Ricardo Jordão Duarte

Laparoscopic nephrectomy for Wilms’ tumor

The role of minimally invasive surgery for the treatment of pediatric urological tumors has been limited to biopsies and resection for small neuroblastomas and benign tumors. The purpose of this study is to present the experience of a Brazilian group pioneering laparoscopic nephrectomy for Wilms’ tumor. A total of 15 children with unilateral non-metastatic Wilms’ tumor were preoperatively treated with vincristine and actinomycin D, and afterwards were submitted to laparoscopic nephrectomy and lymph node sampling. A Veress needle umbilical punction was performed and a four-trocar transperitoneal approach was used. The tumor was extracted inside a plastic bag and without morcellation through a Pfannenstiel incision. In all 15 patients the tumor was completely removed, as well as lymph node samples and no ruptures occurred. A fibrous capsule involved the tumor, making the dissection easy to perform. Intraoperative bleeding was minimal. The postoperative course was free of complications and all the patients were discharged early. No recurrences or long-term complications have been detected in 7–61 months or more of follow-up. We conclude that laparoscopic nephrectomy for Wilms’ tumor is a feasible and safe procedure in a selected group of children after chemotherapy. It reproduces all the steps of the open surgical approach required to treat this tumor, with the advantages of a short hospital stay and cosmetically more acceptable incisions.

Does Training Laparoscopic Skills in a Virtual Reality Simulator Improve Surgical Performance

BACKGROUND AND PURPOSE Several different methods of teaching laparoscopic skills have been advocated, with virtual reality surgical simulation (VRSS) being the most popular. Its effectiveness in improving surgical performance is not a consensus yet, however. The purpose of this study was to determine whether practicing surgical skills in a virtual reality simulator results in improved surgical performance. MATERIALS AND METHODS Fifteen medical students recruited for the study were divided into three groups. Group I (control) did not receive any VRSS training. For 10 weeks, group II trained basic laparoscopic skills (camera handling, cutting skill, peg transfer skill, and clipping skill) in a VRSS laparoscopic skills simulator. Group III practiced the same skills and, in addition, performed a simulated cholecystectomy. All students then performed a cholecystectomy in a swine model. Their performance was reviewed by two experienced surgeons. The following parameters were evaluated: Gallbladder pedicle dissection time, clipping time, time for cutting the pedicle, gallbladder removal time, total procedure time, and blood loss. RESULTS With practice, there was improvement in most of the evaluated parameters by each of the individuals. There were no statistical differences in any of evaluated parameters between those who did and did not undergo VRSS training, however. CONCLUSION VRSS training is assumed to be an effective tool for learning and practicing laparoscopic skills. In this study, we could not demonstrate that VRSS training resulted in improved surgical performance. It may be useful, however, in familiarizing surgeons with laparoscopic surgery. More effective methods of teaching laparoscopic skills should be evaluated to help in improving surgical performance.

Voiding Dysfunction and the Williams-Beuren Syndrome: A Clinical and Urodynamic Investigation

PURPOSE WBS is an autosomal dominant disorder that includes features such as developmental delay, cardiovascular anomalies, mental retardation and characteristic facial appearance. We systematically investigated the prevalence and spectrum of voiding dysfunction in this population. MATERIALS AND METHODS We prospectively evaluated 16 boys and 12 girls with WBS, with a mean age of 9.7 years (range 3 to 19). Urological evaluation included history of urinary symptoms and impact on quality of life, voiding diary, urodynamics and radiological evaluation with urinary tract sonography, voiding cystourethrography and renal scintigraphy. RESULTS A total of 22 patients (78.6%) were symptomatic, including 15 (53.6%) with a significant negative impact on the quality of life. Increased urinary frequency was the most common complaint, present in 17 patients (60.7%), followed by enuresis (50%) and urge incontinence (42.8%). A total of 14 patients (50%) had urinary tract abnormalities, with bladder diverticula as the predominant anomaly (10 of 23 patients, or 43.5%). Urodynamics revealed detrusor overactivity in 17 patients (60.7%), detrusor-sphincter dyssynergia with detrusor overactivity in 4 (14.3%) and detrusor-sphincter dyssynergia without detrusor overactivity in 2 (7.1%). An average reduction of 28.3% of the cystometric capacity in comparison to expected capacity for age was found (p <0.001). Urodynamic abnormalities were significantly associated with the presence of voiding symptoms (p = 0.003) and bladder diverticula (p = 0.001). CONCLUSIONS Children with the Williams-Beuren syndrome are at high risk for presenting with voiding dysfunction and structural abnormalities, and should undergo a minimum evaluation that includes voiding history and urinary tract sonography, while urodynamics, VCUG and additional studies should be performed in symptomatic patients or those whose initial evaluation shows significant abnormalities.

Extracorporeal shock wave lithotripsy in children: Results and short‐term complications

Aim:  The introduction of extracorporeal shock wave lithotripsy represented an important evolution in urinary tract lithiasis management. The aim of this study is to describe the results of extracorporeal shock wave lithotripsy for the treatment of urinary tract lithiasis in children, focusing on the index of elimination of the calculi and the complications occurring during the procedure and during the following three months.

Pediatric Genitourinary Oncology

Tumors of the kidney, bladder, prostate, testis, and adrenal represent a large part of the adult urologic practice, but are relatively infrequent in children. The natural history and management of these tumors in the pediatric age is different from that of the adults. As result of the successful work of several clinical trial groups in recent decades, there has been a significant improvement in their cure rates. The aim of this article is to review their most significant clinical aspects, as well as to present an update in their management.

Transperitoneal versus extraperitoneal laparoscopic radical prostatectomy during the learning curve: does the surgical approach affect the complication rate?

PURPOSE To compare the perioperative complication rate obtained with the transperitoneal laparoscopic radical prostatectomy (TLRP) and with the extraperitoneal LRP (ELRP) during the learning curve (LC). MATERIALS AND METHODS Data of the initial 40 TLRP (Group 1) were retrospectively compared with the initial 40 ELRP (Group 2). Each Group of patients was operated by two different surgeons. RESULTS The overall surgical time (175 min x 267.6 min; p < 0.001) and estimated blood loss (177.5 mL x 292.4 mL; p < 0.001) were statistically better in the Group 1. Two intraoperative complications were observed in Group 1 (5%) represented by one case of bleeding and one case of rectal injury, whereas four complications (10%) were observed in Group 2, represented by two cases of bleeding, one bladder and one rectal injuries (p = 0.675). Open conversion occurred once in each Group (2.5%). Overall postoperative complications were similar (52.5% x 35%; p = 0.365). Major early postoperative complications occurred in three and in one case in Group 1 and 2, respectively. Group 1 had two peritonitis (fecal and urinary), leading to one death in this group. CONCLUSIONS No statistical differences in overall complication rates were observed. The transperitoneal approach presented more serious complications during the early postoperative time and this fact is attributed to the potential chance of intraperitoneal peritonitis not observed with the extraperitoneal route.

Surgical performance during laparoscopic radical nephrectomy is improved with training in a porcine model.

BACKGROUND AND PURPOSE Becoming proficient in laparoscopic surgery is dependent on the acquisition of specialized skills that can only be obtained from specific training. This training could be achieved in various ways using inanimate models, animal models, or live patient surgery--each with its own pros and cons. Currently, there are substantial data that support the benefits of animal model training in the initial learning of laparoscopy. Nevertheless, whether these benefits extent themselves to moderately experienced surgeons is uncertain. The purpose of this study was to determine if training using a porcine model results in a quantifiable gain in laparoscopic skills for moderately experienced laparoscopic surgeons. MATERIALS AND METHODS Six urologists with some laparoscopic experience were asked to perform a radical nephrectomy weekly for 10 weeks in a porcine model. The procedures were recorded, and surgical performance was assessed by two experienced laparoscopic surgeons using a previously published surgical performance assessment tool. The obtained data were then submitted to statistical analysis. RESULTS With training, blood loss was reduced approximately 45% when comparing the averages of the first and last surgical procedures (P=0.006). Depth perception showed an improvement close to 35% (P=0.041), and dexterity showed an improvement close to 25% (P=0.011). Total operative time showed trends of improvement, although it was not significant (P=0.158). Autonomy, efficiency, and tissue handling were the only aspects that did not show any noteworthy change (P=0.202, P=0.677, and P=0.456, respectively). CONCLUSIONS These findings suggest that there are quantifiable gains in laparoscopic skills obtained from training in an animal model. Our results suggest that these benefits also extend to more advanced stages of the learning curve, but it is unclear how far along the learning curve training with animal models provides a clear benefit for the performance of laparoscopic procedures. Future studies are necessary to confirm these findings and better understand the impact of this learning tool on surgical practice.

Wilms Tumor: A Retrospective Study of 32 Patients Using Videolaparoscopic and Open Approaches

OBJECTIVE To compare videolaparoscopic nephrectomy and the open technique as treatments for Wilms tumor, specifically the surgical results, immediate and long-term complications, and patient survival. METHODS A review of charts of children with unilateral Wilms tumor was performed. There were 2 surgical groups: (1) only open surgery and (2) videolaparoscopy. Complications, transfusion, ruptures, margins, conversions, lymph nodes, and relapse were analyzed. RESULTS Seventeen children underwent laparoscopic nephrectomy and 15 underwent open nephrectomy. Mean surgical time was 164.71±26.07 minutes for the laparoscopic group, and there were no conversions or ruptures. The mean specimen weight was 145.01±105.85 g for the laparoscopic group and 257.40±162.70 g for the open surgery group. There was 1 preoperative rupture in the open surgery group. Transfusions were not required in either group. The surgical margins were positive in 1 of 17 cases (5.9%) in the laparoscopic group and in 3 of 15 cases (20%) in the open surgery group. One of the 17 (5.9%) laparoscopy-treated patients and 2 of the 15 open surgery-treated patients (13.3%) presented with local tumor relapse. The 5-year event-free survival rate was 93.3% (95% confidence interval, 0.61-0.99) for the laparoscopic group and 79.6% (95% confidence interval, 0.37-0.95] for the open surgery group (P=.446). CONCLUSION Both techniques showed similar immediate and long-term results.

Does Warm-Up Training in a Virtual Reality Simulator Improve Surgical Performance? A Prospective Randomized Analysis.

INTRODUCTION Virtual reality surgical simulators (VRSS) have been showing themselves as a valuable tool in laparoscopy training and education. Taking in consideration the effectiveness of the VRSS, new uses for this tool have been purposed. In sports, warming up before exercise clearly shows benefit in performance. It is hypothesized that warming up in the VRSS before going to the operating room may show benefit in surgical performance. OBJECTIVE Verify whether there is benefit in surgical performance with preoperatory warm-up using a VRSS. MATERIALS AND METHODS A total of 20 medical students with basic knowledge in laparoscopy were divided in 2 groups (I and II). Group I performed a laparoscopic cholecystectomy in a porcine model. Group II performed preoperative warm-up in a VRSS and then performed a laparoscopic cholecystectomy in a porcine model. The performance between both groups was compared regarding quantitative parameters (time for dissection of the gallbladder pedicle, time for clipping the pedicle, time for cutting the pedicle, time for gallbladder removal, total operative time, and aspirated blood loss) and qualitative parameters (depth perception, bimanual dexterity, efficiency, tissue handling, and autonomy) based on a previously validated score system, in which the higher the score, the better the result. Data were analyzed with level of significance of 5%. RESULTS The group that underwent preoperative warm-up (group II) showed significantly superior results as to the time for dissection of the gallbladder pedicle (11.91 ± 9.85 vs. 4.52 ± 2.89min, p = 0.012), time for clipping the pedicle (5.51 ± 2.36 vs. 2.89 ± 2.76min, p = 0.004), time for cutting the pedicle (1.84 ± 0.7 vs. 1.13 ± 0.51, p = 0.019), aspirated blood loss (171 ± 112 vs. 57 ± 27.8ml, p = 0.006), depth perception (4.5 ± 0.7 vs. 3.3 ± 0.67, p = 0.004), bianual dexterity (4.2 ± 0.78 vs. 3.3 ± 0.67, p = 0.004), tissue handling (4.2 ± 0.91 vs. 3.6 ± 0.66, p = 0.012), and autonomy (4.9 ± 0.31 vs. 3.6 ± 0.96, p = 0.028). There was no difference in time for gallbladder removal (11.58 ± 4.31 vs. 15.08 ± 4.51min, p = 0.096), total operative time (30.8 ± 11.07 vs. 25.60 ± 5.10min, p = 0.188), and efficiency (4 ± 0.66 vs. 3.6 ± 0.69, p = 0.320). CONCLUSION The practice of preoperative warm-up training seems to benefit surgical performance even in subject with mild laparoscopic experience.

Avaliação de dois sensores portáteis para mensuração da glicemia em cães

The clinical and analytical accuracy of two portable meters for glucose measurement in dogs was evaluated. Blood glucose values obtained by the use of portable meters were compared to those obtained using the glucose oxidase reference method, by means of correlation and error analysis. Results obtained with the blood glucose meters were not different from those obtained with the reference method. Both apparatus evaluated are adequate for use in dogs.