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).

Endoscopic Combined Intrarenal Surgery: best practices and future perspectives.

INTRODUCTION: Endoscopic Combined Intrarenal Surgery (ECIRS) has emerged as a promising technique for the management of large and complex kidney stones, potentially offering advantages over traditional Percutaneous Nephrolithotomy (PCNL). This study aims to evaluate best practices, outcomes, and future perspectives associated with ECIRS. MATERIALS AND METHODS: A comprehensive PubMed search was conducted from 2008 to 2024, using MESH terms and the following key words: "ECIRS" and "Endoscopic Combined Intrarenal Surgery" The search yielded 157 articles, including retrospective cohort studies, two randomized controlled trials (RCTs), and four meta-analyses comparing ECIRS with PCNL. Most important findings were summarized regarding indications, patient positioning, kidney access, tract size, surgical outcomes, and complications. RESULTS: ECIRS demonstrated higher stone-free rate, lower complication rate, and a reduced need for multiple procedures compared to traditional PCNL. Additionally, ECIRS has the potential to integrate new technologies to further enhance outcomes. CONCLUSION: ECIRS demonstrates significant advantages in the management of large kidney stones. Future research should focus on well-designed RCTs to provide robust evidence of its efficacy, safety, and cost-effectiveness, potentially establishing ECIRS as the first option treatment for complex kidney stones.

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.

Comparison of percutaneous nephrolithotripsy combined with retrograde intrarenal surgery and multi-tract percutaneous nephrolithotripsy for octopus stone: A propensity score-matching study.

To compared the effectiveness and safety of single standard mini percutaneous nephrolithotripsy (SM-PCNL) combined with retrograde intrarenal surgery (RIRS) and multiple standard mini percutaneous nephrolithotomy (MSM-PCNL) in the treatment of octopus stone of 2 to 4 cm. The clinical data of SM-PCNL combined with RIRS and MSM-PCNL for octopus stone with a 2 to 4 cm diameter from October 2019 to December 2022 were analyzed retrospectively, and propensity score matching was used to screen patients. The matched patients were paired, and the operation time, complications, postoperative pain, tubeless rate, stone-free rate (SFR), and postoperative hospital stay were further compared between the 2 groups. 88 patients underwent SM-PCNL combined with RIRS (combined group), and 143 patients underwent MSM-PCNL (multiple channel group). After matching analysis, there were 49 patients in each group, and there was no significant difference in the general preoperative data between the 2 groups. The perioperative complications and stone-free rate were no statistical difference. In postoperative pain (4.00 ±â€…0.74 vs 5.00 ±â€…0.74, P = .00), tubeless rate (44.90% vs 20.41%, P = .01), hemoglobin drop (9.38 ±â€…7.48 vs 14.22 ±â€…7.69, P = .01), postoperative hospital stay (3.37 ±â€…1.09 vs 5.08 ±â€…1.29, P = .00), the combined group was significantly better than the multiple channel group. Regarding operation time, the combined group was more than the multiple channel group (103.27 ±â€…27.61 vs 78.39 ±â€…19.31, P = .000). For octopus stone with a diameter of 2 to 4 cm, the effectiveness and safety of SM-PCNL combined with RIRS were similar to those of MSM-PCNL The surgeon should carefully evaluate the patient's physical condition, stone characteristics, and expectations before the operation and assist the patient in choosing an appropriate plan.

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.

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.

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.

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.

Navigating the complexities of a forgotten double J stent.

Double-J (DJ) stents are most commonly used urological tools these days. Serious complications may occur when stents are left in place for longer duration. We present a case of a woman in her 40s with a forgotten DJ stent for 4 years, leading to complications such as encrustations, bladder and renal stone formation. The patient underwent a comprehensive endourological approach, including endoscopic cystolithotomy and left-sided percutaneous nephrolithotomy. The case highlights the importance of timely stent removal to prevent complications such as encrustations and stone formation. Patient education and counselling are crucial to avoid poor compliance and the associated risks of forgotten stents. This case underscores the significance of a multidisciplinary approach and emphasises the need for proactive measures to prevent such complications, including the implementation of a stent placement registry.

An unusual case of an 0.018-inch (0.457 mm) guidewire fracture during primary percutaneous nephrostomy for percutaneous nephrolithotomy treated without removal and followed up for 5 years: A case report and literature review.

INTRODUCTION: Although rare, guidewire fractures can occur during interventional procedures. In most cases, the fractured guidewire segment can be removed. PATIENT CONCERNS: We report the case of a 54-year-old woman who experienced a guidewire fracture during percutaneous nephrostomy (PCN) for percutaneous nephrolithotomy to remove renal stones. DIAGNOSIS: Nephrolithiasis. INTERVENTIONS: PCN and percutaneous nephrolithotomy. OUTCOMES: In this case, the remaining segment could not be removed and caused inflammation and infection. However, her symptoms improved with inpatient treatment. Therefore, she was discharged from the hospital and followed up for 5 years. CONCLUSION: When performing PCN to remove renal stones, the possibility of a guidewire fracture must be considered. If resistance or scraping is felt while handling the guidewire, then it should be replaced.

Clinical comparison of lateral supine position mini-percutaneous nephrolithotomy and anatrophic nephrolithotomy in the treatment of complete staghorn renal calculi.

BACKGROUND: At present, the guidelines for urology recommend percutaneous nephrolithotomy (PCNL) as the preferred treatment for staghorn renal calculi (SRC). However, for complete SRC, it has been questioned by clinicians and patients due to high residual stone rate, complications, repeated hospitalizations and high treatment cost. Anatrophic nephrolithotomy (ANL) is a traditional and classic method for the treatment of SRC. Due to its high trauma and high technical requirements, it is difficult to carry out in primary hospitals, and gradually replaced by PCNL. The purpose of this study is to compare the efficacy of PCNL and ANL in the treatment of complete SRC. METHODS: Overall, 238 patients with complete SRC were divided into mini-PCNL in lateral supine position group, (n = 190) and ANL group (n = 94) according to treatment for a retrospective cohort study. The calculi parameters, renal function index, comorbidities of calculi, surgical complications, length and frequency of hospitalization, treatment costs, results of postoperative satisfaction survey were compared between the two groups. RESULTS: The risk of the residual stone rate after mini-PCNL in lateral supine position was 239 times (OR = 238.667, P < 0.0001), the number of residual stone 1.3 times (OR = 1.326, P < 0.0001), the amount of residual stone 2.2 times (OR = 2.224, P < 0.0001) that of ANL. The risk of the cost of initial treatment after mini-PCNL in lateral supine position was 3.3 times (OR = 3.273, P < 0.0001), the total cost of treatment 4 times (OR = 4.051, P < 0.0001), the total length of hospital stays 1.4 times (OR = 1.44, P < 0.0001) that of ANL, the incidence of postoperative renal atrophy was 2.2 times (OR = 2.171, P = 0.008) higher in the ANL than in the mini-PCNL in lateral supine position. Glomerular filtration rate (GFR) reduction after ANL was 1.4 times (OR = 1.381, P = 0.037) greater than that after mini-PCNL in lateral supine position at 24-month follow-up. The risk of the overall satisfaction of ANL was 58 times (OR = 57.857, P < 0.0001) higher than that of mini-PCNL in lateral supine position, the number of branches of staghorn greater than 8 is a high risk factor for the occurrence of residual stone after mini-PCNL in lateral supine position (OR = 353.137, P < 0.0001). CONCLUSION: Although the risk of renal atrophy and decreased GFR after ANL is higher than that of mini-PCNL in lateral supine position, the efficacy of traditional ANL in the treatment of complete SRC was generally superior to that of mini-PCNL in lateral supine position. Moreover, number of branches of staghorn greater than 8 are the preferred ANL for complete SRC. TRIAL REGISTRATION: ChiCTR2100047462. The trial was registered in the Chinese Clinical Trial Registry; registration date: 19/06/2021.

Changes in blood gas in supine and prone positions in percutaneous stone surgery: does position have any advantage for hemodynamics?

To evaluate whether different positions are advantageous for hemodynamics and respiratory balance in patients undergoing percutaneous nephrolithotomy (PCNL) procedures. Pre- and postoperative arterial blood gas data obtained during spontaneous breathing for 67 prone (Group 1) and 56 supine (Group 2) patients undergoing PCNL were analyzed. Additionally data on all patients' gender, age, body mass index, stone size, access and surgical duration, volume of irrigation fluid, length of hospital stay, requirement for blood transfusion, and residual stones were recorded: There were no differences between the groups in terms of age, stone size, operation time, access time, radiation exposure, transfusion requirements, stone-free rate, and length of hospitalization. A statistically significant pH decrease was observed in both groups in the postoperative period (p = 0.001 and p = 0.001, respectively). There was a statistically significant increase in pCO2 values in both groups in the postoperative period (p = 0.001 and p = 0.024, respectively), and that increase did not differ significantly between the groups (p = 0.624). A statistically significant decrease in pO2 and SpO2 values was observed in both groups in the postoperative period compared to the preoperative period. Again, no statistical difference was observed between the groups for these values. There was a statistically significant decrease in bicarbonate in both groups period (p < 0.001 and p = 0.001, respectively). Hemodynamics and the respiratory balance of the patient are impaired in both prone and supine positions. Neither position is superior to the other in this respect.

Robotic pyelolithotomy for treating large renal stone disease: a systematic review and single-arm meta-analysis.

Robotic pyelolithotomy continues to gain attention as an alternative to percutaneous nephrolithotomy (PCNL) for managing complex renal stones. We performed a single-arm meta-analysis and systematically searched the English-language literature published in PubMed, Web of Science, Scopus, and Google Scholar databases up to June 2024. The risk of non-randomized bias was assessed using ROBINS-I, and the quality of the literature was assessed using MINORS (Methodological Index for Non-Randomized Studies). Merger parameters were calculated using Stata16/SE under a random-effects model. Five non-comparative single-arm studies were included in the meta-analysis. Results showed that the operative time for robotic pyelolithotomy was 168.10 min (95% CI 133.63, 202.56). The hospital stay was 2.63 days (95% CI 0.96, 4.29), and blood loss was 44.13 ml (95% CI 19.76, 68.51). The stone clearance rate was 87% (95% CI 79-93%). The incidence of minor postoperative complications (Clavien grade I-II) was 23.7% (95% CI 13.4-35.8%), and the incidence of major complications (Clavien grade ≥ III) was 7% (95% CI 0.3-20.7%).The safety and efficacy of robotic pyelolithotomy in treating complex renal stones are acceptable, but future large prospective cohort studies are needed to validate the treatment.

A Comparative Study of Retrograde Intrarenal Surgery versus Percutaneous Nephrolithotomy for the Management of Staghorn Renal Calculi.

AIM: The indications for performing retrograde intrarenal surgery (RIRS) have increased. However, no comparative studies have been conducted on the treatment of staghorn renal calculi using RIRS and percutaneous nephrolithotomy (PCNL). We aimed to compare the effectiveness and safety of RIRS and PCNL as treatments for staghorn renal calculi. METHODS: We conducted a retrospective analysis of patients with staghorn renal calculi who underwent either PCNL or RIRS at our hospital from January 2021 to July 2023. Patients with staghorn renal calculi and renal malformation, as well as those with interrupted treatment or irregular follow-up, were excluded from the study. We compared the perioperative outcomes and complications between the groups. RESULTS: Fifty patients were included in the RIRS group, whereas 48 patients were included in the PCNL group. 1. No significant differences were observed between the groups regarding the number of complete staghorn calculi, stone size, age, sex, or other demographic characteristics. 2. RIRS was associated with a shorter postoperative hospitalization time (2.14 ± 0.76 vs. 5.15 ± 1.98 days, p < 0.001). 3. RIRS was associated with a decrease in hemoglobin (0.1 [0, 0.2] vs. 0.65 [0.4, 1] g/dL, p < 0.001) and a lower pain score (1 [1, 2] vs. 2 [1, 3], p = 0.008). 4. Compared with PCNL, RIRS did not significantly differ in terms of the 1-stage stone-free rate (50% vs. 66.67%, p = 0.095) or total stone-free rate (84% vs. 89.58%, p = 0.415). 5. The overall complication rate was lower in the RIRS group (10% vs. 16.67%, p = 0.331). CONCLUSIONS: Compared with PCNL, RIRS can reduce bleeding and overall complications, shorten the hospitalization time, and achieve satisfactory stone-free rate. As a result, RIRS can be considered an alternative treatment option for staghorn renal calculi.

High-risk patients for septic shock after percutaneous nephrolithotomy.

PURPOSE: to identify risk factors for urinary septic shock in patients who underwent percutaneous nephrolithotomy (PCNL). MATERIALS AND METHODS: Data from PCNL procedures performed between January 2009 and February 2020 were retrospectively analyzed. The study included all patients over 18 years old with kidney stones larger than 15 mm who underwent PCNL. Patients who underwent mini-PCNL or combined surgeries, such as ureteroscopy or bilateral procedures, were not included in the study. Logistic regression was conducted to determine the risk factors for urinary septic shock within 30 days post-operation in patients who underwent PCNL. RESULTS: Urinary septic shock was observed in 8 out of the 1,424 patients analyzed (0.56%). The presence of comorbidities, evaluated using the Charlson Comorbidity Index (CCI) (OR 1.46 [CI 95% 1.15-1.86], p=0.01), larger stones (41.0 mm [IQR 30.0-47.5 mm] vs. 24.0 mm [IQR 17.0-35.0 mm], OR 1.03 [CI 95% 1.01-1.06], p=0.04), and a positive preoperative urine culture (OR 8.53 [CI 95% 1.71-42.45], p < 0.01) were shown to significantly increase the risk of postoperative urinary septic shock. Patients with a CCI > 2, larger stones (≥ 35 mm), and a positive preoperative urine culture were at even higher risk of urinary septic shock (OR 15.40 [CI 95% 1.77-134.21], p=0.01). CONCLUSION: Patients with larger stones, positive preoperative urine culture, and a higher CCI are at risk for urinary septic shock after PCNL. These findings are of utmost importance for optimizing the perioperative care of these patients to prevent life-threatening complications.

Initial Clinical Experience With a Novel Robotically Assisted Platform for Combined Mini-Percutaneous Nephrolithotomy and Flexible Ureteroscopic Lithotripsy.

PURPOSE: We sought to evaluate the technical feasibility of performing a combined robotically assisted mini-percutaneous nephrolithotomy (PCNL) and flexible ureteroscopy (URS) procedure by a single urologist using the MONARCH Platform, Urology (Johnson & Johnson MedTech, Redwood City, California). MATERIAL AND METHODS: In this prospective, first-in-human clinical trial, 13 patients underwent robotically-assisted PCNL for renal calculi at the University of California-Irvine, Department of Urology. Successful completion of the procedure was assessed as the primary endpoint. Postoperative adverse events were monitored for 30 days following the completion of the procedure. Stone ablation efficiency was evaluated on postoperative day 30 with low-dose 2-3 mm slice CT scans. Patients were classified according to the maximum length of their residual stone fragments as either absolute stone-free (Grade A), < 2 mm remnants (Grade B), or 2.1-4.0 mm remnants (Grade C). RESULTS: The combined robotic mini-PCNL and URS procedure was successfully completed in 12 of 13 procedures. No robotic device-related adverse events occurred. Preoperative stone burden was quantified by both maximum linear measurement (median 32.8 mm) as well as by CT-based volume (median 1645.9 mm3). Using the unique robotically assisted targeting system, percutaneous access was gained directly through the center of the renal papilla in a single pass in all cases. Median operative time was 187 minutes (range: 83-383 minutes). On postoperative day 30, a 98.7% (range: 72.9%-100.0%) volume reduction was achieved, with 5 Grade A (38.5%), 1 Grade B (7.7%), and 2 Grade C (15.4%). Three patients experienced complications (2 grade 1 and one grade 2 Clavien-Dindo). CONCLUSIONS: Our preliminary investigation demonstrates the safety, efficacy, and feasibility of a unique robotic-assisted combined mini-PCNL and URS platform.

Which Position for Novice Surgeons? Effect of Supine and Prone Positions on Percutaneous Nephrolithotomy Learning Curve.

Background and Objectives: Percutaneous nephrolithotomy (PCNL) is a current treatment method with high success rates and low complication rates in treating large kidney stones. It can be conducted in different positions, especially supine and prone positions. PCNL in the supine position is becoming increasingly common due to its advantages, such as simultaneous retrograde intervention and better anesthesia management. This study aimed to assess how the choice of position impacts the PCNL learning curve. Materials and Methods: The results of the first 50 consecutive PCNL cases performed by two separate chief residents as primary surgeons in supine and prone positions in a reference center for stone treatment between August 2021 and January 2023 were evaluated. The two groups' demographic and clinical data, stone-free rates, operation times, and fluoroscopy times were compared. Results: While the mean operation time was 94.6 ± 9.8 min in the supine PCNL group, it was 129.9 ± 20.3 min in the prone PCNL group (p < 0.001). Median fluoroscopy times in the supine PCNL and prone PCNL groups were 31 (10-89) seconds and 48 (23-156) seconds, respectively (p = 0.001). During the operation, the plateau was reached after the 10th case in the supine PCNL group, while it was reached after the 40th case in the prone PCNL group. Conclusions: For surgeons who are novices in performing PCNL, supine PCNL may offer both better results and a faster learning curve. Prospective and randomized studies can provide more robust conclusions on this subject.