Carlos E. Méndez-Probst

2010 Update: Guidelines for the management of benign prostatic hyperplasia

Within the past decade, a number of significant advancements have occurred in our knowledge of benign prostatic hyperplasia (BPH) resulting in new approaches to both the diagnosis and treatment of this common and potentially progressive condition of aging men. The current document attempts to summarize the state-of-the-art knowledge regarding BPH and to highlight the essential diagnostic and therapeutic information in a Canadian context. The information included in this document was obtained from a MEDLINE search of the English language literature. Although references of historical importance are included, management recommendations are based on literature published between 2000 and 2009. These guidelines are directed toward the typical male patient over 50 years of age, presenting with lower urinary tract symptoms (LUTS) believed to be associated with benign prostatic obstruction (BPO). Men with LUTS associated with non-BPO causes will require more extensive diagnostic workup, different treatment considerations and their management will not be covered in this document. In this document we will address both diagnostic and treatment issues. Diagnostic guidelines are described in the following terms as: mandatory, recommended, optional or not recommended. Guidelines for treatment are described using the terminology: standard of care (evidence-based, whenever possible), optional (insufficient evidence or patient preference) or not recommended (based on the best available evidence). Whenever possible, levels of evidence and grades of recommendation will be provided to support guideline statements.

The use of triclosan eluting stents effectively reduces ureteral stent symptoms: a prospective randomized trial.

Study Type – Therapy (RCT)

Risk Factors for Perinephric Hematoma Formation After Shockwave Lithotripsy: A Matched Case-Control Analysis

PURPOSE To determine the incidence of and evaluate the potential risk of a symptomatic perinephric hematoma (PNH) after shockwave lithotripsy (SWL) with the Storz Modulith SLX-F2 device. PATIENTS AND METHODS Patient and treatment-related data from 6172 SWL treatments for proximal ureteral and kidney stones were collected prospectively from April 2006 to August 2010. Patients in whom signs or symptoms of a PNH developed after SWL were investigated with imaging studies. Each patient identified with a PNH was matched with four controls using sex, age (±5 years), shockwave rate, energy and number, and no SWL within the previous 6 months as the matching variables. The baseline characteristics of the 21 cases and 84 controls were compared using the Student t test. The independent variables of hypertension (intraoperative value >140/90 mm Hg), anticoagulant/antiplatelet drugs, obesity (body mass index ≥30), and diabetes were compared using a conditional logistic regression analysis. The dependent variable was hematoma. RESULTS A PNH developed after SWL with the Storz Modulith SLX-F2 device in 21 (0.34%) adult patients (19 men, 2 women) with a mean age of 55.2 years. Significant risk factors identified included intraoperative hypertension (hazard ratio [HR] 3.302, 1.066-10.230, P=0.0384) and anticoagulant/antiplatelet medications (HR 4.198, 1.103-15.984, P=0.0355). Diabetes (P=0.1043) and obesity (P=0.1021) were not associated with PNH. CONCLUSIONS A clinical PNH occurred in less than 1% of our population. This is consistent with reports from earlier generation devices. Risk factors identified for hematoma formation were intraoperative hypertension and the use of anticoagulant/antiplatelet drugs.

Current Status of Ureteral Stent Technologies: Comfort and Antimicrobial Resistance

The placement of a ureteral stent is one of the most commonly performed urologic procedures. Indwelling ureteral stents are often accompanied by significant patient morbidity, including lower urinary tract symptoms, flank pain, and urinary tract infections. This article reviews the current state of ureteral stent technology developed to address the problem of stent discomfort and infection.

Emphysematous Pyelonephritis: Multicenter Clinical and Therapeutic Experience in Mexico

OBJECTIVE To analyze the outcomes of emphysematous pyelonephritis (EPN), the impact of different treatment modalities, and to determine risk factors associated with mortality. METHODS We retrospectively reviewed cases of EPN from 3 tertiary care institutions in Mexico. The diagnosis was confirmed with computed tomographic scan. Treatment was classified as follows: medical management (MM), minimally invasive, and surgical. Demographic, clinical, biochemical, and radiological characteristics were assessed and compared between survivors and nonsurvivors. Comparison was assessed using 1-way analysis of variance and chi-square. Univariate and multivariate logistic regression analyses were performed to determine prognostic factors. Main end point was mortality. RESULTS A total of 62 patients were included (49 women and 13 men), with a mean age of 53.9 years. The most common comorbidities were diabetes (69.3%) and hypertension (40.3%). Escherichia coli was the most common isolated microorganism (62.7%). MM was provided to 24.2%, minimally invasive treatment to 51.6%, open drainage to 19.3%, and emergency nephrectomy to 4.8%. Overall mortality was 14.5% and was similar among different treatment modalities (P=.06). Survivors were younger (P=.004), had lower creatinine (P=.002), and better estimated glomerular filtration rate (P=.007). In univariate analysis, age (P=.009), creatinine (P=.009), and need for nephrectomy (P=.03) were associated with mortality. In multivariate logistic regression analysis, creatinine (odds ratio 1.56, 95% confidence interval 1.03-2.35, P=.03) and nephrectomy (odds ratio 9.7, 95% confidence interval 1.007-93.51, P=.049) remained significant predictors of mortality. CONCLUSION EPN needs an aggressive MM and stepwise approach; nephrectomy should be the last resort of treatment. Creatinine level and need for nephrectomy are the strongest predictors of mortality according our analysis.

Percutaneous Nephrolithotomy of Caliceal Diverticular Calculi: A Single Center Experience

BACKGROUND AND PURPOSE Caliceal diverticula are rare renal anomalies present in approximately 0.6% of the population. They are associated with calculi in 50% of cases. Therapeutic options include several minimally invasive techniques. We report a retrospective review of outcomes and complications from our series of patients who were treated with a percutaneous approach. PATIENTS AND METHODS A database of outcomes related to percutaneous nephrolithotomy (PCNL) has been maintained at our institution since 1992. Data on all patients with caliceal diverticular stones who underwent PCNL during a 17-year period from 1992 to 2009 were reviewed retrospectively. Our preferred approach to PCNL in these patients is to puncture directly into the diverticulum and to try to advance a guidewire through the infundibular neck. In cases where the caliceal neck could not be intubated, we performed a transdiverticular approach with creation of a neoinfundibulum as a salvage procedure. We evaluated the two techniques with regard to stone-free rates and early postoperative complications. RESULTS Seventy-six procedures were performed. The mean age was 43 years (range 17-72 y). The mean stone area was 583 mm(2). The surgical approach was direct puncture in 47, transdiverticular in 20, retrograde in 8, and unknown in 1 patient. Eight patients underwent lining fulguration. The average duration of surgery was 75 minutes (23-169 min) with an average hospital stay of 4.7 days. There were a total of 23 complications, of which 11 necessitated additional intervention. The overall stone-free rates were 77% and 89% for direct puncture and transdiverticular approaches, respectively. CONCLUSIONS The percutaneous management of caliceal diverticular calculi is highly effective and can be accomplished with low morbidity.

A multicentre single-blind randomized controlled trial comparing bipolar and monopolar transurethral resection of the prostate

INTRODUCTION Monopolar transurethral resection of the prostate (TURP) is the gold standard surgical therapy for men with lower urinary tract symptoms due to benign prostatic hyperplasia. Although generally considered safer, TURP experience is limited in Canada. METHODS Forty-three patients from 5 Canadian centres were randomized to TURP with either bipolar or monopolar platforms. Patients underwent baseline determinations of American Urological Association (AUA) symptom score, peak urinary flow rate, post-void residual bladder volume and transrectal ultrasound prostate volume. Primary outcome measures were improvement in AUA symptom score, quality of life assessment and bother assessment. Secondary outcomes included procedural times, duration of catheterization, length of hospitalization, complications and the degree of thermal artifact in tissue specimens. Patients were followed for 6 months. RESULTS Twenty-two patients were treated with bipolar and 21 with monopolar TURP. Preoperative demographics were not statistically different between groups. Postoperative data collection times were equivalent in AUA symptom, quality of life, bother and sexual function assessments. No differences were observed in the procedure time (60.7 min, bipolar vs. 47.4, monopolar) or the duration of urethral catheterization (1.5 days, bipolar vs. 1.1, monopolar). More patients in the bipolar group were discharged on the same day of surgery. There were no differences in the degree of tissue thermal artifact or complication rate. CONCLUSION This trial suggests equivalent short-term outcomes for men undergoing monopolar or bipolar TURP.

Stray electrical currents in laparoscopic instruments used in da Vinci® robot-assisted surgery: an in vitro study.

BACKGROUND AND PURPOSE The da Vinci(®) surgical system requires the use of electrosurgical instruments. The re-use of such instruments creates the potential for stray electrical currents from capacitive coupling and/or insulation failure. We used objective measures to report the prevalence and magnitude of such stray currents. MATERIALS AND METHODS Thirty-seven robotic instruments were tested using an electrosurgical unit (ESU) at pure coagulation and cut waveforms at four different settings. Conductive gel-coated instruments were tested at 40W, 80W, and maximum ESU output (coagulation 120W, cut 300W). The magnitude of stray currents was measured by an electrosurgical analyzer. RESULTS At coagulation waveform in open air, 86% of instruments leaked a mean of 0.4W. In the presence of gel-coated instruments, stray currents were detected in all instruments with means (and standard deviation) of 3.4W (± 2), 4.1W (± 2.3), and 4.1W (± 2.3) at 40W, 80W, and 120W, respectively. At cut waveform in open air, none of the instruments leaked current, while gel-coated instruments leaked a mean of 2.2W (± 1.3), 2.2W (± 1.9) and 3.2W (± 1.9) at 40W, 80W, and 300W, respectively. CONCLUSIONS All tested instruments in our study demonstrated energy leakage. Stray currents were higher during coagulation (high voltage) waveforms, and the magnitude was not always proportionate to the ESU settings. Stray currents have the potential to cause electrical burns. We support the programmed end of life of da Vinci instruments on the basis of safety. Consideration should be given to alternate energy sources or the adoption of active electrode monitoring technology to all monopolar instruments.

Fusion of the seminal vesicles discovered at the time of robot-assisted laparoscopic radical prostatectomy

The reported incidence of seminal vesicle anomalies is low, and it usually occurs in association with other genitourinary anomalies, thus frequently diagnosed by a cluster of fertility, pain or obstructive symptoms. We present a case of a clinically silent seminal vesicle fusion encountered during a robotic assisted radical prostatectomy. Awareness of potential congenital anomalies is crucial for surgeons, to prevent surgical complications or adverse outcomes as a result of the altered anatomy.