Stratification of Expert vs Novice Laparoscopists Using the Basic Laparoscopic Urologic Surgery (BLUS) Curriculum at a Single Institution.

PURPOSE: To assess determinants of performance applying the tasks of the Basic Laparoscopic Urologic Surgery (BLUS) skills curriculum administered at a single institution. METHODS: After obtaining institutional review board approval, fourth-year medical students, urology residents (postgraduate year 1-5), and staff attending surgeons from an academic institution were recruited. Participants were grouped by level of experience and evaluated on 4 different BLUS modules testing fundamental laparoscopic techniques from September 2012 to September 2013. Task completion time (TCT) and missed objectives were compared with previous laparoscopic experience, amount of endourological training, and scores obtained through the EDGE simulator. RESULTS: TCTs among the participants were slower and accrued greater errors in the novice group (n = 10) than in the intermediate-level (n = 9) and expert-level (n = 9) groups. Completion times on the peg transfer were 213.4, 128.1, and 108.7 seconds (p < 0.05); on the circle cutting were 182.4, 128.3, and 97.2 seconds (p < 0.05); on the clip application were 44.4, 43.2, and 38.1 seconds (p = 0.08); and on the suturing were 286.1, 177.3, and 123.6 seconds (p < 0.05) for novice, intermediate, and expert groups, respectively. When past laparoscopic numbers of participants were compared with TCTs, a positive correlation of R(2) = 0.39 was seen, signifying a relationship between number of laparoscopic cases and TCT outcomes. CONCLUSION: Performance on the EDGE simulator device during the BLUS modules significantly correlated with the amount of laparoscopic experience. Increase in the years of experience and number of laparoscopic cases led to faster and more accurate TCTs.

Urinary cystatin C and NGAL as early biomarkers for assessment of renal ischemia-reperfusion injury: a serum marker to replace creatinine?

PURPOSE: To assess application of cystatin C and neutrophil gelatinase-associated lipocalin (NGAL) as biomarkers for renal ischemic injury. We also evaluated the use of allopurinol as a renoprotective agent. A second goal was to assess cystatin C as a biomarker in patients undergoing partial nephrectomy. METHODS: Using 58 Sprague-Dawley rats, we evaluated urinary cystatin C (n=26) and NGAL (n=32) as a biomarker for renal ischemia injury. Half of the rats were pretreated with allopurinol; the other cohort served as a control. The right renal hilum was ligated in all rats, thereby creating a solitary kidney model. After a 30-minute stabilization period, the left hilum was clamped for time periods of 15, 30, and 60 minutes. Urinary levels of cystatin C and NGAL were then measured at the following time points: Preclamp (after the 30-minute stabilization period) and postclamp (30, 45, and 60 minute periods after unclamping). For our clinical subjects, serum cystatin C levels (n=17) were obtained preoperatively, at the induction of anesthesia before robot-assisted partial nephrectomy, immediately postoperatively, and on postoperative days 1 and 2. Three of these patients had their tumors excised off clamp and served as controls. We then estimated glomerular filtration rate by using the Creatinine-Cystatin C Equation. RESULTS: Urinary levels of cystatin C and NGAL increased after renal clamping. The 30-minute period of ischemia demonstrated the greatest increase of these biomarkers. Allopurinol did appear to serve a renoprotective function in those animals undergoing 30-minute clamp times. In our clinical patients, the serum cystatin C levels did increase at each postoperative time point, but remained nonelevated in the control group. CONCLUSIONS: Cystatin C and NGAL both appear to be useful biomarkers of renal injury. Studies with larger numbers are needed, however. Also, allopurinol does exhibit renoprotective effects against ischemic injury.

Bilateral synchronous sporadic renal masses: intermediate functional and oncological outcomes at a single institution.

PURPOSE: To review the intermediate term oncologic and functional outcomes after the surgical management of bilateral renal masses (BRM). MATERIALS AND METHODS: After obtaining Institutional Review Board approval, the Tulane renal surgery database (n = 890 patients) was queried for patients presenting with synchronous bilateral enhancing renal masses (n = 30 renal units). We performed a retrospective chart review evaluating oncologic and functional outcomes, specifically with respect to local recurrence and metastatic disease. We also reviewed changes in glomerular filtration rates. RESULTS: Of the 30 renal units were operated on for BRM concerning for renal cell carcinoma, 25 kidneys harbored malignancy (83.3 %). The average tumor size was 3.35 cm. Treatment of each kidney was staged; average time period to treatment of contralateral side was 3.5 months. Estimated GFR (eGFR) for these same pre-operative patients was 59 ml/min/1.73 m(2) (range 25-89). The average creatinine after treatment of one kidney was available for all patients and was 1.5 (range 0.7-2.8), with an average eGFR of 51.8 (range 29-87). The average creatinine after the second operation for these same 15 patients was 1.79 (range 0.9-3.7) with an average GFR of 41.9 (range 17-78). No patient had to undergo temporary dialysis. An average change in GFR after the second, contralateral procedure on the kidney was 17.07 mg/dl. Average oncologic follow-up was 608 days. Excluding two patients who presented with metastatic disease, the average recurrence-free survival was 92.8 %. CONCLUSION: Our data continue to underscore the need for nephron sparing surgery (NSS), especially in the setting of BRM. The average decline in GFR of 28.9 % after treatment of both kidneys and renal cell carcinoma recurrence-free rate of 92.3 % further support the efficacy of NSS in these patients.

Leukocyte inflammatory response in a rat urinary bladder regeneration model using porcine small intestinal submucosa scaffold.

Small intestinal submucosa (SIS) is a biodegradable scaffold that supports bladder regeneration after partial cystectomy. We sought to define the inflammatory response present in a rat bladder augmentation model using distal ileal SIS. Fifteen Sprague-Dawley rats underwent hemi-cystectomy followed by anastomosis of a bladder patch of SIS. Bladders were excised after days 2, 7, 14, 28, and 56. Tissue regeneration was evaluated by standard hematoxylin and eosin. Immunohistochemical staining was used to quantify neutrophils, macrophages, eosinophils, and mast cells. Total cell counts per unit area were compared between native and graft portions of the bladder for each cell type across the entire time course. Statistical analyses were conducted with the Wilcoxon Rank-Sum and Kruskal-Wallis tests. All tests were two-sided with significance set at p < 0.05. These inflammatory responses evolved consistently across all bladders over time. Neutrophil and eosinophil numbers were highest at day 2 and decreased over the 56-day period. In contrast, macrophage and mast cell numbers were low at days 2, 7, and 14; peaked at day 28; and decreased once again at day 56. Cell counts at native and graft sites were equivalent for all cell types, except neutrophils, which were more commonly found in the graft (124 vs. 24 cells/mm(2), p = 0.009). Thus, the inflammatory processes change over time during SIS-mediated bladder regeneration. Similar cell densities are present between the native and SIS portions of the bladder, but neutrophils predominate in the graft areas.

Temporal differentiation and maturation of regenerated rat urothelium.

OBJECTIVE: To determine if porcine small intestinal submucosa (SIS)-regenerated urothelium expresses markers of urothelial differentiation, uroplakin and zona occludens-1 (ZO-1), and whether their expression correlates with the histological appearance of the urothelium. MATERIALS AND METHODS: In all, 15 rats underwent partial cystectomy and bladder replacement with SIS. Regenerated bladders were harvested at either 2, 7, 14, 28, or 56 days after SIS grafting. Histological examination with haematoxylin and eosin staining was conducted to assess tissue regeneration. Immunohistochemistry was performed with uroplakin and ZO-1 antibodies. RESULTS: By 14 days after SIS grafting, the urothelial layer was completely confluent over the SIS. Expression of uroplakin and ZO-1, evident at 2 days after SIS grafting, progressed from a cytoplasmic pattern of expression to a mature pattern of cytoplasmic and membrane expression by 56 days after SIS grafting. CONCLUSION: In vivo tissue regeneration produces histologically and phenotypically mature urothelium within 2 weeks of SIS implantation. Regeneration of functional urothelium is probably essential for the subsequent development of the remaining bladder.