Trends and patterns of initial percutaneous nephrolithotomy and subsequent procedures among commercially-insured US adults with urinary system stone disease: a 10-year population-based study.

PURPOSE: To describe trends and patterns of initial percutaneous nephrolithotomy (PCNL) and subsequent procedures from 2010 to 2019 among commercially-insured US adults with urinary system stone disease (USSD). METHODS: Retrospective study of administrative data from the IBM® MarketScan® Database. Eligible patients were aged 18-64 years and underwent PCNL between 1/1/2010 and 12/31/2019. Measures of interest for analysis of trends and patterns included the setting of initial PCNL (inpatient vs. outpatient), percutaneous access (1 vs. 2-step), and the incidence, time course, and type of subsequent procedures (extracorporeal shockwave lithotripsy [SWL], ureteroscopy [URS], and/or PCNL) performed up-to 3 years after initial PCNL. RESULTS: A total of 8,348 patients met the study eligibility criteria. During the study period, there was a substantial shift in the setting of initial PCNL, from 59.9% being inpatient in 2010 to 85.3% being outpatient by 2019 (P < 0.001). The proportion of 1 vs. 2-step initial PCNL fluctuated over time, with a low of 15.1% in 2016 and a high of 22.0% in 2019 but showed no consistent yearly trend (P = 0.137). The Kaplan-Meier estimated probability of subsequent procedures following initial PCNL was 20% at 30 days, 28% at 90 days, and 50% at 3 years, with slight fluctuations by initial PCNL year. From 2010 to 2019, the proportion of subsequent procedures accounted for by URS increased substantially (from 30.8 to 51.8%), whereas SWL decreased substantially (from 39.5 to 14.7%) (P < 0.001). CONCLUSIONS: From 2010 to 2019, PCNL procedures largely shifted to the outpatient setting. Subsequent procedures after initial PCNL were common, with most occurring within 90 days. URS has become the most commonly-used subsequent procedure type.

Risk factors for recurrent percutaneous nephrostomy catheter-related infections.

PURPOSE: Percutaneous nephrostomy (PCN) catheters are mainly indicated for urinary tract obstructions. Unfortunately, the rate for infection and recurrence remains elevated. Our objective was to identify the risk factors leading to recurrent PCN-related infections (PCNI) in cancer patients. METHODS: We retrospectively reviewed 571 patients who underwent initial PCN catheter placement at our institution. Of these, we identified patients with a definite PCNI and catheter exchange, with a minimum 30-day follow-up. We defined PCNI as presence of a urine culture positive for bacteria (≥ 104 CFU/mL) plus symptoms of urinary tract infection. A PCNI was considered recurrent if the same organism was isolated. Antibiotics were considered concordant if they were active against all identified organisms. RESULTS: A total of 81 patients (14%) developed an initial PCNI. Of 47 patients with 30-day follow-up, 10 patients (21%) were identified as having a recurrent PCNI. In terms of demographic characteristics, clinical manifestations, and microbiological data, there was no statistically significant difference between the recurrent and non-recurrent groups. However, in multivariate logistic regression analysis, two factors were independently associated with a decrease in recurrent PCNI: concordant antibiotic use (OR 0.04; p = 0.008) and PCN catheter exchange within 4 days of infection (OR 0.1; p = 0.048). CONCLUSIONS: To decrease the high rate of recurrent infections, associated costs, and potential delay in further chemotherapy, we recommend that once antimicrobial susceptibility test results are available and the patient is known to be receiving concordant antimicrobials, clinicians proceed with immediate PCN catheter exchange, ideally within the first 4 days of the infection.

Trans-tract electrocoagulation can decrease the need for postoperative nephrostomy tube after endoscopic combined intrarenal surgery.

AIM: To assess the efficacy and safety of trans-tract electrocoagulation at the end of endoscopic combined intrarenal surgery for renal or ureteral stones. METHODS: The present study included patients who underwent endoscopic combined intrarenal surgery from May 2010 to March 2018. After June 2013, the trans-tract electrocoagulation procedure, to coagulate bleeding from the access tract using a resectscope was carried out at the end of the operation. We compared the patients' background and surgical outcomes between patients with and without trans-tract electrocoagulation. RESULTS: Between the trans-tract electrocoagulation (n = 225) and non-trans-tract electrocoagulation (n = 72) groups, the stone number was significantly smaller (1:2:3 or more, 126:72:27 vs 59:10:3, P = 0.001) and the initial stone-free rates were significantly higher (80% vs 72%, P = 0.006) in the trans-tract electrocoagulation group than in the non-trans-tract electrocoagulation group. Patients experienced a higher nephrostomy tube-free rate (67% vs 26%, P < 0.0001), shorter postoperative catheterization time (2.8 ± 3.8 vs 5.4 ± 5.0 days, P = 0.002) and shorter hospital stay (6.5 ± 3.6 vs 8.8 ± 5.0 days, P = 0.0001) in the trans-tract electrocoagulation group than in the non-trans-tract electrocoagulation group. CONCLUSIONS: Trans-tract electrocoagulation in endoscopic combined intrarenal surgery is a safe and efficient procedure that decreases the need for nephrostomy tube placement after surgery.

Comparison of super-mini PCNL (SMP) versus Miniperc for stones larger than 2 cm: a propensity score-matching study.

PURPOSE: To compare the efficacy and safety of Super-mini percutaneous nephrolithotomy (SMP, F12-F14) and Miniperc (F18) in the treatment of renal stones of 2-4 cm in size. METHODS: A prospective comparative analysis of outcomes of patients who underwent SMP and Miniperc for treatment of 2-4 cm renal stones was conducted between July 2014 and January 2017. Demographic data, stone criteria, operative technique, complications, blood transfusion, hemoglobin decrease, stone-free rate (SFR) and length of hospital stay were compared between the two groups. Propensity score-matching (PSM) analysis was performed to further compare the outcomes between the two groups. RESULTS: 79 and 257 patients underwent SMP and Miniperc, respectively. After matching, 73 patients in each group were included. The stone burden was comparable for both groups (3.0 ± 1.1 vs 3.2 ± 0.7 cm, p = 0.577). Mean operation time was not significant different between two groups (p = 0.115), while the hospital stay of SMP was much shorter than Miniperc (2.6 ± 1.4 vs 5.2 ± 1.8, p < 0.0001). Both groups had similar SFRs in postoperative 1 day and at 1 month follow-up (p = 0.326, p = 0.153), while SMP achieved a markedly higher tubeless rate than Miniperc (84.9 vs 47.9%, p < 0.0001). The total complication rate was significantly lower in SMP (16.4 vs 41.1%, p = 0.0001), and the SIRS rate was markedly lower in SMP group (1.4 vs 12.3%, p = 0.009). CONCLUSIONS: SMP is equally effective as Miniperc in the treatment of moderate renal calculi, and has the significant advantage in hospital duration and tubeless rate.

Surgical outcomes of percutaneous nephrolithotomy in 3402 patients and results of stone analysis in 1559 patients.

OBJECTIVE: To report our experience of a series of percutaneous nephrolithotomy (PCNL) procedures in a single centre over 18 years in terms of patient and stone characteristics, indications, stone clearance and complications, along with the results of chemical analysis of stones in a subgroup. PATIENTS AND METHODS: We retrospectively analysed the outcomes of PCNL in 3402 patients, who underwent the procedure between 1997 and 2014, obtained from a prospectively maintained database. Data analysis included patients' age and sex, laboratory investigations, imaging, punctured calyx, duration of operation, volume of irrigation fluid, radiation exposure time, blood transfusion, complications and stone-free status at 1-month follow-up. For the present analysis, outcomes in relation to complications and success were divided in two eras, 1997-2005 and 2006-2014, to study the differences. RESULTS: Of the 3402 patients, 2501 (73.5%) were male and 901 (26.5%) were female, giving a male:female ratio of 2.8:1. Staghorn (partial or complete) calculi were found in 27.5% of patients, while 72.5% had non-staghorn calculi. Intracorporeal energy sources used for stone fragmentation included ultrasonography in 917 patients (26.9%), pneumatic lithoclast in 1820 (53.5%), holmium laser in 141 (4.1%) and Lithoclast® master in 524 (15.4%). In the majority of patients (97.4%) a 18-22-F nephrostomy tube was placed after the procedure, while 69 patients (2.03%) underwent tubeless PCNL. The volume of the irrigation fluid used ranged from 7 to 37 L, with a mean of 28.4 L. The stone-free rate after PCNL in the first era studied was 78%, vs 83.2% in the second era, as assessed by combination of ultrasonography and plain abdominal film of the kidney, ureter and bladder. The complication rate in the first era was 21.3% as compared with 10.3% in the second era, and this difference was statistically significant. Stone analysis showed pure stones in 41% and mixed stones in 58% of patients. The majority of stones consisted of calcium oxalate. CONCLUSIONS: This is the largest series of PCNL reported from any single centre in Pakistan, where there is a high prevalence of stone disease associated with infective and obstructive complications, including renal failure. PCNL as a treatment method offers an economic and effective option in the management of renal stone disease with acceptable stone clearance rates in a resource-constrained healthcare system.

Effects of body mass index on the outcomes of percutaneous nephrolithotomy.

OBJECTIVE: To examine the the effect of body mass index (BMI) on PNL results and complications with a large number of patients. MATERIALS AND METHODS: A total of 958 patients were included in the study, who underwent percutaneous nephrolithotomy in our clinic between 2008 and 2015. Patients were divided into 2 groups according to their body mass index. Patients with a BMI < 30 kg/m2 were classified as group 1 (n:676) and patients with a BMI ≥ 30 kg/m2 were classified as group 2 (n:282). Achieving stone-free status or having residual stones of ≤ 4 mm were considered as operational success. RESULTS: The mean age was 47.9 years for group 1 and 48.9 years for group 2 patients. At postoperative first month CT analysis, residual stone was not observed in 466 patients (69%) of group 1 and 20 (72%) patients of group 2. There was no significant difference between the groups in terms of stone-free status (p=0.348). There was no significant difference between two groups complications. Also, there was no difference between the groups for requiring additional intervention (p=0.924). No other complications were observed in the patients. CONCLUSIONS: BMI does not affect the outcomes of percutaneous nephrolithotomy as well as complication rate.

Complications after prone PCNL in pediatric, adult and geriatric patients - a single center experience over 7 years.

INTRODUCTION: CROES-Clavien system (CCS) for grading complications in percutaneous nephrolithotomy (PCNL) is a step towards standardization of outcomes. We categorized complications based on CCS and predicted risk factors across the entire cohort and individually for pediatric (P: ≤18 years), adult (A: 19-65 years) and geriatric (G: ≥65 years) subgroups to assess the risk factors in each subset. We assessed association of complications with length of hospitalization (LOH) and operation time (OT). MATERIALS AND METHODS: Retrospective record review of unilateral PCNL performed between January 2009-September 2015 at a tertiary care center in India, performing around 150 PCNL per year. RESULTS: Out of 922 (P=61; A=794; G=67) PCNL, 259 (28.09%) complications occurred with CCS I, II, III and IV constituting 152 (16.49%), 72 (7.81%), 31 (3.36%) and 4 (0.43%) respectively and its distribution was similar across the subsets and majority (224; 24.3%) were minor (CCS-1, 2). Placement of a nephrostomy (47.4%; 18/38) in Group P, supracostal access, ≥2 punctures, higher GSS, nephrostomy, staghorn stones, ≥2 stones, stone size in Group A and hydronephrosis and prolonged OT in Group G were significantly associated with complications. On logistic regression, need of nephrostomy (adj. OR - 4.549), OT (adj. OR - 1.364) and supracostal access (adj. OR - 1.471) significantly contributed to complications in the study population. LOH was found to be significantly associated with complications (p<0.001). CONCLUSIONS: Contrary to the belief that extremes of ages are associated with complications of prone PCNL, we found age does not alter the incidence or grade of complications and LOH.

[Treatment of ureteral fistula and stricture following renal transplantation with Boari flap].

OBJECTIVE: To estimate the incidence rate of ureteral fistula and stricture after kidney transplantation, and to evaluate the effect of bladder flap (Boari flap) on ureteral complication of the transplanted kidney. 
 Methods: The clinical data and risk factors from 270 recipients of renal transplantation, who came from the Centre of Organ Transplantation, Xiangya Hospital, Central South University from January 2010 to January 2015, were retrospectively analyzed. The surgical management included Boari flap for ureteral reconstruction, neoureterocystostomy and endoscopic therapy with double-J (DJ) stent placement. Surgical proceeding and the effectiveness were evaluated.
 Results: The incidence rate of ureteral fistula following renal transplantation was 3.3%. The risk factors for ureteral fistula included elder donor age (P<0.05), delayed graft function (P<0.01), bladder spasm (P<0.05), and multiple renal arteries in allograft (P<0.01). Four cases were recovered after conservative treatment, and the other 5 cases were recovered after the treatment with Boari flap for ureteric reconstruction. The incidence rate of ureteral stricture was 4.4%. The risk factors for ureteral stricture included elder donor age (P<0.05), delayed graft function (P<0.05), cystospasm (P<0.05), ureteral fistula (P<0.01) and multiple renal arteries in allograft (P<0.01). Four cases underwent endoscopic therapy, 2 of them carried out percutaneous nephrostomy followed by antegrade DJ stent placement and the other 2 patients by retrograde DJ stent placement under ureteroscopy. Eight patients underwent surgery, 6 of them was treated by Boari flap for ureteral reconstruction and 2 patients were treated by neoureterocystostomy. All the patients recovered after surgical management.
 Conclusion: The ureteral complications after renal transplantation include ureteral fistula and stricture. Although the total incidence is low, the complications can result in adverse effects to the graft function and the life quality of the recipients. The risk factors for ureteral complication include elder donor age, delayed graft function, cystospasm, and multiple renal arteries in allograft. Ureteral fistula is the risk factor for ureteral fracture. Boari flap for ureterial reconstruction is an effective method in the treatment of the ureteral fistula and stricture.

Comparison of flexible ureterorenoscopy and mini-percutaneous nephrolithotomy in treatment of lower calyceal stones smaller than 2 cm.

To compare the outcomes of flexible ureterorenoscopy (F-URS) and mini-percutaneous nephrolithotomy (mini-PNL) in the treatment of lower calyceal stones smaller than 2 cm. Patients who underwent F-URS and mini-PNL for the treatment of lower calyceal stones smaller than 2 cm between March 2009 and December 2014 were retrospectively evaluated. Ninety-four patients were divided into two groups by treatment modality: F-URS (Group 1: 63 patients) and mini-PNL (Group 2: 31 patients). All patients were preoperatively diagnosed with intravenous pyelography or computed tomography. Success rates for F-URS and mini-PNL at postoperative first month were 85.7% and 90.3%, respectively. Operation time, fluoroscopy time, and hospitalization time for F-URS and mini-PNL patients were 44.40 min, 2.9 min, 22.4 h, and 91.9 min, 6.4 min, and 63.8 h, respectively. All three parameters were significantly shorter among the F-URS group (p < 0.001). Postoperative hemoglobin drop was significantly lower in F-URS group compared to mini-PNL group (0.39 mg/dL vs. 1.15 mg/dL, p = 0.001). A comparison of complications according to the Clavien classification demonstrated significant differences between the groups (p = 0.001). More patients in the F-URS groups require antibiotics due to urinary tract infection, and more patients in the mini-PNL group required ureteral double J catheter insertion under general anesthesia. Although both F-URS and mini-PNL have similar success rates for the treatment of lower calyceal stones, F-URS appears to be more favorable due to shorter fluoroscopy and hospitalization times; and lower hemoglobin drops. Multicenter and studies using higher patient volumes are needed to confirm these findings.

Comparative effectiveness and safety of various treatment procedures for lower pole renal calculi: a systematic review and network meta-analysis.

OBJECTIVE: To compare the effectiveness of various treatments used for lower pole renal calculi. METHODS: We searched PubMed, EMBASE, CINAHL, the Cochrane Collaboration's Database of Systematic Reviews, the Cochrane Collaboration Central Register of Controlled Clinical Trials as well as ClinicalTrials.gov for reports up to 1 April 2014. The search was supplemented with abstract reports from various urology conferences. All randomised, 'blinded' clinical studies including patients treated for lower pole renal calculi of <20 mm were included for review. Two authors independently reviewed 5 194 articles, and identified and selected 13 trials for analysis. Network meta-analysis was performed to generate comparative statistics, while quality was assessed with the Jadad composite scale and risk of bias. RESULTS: All treatment methods examined: percutaneous nephrolithotomy (PNL), ureterorenoscopy (URS) and extracorporeal shockwave lithotripsy (SWL) with an adjuvant therapy (such as inversion, hydration and forced diuresis) were more effective than SWL therapy alone, with risk ratios (95% confidence intervals) of being stone free of: PNL 2.19 (1.62-2.96); URS 1.23 (1.03-1.48); and SWL with an adjuvant therapy 1.30 (1.03-1.63). However, patients treated with the other treatment methods also had a higher risk of adverse events (AEs) compared with SWL, but there was no evidence of a convincing difference between the various techniques and AEs. CONCLUSION: In stones of <10 mm, SWL with an adjuvant therapy appears to have better stone clearance, lower risk of AEs, and need for further treatment. PNL was most effective treating larger stones, after considering both effectiveness and safety of treatment. These should be considered by both physicians and patients alike when considering the choice of treatment and in the revision of clinical practice guidelines.

Lessons learned from the CROES percutaneous nephrolithotomy global study.

PURPOSE: The purpose of the study was to give an overview of the data derived from the CROES PCNL Global Study published previously in 25 articles. METHODS: A comprehensive overview of the outcome of the CROES PCNL Global Study was made, analysed and compared with the current literature and guidelines. RESULTS: Percutaneous nephrolithotomy (PCNL) was predominately performed in prone position. Although the supine position claims to be favourable over the prone approach, the present study showed a longer operation time and lower stone-free rate (SFR). This might be explained by differences in definition in operation time and methods in the evaluation of residual stones. Ultrasound (US)-guided access proves beneficial in lowering puncture time and radiation exposure. Renal anomalies can safely be treated by PCNL and have similar outcomes to a normal situation. In patients with a solitary kidney, however, there is a lower SFR and more bleeding. Also, severe chronic kidney disease (CKD) patients have less favourable outcome. Morbidity and complications following PCNL are dominated by fever (10.5%) and bleeding (7.8%). A matched control analysis confirmed that antibiotic prophylaxis gives a threefold lower post-operative fever rate. In a multivariate analysis, it was elegantly demonstrated that bleeding was directly related to the size of the dilatation: the larger the bore, the higher the chance for bleeding. Elderly patients are at higher risk of complications and longer hospital stay. Overall, obese patients have similar outcome as the general population; however, super-obese (BMI > 40) patients have a higher chance of more severe complications. For the first time, this database illustrated a significant relationship between results and complications of PCNL, and caseload volume. The optimal case volume per centre appears to be 120 PCNL's/year. Finally, a nomogram has been developed that enables better patient counselling and decision-making. CONCLUSION: The CROES PCNL Global Study is the largest real-life study providing new insights into general and special conditions. Because of the vast number of patients included, rare conditions including renal anomalies, solitary kidneys and patient characteristics like severe CKD, super obesity and old age could be analysed. Besides this information, a nomogram was developed. And for the first time, the influence of caseload volume was established.

Percutaneous nephrolithotomy in England: practice and outcomes described in the Hospital Episode Statistics database.

OBJECTIVE: To investigate the postoperative outcomes of percutaneous nephrolithotomy (PCNL) in English National Health Service (NHS) hospitals. PATIENTS AND METHODS: We extracted records from the Hospital Episode Statistics (HES) database for all patients undergoing PCNL between March 2006 and January 2011 in English NHS hospitals. Outcome measures were haemorrhage, infection within the index admission, and rates of emergency readmission and in-hospital mortality within 30 days of surgery. RESULTS: A total of 5750 index PCNL procedures were performed in 165 hospitals. During the index admission, haemorrhage was recorded in 81 patients (1.4%), 192 patients (3.8%) had a urinary tract infection (UTI), 95 patients (1.7%) had fever, and 41 patients (0.7%) had sepsis. There were 595 emergency readmissions in 518 patients (9.0%). Reasons for readmission were varied: 70 (1.2%) with UTI, 15 (0.3%) sepsis, 73 (1.3%) haematuria, 25 (0.4%) haemorrhage, and 25 (0.4%) acute urinary retention. There were 13 (0.2%) in-hospital deaths within 30 days of surgery. CONCLUSIONS: Haemorrhage and infection represent relatively common and potentially severe complications of PCNL. Mortality is extremely rare after PCNL (about one in 400 procedures overall) but almost one in 10 patients have an unplanned hospital readmission within 30 days of surgery. Complications of PCNL may be under-reported in the HES database and need to be corroborated using other data sources.

Percutaneous nephrolithotomy increases the risk of diabetes: a 5-year follow-up study.

OBJECTIVE: To examine the risk of diabetes mellitus within a 5-year period among patients with nephrolithiasis undergoing percutaneous nephrolithotomy . METHODS: A total of 304 patients who underwent percutaneous nephrolithotomy were included in the study cohort. A total of 3040 patients with nephrolithiasis who did not undergo percutaneous nephrolithotomy were used as a comparison cohort. All participants included in the present study were individually tracked for a 5-year period in order to identify those who developed diabetes mellitus during this timeframe. RESULTS: The incidence rate of diabetes mellitus was 3.03 per 100 person-years in participants who underwent percutaneous nephrolithotomy and 1.65 per 100 person-years in participants who did not undergo percutaneous nephrolithotomy. After adjusting for the participants' monthly income, geographic location, urbanization level, hypertension, hyperlipidemia and alcohol abuse/alcohol dependence syndrome, the hazard ratio of receiving a first diagnosis of diabetes mellitus during the 5-year follow-up period was 1.96 (95% confidence interval 1.40-2.77) for participants who underwent percutaneous nephrolithotomy. Furthermore, compared with extracorporeal shock wave lithotripsy or endoscopic intervention, participants who underwent percutaneous nephrolithotomy had a significantly increased hazard of developing diabetes mellitus (adjusted hazard ratio 1.79 for a percutaneous nephrolithotomy vs extracorporeal shockwave lithotripsy, and adjusted hazard ratio 1.71 for a percutaneous nephrolithotomy vs an endoscopic intervention). CONCLUSIONS: The present results suggest an association between patients with nephrolithiasis who undergo a percutaneous nephrolithotomy and a subsequent diabetes mellitus diagnosis.

Emergent ureteric stent vs percutaneous nephrostomy for obstructive urolithiasis with sepsis: patterns of use and outcomes from a 15-year experience.

OBJECTIVES: To characterize the use of emergent JJ ureteric stent placement and percutaneous nephrostomy (PCN) for patients with obstructive urolithiasis with sepsis, and to determine whether outcomes differ between the two treatment methods. PATIENTS AND METHODS: A total of 130 patients with obstructive urolithiasis and systemic inflammatory response syndrome criteria were identified retrospectively from a single health system database from 1995 to 2011. Primary outcomes included stone-related and clinical variables which predicted the use of each treatment method. Secondary outcomes included the length of hospital stay, risk of intensive care unit (ICU) admission, and surgical approach used for definitive stone management. RESULTS: The overall rate of failed procedures was 2.3% (3/130), with one in-hospital death (0.8%). Patients treated with PCN had larger stones (10 vs 7 mm, P = 0.031), and were more acutely ill (acute physiology, age, chronic health evaluation [APACHE] II scores of 15 vs 11, P = 0.036) than those treated with JJ stent placement. Patients treated with PCN were more likely to require ICU admission (odds ratio: 3.23, 95% confidence interval [CI]: 1.24-8.41, P = 0.016), and demonstrated longer length of hospital stay (ß: 0.47, 95% CI: 0.20-0.74, P = 0.001), even when adjusting for age, APACHE II score, and Charlson Comorbidity Index score. After resolution of sepsis, patients treated with PCN were more likely to be treated definitively with a percutaneous approach, while patients treated with JJ stent placement were more likely to be treated ureteroscopically. CONCLUSIONS: Both JJ stent placement and PCN drainage appear effective. Patients with larger stones and who are more acutely ill are more likely to be treated with PCN. Additional randomized clinical trials of adequate power are warranted to define the optimum management of these often complex cases.

Percutaneous nephrolithotomy in children in different age groups: data from the Clinical Research Office of the Endourological Society (CROES) Percutaneous Nephrolithotomy Global Study.

OBJECTIVES: To present the overall results of paediatric percutaneous nephrolithotomy (PCNL) compared with adults. To present the indications, complications and outcomes of patients treated in the participating centres in the PCNL Global Study, as categorised in different age groups. PATIENTS AND METHODS: The Clinical Research Office of the Endourological Society (CROES) Study was conducted from November 2007 to December 2009, and included 96 centres and >5800 patients. All children aged ≤14 years in the PCNL Global Study database were the focus of the study. RESULTS: In all, 107 children aged ≤14 years were included in the analysis. The PCNL procedure was conducted in 13 patients (12.1%) in the supine position; tubeless PCNL was performed in 15 patients (14%); and balloon dilatation was preferred in 22 patients (20.5%). The overall mean operative duration was 97.02 min; blood transfusion rate, fever and stone-free rates were 9%, 14% and 70.1%, respectively. A comparison of the paediatric PCNL cases according to age groups showed no statistically significant differences between the subgroups for patient characteristics, co-morbidities, renal anomalies, or previous surgical history. In the evaluation of the operative details, the mean sheath size and nephrostomy tube size were larger in school-age children than the preschool children (P = 0.01 and 0.002, respectively). There was a difference in the preferred methods for confirming stone-free status, with ultrasonography preferred more in preschool children (P < 0.001). The PCNL procedure position, puncture site, dilatation method, postoperative tube application, and surgical outcomes were comparable in school- and preschool-age children. While operative details showed some differences between children and adults, the surgical outcomes were comparable. CONCLUSIONS: A considerable number (45.7%) of the paediatric patients had a previous history of stone intervention. Based on the findings of the present study, we can suggest that PCNL can be applied safely and effectively in children in different age groups. Outcomes appear comparable with those in adults for the success and complication rates, in the presence of substantial indications, appropriate equipment and adequate experience.

Longer operative time is associated with higher risk of severe complications after percutaneous nephrolithotomy: analysis of 1511 cases from a Japanese nationwide database.

OBJECTIVES: To evaluate risk factors of severe adverse events after percutaneous nephrolithotomy with an emphasis on operation time, and to develop a nomogram for predicting them. METHODS: This was an observational retrospective study including 1511 patients who underwent percutaneous nephrolithotomy in 332 hospitals identified from the Japanese Diagnosis Procedure Combination database between 2007 and 2010. Severe adverse events were defined as follows: (i) in-hospital mortality; (ii) postoperative medications including catecholamine, gamma-globulin products, protease inhibitors and medications for disseminated intravascular coagulation; and (iii) postoperative interventions including central vein catheterization, dialysis and mechanical cardiopulmonary support. Univariate and multivariate logistic regression analyses were carried out for the occurrence of severe adverse events, and a nomogram was generated from this model. RESULTS: Overall, 126 severe adverse events (8.34%) were identified. In the multivariate model, a linear trend between severe adverse events and operation time was observed (OR 4.72 for 120-179 min to 17.95 for ≥300 min compared with ≤119 min; each P < 0.05) after adjustment for sex, age, Charlson Comorbidity Index and type of admission. Female sex and emergency admission were also significant risk factors (OR 1.92 and 2.04, respectively), and hospital volume did not reach statistical significance. The nomogram based on these results was well fitted to predict a probability between 0.05 and 0.40 (concordance index 0.696). CONCLUSIONS: Longer operation time is a significant and independent risk factor for severe adverse events after percutaneous nephrolithotomy. Our nomogram can be an effective tool for predicting postoperative complications.

Surgeon fatigue: impact of case order on perioperative parameters and patient outcomes.

PURPOSE: We tested the hypothesis that surgeon fatigue results in worse outcomes for laparoscopic and robot-assisted laparoscopic prostatectomy, and percutaneous nephrolithotomy by comparing outcomes of sequentially scheduled procedures. MATERIALS AND METHODS: We identified days when 2 procedures of the same type were performed by the same surgeon, including 72 laparoscopic and 340 robot-assisted laparoscopic prostatectomies, and 110 percutaneous nephrolithotomies. Clinical data and outcomes were compared. RESULTS: For percutaneous nephrolithotomy multiple access (16% vs 9%, p = 0.2), transfusion (3.6% vs 5.4%, p = 0.5), complication (20% vs 18%, p = 0.5), residual fragment (53% vs 45%, p = 0.3), second look (38% vs 35% p = 0.4) and stone-free (86% vs 89% p = 0.3) rates did not differ for the first and second procedures. For laparoscopic prostatectomy nerve sparing (100% vs 97.1%, p = 0.5), operative complications (0% vs 0%, p = 0.7), drain requirement (36% vs 42%, p = 0.6) and lymphadenectomy (13.5% vs 25.7%, p = 0.16) rates were comparable. Positive margins (19.4% vs 36.1% p = 0.08), continence (66.7% vs 66.7%, p = 0.9), potency (58.3% vs 52.8%, p = 0.76) and prostate specific antigen recurrence (10.8% vs 20%, p = 0.45) did not significantly differ for the first and second procedures. For robot-assisted laparoscopic prostatectomy operative complications (3% vs 3.5%, p = 0.8), drain requirement (7.7% vs 9.8%, p = 0.5), positive margins (41.7% vs 39.3%, p = 0.37), continence (78.6% vs 84.4%, p = 0.12), potency (51% vs 50%, p = 0.15) and prostate specific antigen recurrence (9.5% vs 11.6%, p = 0.2) did not significantly differ. Nerve sparing was more common in the second case cohort (86.9% vs 75.7%, p = 0.03). CONCLUSIONS: Despite concern that surgeon fatigue may impact outcomes, our data suggests that performing several complex urological procedures consecutively is not associated with worse outcomes.

Trends in urological stone disease.

OBJECTIVE: To summarize the changes in prevalence and treatment of upper urinary tract stone disease in the UK over the last 10 years. METHODS: Data from the Hospital Episode Statistics (HES) website (http://www.hesonline.nhs.uk) were extracted, summarized and presented. RESULTS: The number of upper urinary tract stone hospital episodes increased by 63% to 83,050 in the 10-year period. The use of shock wave lithotripsy (SWL) for treating all upper tract stones increased from 14,491 cases in 2000-2001 to 22,402 cases in 2010 (a 55% increase) with a 69% increase in lithotripsy for renal stones. There was a 127% increase in the number of ureteroscopic stone treatments from 6,283 to 14,242 cases over the 10-year period with a 49% increase from 2007/2008 to 2009/2010. There was a decline in open surgery for upper tract stones from 278 cases in 2000/2001 to 47 cases in 2009/2010 (an 83% reduction). Treatment for stone disease has increased substantially in comparison with other urological activity. In 2009/2010, SWL was performed almost as frequently as transurethral resection of the prostate or transurethral resection of bladder tumour, ureteroscopy for stones was performed more frequently than nephrectomy, radical prostatectomy and cystectomy combined, and percutaneous nephrolithotomy was performed more frequently than cystectomy. CONCLUSIONS: The present study highlights the increase in prevalence and treatment of stone disease in the UK over the last 10 years. If this trend continues it has important implications for workforce planning, training, service delivery and research in the field of urolithiasis.

Evidence-based management of upper tract urolithiasis in the spinal cord-injured patient.

OBJECTIVE: The objective is to review the published literature on the aetiology and evidence-based management of stone disease in the spinal cord-injured patient. METHODS: A PubMed and Medline search was performed using the terms 'spinal cord injury', 'paraplegia', 'stone', 'nephrolithiasis', 'urolithiasis', 'calculus', 'spinal cord injury' or 'paraplegia' with 'SWL', 'ureteroscopy', 'chemolysis' and 'PCNL.' The Cochrane database, the National Institute for Clinical Excellence guidelines and the Scottish Intercollegiate guidelines were searched using the terms 'spinal cord injury' and 'urolithiasis' and 'nephrolithiasis'. RESULTS: A total of 32 papers were identified, mainly case series or case-cohort studies with few contemporary papers. The risk of developing a renal stone after spinal cord injury (SCI) is between 7 and 20% over a period of 8-10 years. Stone formation may be related to early demineralisation of bone or chronic infection. Biochemical abnormalities are not significantly different between stone-forming and non-stone forming patients, though these patients differ from healthy controls. Presentation may be atypical, but is most commonly recurrent urinary tract infection. Treatment may be complicated by lower limb contractures limiting retrograde access. Several case series report success with shock wave lithotripsy varying from 50 to 70%, though comparisons are limited by heterogeneous indications and reporting. Percutaneous nephrolithotomy remains the gold standard for stones measuring 2 cm and above. Stone-free rates of 90% have been reported, though surgery was often complex with higher complication rates. CONCLUSION: Management of upper urinary tract stones in patients with SCI is complex regarding surgical technique, post-operative care and recurrence rates. Further contemporary case series must use standardised reporting tools to allow valid comparisons.

Tubeless percutaneous nephrolithotomy: first 200 cases in Israel.

BACKGROUND: Tubeless percutaneous nephrolithotomy is defined as PCNL without postoperative nephrostomy tubes. It is reported to reduce postoperative pain, hospital stay and recovery time. To date the procedure has been reserved for selected patients. OBJECTIVES: To assess our initial experience in extending the implementation of tubeless PCNL without preoperative patient selection. METHODS: All consecutive PCNLs performed during 2004-2008 were evaluated. Tubeless PCNL was performed when residual stones, bleeding and extravasation were excluded intraoperatively. Staghorn stones, stone burden, supracostal and multiple accesses, anatomic anomalies, solitary kidneys and operative time were not considered contraindications. We analyzed the clinical data and the choice of tubeless PCNL over time. RESULTS: Of 281 PCNLs performed during the study period 200 (71%) were tubeless. The patients' average age was 53 years (range 28-82 years), the stone burden was 924 mm2 (400-3150 mm2), operative time was 99 minutes (45-210 min), complication rate was 14% and immediate stone-free rate 91%. There were 81 conversions to standard PCNL (29%) due to expected second-look (n = 47, 58%), impression of bleeding (n = 21,26%), suspected hydrothorax (n = 7, 9%) and extravasation (n = 6, 7%). The transfusion rate was 1%. The median hospital stay was 1 day (1-15 days) and recovery time 7 days (5-20 days). The rate of implementing the tubeless procedure increased steadily along time from 46% to 83% (P = 0.0001). CONCLUSIONS: Tubeless PCNL can be safely and effectively performed based on intraoperative decisions, without preoperative contraindications. They are easily accommodated by experienced endourologists and provide real advantages.