Determining the Safety Threshold for the Passage of a Ureteral Access Sheath in Clinical Practice Using a Purpose-Built Force Sensor.

PURPOSE: Ureteral injury is a frequent complication of ureteral access sheath deployment. We sought to define the safe threshold of force for the passage of a ureteral access sheath using a novel ureteral access sheath force sensor. MATERIALS AND METHODS: Ureteral access sheath-force sensor measurements were recorded in 210 renal units. A 16Fr ureteral access sheath was deployed initially based on a prior porcine study. If 6 N was reached, the surgeon was advised to downsize the 16Fr ureteral access sheath. In each case, a post-ureteroscopic lesion scale was recorded. Regression models were used to estimate the impact of adjusted variables on post-ureteroscopic lesion scale grade, 16Fr ureteral access sheath deployment, and peak force. RESULTS: A 16Fr ureteral access sheath was deployed in 127 (61%) renal units with a mean peak force of 5.7 N. Two high-grade ureteral injuries occurred; in both cases >6 N of force was recorded. Post-ureteroscopic lesion scale grade correlated directly with peak insertion force (p <0.01). Bacteriuria within 60 days of the procedure (OR 2.009, p=0.034), combination of preoperative stent plus oral tamsulosin (OR 2.998, p=0.045), and prior ipsilateral stone surgery (OR 2.13, p=0.01) were independent predictors of successful 16Fr ureteral access sheath deployment. Among patients with neither prior ipsilateral stone surgery nor preoperative stent, preoperative tamsulosin facilitated passage of a 16Fr ureteral access sheath (OR 2.750, p=0.034). CONCLUSIONS: Ureteral access sheath associated ureteral injury can be averted by limiting the insertion force to ≤6 N. Prior stone surgery, preoperative indwelling ureteral stent plus oral tamsulosin, and recently treated bacteriuria favored passage of a 16Fr ureteral access sheath. In the naïve, unstented patient, preoperative tamsulosin favored deployment of a 16Fr ureteral access sheath.

Surface-Treated Pellethanes: Comparative Quantification of Encrustation in Artificial Urine Solution.

Introduction: Encrustation of implanted urinary tract devices is associated with significant morbidity. Pellethane® is a polyether-based compound noted for its strength, porosity, and resistance to solvents. We assessed Pellethane thermoplastic polyurethane (TPU) with and without surface coatings 2-hydroxyethyl methacrylate (HEMA) and tetraethylene glycol dimethyl ether (TETRA) for the potential to resist encrustation in an artificial urine environment. Materials and Methods: Samples of Pellethane TPU, HEMA Pellethane TPU, TETRA Pellethane TPU, and hydrogel-coated ureteral stent (Cook®) were suspended in a batch-flow model with an artificial urine solution (AUS). Every 48 hours for 90 days, 40% of the solution was replaced with fresh AUS. All samples were stored in a 37°C incubator. Subsequently, the samples were thoroughly dried for 48 hours before weighing. Scanning electron microscopy was used to assess the degree of encrustation. Nu-Attom Inductively Coupled Plasma Mass Spectrometry (ICP-MS) was used to determine the precise compositions of the encrustation specifically with regard to calcium, magnesium, and phosphate. Results: At the conclusion of the 90-day trial, the samples were analyzed, and the average mass changes were as follows: stent 63.78%, uncoated Pellethane TPU 11.50%, HEMA-coated Pellethane TPU 2.90%, and TETRA-coated Pellethane TPU 0.60%. Pellethane TPU products, and specifically those coated with HEMA and TETRA, exhibited less average mass increase and a lesser propensity to form encrustation than the traditional urinary tract stent. The mass increases noted on coated Pellethane devices were primarily ionic, whereas that of the stent was not. Conclusion: Pellethane, particularly with an HEMA-based preventative coating, may serve as a favorable alternative to traditional urinary stent material, providing its improved resistance to encrustation.

Prospective Randomized Comparison of Standard Hand Pump Infuser Irrigation vs an Automated Irrigation Pump During Percutaneous Nephrolithotomy and Ureteroscopy: Assessment of Operating Room Efficiency and Surgeon Satisfaction.

Introduction: The objective of this study was to determine if use of an automated irrigation pump (AIP) during ureteroscopy (URS) and percutaneous nephrolithotomy (PCNL) affects circulating nurse labor, irrigation-related issues, and surgeon and nurse satisfaction when compared to manual hand pump (HP) irrigation. Methods: Eighty consecutive adult patients undergoing unilateral URS or PCNL were prospectively randomized to irrigation with the HP or AIP. Preoperative pump setup time, intraoperative pump maintenance time, total pump time (setup+maintenance), and the number of irrigation-related concerns verbalized by the surgeon intraoperatively were recorded; postoperatively, surgeons and nurses rated their satisfaction with the irrigation system (1 = highly dissatisfied to 10 = highly satisfied). Results: Eighty patients were enrolled (39 AIP and 41 HP); 51 patients underwent URS and 29 patients underwent PCNL. On univariate analysis, the AIP resulted in a significantly reduced total pump time for URS (2.9 vs 5.9 minutes) and PCNL (4.6 vs 33.9 minutes; p < 0.001). The number of irrigation-related concerns was significantly lower in the AIP group during URS (1.2 vs 2.8, p < 0.001), but not during PCNL (1.9 vs 4.0, p = 0.07). The AIP was associated with significantly higher nurse satisfaction during URS (9.2/10 vs 6.5/10, p < 0.001) and PCNL (9.4/10 vs 4.4/10, p = 0.001). There was no significant association between pump type and surgeon satisfaction. On multivariate analysis of URS cases controlling for body mass index and number of stones, use of the AIP was a predictor of total pump time <5 minutes (odds ratio 25.8, 95% confidence interval [CI] 4.0-165.4; p < 0.001) and favorable (8-10/10) nurse satisfaction rating (odds ratio 25.4, 95% CI 4.1-164.0; p < 0.001). Operative time, stone-free rate, and liters of irrigant used with the HP and AIP were similar. Conclusions: During URS and PCNL, the AIP was associated with a significant reduction in irrigation pump time and higher nurse satisfaction.

Smartphone technology and its applications in urology: a review of the literature.

PURPOSE: Smartphone technology has propelled the evolution of health-related mobile technology, referred to as mobile health (mHealth). With the rise of smartphone ownership and the growing popularity of health-related smartphone usage, mHealth offers potential benefits for both patients and health care providers. The objective of this review is to assess the current state of smartphone technology in urology. METHODS: A literature search of PubMed database was conducted to identify articles reporting on smartphone technology in urology. Publications were included if they focused on smartphone mHealth technology pertinent to the field of urology or included an evaluation of urological applications in digital stores. RESULTS: We identified 50 publications focused on the use of smartphones in urology. Studies were then grouped into the following categories: smartphones employing the built-in camera and light source, applications specific to prostate cancer, urolithiasis, pediatric urology, and as educational tools for urologists. In 23/50 (46%) studies, smartphone technology/intervention was compared to a control group or to standard of care. In this regard, smartphone technology did not demonstrate benefit over standard of care in 13 studies. In contrast, in 10 studies, smartphone interventions were proven beneficial over current practice. CONCLUSIONS: Smartphone technology is constantly evolving and has the potential to improve urological care and education. Of concern to consumer and urologist alike is that these downloadable programs are limited due to the accuracy of their content, risk of confidentiality breach, and the lack of central regulation and professional involvement in their development.

Reducing kidney motion: optimizing anesthesia and combining respiratory support for retrograde intrarenal surgery: a pilot study.

BACKGROUND: One of the greatest challenges presented with RIRS is the potential for movement of the stone within the operative field associated with diaphragm and chest respiratory excursions due to mechanical ventilation. To overcome this challenge, we propose in this pilot study a new general anesthesia technique combining high frequency jet ventilation (HFJV) with small volume mechanical ventilation (SVMV). Data regarding safety, feasibility and surgeons' impression was assessed. METHODS: Patients undergoing RIRS for kidney stones from November 2017 to May 2018 were prospectively recruited to participate in the study. In each case after the beginning of general anesthesia (GA) with mechanical ventilation (MV) surgeons were asked to assess the mobility of the operative field and conditions for laser lithotripsy according to the developed questionnaire scale. The questionnaire consisted of 5 degrees of assessment of kidney mobility and each question was scored from 1 to 5, 1 being very mobile (extremely poor conditions for dusting) and 5 completely immobile (Ideal conditions for dusting). After the assessment GA was modified with combined respiratory support (CRS), reducing tidal volume and respiratory rate (small volume mechanical ventilation, SVMV) and applying in the same time transcatheter high frequency jet ventilation (HFJV) inside the closed circuit. After beginning of CRS, surgeons were once again asked to assess the mobility of the operative field and the conditions for laser lithotripsy. Main ventilation parameters were recorded and compared in both regimens. RESULTS: A total of 38 patients were included in the study. The mean age was 49 (range 45-53) with a mean stone size of 10 mm (range 10-14) and Hounsfield unit of 1060 (range 930-1190). All patients underwent successful RIRS and no intraoperative complications occurred throughout the duration of the study. A statistically significant difference between ventilation parameters prior to and after CRS institution was detected in all cases, however their clinical impact was negligible. Despite this, assessment via the questionnaire scale point values varied significantly before and after the application of CRS and were 2.3 (2.1; 2.6) and 3.8 (3.7; 4.0) respectively (p < 0.001). CONCLUSIONS: The novel combined respiratory approach consisting of HFJV and SVMV appears to provide better conditions for stone dusting through reduced respiratory kidney motion and is not associated with adverse health effects or complications. TRIAL REGISTRATION: NCT03999255 , date of registration: 25th June 2019 (retrospectively registered).

Endockscope: A Disruptive Endoscopic Technology.

Objective: To assess optical performance and diagnostic capability of the Endockscope system (ES) vs the standard endoscopic system (SES) using four rigid/semi-rigid endoscopes. The ES combines a smartphone, lens system, and a rechargeable light-emitting diode (LED) light source to provide a low-cost alternative ($45) to the standard camera and high-powered light source ($45,000) used in endoscopic procedures. Materials and Methods: Video clips (<20 seconds) of standard rigid nephroscopy, semi-rigid ureteroscopy, rigid cystoscopy, and laparoscopy in two adult male cadavers were recorded using the ES combined with either the Apple iPhone X or Samsung Galaxy S9+ and also with the high-definition SES (Karl Storz). Sixteen urologists blinded to the camera modality assessed the image resolution, brightness, color, sharpness, and overall quality using a Likert-type scale; acceptability for diagnostic purposes was judged on a binary scale (yes/no). Results: For rigid cystoscopy, there was no statistical difference between both ES systems and the SES. For semi-rigid ureteroscopy the two ES systems performed equal to or better than the SES. For rigid nephroscopy, the ES plus Galaxy was comparable to the SES, except in brightness (p < 0.05), whereas the ES plus iPhone was inferior in various parameters. For laparoscopy, the ES plus Galaxy was inferior to the SES in brightness and overall quality (p < 0.05); the ES plus iPhone was inferior for all laparoscopic image parameters compared with the SES. For diagnostic purposes, the ES plus Galaxy was equivalent to the SES for all endoscopes; the ES plus iPhone was equivalent to the SES for cystoscopy, ureteroscopy, and nephroscopy. Conclusion: The ES plus the Apple iPhone X or Samsung Galaxy S9+ offers comparable imaging and provides diagnostic information equivalent to the standard system for rigid endoscopy of the kidney, ureter, and bladder; the Galaxy S9+ provides comparable imaging and diagnostic capabilities for evaluation of the abdomen.

Evaluation of Urology Residency Training and Perceived Resident Abilities in the United States.

OBJECTIVE: To identify differences and potential deficiencies in urology residency training programs in the United States as they are perceived by residents/recent graduates and program directors. MATERIALS AND METHODS: A 45-question and 38-question survey was sent to chief residents/recent graduates and program directors, respectively, at all 120 US urology programs regarding prior medical education, urologic training curricula, and perceived surgical proficiency, among other topics. RESULTS: Survey response rate was 58% and 52% for residents and program directors, respectively. Responses regarding program characteristics (e.g., salary, vacation) and research training were similar between program directors and residents. However, their responses regarding skills training and subspecialty training (e.g., robotics and pediatrics) differed substantially. Program directors reported the availability of advanced skills trainers (robot-88%, laparoscopic-86%), whereas fewer residents felt they were available (robot 54% and laparoscopic 72%). The same discrepancies persisted with questions about subspecialty exposure (e.g., program directors reported 48% renal transplant experience vs. 13% reported by residents). Most residents felt comfortable performing essential urology procedures (e.g., cystoscopy/ureteroscopy, open nephrectomy). In contrast, the majority expressed a lack of confidence in performing unsupervised advanced minimally invasive procedures (e.g., laparoscopic and robotic partial nephrectomy, endopyelotomy). Among the responding residents, 72% pursued fellowship training; nearly two-thirds of these residents chose to enter fellowship in order to overcome perceived training deficiencies. CONCLUSIONS: Program directors and residents have differing perceptions regarding the education and resources associated with US urology residency training programs. US graduates of urology residency programs express a perceived lack of confidence in several procedures that are commonly encountered in a general urologic practice.