obstetrical outcomes (OR 1.191; 95% CI 1.037-1.367, P = 0.013) and transfusion/postpartum hemorrhage (OR 1.232; 95% CI 1.074-1.413, P = 0.003) was found. There were no significant differences in other secondary outcomes.

CONCLUSION

Since the implementation of resident duty hour restrictions, there was no overall change in patient outcomes. However, there was an increase in surgical/obstetrical complications and transfusion/postpartum hemorrhage. This suggests that duty hour restrictions may not be beneficial to patient outcomes. It highlights the need to further investigate the clinical impact of a change in resident duty hours.

Dual usage of a stone basket: Stone capture and retropulsion prevention

INTRODUCTION

Stone migration during ureteroscopy (URS) for proximal ureteric calculi is a constant challenge. Several retropulsion prevention devices have been developed to optimize URS outcomes. Our technique involves capturing the stone within a four-wire Nitinol stone basket and then performing laser lithotripsy to dust the stone while it is engaged in the basket. The dusted fragments wash out with the irrigation fluid and once small enough, the remaining stone is removed intact.

METHODS

A retrospective chart review was performed of all proximal semi-rigid URS procedures for a solitary calculus (2000-2016). We compared our new technique introduced in 2010 to URS control procedures that did not use retropulsion prevention techniques or devices.

RESULTS

One hundred and forty patients underwent URS for proximal ureteric calculi. Mean stone diameter was 9.3±3.4 mm, with similar impaction rate between both groups (44.1% vs. 43.1% control; p=n/s). The mean surgical procedure time was 53.3±17.9 minutes for the new technique and 65.2±29.2 minutes for the control group (p=0.005). Compared to the new technique, the control group had a higher rate of retropulsion (33.3% vs. 14.7%; p=0.01) and required flexible URS more often to exclude or remove residual fragments (24.1% vs. 59.1%; p=0.001). Using the new technique, stone-free rates were higher (79.1% vs. 69.4%; p=n/s) and there was a lower likelihood of leaving residual fragments both <3 mm and ≥3 mm (p=0.001).

CONCLUSIONS

Our novel technique results in shorter operative times, lower retropulsion rates, and decreases postoperative residual stone fragments.

Simulation-Based Laparoscopic Surgery Crisis Resource Management Training-Predicting Technical and Nontechnical Skills

OBJECTIVES

To develop a unique simulation-based assessment using a laparoscopic inferior vena cava (IVC) injury scenario that allows for the safe assessment of urology resident's technical and nontechnical skills, and investigate the effect of personality traits performance in a surgical crisis.

METHODS

Urology residents from our institution were recruited to participate in a simulation-based training laparoscopic nephrectomy exercise. Residents completed demographic and multidimensional personality questionnaires and were instructed to play the role of staff urologist. A vasovagal response to pneumoperitoneum and an IVC injury event were scripted into the scenario. Technical and nontechnical skills were assessed by expert laparoscopic surgeons using validated tools (task checklist, GOALS, and NOTSS).

RESULTS

Ten junior and five senior urology residents participated. Five residents were unable to complete the exercise safely. Senior residents outperformed juniors on technical (checklist score 15.1 vs 9.9, p < 0.01, GOALS score 18.0 vs 13.3, p < 0.01) and nontechnical performance (NOTSS score 13.8 vs 10.1, p = 0.03). Technical performance scores correlated with NOTSS scores (p < 0.01) and pass/fail rating correlated with technical performance (p < 0.01 for both checklist and GOALS), NOTSS score (p = 0.02), and blood loss (p < 0.01). Only the conscientiousness dimension of the big five inventory correlated with technical score (p = 0.03) and pass/fail rating (p = 0.04).

CONCLUSIONS

Resident level of training and laparoscopic experience correlated with technical performance during a simulation-based laparoscopic IVC injury crisis management scenario, as well as multiple domains of nontechnical performance. Personality traits of our surgical residents are similar and did not predict technical skill.

A survey of Canadian renal transplant surgeons: Use of ureteric stents and technique of the ureteroneocystotomy

INTRODUCTION

The role of ureteric stenting in renal transplant has been well-demonstrated. The goal of this survey was to determine the utilization of ureteric stents by Canadian transplant surgeons, and how the ureteroneocystotomy and followup is performed.

METHODS

An online survey was sent to the 40 surgeon members of the Canadian Society of Transplantation. The primary outcome was the rate of ureteric stent use at the time of renal transplantation. The secondary outcomes were the ureteric stent dwell time, use and type of prophylactic antibiotics, and the use of routine post-transplant ultrasonography.

RESULTS

All respondents (25) used ureteric stent routinely and 92% remove the stent between four and six weeks postoperatively. Prophylactic antibiotics were used 64% of the time for ureteric stent removal. The majority of surgeons do not routinely perform a post-stent removal ultrasound. Fifty-six percent of respondents perform a refluxing anastomosis.

CONCLUSIONS

Ureteric stents are routinely used in renal transplant in Canada. Areas for improvement and topics of debate identified from this survey are the need for peri-stent removal antibiotics, the role of post-stent removal ultrasound, the duration of stent dwell time, and the need for a non-refluxing ureteroneocystotomy.

Robotic Autotransplantation and Management of Post-transplant Anastomotic Strictures: the Future Is Here

PURPOSE OF REVIEW

We set out to review the current published experience with robotic autotransplantation. Although the experience to date is limited, this surgery appears to be safe and technically feasible. We also examined the use of the robotic surgical platform for the management of post-transplant uretero-vesical anastomotic strictures.

RECENT FINDINGS

To date, only four reported cases of robotic autotransplantation have been described with two being performed completely intra-corporeally. An intra-corporeal approach is feasible for benign conditions, while malignant masses should be inspected and dissected extra-corporeally. Ureteric strictures after renal transplantation are common. To date, the experience with robotic surgical management is limited but has also been shown to be safe and feasible. While robotic autotransplantation is still in its infancy, it is feasible and appears to be safe. Renal allograft function and surgical outcomes are favorable and provide patients the option to have a historically more morbid surgery performed with a minimally invasive approach.

The Impact of the Choosing Wisely Campaign in Urology

OBJECTIVE

To determine if 3 of the Canadian Urological Association's Choosing Wisely recommendations (released in 2013-2014) related to urologic care altered physician and patient behavior.

METHODS

Administrative data from Ontario, Canada between 2008 and 2017 was used. We identified 3 cohorts: First, we determined how many men >66 years of age had a serum testosterone level before starting testosterone therapy. Second, we determined how many boys undergoing an orchiopexy underwent abdominal imaging before their surgery. Third, we determined how many men with low risk prostate cancer underwent a Bone Scan after diagnosis. Piece-wise linear regression was used to evaluate for a significant change after Choosing Wisely.

RESULTS

We identified 13,113 men who had their initial prescription for testosterone filled. Serum testosterone measurement increased over time, from approximately 43% to 68%. There were 9319 boys who underwent an orchiopexy. The use of pre-orchiopexy ultrasound was generally stable (approximately 55%). We identified 27,174 men with low risk prostate cancer. The use of bone scans after diagnosis decreased over time from approximately 24% to 20%. In all 3 of these groups, there was no significant change after Choosing Wisely (P = .74, P = .70, P = .72 respectively).

CONCLUSION

In Ontario, there was no evidence of a significant change in 3 practice patterns that were featured in Choosing Wisely Urology recommendations. Further thought may be needed on how to translate these and future recommendations into behavior change.

Risk of rhabdomyolysis from 5-α reductase inhibitors

PURPOSE

A recent regulatory warning and case reports have described the development of muscle complications with the use of 5-α reductase inhibitors (5ARIs). We wished to determine if there was a link between rhabdomyolysis and 5ARI usage.

METHODS

We used a matched cohort design and linked administrative data from the province of Ontario, Canada, to investigate the risk of rhabdomyolysis in men using either finasteride or dutasteride. A total of 99 covariates were measured. We identified 93 197 men ≥66 years of age who initiated a new prescription for a 5ARI, and they were matched using a propensity score to an equal number of men not prescribed a 5ARI.

RESULTS

New initiation of 5ARIs was not associated with a significantly increased risk of rhabdomyolysis (hazard ratio [HR] 1.21, 95% confidence interval [CI], 1.00-1.48, P = .06). When we examined the risk of rhabdomyolysis in the year prior to the initiation of a 5ARI, we found that men who would go on to use a 5ARI in the future had an elevated risk of rhabdomyolysis even prior to starting the medication (HR 1.31, 95% CI, 1.05-1.64, P = .01). Our secondary outcome of myositis and myopathy was significantly higher among 5ARI users (HR 1.63, 95% CI, 1.48-1.80, P < .01), and this risk was not present prior to 5ARI usage.

CONCLUSION

5-α reductase inhibitors do not appear to be associated with the development of rhabdomyolysis; however, they may be associated with an increased risk of myopathy and myositis.

Association of Suicidality and Depression With 5α-Reductase Inhibitors

IMPORTANCE

There have been concerns raised by patients and regulatory agencies regarding serious psychiatric adverse effects associated with 5α-reductase inhibitors.

OBJECTIVE

To determine if there is an increased risk of suicide, self-harm, or depression among older men starting a 5α-reductase inhibitor for prostatic enlargement.

DESIGN, SETTING, AND PARTICIPANTS

A population-based, retrospective, matched cohort study using linked administrative data for 93 197 men ages 66 years or older (median [IQR] age, 75 [70-80] years) in Ontario, Canada, who initiated a new prescription for a 5α-reductase inhibitor during the study period (2003 through 2013). Participants were matched (using a propensity score that included 44 of our 96 covariates that included medical comorbidities, medication usage, and health care system utilization) to an equal number of men not prescribed a 5α-reductase inhibitor.

EXPOSURES

Duration of finasteride or dutasteride usage.

MAIN OUTCOMES AND MEASURES

Suicide. Secondary outcomes were self-harm and depression.

RESULTS

Men who used 5α-reductase inhibitors were not at a significantly increased risk of suicide (HR, 0.88; 95% CI, 0.53-1.45). Risk of self-harm was significantly increased during the initial 18 months after 5α-reductase inhibitor initiation (HR, 1.88; 95% CI, 1.34-2.64), but not thereafter. Incident depression risk was elevated during the initial 18 months after 5α-reductase inhibitor initiation (HR, 1.94; 95% CI, 1.73-2.16), and continued to be elevated, but to a lesser degree, for the remainder of the follow-up period (HR, 1.22; 95% CI, 1.08-1.37). The absolute increases in the event rates for these 2 outcomes were 17 per 100 000 patient-years and 237 per 100 000 patient-years, respectively. The type of 5α-reductase inhibitor (finasteride or dutasteride) did not significantly modify the observed associations with suicide, self-harm, and depression.

CONCLUSIONS AND RELEVANCE

In a large cohort of men ages 66 years or older, we did not demonstrate an increased risk of suicide associated with 5α-reductase inhibitor use. However, the risk of self-harm and depression were increased compared with unexposed men. This is in keeping with postmarketing experience and patient concerns, and discontinuation of the medication in these circ umstances may be appropriate.

Preoperative Practice Paired With Instructor Feedback May Not Improve Obstetrics-Gynecology Residents' Operative Performance

BACKGROUND

There is evidence that preoperative practice prior to surgery can improve trainee performance, but the optimal approach has not been studied.

OBJECTIVE

We sought to determine if preoperative practice by surgical trainees paired with instructor feedback improved surgical technique, compared to preoperative practice or feedback alone.

METHODS

We conducted a randomized controlled trial of obstetrics-gynecology trainees, stratified on a simulator-assessed surgical skill. Participants were randomized to preoperative practice on a simulator with instructor feedback (PPF), preoperative practice alone (PP), or feedback alone (F). Trainees then completed a laparoscopic salpingectomy, and the operative performance was evaluated using an assessment tool.

RESULTS

A total of 18 residents were randomized and completed the study, 6 in each arm. The mean baseline score on the simulator was comparable in each group (67% for PPF, 68% for PP, and 70% for F). While the median score on the assessment tool for laparoscopic salpingectomy in the PPF group was the highest, there was no statistically significant difference in assessment scores for the PPF group (32.75; range, 15-36) compared to the PP group (14.5; range, 10-34) and the F group (21.25; range, 10.5-32). The interrater correlation between the video reviewers was 0.87 (95% confidence interval 0.70-0.95) using the intraclass correlation coefficient.

CONCLUSIONS

This study suggests that a surgical preoperative practice with instructor feedback may not improve operative technique compared to either preoperative practice or feedback alone.

Ambient Temperature and the Risk of Renal Colic: A Population-Based Study of the Impact of Demographics and Comorbidity

PURPOSE

To examine the impact of ambient temperature on the incidence of emergency department (ED) admissions for acute renal colic and the potential influence demographics and comorbid conditions may have on this.

METHODS

We conducted a population-based time series analysis using linked healthcare databases in Ontario, Canada, which included all residents, aged ≥19 years, who were admitted to an ED from April 2002 to December 2013. The primary outcome was daily number of renal colic emergency department admissions. A distributed lag nonlinear model with 21 days of lag was applied to estimate the cumulative effect of temperature on colic admissions. We estimated risks for cold and heat, defined as temperatures below and above the optimal temperature, which corresponded to the point with minimum risk of colic admissions. We conducted stratified analyses using selected demographics and comorbidities.

RESULTS

During the study period, 423,396 patients presented to an ED with colic. There was a significantly increased risk of colic as ambient temperature increased (rate ratio [RR] = 1.30, 95% confidence interval [CI]: 1.20, 1.42). Subgroup analysis demonstrated an increased risk associated with heat for both genders; however, this risk was more pronounced in males with extreme heat (RR = 1.64 vs 1.22, p = 0.006). In contrast to other age groups, there was an increased risk for those in their 40s (RR = 1.42), 50s (RR = 1.54), and 60s (RR = 1.31) (p = 0.02).

CONCLUSION

Increasing ambient temperature was associated with increased risk of ED visits for colic, particularly in males and those aged 40 to 69 years.

Best Stent Length Predicted by Simple CT Measurement Rather than Patient Height

INTRODUCTION AND OBJECTIVES

Ureteral stent length is important, as stents that are too long might worsen symptoms and too short are at higher risk of migration. The purpose of this study was to determine if patient or radiologic parameters correlate with directly measured ureteral length and if directly measured ureteral length predicts proper stent positioning.

METHODS

During stent placement, ureteral length (ureteropelvic junction to ureterovesical junction distance) was directly measured by endoscopically viewing a ureteral catheter (with 1-cm marking) emanating from the ureteral orifice. A 22, 24, or 26 cm stent was chosen to be closest to the measured ureteral length. For ureters >26 cm, a 26 cm stent was chosen. Ends of an "ideally positioned" stent were fully curled in the renal pelvis and bladder, without crossing the bladder midline. Rates of ideal stent position were compared between patients with matching stent and ureteral lengths and those with stent lengths differing by ≥1 cm (mismatched). The measured ureteral length was correlated with patient height, L1-L5 height, and length measured on CT.

RESULTS

Fifty-nine ureters from 57 patients were included. Height was reasonably correlated with L1-L5 height (Spearman correlation coefficient [rho] = 0.79), although both were poorly correlated with directly measured ureteral length (rho = 0.18 for height and 0.32 for lumbar height). Ureteral lengths measured on CT correlated well with direct measurement (rho = 0.63 for axial cuts and rho = 0.64 for coronal cuts). Matched stent length was associated with higher rates of ideal stent position than mismatched (100% vs 70.9%, p = 0.006).

CONCLUSIONS

CT measurements, rather than height, correlate well with measured length and could be used to choose the appropriate stent length. Stents matching directly measured ureteral lengths are associated with high rates of ideal stent position.

Shockwave Lithotripsy Practice Pattern Variations Among and Between American and Canadian Urologists: In Support of Guidelines

PURPOSE

Shockwave lithotripsy (SWL) is a widely utilized form of treatment for urolithiasis. There are new evidence-based recommendations regarding pre-SWL patient work-up and the performance of SWL. The purpose of this study is to determine practice patterns for SWL and to determine if regional variation exists between Canada and the United States.

MATERIALS AND METHODS

A 19-question survey was prepared. Canadian urologists were surveyed through e-mail correspondence. In the United States, members of the Endourologic Society and members of two large stone management groups were surveyed. Canadian and American results were compared using the chi-square and Fisher's exact tests.

RESULTS

Ninety-four Canadian urologists and 187 U.S. urologists completed the survey. Practice patterns differed between countries. Intravenous sedation was more commonly used in Canada (Canada 94.7% vs United States 17.9%, p < 0.001); routine antibiotics were more commonly given in United States (Canada 2.1% vs United States 78.1%, p < 0.001); a shock rate of 2 Hz was more common in Canada (Canada 76.6% vs United States 16.2%, p < 0.00001); rate of discontinuing ASA for renal and ureteral stone treatment was higher in the United States (renal Canada 88.3% vs United States 95.7%, p < 0.02; ureteral Canada 62.4% vs 90.3%, p < 0.0001); and ureteral stents were more commonly used if treating a large stone or patients with solitary kidneys in the United States (large stones Canada 58.2% vs United States 88.8%, p = 0.0001; solitary kidney Canada 50.6% vs 66.3%, p = 0.02).

CONCLUSIONS

This study highlights the absence of standardization of SWL. Significant regional differences exist in practice patterns and performance of SWL between Canadian and American urologists.