Standard v mini percutaneous nephrolithotomy in the supine modified lithotomy position: a randomized pilot study on 10-25 mm stones.

BACKGROUND: Percutaneous nephrolithotomy (PCNL) is the recommended treatment for stones >2 cm in size. The majority of PCNL are still conducted with larger telescopes using tracts up to 30F in size. We have conducted a randomized pilot study comparing mini PCNL with our standard 22F PCNL for renal stones between 10 and 25 mm in diameter. METHODS: Patients were randomized to either PCNL (24F Amplatz sheath/22F nephrosocope) or mini PCNL (18F Amplatz sheath/11F nephroscope). All operations were performed in the modified supine position. Patients were reviewed with imaging to assess stone clearance and complications. RESULTS: Eighteen well matched patients were randomized. All procedures were completed as planned and all were tubeless with no complications. There were no differences in operative time, analgesia requirements or length of stay. Seven of nine (77.75%) standard PCNL were completely stone free at CT review with a 2 mm and a 5 mm fragments in the other patients. Four (44.4%) of the mini PCNL group were stone free, with stone fragments 4-10 mm remaining in the others. 40 patients/arm would be required for an adequately powered study. CONCLUSION: There was no advantage in using mini PCNL compared to our standard 24F PCNL in this pilot study. There may be benefits in using mini PCNL compared to the more widely used 30F PCNL and it may be a more cost-effective alternative to laser pyeloscopic stone procedures.

The association between novel negative pressure ureteroscopic lithotripsy combined with flexible ureteroscopy versus percutaneous nephrolithotomy on stone-free rates: implications for clinical practice and policy.

The correlation between novel negative pressure ureteroscopic lithotripsy (NP-URL) combined with flexible ureteroscopy (FU) and percutaneous nephrolithotomy (PCNL) on stone-free rates (SFR) remains unclear. There is a lack of evidence from Chinese populations regarding the relationship between SFR and NP-URL combined with FU (NP-URL-FU) versus PCNL. We aimed to assess the association between NP-URL-FU and PCNL on SFR. We conducted a cohort study involving 166 participants with 2-4 cm kidney stones. Data on SFR (7 days and 2 months) were collected from all participants. Logistic regression analysis was used to substantiate the research objectives. NP-URL-FU versus PCNL showed an 86% decrease in the 7-day SFR (OR = 0.14, 95% CI 0.07-0.29). The results remained stable even after adjusting for potential confounders. However, no statistically significant association was found between the surgical method and the 2-month SFR. Further exploratory subgroup analyses showed no significant interactions, with all P values > 0.05. Among patients with 2-4 cm kidney stones, NP-URL-FU was associated with a lower risk of incident 7-day SFR than PCNL. However, no statistically significant difference was found in the long-term stone removal rate. Therefore, NP-URL-FU may be a viable alternative surgical option for patients seeking minimally invasive procedures.

Is double-J stent mandatory in complete supine percutaneous nephrolithotomy for adult patients with staghorn renal stones?

BACKGROUND: It is controversial whether double-J (DJ) stent insertion is necessary in tubeless percutaneous nephrolithotomy (PCNL) for patients with staghorn stones. We compared the outcomes of using ureteral catheters and double-J stents in tubeless complete supine PCNL (csPCNL) of staghorn stones. METHODS: In this analytical cross-sectional study, from May 2008 to August 2022, 123 patients who underwent tubeless csPCNL were assessed. Patients were divided into two groups by either tubeless csPCNL with DJ stent (Group I; n = 23) or totally tubeless just with perioperative ureteral stent (Group II; n = 100). Demographic characteristics, stone-related factors, perioperative and postoperative parameters were compared in groups. RESULTS: Baseline characteristics were comparable in groups. The operative time in group I was significantly longer than group II (68.26 vs. 55.25 min, P = 0.05). However, the duration of hospitalization in Group I was shorter than the other group (1.81 vs. 2.37 days, P = 0.03). Stone free rate was notably higher in Group I (90.5% vs. 79.8.0%) with no statistically significant difference. No significant differences were found in major complications. Patients in Group II had a significantly shorter time to return to normal life (6.48 vs. 7.91 day; P = 0.043). Multivariable linear regression showed the preoperative creatinine level and stone size can affect the operative time (P = 0.02). In addition, stone number and underlying disease can affect the length of hospital stay (P = 0.007 & 0.030, respectively). CONCLUSION: Although not inserting a double J stent after csPCNL has acceptable results, because of higher residual rate in staghorn stone which cause more incidence of renal colic, longer time of hospital stay and return to normal life, inserting DJ stent is recommended.

Supine versus prone pediatric percutaneous nephrolithotomy: A systematic review and meta-analysis.

Percutaneous nephrolithotomy (PCNL) is the treatment of choice for pediatric nephrolithiasis more than 20 mm. Prone position was the preferred position for decades. Recently, supine position has gained more interest. This meta-analysis aims to evaluate the safety and efficacy of PCNL in supine versus prone position in pediatric population. A systematic search of PubMed, Scopus, Web of Science, and Cochrane Library was performed till 28 February 2024. The study included comparative studies comparing both positions in children that were written in English. A total of three randomized studies and three retrospective studies were included with a total number of 290 patients. Cochrane risk-of-bias tool for randomized trials was used for quality assessment, while Newcastle-Ottawa scale was used for non-randomized controlled trials. The meta-analysis was conducted using Review Manager software. Numerical data were analyzed using standardized mean difference (SMD), while the risk ratio was used for analysis of categorical data. Fixed or random effects models were used according to heterogeneity. There were statistically insignificant differences between both groups for stone-free rate (RR 1.08, 95% CI [0.98-1.18], p = 0.11) and overall complications (RR 0.93, 95% CI [0.59-1.47], p = 0.76). Operation time was significantly shorter in supine group (SMD -0.99, 95% CI [-1.67 to -0.30], p = 0.005). Therefore, comparable efficacy and safety outcomes were proved between both supine and prone positions for PCNL in pediatrics.

Outcomes and complications of percutaneous nephrolithotomy as primary versus secondary procedure for kidney stones: a prospective cohort study.

Introduction: Currently, percutaneous nephrolithotomy (PCNL) is the gold standard of treatment for large renal stones. The high prevalence of urolithiasis is associated with a high recurrence rate increasing the risk of re-intervention. This study aimed to compare the effectiveness and complications of PCNL among patients with previous therapeutic interventions for renal stones. Methods: Between August 2018 and September 2023, 245 patients were prospectively enrolled in this study and who underwent PCNL for renal stones at our institution. We compared patients who had no previous renal surgery (group 1: n=171) with those who had a history of open renal surgery (group 2: n=45) or previous PCNL on the ipsilateral kidney (group 3: n=31). All patients underwent surgery in the Galdakao-modified Valdivia position. Data on stone characteristics and perioperative and postoperative parameters were collected. Technical features, success rates and morbidity were analyzed and compared between the groups. Results: The fluoroscopy time was significantly longer in the group of patients with previous open surgery than in groups 1 and 3 (161.47±52.44, 223.05±33.29, 172.27±30.51 sec, P<0.001). Similarly, the operative time was longer in group 2 (138.20±38.86 min, P<0.001). The immediate stone-free rates in groups 1, 2, and 3 were 74.8%, 72.1%, and 77.4%, respectively (P=0.945). At 1-month, these rates increased to 98.8%, 96.2% and 96.8%, respectively (P=0.857). No difference was detected between the groups in terms of complication rate. The average Hb variation was 1.08±0.82, 1.34±1.01 and 0.94±0.69 g/dl for groups 1, 2 and 3, respectively(P=0.082). Hospital stay was longer in group 2 than in groups 1 and 3 (2.17±1.03, 2.53±1.22, 1.88±1.00 days, P=0.07), respectively. Conclusion: PCNL in patients with a history of renal surgery was associated with longer fluoroscopy and operative time. However, the success and morbidity rates as a secondary procedure were similar to those of PCNL in patients with no previous intervention.

Calyceal Rupture Secondary to Nephrolithiasis: A Case Report Emphasizing Early Diagnosis and Management.

Calyceal rupture, defined as the extravasation of urine from the renal calyces into the perinephric or paranephric spaces, typically results from increased intrapelvic pressure due to urinary tract obstruction. This condition can lead to the formation of a perinephric urinoma and severe complications, such as infection, abscess formation, and impaired renal function. Timely diagnosis and management are crucial to prevent these adverse outcomes. Calyceal rupture often results from urolithiasis, with other causes including strictures, tumors, and congenital abnormalities. The rupture occurs when intrapelvic pressure exceeds the tensile strength of the calyceal walls, leading to urine leakage and potential inflammation or sepsis. Calyceal ruptures are quite rare, with their exact incidence not well-documented due to the infrequency of the condition and potential underreporting. Although relatively uncommon, the condition is more prevalent in individuals with recurrent nephrolithiasis and other predisposing factors. Timely recognition and intervention, guided by imaging studies such as non-contrast CT scans, are essential. Conservative management with medical therapy is effective in many cases, but surgical intervention may be necessary for larger stones or complications. This report presents the case of a 36-year-old female with calyceal rupture secondary to nephrolithiasis, presenting with severe flank pain. Upon initial presentation, the patient underwent a thorough workup, including imaging studies, appropriate medical management, and continuous monitoring. She was stabilized, her pain was effectively managed, and she was discharged with a scheduled outpatient follow-up. This case highlights the importance of early diagnosis, comprehensive management, and vigilant monitoring in preventing complications and promoting favorable outcomes.

Risk factors and prediction model for postoperative complications in patients with struvite stones after percutaneous nephrolithotomy and flexible ureteroscopy.

OBJECTIVE: To analyze the risk factors for complications in patients with struvite stones following percutaneous nephrolithotomy (PCNL) or flexible ureteroscopy (fURS), and to establish a nomogram for postoperative complications in patients following PCNL. METHODS: A retrospective analysis was conducted on patients with struvite stones after PCNL and fURS at the Department of Urology, Peking University People's Hospital, from January 2012 to March 2022. The common pathogens and antimicrobial susceptibilities in preoperative midstream urine culture were analyzed. Logistic regression analyses were used to evaluate the risk factors. Receiver-operating characteristic (ROC) curve, calibration plots, and decision curve analysis (DCA) were used to assess the discrimination, accuracy, and practicability of the nomogram. RESULTS: 332 patients with struvite stones received one-stage PCNL or fURS, including 243 cases of PCNL and 89 cases of fURS. 72 patients (21.69%) developed postoperative complications. The most common pathogens in preoperative urine cultures were Escherichia coli, Proteus mirabilis, and Enterococcus faecalis. Multivariate logistic regression analysis showed that preoperative hemoglobin (OR = 0.981, P = 0.042), staghorn stone (OR = 4.226, P = 0.037), and positive preoperative midstream urine culture (OR = 2.000, P = 0.043) were independent risk factors for postoperative complications in patients following PCNL. The nomogram showed good performance in discrimination, accuracy, and applicability. CONCLUSION: Preoperative hemoglobin, staghorn stone, and positive preoperative midstream urine culture were independent risk factors for postoperative complications in patients with struvite stones following PCNL. A nomogram was developed to predict the probability of postoperative complications.

The Association Between Preoperative Neutrophil-Lymphocyte Ratio and Febrile Urinary Tract Infection in Patients Treated by Percutaneous Nephrolithotomy.

Objective: This study aimed to assess the association between preoperative neutrophil-lymphocyte ratio (NLR) and febrile urinary tract infection (fUTI) in patients who underwent percutaneous nephrolithotomy (PCNL). Patients and Methods: The clinical data of patients who underwent PCNL at our hospital between March 2020 and May 2023 were retrospectively analyzed. According to whether fUTI occurs after operation, collected data were divided to the patients into fUTI and non-fUTI. Univariate analysis, relative operating characteristic (ROC) curves and multivariate logistic regression analysis were performed on the data. Results: A total of 405 patients were enrolled in the study. The procedure was successfully performed in all patients, and the incidence of fUTI was 8.4% (34/405). Eight patients eventually developed sepsis, and the incidence of sepsis in fUTI patients was 23.5%. The result shows a significant correlation between NLR and fUTI (95% confidence interval [CI],1.21-1.83, Odds ratio [OR]=1.49, p<0.001). The predictive ability of NLR on the occurrence of fUTI was assessed by plotting relative operating characteristic (ROC) curves. The area under the curve (AUC) in the ROC curve for NLR was 0.718 according to the Youden index, and the best cut-off value of NLR was 2.71. Furthermore, logistic multiple regression model adjustment was carried out to further confirm the robustness of the relationship between NLR and fUTI. The results indicated robustness regardless of whether NLR was a continuous variable or a categorical variable. Conclusion: NLR can be used as a simple and effective preoperative indicator for the prediction of fUTI in patients undergoing PCNL.

Comparison of the Efficacy Between Ultrasound-Guided Paravertebral Block and Erector Spinae Block for Postoperative Analgesia in Percutaneous Nephrolithotomy Using Levobupivacaine: A Prospective and Randomized Study.

Introduction Various techniques have been developed in the current era of regional anesthesia practice. With the advent of ultrasound, the visualization of needle and pleura in real time enables a better outcome with negligible adverse events. This study was designed to compare the efficacy between ultrasound-guided erector spinae plane block (ESPB) and paravertebral block (PVB) in percutaneous nephrolithotomy (PCNL) for the duration of postoperative analgesia with levobupivacaine, a local anesthetic with higher lipid solubility, making it more potent and resulting in a longer duration of action. Methods This prospective randomized single-blinded study enrolled 50 patients of ASA grades I and II, aged between 20 and 60 years, who were scheduled for PCNL under general anesthesia. Patients were divided into two groups of 25 each: group ESPB and group PVB, and 25 mL of 0.25% levobupivacaine was administered to both groups. They were primarily evaluated for the duration of postoperative analgesia. Total rescue analgesic requirements, hemodynamic parameters, and any adverse effects were also assessed. Results Both ESPB and PVB provided a significant duration of analgesia postoperatively. Demographic characteristics in both groups were comparable. The duration of postoperative analgesia in group ESPB was 746 ± 58.6 minutes when compared to group PVB, which is 768 ± 68.6 minutes (p = 0.08). Intravenous (IV) paracetamol was used as a rescue analgesic. The doses used were also comparable in both groups, with the visual analog score (VAS) being high after around 12 hours of surgery. The total rescue analgesic requirement was similar in both groups (group ESPB, 2.0 ± 1.6; group PVB, 2.2 ± 1.4; p = 0.51). There were no significant hemodynamic or other adverse effects in either group. Conclusion We conclude that both ESPB and PVB using isobaric levobupivacaine 0.25% as a local anesthetic are equally efficacious in providing effective postoperative analgesia in patients undergoing PCNL under general anesthesia.

Managing a challenging case of bilaterally fractured DJ stents following extracorporeal shock waves lithotripsy for chronic encrustations: A case report.

Double-j stents are commonly used in many urological procedures to facilitate the drainage of renal systems postoperatively. Their usage has revolutionized the world of urological interventions but if left forgotten present serious complications. We report a case of an old man who was diagnosed with bilaterally fragmented DJ stents in situ in our urology department following his sessions of extracorporeal shock wave lithotripsy for chronic encrustations. These stents were placed after complete breakdown of bilateral ureteral stones through ureterorenoscopy and laser lithotripsy.

Exploring the competency of the comprehensive complication index over the clavien-dindo classification in standard percutaneous nephrolithotomy: a call for better complication reporting.

PURPOSE: The Comprehensive Complication Index (CCI) was introduced in 2013 to overcome the limitations of the Clavien-Dindo Classification (CDC) in grading postoperative complications. The objective of this study to assess the predictive value of the CDC and the CCI for postoperative course in patients undergoing standard adult percutaneous nephrolithotomy (PCNL). METHODS: A retrospective analysis of 320 renal units that underwent standard PCNL between July 2021 - April 2023 was conducted. The CDC and CCI systems assessed complications occurring within the first 30 days after surgery. A second CCI score was calculated only on the highest CDC grade, and this score was referred to as the noncumulative CCI. A comparative analysis was conducted to determine the predictive efficacy of both evaluation methods regarding the postoperative course. RESULTS: The postoperative complication rate was 23.1% (74/320). Eight patients (2.5%) experienced multiple complications, resulting in a higher total CCI score than the noncumulative CCI (p = 0.010). Correlation analysis revealed that the CCI correlated with the length of hospital stay (LOS) more precisely than the noncumulative CCI (CCI: r = 0.335; p = 0.004 vs. noncumulative CCI: r = 0.325; p = 0.005). Compared with patients with a single complication, those with multiple complications had similar demographics, preoperative stone characteristics, and intraoperative features. CONCLUSION: Cumulative CCI proves to be a more effective predictor of LOS and complication burden in standard PCNL than CDC. Hence, using CCI to evaluate complications after PCNL may be a more appropriate approach.

Are very thin patients at a higher risk of complications when submitted to percutane-ous nephrolithotomy?

PURPOSE: To assess the impact of thinness on the outcome of the percutaneous nephrolithotomy (PCNL). MATERIALS AND METHODS: A matched case-control study was performed using a prospectively collected database of all patients who underwent PCNL between June 2011 and October 2021. The patients were stratified into two groups according to their phenotypic characteristics, arbitrarily defined according to their body mass index (BMI): <0kg/m2 (Group 1, very thin patients, G<20) and ≥25 kg/m2 (Group 2, non-thin patients, G≥25). Patients were randomly matched based on Guy's Stone Score (GSS) according to case complexity at a ratio of 1:3. RESULTS: A total of 204 patients were enrolled in this study: 51 patients (G<20) and 153 controls (G≥25). Complications occurred in 15.2% of the patients, with 5.4% of these complications classified as major complications (Clavien grade ≥ 3). According to complications there were no significant differences between the groups. The overall complication rates were 17.6% in the G<20 and 14.4% in the G≥25 (p = 0.653). The major complication rates were 3.9% in the G<20 and 5.8% in the G≥25 (p=0.429). No differences in transfusion or urinary fistula rates were found. CONCLUSIONS: In this study, very thin patients were not at a higher risk of complications when submitted to PCNL than in those with a BMI of ≥25 kg/m2. Apparently, this technique can be used in these patients, just as it is used in any other type of patient, independently of their BMI.

Supine percutaneous nephrolithotomy in horseshoe kidney.

Introduction: Historically, percutaneous nephrolithotomy (PCNL) in horseshoe kidney (HSK) patients has been performed in the prone position. Nevertheless, thanks to the spread of the supine PCNL technique for patients with urinary stones and normal renal anatomy, some retrospective studies have already reported on supine PCNL and HSK, showing the effectiveness and safety of the procedure. Herein we report our experience with supine PCNL in a subset of patients with urolithiasis. Material and methods: Prospective data were collected for all HSK patients who underwent supine PCNL at our institution from June 2016 to June 2023. Stone volume was reported as the volume of a single stone or the sum of the volumes of multiple stones on computed tomography (CT) images. Patients were reported to be stone-free if there were no stones on postoperative non-contrast CT (NCCT) exam. Peri-/postoperative complications were reported according to the Clavien-Dindo classification system. The primary endpoint of the study was stone-free rate (SFR) and the secondary endpoints were Clavien-Dindo complications Grade I or higher. Results: A total of 35 patients met the inclusion criteria and were enrolled in the study. Forty-eight procedures were analyzed. SFR was 72.9% at 1-month follow-up. In 11 out of 48 procedures (22.9%) Clavien-Dindo Grade I-II complications were recorded. In one case Clavien-Dindo Grade IIIa complication was observed. Conclusions: In this prospective study of 35 HSK patients who underwent 48 procedures, supine PCNL was safe and effective, with minimal morbidity.

Predicting and Avoiding Complications in Percutaneous Nephrolithotomy in the Era of Personalized Medicine: A Scoping Review.

BACKGROUND: Percutaneous nephrolithotomy (PCNL) is associated with a wide range of complications. This review aims to explore how recent technological advancements and personalized medicine can help prevent or predict these complications. METHODS: A scoping review was conducted according to the PRISMA-SCR guidelines and registered on the Open Science Framework in April 2024. A literature search was performed on PUBMED, Web of Science, and Scopus databases. This review focused on predictive AI models, 3D surgical models, intrasurgical image guidance, and biomarkers. Articles meeting the following criteria were included: publication between 2019 and 2024, written in English, involving human participants, and discussing technological advancements or personalized medicine in the context of complications in PCNL. RESULTS: Of the 11,098 articles searched, 35 new studies were included. We identified a few articles on predictive AI models. Several studies demonstrated that 3D presurgical models and virtual models could enhance surgical planning and reduce complications. New intrasurgical image and guidance systems showed the potential in reducing bleeding and radiation exposure. Finally, several biomarkers were identified as predictors of sepsis and other complications. CONCLUSION: This scoping review highlights the potential of emerging technologies in reducing and predicting PCNL complications. However, larger prospective studies are required for validation.

A meta analysis of the lateral decubitus position and prone position percutaneous nephrolithotomy.

Objective To analyzed the safety and efficacy of percutaneous nephrolithotomy (PCNL) in lateral decubitus position and prone position for upper ureteral calculi. Methods Databases including PubMed, Springer, ScienceDirect, Wiley Online Library, CNKI, CSPD and VIP were searched for clinical controlled studies involved with lateral decubitus position and prone position PCNL from their establishment to November 2023.Studies were enrolled according to inclusion and exclusion criteria. the dates were compared by Review Manager 5.4 software. Results seven studies were eligible, including 807 cases. The Meta-analysis showed that, blood loss and perioperative complication rate of lateral decubitus position PCNL group were significantly different from those of the prone position PCNL group (P < 0.05). There was no significant difference between the two groups regarding hospital time, operative time, channel establishment time and stone-free rate (P>0.05).Conclusions The lateral decubitus position can reduce blood loss and perioperative complication rate. The lateral decubitus position PCNL is safe and effective for upper ureteral calculi which was deserved clinical popularizing use.

Effects of anterior quadratus lumborum block versus erector spinae plane block on postoperative acute pain in percutaneous nephrolithotomy: a prospective, observational study.

BACKGROUND: The study aimed to compare the pain-relieving effectiveness of anterior quadratus lumborum block (QLB3) and erector spinae plane block (ESPB), both of which have been documented to provide relief during abdominal surgery. METHODS: This prospective observational study, conducted between February and July 2023, included 96 patients who had undergone percutaneous nephrolithotomy (PCNL). Patients were divided into three groups: QLB3, ESPB, and control (no block) and received the corresponding nerve block in the preanesthetic room for regional block. Cumulative morphine consumption during the initial 24 h after PCNL, numerical rating scale resting/movement scores, intraoperative remifentanil usage, rescue analgesic requirements, time when the first analgesic was requested, and postoperative nausea and vomiting scores were documented and compared between the groups. RESULTS: Total median morphine consumption in the first 24 h postoperatively was similar in the QLB3 and ESPB groups but higher in the control group (QLB3, 7 mg [(Q1-Q3) 7-8.5]; ESPB, 8 mg [6.5-9]; control, 12.5 [10-17]; P < 0.001). Similarly, median intraoperative remifentanil consumption did not differ between the block groups but was higher in the control group (QLB3, 1082 µg [IQR 805.5-1292.7]; ESPB, 1278 µg [940.2-1297.5]; control, 1561 µg [1315-2068]; P < 0.001). The number of patients receiving rescue analgesic medication was similar in the block groups but higher in the control group (QLB3, n = 9 [30%]; ESPB, n = 14 [46.7%]; control, n = 21 [70%]; P = 0.008). CONCLUSIONS: QLB3 and ESPB were adequate and comparable in providing postoperative analgesia as part of multimodal analgesia after PCNL. TRIAL REGISTRATION: The study was registered on ClinicalTrials.gov (Identifier: NCT05822492).

Analyzing learning curve for supine percutaneous nephrolithotomy in urology resident training programme: comparative analysis.

INTRODUCTION: This article attempts to provide a comprehensive review of the learning objectives and importance of the supine percutaneous nephrolithotomy (PCNL) technique. MATERIAL METHOD: We retrospectively reviewed the cases of Supine PCNL between January 2018 and January 2024. We divided the groups into 3: residents between 2 and 3 years (Group 1), residents between 4 and 5 years (Group 2), and endourologist (Group 3). The 2-3-year resident started to perform PCNL for the first time, while the 4-5-year resident started to perform Supine PCNL for the first time while previously performing prone PCNL. RESULTS: Access, fluoroscopy, and operation time were higher in Group 1, shorter in Group 2, and shortest in Group 3 (p < 0.001). Postoperative length of stay and the need for additional treatment were found to be shorter (p < 0.001), and the stone-free rate (SFR) increased (p < 0.001) from Group 1 to Group 3. The highest complication rates were observed in Group 1 (p = 0.002). SFR rate increased as the number of cases increased in Group 1 patients. Success was stable after 46-60 cases in terms of SFR. In Group 2, the SFR rate was stable after 31-45. CASES: The most complications were observed in Group 1 and the least in Group 3. CONCLUSION: In 2-3-year residents, access time and fluoroscopy time decrease with experience. In 4-5-year residents, due to their expertise in prone PCNL, the operation time and fluoroscopy time decrease with the number of cases performed. SFR is higher after 46-60 cases for 2-3-year residents and 31-45 cases for 4-5-year residents.

Application of warning biopsies in percutaneous nephrolithotomy.

Background: At present, few articles on percutaneous nephrolithotomy (PCNL) for renal calculi and renal pelvic tumors detected by intraoperative biopsy exist, which has provided limited guidance for clinical practice. In this article, we aimed to further study the relationship between renal calculi and renal pelvic tumors. Methods: We retrospectively analyzed the medical records of patients with abnormal mucosal biopsy results who underwent PCNL for kidney stones in the Urology Department of Peking University People's Hospital from January 2011 to November 2021. Results: In total, 2,801 patients underwent PCNL for kidney stones, of whom 69 underwent intraoperative mucosal biopsy. Biopsy results indicated that 8 cases were malignant (11.60%), and 61 cases were benign (88.40%). All malignant cases were renal pelvic carcinoma. Seven were urothelial carcinoma, and one of these was urothelial carcinoma with squamous differentiation. Only one was squamous cell carcinoma. The preoperative information of patients with a malignant mucosa biopsy was analyzed. To provide clinical guidance, an early warning biopsy system was established based on the abnormal mucosa found during the operation. We found that PCNL should be considered if the following risk factors are associated with stones: advanced age, long history of kidney stones, severe hydronephrosis, urinary tract infection, multiple or staghorn stones. Conclusions: Early warning information should be established for patients with kidney stones based on preoperative clinical characteristics and intraoperative mucous membrane observations. An early warning biopsy should be performed for patients with possible tumors to detect tumors in a timely manner and provide early treatment to improve patient prognosis.

Intravenous misplacement of the nephrostomy catheter following percutaneous nephrolithotomy: A case report and review of 26 cases in the literature.

Intravenous misplacement of the nephrostomy catheter following percutaneous nephrolithotomy (PCNL) is severe and extremely rare, and little information is available about this complication. Because the patient's prognosis may be poor, sufficient attention should be paid to early identification and treatment of this complication. We report a case with intravenous misplacement of nephrostomy catheter and severe bleeding from the catheter after PCNL was transferred to our hospital. The patient was successfully managed using a two-step intervention. First, the patient underwent embolization of the pseudoaneurysms in renal parenchyma, then underwent catheter withdrawal under digital subtraction angiography (DSA) and control bleeding by pushing the absorbable hemostatic material (Surgicel) into the tunneled renal drainage. There were no severe complications. Withdrawal could be performed by open surgery or under the supervision of imaging modalities. Some reports showed that minimally invasive management was safer and less invasive than open surgery.

Supine Percutaneous Nephrolithotomy: Preliminary experience in a single hospital.

Background and Objective: Percutaneous Nephrolithotomy (PCNL) is recommended for large Kidney Stones. It is mostly done in prone position. However, PCNL in Supine position is another safe option. Only few centers in country are doing it and so it is challenging task to adopt supine PCNL approach in an institution initially. In this study our purpose was to assess initial experience of Supine PCNL in our center. Methods: It is a preliminary retrospective study of our first fifty-one supine PCNL procedures, performed by a single Surgeon, over Twelve months period, from April 2021 to April 2022. We managed a retrospective review of patients' records. Analysis was completed by utilizing SPSS version 20. Implementation of Mean along with standard deviation values was utilized for continuous variables. While frequency/percentages represented categorical factors. Results: Patients mean age was 39 years, comprising of 62.74% male and 37.25% female patients. Thirty patients had their stones treated on the left side. Mean Stone burden was 3.2 cm. Most of the stones were GUYs score one and two (complexity wise). The mean procedure time 147minutes. Mean hospital stay of 2.17 days was observed in this study. Forty patients were stone free. Only seven patients (14%) had level I-II complications (Clavien-Dindo classification). Conclusion: Supine PCNL can be adopted safely in an institute if careful selection of patients is done before surgery. In our center it had acceptable success rates and few complications.