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  • To stage or not to stage?-A cost minimization analysis of sacral neuromodulation placement strategies. Neurourology and urodynamics Sun, A. J., Harris, C. R., Comiter, C. V., Elliott, C. S. 2019

    Abstract

    AIMS: Sacral neuromodulation (SNM) is a standard therapy for refractory overactive bladder (OAB). Traditionally, SNM placement involves placement of an S3 lead with 1-3 weeks of testing before considering a permanent implant. Given the potential risk of bacterial contamination during testing and high success rates published by some experts, we compared the costs of traditional 2-stage against single-stage SNM placement for OAB.METHODS: We performed a cost minimization analysis using published data on 2-stage SNM success rates, SNM infection rates, and direct reimbursements from Medicare for 2017. We compared the costs associated with a 2-stage vs single-stage approach. We performed sensitivity analyses of the primary variables listed above to assess where threshold values occurred and used separate models for freestanding ambulatory surgery centers (ASC) and outpatient hospital departments (OHD).RESULTS: Based on published literature, our base case assumed a 69% SNM success rate, a 5% 2-stage approach infection rate, a 1.7% single-stage approach infection rate, and removal of 50% of non-working single-stage SNMs. In both ASC ($17613 vs $18194) and OHD ($19832 vs $21181) settings, single-stage SNM placement was less costly than 2-stage placement. The minimum SNM success rates to achieve savings with a single-stage approach occur at 65.4% and 61.3% for ASC and OHD, respectively.CONCLUSIONS: Using Medicare reimbursement, single-stage SNM placement is likely to be less costly than 2-stage placement for most practitioners. The savings are tied to SNM success rates and reimbursement rates, with reduced costs up to $5014 per case in centers of excellence (?90% success).

    View details for DOI 10.1002/nau.24075

    View details for PubMedID 31215706

  • The Impact of Clostridium Histolyticum Collagenase on the Prevalence and Management of Peyronie's Disease in the United States WORLD JOURNAL OF MENS HEALTH Sun, A. J., Li, S., Eisenberg, M. L. 2019; 37 (2): 234?39
  • TO STAGE OR NOT TO STAGE? - A COST MINIMIZATION ANALYSIS OF SACRAL NEUROMODULATION PLACEMENT STRATEGIES Sun, A., Harris, C., Comiter, C., Elliott, C. LIPPINCOTT WILLIAMS & WILKINS. 2019: E1187
  • PATERNAL MEDICATION USE AND COMORBIDITY IN THE UNITED STATES: A REVIEW OF OVER 1 MILLION LIVE BIRTHS Sun, A., Li, S., Zhang, C., Eisenberg, M. LIPPINCOTT WILLIAMS & WILKINS. 2019: E556?E557
  • To stage or not to stage?-a cost minimization analysis of sacral neuromodulation placement strategies Sun, A., Harris, C., Comiter, C. V., Elliott, C. S. WILEY. 2019: S159?S160
  • Prevalence of twenty-four hour urine testing in Veterans with urinary stone disease. PloS one Ganesan, C., Thomas, I. C., Song, S., Sun, A. J., Sohlberg, E. M., Kurella Tamura, M., Chertow, G. M., Liao, J. C., Conti, S., Elliott, C. S., Leppert, J. T., Pao, A. C. 2019; 14 (8): e0220768

    Abstract

    The American Urological Association guidelines recommend 24-hour urine testing in patients with urinary stone disease to decrease the risk of stone recurrence; however, national practice patterns for 24-hour urine testing are not well characterized. Our objective is to determine the prevalence of 24-hour urine testing in patients with urinary stone disease in the Veterans Health Administration and examine patient-specific and facility-level factors associated with 24-hour urine testing. Identifying variations in clinical practice can inform future quality improvement efforts in the management of urinary stone disease in integrated healthcare systems.We accessed national Veterans Health Administration data through the Corporate Data Warehouse (CDW), hosted by the Veterans Affairs Informatics and Computing Infrastructure (VINCI), to identify patients with urinary stone disease. We defined stone formers as Veterans with one inpatient ICD-9 code for kidney or ureteral stones, two or more outpatient ICD-9 codes for kidney or ureteral stones, or one or more CPT codes for kidney or ureteral stone procedures from 2007 through 2013. We defined a 24-hour urine test as a 24-hour collection for calcium, oxalate, citrate or sulfate. We used multivariable regression to assess demographic, geographic, and selected clinical factors associated with 24-hour urine testing.We identified 130,489 Veterans with urinary stone disease; 19,288 (14.8%) underwent 24-hour urine testing. Patients who completed 24-hour urine testing were younger, had fewer comorbidities, and were more likely to be White. Utilization of 24-hour urine testing varied widely by geography and facility, the latter ranging from 1 to 40%.Fewer than one in six patients with urinary stone disease complete 24-hour urine testing in the Veterans Health Administration. In addition, utilization of 24-hour urine testing varies widely by facility identifying a target area for improvement in the care of patients with urinary stone disease. Future efforts to increase utilization of 24-hour urine testing and improve clinician awareness of targeted approaches to stone prevention may be warranted to reduce the morbidity and cost of urinary stone disease.

    View details for DOI 10.1371/journal.pone.0220768

    View details for PubMedID 31393935

  • Giant renal angiomyolipoma in a solitary kidney. The Canadian journal of urology Sohlberg, E., Sun, A., Massoudi, R., Prado, K., Skinner, E. 2018; 25 (6): 9614?16

    Abstract

    While renal angiomyolipomas (AMLs) generally remain small and asymptomatic, larger AMLs are more common in tuberous sclerosis patients. Giant AMLs over 20 cm are a rare entity and little is known about their management. We present a unique case of a 48-year-old woman with tuberous sclerosis and a 39 cm AML arising from a solitary kidney, after undergoing nephrectomy for a prior AML. Giant renal AMLs can occur in patients with tuberous sclerosis and resection should be considered even for large tumors. Renal sparing is often difficult and patients should be counseled about potential need for postoperative hemodialysis.

    View details for PubMedID 30553288

  • The Impact of Clostridium Histolyticum Collagenase on the Prevalence and Management of Peyronie's Disease in the United States. The world journal of men's health Sun, A. J., Li, S., Eisenberg, M. L. 2018

    Abstract

    PURPOSE: We evaluated the impact of collagenase clostridium histolyticum (CCH) on rates of diagnosis, treatment, and corporal rupture in Peyronie's disease (PD). We examined the impact of CCH on cost of PD treatment.MATERIALS AND METHODS: We extracted data on PD diagnosis (ICD-9 607.95 and ICD-10 N48.6), corporal rupture (ICD-9 959.13 and ICD-10 S39.840A), CCH use (J0775), penile injections (CPT 54200), and corporal rupture repair from 2008 to 2016 in men over 40 years old using the Clinformatics Data Mart Database (3.7 to 4.9 million males). We analyzed for prevalence of PD, rates of PD treatments, cost associated with treatment, and rates of corporal rupture and repair by year.RESULTS: The prevalence of PD was 0.29% in 2013 and did not increase after CCH entered the market in 2014. An average of 2.52% of men with PD received treatment before CCH, compared with 3.75% after (p<0.0001). Penile injection rates increased (1.34% vs. 2.61%, p<0.0001), while rates of surgical treatments decreased between these periods. There was no change in rate of corporal rupture in men with PD before (0.024%) and after (0.024%) CCH. Overall, only 20.0% of corporal ruptures were repaired. After CCH entered practice, a significant increase in cost occurred (p=0.013).CONCLUSIONS: The prevalence of men with PD did not change after CCH. However, more men with PD received treatment due to an increase in penile injections. The cost of treating PD increased after CCH became available. The overall prevalence of corporal rupture did not change after CCH entered the market.

    View details for PubMedID 30588781

  • The cost of a catheter: An environmental perspective on single use clean intermittent catheterization. Neurourology and urodynamics Sun, A. J., Comiter, C. V., Elliott, C. S. 2018

    Abstract

    METHODS: We estimated the prevalence of CIC use in the United States using a neurogenic population, consisting of persons with multiple sclerosis, spina bifida, and spinal cord injury. We measured catheter samples to obtain the amount of waste per catheter.RESULTS: At least 300800 persons in the United States perform CIC for neurogenic bladder management. Assuming five catheterization events per day, the amount of waste generated by single-use CIC is between 26500 to 235400 pounds or 22600 to 564000 liters per day, depending on catheter model.CONCLUSIONS: Single-use CIC may generate up to 85 million pounds or 206 million liters of waste annually, equivalent to more than 26000 cars or 80 Olympic-sized swimming pools. Laid end-to-end, there is enough catheter length circumscribe the world more than 5.5 times. The most common materials used in catheter construction have little to no degradation once in a landfill. Given the unproven clinical benefit of single-use catheterization, the environmental impact and alternatives should be considered.

    View details for PubMedID 30106190

  • Registries and Databases in Sexual Medicine: Utility? JOURNAL OF SEXUAL MEDICINE Sun, A. J., Eisenberg, M. L. 2018; 15 (4): 426?27

    View details for PubMedID 29609911

  • PEYRONIE'S DISEASE: THE IMPACT OF COLLAGENASE CLOSTRIDIUM HISTOLYTICUM ON DIAGNOSIS, TREATMENT, AND COST Sun, A., Li, S., Eisenberg, M. ELSEVIER SCIENCE INC. 2018: E883
  • PREOPERATIVE KIDNEY FUNCTION TRENDS: IMPROVING ESTIMATES OF BASELINE KIDNEY FUNCTION PRIOR TO KIDNEY CANCER SURGERY Sun, A., Thomas, C., Ganesan, C., Sylman, J., Pao, A., Wagner, T., Brooks, J., Chertow, G., Leppert, J. ELSEVIER SCIENCE INC. 2018: E362
  • Night-time communication at Stanford University Hospital: perceptions, reality and solutions BMJ QUALITY & SAFETY Sun, A., Wang, L., Go, M., Eggers, Z., Deng, R., Maggio, P., Shieh, L. 2018; 27 (2): 156?62

    Abstract

    Resident work hour restrictions have led to the creation of the 'night float' to care for the patients of multiple primary teams after hours. These residents are often inundated with acute issues in the numerous patients they cover and are less able to address non-urgent issues that arise at night. Further, non-urgent pages may contribute to physician alarm fatigue and negatively impact patient outcomes.To delineate the burden of non-urgent paging at night and propose solutions.We performed a resident review and categorisation of 1820 pages to night floats between September 2014 and December 2014. Both attending and nursing review of 10% of pages was done and compared.Of reviewed pages, 62.1% were urgent and 27.7% were non-urgent. Attending review of random page samples correlated well with resident review. Common reasons for non-urgent pages were non-urgent patient status updates, low-priority order requests and non-critical lab values.A significant number of non-urgent pages are sent at night. These pages likely distract from acute issues that arise at night and place an unnecessary burden on night floats. Both behavioural and systemic adjustments are needed to address this issue. Possible interventions include integrating low-priority messaging into the electronic health record system and use of charge nurses to help determine urgency of issues and batch non-urgent pages.

    View details for PubMedID 29055898

  • Association Between Marijuana Use and Sexual Frequency in the United States: A Population-Based Study JOURNAL OF SEXUAL MEDICINE Sun, A. J., Eisenberg, M. L. 2017; 14 (11): 1342?47

    Abstract

    Marijuana use is increasingly prevalent in the United States. Effects of marijuana use on sexual function are unclear, with contradictory reports of enhancement and detriment existing.To elucidate whether a relation between marijuana use and sexual frequency exists using a nationally representative sample of reproductive-age men and women.We analyzed data from cycle 6 (2002), cycle 7 (2006-2010), and continuous survey (2011-2015) administrations of the National Survey of Family Growth, a nationally representative cross-sectional survey. We used a multivariable model, controlling for demographic, socioeconomic, and anthropographic characteristics, to evaluate whether a relationship between marijuana use and sexual frequency exists.Sexual frequency within the 4 weeks preceding survey administration related to marijuana use and frequency in the year preceding survey administration.The results of 28,176 women (average age = 29.9 years) and 22,943 men (average age = 29.5) were analyzed. More than 60% of men and women were Caucasian, and 76.1% of men and 80.4% of women reported at least a high school education. After adjustment, female monthly (incidence rate ratio [IRR] = 1.34, 95% CI = 1.07-1.68, P = .012), weekly (IRR = 1.36, 95% CI = 1.15-1.60, P < .001), and daily (IRR = 1.16, 95% CI = 1.01-1.32, P = .035) marijuana users had significantly higher sexual frequency compared with never users. Male weekly (IRR = 1.22, 95% CI = 1.06-1.41, P = .006) and daily (IRR = 1.36, 95% CI = 1.21-1.53, P < .001) users had significantly higher sexual frequency compared with never users. An overall trend for men (IRR = 1.08, 95% CI = 1.05-1.11, P < .001) and women (IRR = 1.07, 95% CI = 1.04-1.10, P < .001) was identified showing that higher marijuana use was associated with increased coital frequency.Marijuana use is independently associated with increased sexual frequency and does not appear to impair sexual function.Our study used a large well-controlled cohort and clearly defined end points to describe a novel association between marijuana use and sexual frequency. However, survey responses were self-reported and represent participants only at a specific point in time. Participants who did not answer questions related to marijuana use and sexual frequency were excluded.A positive association between marijuana use and sexual frequency is seen in men and women across all demographic groups. Although reassuring, the effects of marijuana use on sexual function warrant further study. Sun AJ, Eisenberg ML. Association Between Marijuana Use and Sexual Frequency in the United States: A Population-Based Study. J Sex Med 2017;14:1342-1347.

    View details for PubMedID 29110804

  • Venous thromboembolism following radical cystectomy: significant predictors, comparison of different anticoagulants and timing of events. The Journal of urology Sun, A. J., Djaladat, H., Schuckman, A., Miranda, G., Cai, J., Daneshmand, S. 2015; 193 (2): 565?69

    Abstract

    We determined the rate, timing and predictors of venous thromboembolism after open radical cystectomy for urothelial bladder cancer. We also compared the use of warfarin (1971 to 2008) and unfractionated heparin (2008 to 2012) as prophylaxis.We retrospectively reviewed the records of 2,316 patients who underwent open radical cystectomy and extended pelvic lymph node dissection for urothelial bladder cancer with intent to cure at our institution between 1971 and 2012. The rate and timing of symptomatic venous thromboembolism that developed within 3 months of surgery was calculated in the cohort. Multivariate stepwise logistic regression was used to find significant predictors of symptomatic venous thromboembolism and compare the warfarin based and heparin based prophylaxis protocols.A total of 109 symptomatic venous thromboembolism cases developed for a rate of 4.7%, including 2.1% for deep vein thrombosis and 2.6% for pulmonary embolism. Of these cases 57.8% developed after discharge home at a median of 20 days postoperatively (range 2 to 91). Four significant predictors of venous thromboembolism were identified, including body mass index (p = 0.0015), surgical margins (p = 0.025), diversion type (p = 0.023) and hospitalization duration (p <0.0001). Use of prophylactic heparin vs warfarin was not a significant predictor (p = 0.31).Venous thromboembolism remains a significant complication of open radical cystectomy. Using an in-house, heparin based anticoagulation protocol consistent with current AUA (American Urological Association) guidelines has not decreased the rate of venous thromboembolism compared to historical warfarin use. On closer evaluation most venous thromboembolism cases in our population occurred after discharge home. Future studies are needed to establish the benefits of extended duration venous thromboembolism prophylaxis regimens that cover the critical post-hospitalization period.

    View details for DOI 10.1016/j.juro.2014.08.085

    View details for PubMedID 25150642

  • Novel training methods for robotic surgery. Indian journal of urology : IJU : journal of the Urological Society of India Sun, A. J., Aron, M., Hung, A. J. 2014; 30 (3): 333?38

    Abstract

    The objectives of this review are to summarize the current training modalities and assessment tools used in urological robotic surgery and to propose principles to guide the formation of a comprehensive robotics curriculum.The PUBMED database was systematically searched for relevant articles and their citations utilized to broaden our search. These articles were reviewed and summarized with a focus on novel developments.A multitude of training modalities including didactic, dry lab, wet lab, and virtual reality have been developed. The use of these modalities can be divided into basic skills-based exercises and more advanced procedure-based exercises. Clinical training has largely followed traditional methods of surgical teaching with the exception of the unique development of tele-mentoring for the da Vinci interface. Tools to assess both real-life and simulator performance have been developed, including adaptions from Fundamentals of Laparoscopic Surgery and Objective Structured Assessment of Technical Skill, and novel tools such as Global Evaluative Assessment of Robotic Skills.The use of these different entities to create a standardized curriculum for robotic surgery remains elusive. Selection of training modalities and assessment tools should be based upon performance data-based validity and practical feasibility. Comparative assessment of different modalities (cross-modality validity) can help strengthen the development of common skill sets. Constant data collection must occur to guide continuing curriculum improvement.

    View details for DOI 10.4103/0970-1591.128506

    View details for PubMedID 25097322

    View details for PubMedCentralID PMC4120223

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