Samuel Abourbih

Kidney, Ureter, and Bladder (KUB): A Novel Grading System for Encrusted Ureteral Stents

OBJECTIVE To introduce a grading system (kidney, ureter, and bladder [KUB]) to identify encrusted stents that may require multiple surgeries, multimodal surgery, and operative time > 180 minutes for successful removal. METHODS One hundred ten retained encrusted ureteral stents were retrospectively scored using the KUB grading system and this score was correlated with operative time, need for multiple surgeries or multimodal surgery, and stone-free rate. Data analysis was performed with t test, Mann-Whitney U test, and chi-square tests. A P value of <0.05 was considered statistically significant. RESULTS Average indwelling stent time was 17.2 months (0.7-139.0). There were 83.6% of stents removed in a single surgery, with 63.0% of these requiring multimodal surgery. K score ≥ 3 was associated with multiple surgeries (odds ratio [OR] 3.59, P = .006), multimodal surgery (OR 2.44, P = .04), operative time > 180 minutes (OR 3.80, P = .001), and lower stone-free rate (OR 0.23, P = .02). U score ≥ 3 was associated with operative time > 180 minutes (OR 3.28, P = .003). B score ≥ 3 was associated with lower stone-free rate (OR 0.23, P = .020). Total score ≥ 9 was associated with multiple surgeries (OR 4.19, P = .001), operative time > 180 minutes (OR 3.45, P = .002), and lower stone-free rate (OR 0.13, P = .001). CONCLUSION The KUB system identifies stents at risk for requiring multiple surgeries, multimodal surgery, and operative time > 180 minutes. It also correlates with stone-free rate. This grading system can help surgeons manage patient expectations and predict surgical complexity.

Elevated Renal Pelvic Pressures during Percutaneous Nephrolithotomy Risk Higher Postoperative Pain and Longer Hospital Stay

Purpose Renal pelvic pressure may vary during percutaneous nephrolithotomy. We sought to determine the relationship of postoperative pain to endoscope caliber, renal pelvic pressure and hospital stay. Materials and Methods We reviewed the records of 20 percutaneous nephrolithotomies done under ureteroscopic guidance with renal pelvic pressure monitoring. The ureteroscope working channel was connected to a pressure transducer and used to determine renal pelvic pressure at baseline, when irrigating with a 26Fr rigid nephroscope and a 16Fr flexible nephroscope, and during suction. Patient demographics, operative characteristics, Likert pain scores and length of hospital stay were compared as stratified by average renal pelvic pressure. The Mann‐Whitney U and Fisher exact tests were used with p <0.05 considered significant. Results A total of 220 measurements were recorded in 20 patients undergoing single access percutaneous nephrolithotomy. Mean patient age was 55.2 years (range 20 to 77) and mean body mass index was 32.4 kg/m2 (range 18 to 53.3). Rigid nephroscopy resulted in significantly higher average renal pelvic pressure than flexible nephroscopy (30.3 vs 12.9 mm Hg, p = 0.007). Average renal pelvic pressure was 30 mm Hg or greater in 7 patients (35%) undergoing rigid nephroscopy and in none (0%) undergoing flexible nephroscopy (p <0.01). Patients exposed to an average renal pelvic pressure of 30 mm Hg or greater during rigid nephroscopy had significantly higher average pain scores (p = 0.004) and longer hospital stays (p = 0.04) than patients with renal pelvic pressure less than 30 mm Hg. Average renal pelvic pressure 30 mm Hg or greater during rigid nephroscopy was also associated with a longer skin to calyx distance (105.5 vs 79.7 mm, p = 0.03). Conclusions Knowledge of the factors that influence renal pelvic pressure and methods to control pressure extremes may improve patient outcomes during percutaneous nephrolithotomy.

Efficacy of antegrade and retrograde warm saline pyeloperfusion during renal cryoablation for ureteral preservation

Objective Cryoablation of renal tumors adjacent to the ureter or pelvicalyceal system carries risks for thermal injury of the collecting system. Although cold antegrade perfusion has been described for radiofrequency ablation, warm saline perfusion for renal cryoablation has not been well-characterized. The purpose of this study was to determine the safety and feasibility of antegrade and retrograde warm saline perfusions during percutaneous renal cryoablation. Material and methods A retrospective review was performed on 136 patients treated with percutaneous renal cryoablation at a single academic institution between 2009 and 2015. Six patients undergoing antegrade (n=3) or retrograde (n=3) warm saline perfusion for protection of the collecting system were identified. Warm saline was perfused through a 4 French nephrostomy tube in the antegrade technique and through a 6 French end-hole catheter in the retrograde technique. Outcome measures were tumor recurrence rates, success of urothelial preservation, hospital stay, blood loss and procedural time. Results Four tumors were in the lower pole and two tumors in the middle pole. The mean distance from tumor to ureter was 6.8 mm (0.8-11.5 mm) and no patient developed ureteral stricture. There was no tumor recurrence at a median follow-up of 37.3 months (7-65). The median procedural time was 3 hours and 13 minutes. One patient in each group developed minor complications (Clavien I and II) and there were no major complications. Conclusion This study demonstrates the feasibility of antegrade and retrograde warm saline perfusion for ureteral preservation during cryoablation, without compromising oncologic outcomes.

Impact of a Wireless System upon Verbal Communication in a Simulated Robotic Operating Theater

OBJECTIVE To compare the efficacy of communication via the standard Da Vinci Si speaker system with a wireless, hands-free audio system in a prospective blinded study. METHODS Nine hundred and sixty surgical phrases were spoken in a simulated robotic operating room (OR), including 480 phrases expressed via the Da Vinci Si speakers and 480 phrases expressed through a wireless, hands-free system. Using a dual console robotic system, communication was evaluated. Wireless headsets were given to the console and assistant robotic console surgeons, bedside assistant, anesthesiologist, and circulating nurse. An accurate response was defined as hearing the phrase correctly and transcribing it on a data sheet. The primary outcome was the number of correct phrases recorded during the study and secondary outcomes included subjective clarity and effectiveness of communication reported using a Likert scale. RESULTS Overall, the wireless, hands-free system increased the accuracy of communication (390/480 [81.3%]) compared to the conventional robotic system (310/480 [64.4%]; P <.001). The bedside assistant, anesthesiologist, and circulating nurse had significantly fewer correct phrases recorded than the assistant robotic console surgeon when using the robotic speakers (P <.05 for all). In contrast, there were no significant differences in the number of correct phrases recorded between different positions when using the wireless system. Subjectively, the wireless system resulted in improved clarity and effectiveness of communication (P = .021; P <.001, respectively). CONCLUSION Robotic operating systems have intrinsic barriers to effective communication between the surgeon and the rest of the operating room team. Improved communication could reduce surgical errors and improve patient safety.

Conventional Versus Computer-assisted Stereoscopic Ultrasound Needle Guidance for Renal Access: A Randomized Crossover Bench-top Trial

PURPOSE Ultrasound (US) guidance during renal access and mass biopsy reduces radiation exposure, but can be technically challenging. A needle guidance system might simplify these procedures. The purpose of this randomized crossover trial was to compare conventional and computer-assisted US needle guidance systems for renal access and mass biopsy. MATERIALS AND METHODS Seventy-one subjects were randomized to perform renal access or mass biopsy on a phantom using conventional and computer-assisted US guidance in a crossover study design. The primary outcome was success rate including subgroup analysis by experience level. Secondary outcomes included total procedure time, time to hit target, number of course corrections, and total punctures. In addition, subjective preferences of participants were also collected. RESULTS Procedure success rate was higher with the computer-assisted US than with conventional US for both novice (98.0% (48/49) vs 81.6% (40/49); p < 0.001) and experienced US users (100% (22/22) vs 81.8% (18/22); p < 0.001). Computer-assisted US significantly shortened the total procedure time (94.0 seconds vs 192.9 seconds; p ≤ 0.001), time required to hit the target (62.5 seconds vs 121.6 seconds; p ≤ 0.001), and the number of course corrections (0.56 vs 2.89; p < 0.001) compared with conventional US. Computer-assisted US did not significantly reduce the number of needle punctures (1.75 vs 2.39; p = 0.132). Seventy-three percent of subjects preferred the computer-assisted US system. CONCLUSION A computer-assisted needle guidance system increases effective US targeting for renal access and mass biopsy for novice and experienced users.

Do Illuminated Foot Pedals Improve the Speed and Accuracy of Pedal Activation During Endoscopic Procedures

PURPOSE Endourologic procedures such as percutaneous nephrolithotomy (PCNL) employ the use of foot pedals in low-light operating room (OR) settings. These pedals can be especially difficult to locate or distinguish when several pedals are present during a single operation. Improper instrument activation in the OR has led to serious complications ranging from unintentional electrocautery to patient burns and even an intraoperative explosion. This study evaluates the impact of color-coded illumination on speed and efficiency of foot pedal activation. MATERIALS AND METHODS During a simulated PCNL procedure, the foot pedals for a C-arm, laser, and ultrasonic lithotripter (USL) were placed in random positions. Ten participants performed pedal activation in a randomized sequence. Objective outcomes included time to instrument activation, number of attempted pedal presses, number of incomplete pedal presses, and number of incorrect pedal presses. Subjective preferences for pedal illumination were also determined. Data were analyzed using Mann-Whitney U, Wilcoxon signed-rank, and Chi-square tests with p < 0.05 indicating statistical significance. RESULTS Illuminated foot pedals were associated with decreases in the average activation time for all instruments collectively (3.95 seconds vs 6.49 seconds; p = 0.017) and individually (C-arm: 3.07 seconds vs 4.21 seconds; p = 0.006; laser: 13.04 seconds vs 15.18 seconds; p < 0.001; USL: 3.28 seconds vs 4.91 seconds; p < 0.001) compared with nonilluminated pedals. Illuminated pedals were associated with fewer attempted pedal presses (33.5 vs 39.5; p = 0.007) and incomplete pedal presses (1.5 vs 8.5; p = 0.002). The number of incorrect pedal presses decreased with illumination, but this did not reach statistical significance (0 vs 0.5; p = 0.08). Participants reported that illumination simplified pedal activation and recommended its use (p < 0.01). CONCLUSION Color-coded illumination improved the speed and efficiency of foot pedal activation during simulated PCNL. Participants subjectively preferred using illuminated foot pedals for endourologic procedures and felt that they improved safety and efficiency.

MP59-17 SUBCLINICAL RHABDOMYOLYSIS: AN UNDER-RECOGNIZED CONTRIBUTOR TO POSTOPERATIVE ACUTE KIDNEY INJURY IN PATIENTS UNDERGOING MINIMALLY INVASIVE UROLOGIC SURGERY

model (Spearman rho of 0.779) demonstrating preoperative GFR and GFR loss at 6 weeks post-op as the most important predictive factors. 10-year overall risk of NRCM was 29%. Significant predictors of NRCM were preoperative GFR, new baseline GFR, age, diabetes, and hypertension (all p<0.05). A predictive nomogram for 10-year NRCM was created with a c-index 0.71, demonstrating age and preoperative GFR as the most important predictive factors. GFR loss with surgery, as would be seen with typical PN vs. RN, only changed absolute mortality risk by 1-3% in nomogram-based examples (see Figure). CONCLUSIONS: GFR loss with RCS, which is directly related to choice of PN vs RN, strongly influences risk of developing CKD, but has much less impact on long-term survival. In contrast, age and preoperative GFR are much more robust predictors of 10year NRCM.

PD21-04 COMPARISON OF ULTRASOUND-GUIDED, CONVENTIONAL FLUOROSCOPIC, AND A NOVEL LASER DIRECT ALIGNMENT RADIATION REDUCTION TECHNIQUE FOR PERCUTANEOUS NEPHROLITHOTOMY

There was no association between patient0s CCI, age, race, insurance, hospital location (urban vs non-urban, and hospital type (teaching vs non-teaching) with regard to physician specialty obtaining RA. On multivariable analysis, RA by urologist was associated with lower rates of any complication (Clavien 1-5), shorter hospitalization (<2 days) and lower direct admission costs (<

V7-06 PERCUTANEOUS EXTERNALLY ASSEMBLED LAPAROSCOPIC (PEAL) SURGERY FOR FOWLER-STEPHENS ORCHIOPEXY: A VIDEO PRESENTATION

12,515) Figure 1. CONCLUSIONS: PCNL is performed with urologists obtaining percutaneous access the minority of the time in the United States. Highvolume urologists are more likely to obtain their own access. Access by urologist is associated with lower overall complications, shorter hospitalizations, and lower direct hospital costs.

PD11-04 CONVENTIONAL VERSUS COMPUTER ASSISTED STEREOSCOPIC ULTRASOUND NEEDLE GUIDANCE FOR RENAL ACCESS: A RANDOMIZED BENCH-TOP CROSSOVER TRIAL

METHODS: A collaborative team was formed and consisted of a pediatric urologist trained in minimally invasive and oncologic surgery as primary surgeon with an adult minimally invasive oncologic urologist as proctor. Key aspects for translation to the pediatric setting included: port placement, lower insufflation pressure, choice and size of instruments and supplies, and minimization of potential hemorrhage and ischemia with selective clamping/early unclamping technique. This approach was applied to a 14 kilogram, 3 year old female with a right lower pole lesion with cystic and solid components, concerning for malignancy. RESULTS: The mass was resected with negative margins and demonstrated benign pathology. Clamp time was 14 minutes, and EBL was minimal. There were no intraor post-operative complications. The patient’s creatinine was unchanged, and a follow-up ultrasound demonstrated no residual mass in a normal appearing right kidney. CONCLUSIONS: Collaboration of experienced pediatric and robotic teams allows for successful adaptation of adult techniques to pediatric patients. Specific considerations must be made in order to achieve safety and feasibility of RPN with selective clamping for renal preservation in cases of pediatric renal masses.