Concurrent two surgeon approach for bilateral synchronous percutaneous nephrolithotomy: Initial experience at a University Teaching Hospital

Percutaneous nephrolithotomy (PNL) has long been considered the bench-mark intervention for complicated urinary stones and has undergone important advancements since it was first described. Given the proven safety and efficacy of PNL, simultaneous bilateral PNL has been attempted for bilateral renal calculi to cut down on total procedure costs. To further cut down on operative time, concurrent bilateral synchronous PNL (BS-PNL) has been performed involving two surgeons, each operating concurrently on one renal unit. We performed a retrospective study to evaluate the safety and efficacy of BS-PNL in patients who consented for the procedure. Mean operative time taken from percutaneous access to skin closure was 78 min which was lower than that taken during the single surgeon approach for simultaneous bilateral PNL. Two (12%) out of 16 renal units required multiple punctures for stone clearance. Sheath size varied between 26Fr to 30Fr depending on the stone burden. Mean duration of hospital stay was 2 days. Fourteen (88%) out of 16 renal units had complete stone clearance. Fifteen (94%) out of 16 renal units had a double J stent placed for drainage. Only two patients had complications in the form of postoperative fever. In the background of already proven safety and efficacy of SB-PNL, the concurrent two surgeon approach appears to be feasible and safe with additional advantage of reduced operative time. However, the number of patients in this series were limited and a bigger and preferably multi-institutional study would be required before we can come to a definitive conclusion.

2022 Recommendations of the AFU Lithiasis Committee: Percutaneous nephrolithotomy

Percutaneous nephrolithotomy (Labate et al.) is the standard procedure for the treatment of large (≥2cm) kidney stones. The patient can be in prone or modified supine position. The puncture is performed under fluoroscopy and/or ultrasound guidance. The stone-free rate seems to be comparable between miniaturized and standard PCNL. Procedures performed with smaller diameter instruments tend to be associated with significant lower blood loss, but longer procedure times. The limitation of the number of percutaneous tracts results in better preservation of the kidney function and lowers the risk of complications. The use of tranexamic acid during PCNL may be interesting for reducing the bleeding risk, the transfusion rate, and possibly the intervention duration. METHODOLOGY: These recommendations were developed using two methods: the Clinical Practice Recommendation (CPR) method and the ADAPTE method, depending on whether the question was considered in the European Association of Urology (EAU) recommendations (https://uroweb.org/guidelines/urolithiasis [EAU 2022]) and their adaptability to the French context.

Analysis of the Risk Factors for Massive Hemorrhage after PCNL in the Oblique Supine Position

BACKGROUND

Percutaneous nephrolithotomy (PCNL) is a proven and efficient treatment method; Nevertheless, it is essential to note that there is still a risk of significant bleeding. The purpose of this paper is to explore the risk factors for massive hemorrhage after PCNL in the oblique supine position and provide a basis for the development of measures to prevent massive hemorrhage.

METHODS

The clinical data of 97 patients who underwent PCNL in the oblique supine position at Changshu No. 2 People's Hospital from January 2019 to December 2020 were retrospectively analyzed. Patients were placed in the massive hemorrhage group if their hemoglobin levels decreased by ≥20 g/L 24 h after the operation, and the other patients were placed in the nonmassive hemorrhage group. Differences in sex, age, body mass index (BMI), hypertension, diabetes, surgical side, perirenal fat stranding (PFS), calculus long diameter, surgical access, and operation time were compared between the two groups to determine the risk factors for massive bleeding. Multivariable logistic regression analysis was used to determine the risk factors for massive hemorrhage after PCNL.

RESULTS

There were no significant differences in sex, BMI, hypertension, diabetes, surgical side, or calculus long diameter between the two groups (p > 0.05), and there were statistically significant differences in age, PFS, surgical access, and operation time (p < 0.05). Multivariate logistic regression analysis indicated that PFS and extensive surgical access were independent risk factors (p < 0.05).

CONCLUSIONS

PFS and extensive surgical access were independent risk factors. Carefully reading computed tomography (CT) films before surgery and reducing the size of the surgical access area are important measures for reducing the risk of massive hemorrhages.

Needle-perc-assisted endoscopic surgery (NAES) for patients with complicated solitary kidney stones: a prospective randomized study from a single center

PURPOSE

The goal of this study is to compare traditional percutaneous nephrolithotomy (PCNL) and needle-perc-assisted endoscopic surgery (NAES) in the treatment of complicated solitary kidney stones via a single-center randomized controlled prospective study.

METHODS

A total of patients with complex (Guy's score II-IV) solitary kidney stones between July 2019 to June 2022 were enrolled in the study. Participants were stratified into two groups: needle-perc-assisted endoscopic surgery group (group A) and traditional PCNL group (group B). All procedures were finished by X-ray free technique. The clinical characteristics and outcomes were analyzed.

RESULTS

A total of 90 (44 in Group A and 46 in Group B) patients were finally included in our study. There were no statistically differences in terms of gender, age, body mass index (BMI), stone burden between two groups. The mean operative duration of Group A was significant higher than group B (95.1 ± 21.4 min vs 72.5 ± 29.5 min, p=0.02). The 1-month stone-free rate (SFR) was significant higher in Group A than B (90.9% vs 73.9%, p=0.03). A less hemoglobin drop (p=0.01), shorter postoperative in-hospital day (p=0.04), and lower severe complication (Clavien-Dindo III and above) rates (p=0.03) were observed in Group A.

CONCLUSION

For patients with solitary kidney stones, NAES technique provides a higher one-session SFR, a better renal function recovery and compared with traditional PCNL.

Modified biplanar (0-90°) endoscopic-guided puncture technique for percutaneous nephrolithtomy: refinement with endoscopic combined intrarrenal surgery to reduce fluoroscopy and operative time

INTRODUCTION

We aim to publish our innovative modified biplanar 0-90 endoscopic guided puncture technique for percutaneous nephrolithotomy in supine recorded with a GoPro® camera for standardization of the technique. It solves drawbacks of the fluoroscopic technique, i.e., in kidneys with complex anatomy, it may be challenging to distinguish calyces as they are often superposed, and it does not allow for all benefits of a combined endoscopic approach (1, 2). Our technique shortens puncture and fluoroscopic time and is easy to teach and reproduce.

METHODS

A 77-year-old female patient had previous double J insertion due to an obstructing stone in the right distal ureter. She managed to pass the distal stone but remained with the double J and a 20mm stone (1300HU) in the right renal pelvis. The shared decision was for the actual standard of care (3, 4) endoscopic combined intrarenal surgery (ECIRS). The MiniECIRS started with flexible ureteroscopy and a posterior calix which gave direct access to the stone was chosen. The tip of the flexible scope was used to mark point A with the C-arm in the 0-degree position and line B in the 90-degree position. Puncture was fast and the MiniECIRS was uneventful with a single mid-pole access guided by the flexible scope. The surgeon had a Full-HD GoPro® camera mounted on his head, controlled by the surgical staff. All essential surgical steps were recorded.

RESULTS

The quality of the recorded movie was graded as excellent, and the camera did not cause any discomfort to the surgeon. Operative and X-Ray time were 120minutes and 2minutes (7.64mGy). Hemoglobin drop was 0.8g/dL. The post-operative day-1 computed tomography scan was stone-free. The patient was discharged 24h after surgery. Kidney stent was left with a string and removed after 5days. The patient remained asymptomatic and metabolic evaluation revealed a calcium oxalate stone, low urinary volume and hypocitraturia which were treated with potassium citrate and hydration.

CONCLUSION

The Modified Biplanar (0-90 degree) Endoscopic-Guided Puncture Technique for Percutaneous Nephrolithotomy joins the reproducibility of the same technique under fluoroscopy with advantages regarding safety and efficiency of ECIRS.

A comparative analysis of the efficacy and safety of mini-percutaneous nephrolithotomy performed in the supine and prone positions for the treatment of pediatric kidney stones: a single-center experience

Mini-percutaneous nephrolithotomy (MPCNL), which has a smaller tract size (14-20 Fr) than conventional percutaneous nephrolithotomy, has been shown to be safe and effective in pediatric patients with large and complex upper urinary tract stones. This study aimed to compare the efficacy and safety of MPCNL between the supine and prone positions in a pediatric population. The data of pediatric patients who underwent MPCNL at our center between January 2010 and March 2023 were retrospectively analyzed. According to the surgical position, the patients were divided into the prone (Group P) and supine (Group S) groups. In both groups, dilatation was performed using 14-18 Fr metallic dilators. The two groups were compared in terms of perioperative data, postoperative stone-free rates (SFRs), and complications. There were 36 (59%) patients in Group P and 25 (41%) patients in Group S. Stones were mostly located in the pelvis (49.2%) and second most frequently in the lower pole (27.9%). Fluoroscopy time was shorter in Group S but did not statistically significantly differ compared to Group P (p = 0.181). However, operation time was statistically significantly shorter in Group S (73.8 ± 35 vs. 99.8 ± 37.4 min, p = 0.008). Although there was no significant difference, relatively higher SFR were detected in Group S (88% vs. 83%, p = 0.725). Endoscopic combined intrarenal surgery (ECIRS) was performed on six (24%) patients in Group S, and the SFR was 100% among these patients. There was no significant difference between the two groups in terms of the presence of complications (16.7% vs. 16%, p = 0.945). Both supine and prone MPCNL appear to be safe and effective in the pediatric age group, with similar stone-free and complication rates. In the supine procedure, the operation time is shortened compared to the prone. In addition, simultaneous retrograde access has the potential to increase the overall success rate of surgery.

Comparison of endoscopic versus CT assessment of stone-free status after percutaneous nephrolithotomy (PCNL)

This study is aimed to determine whether postoperative low dose computed tomography (LDCT) imaging is necessary after percutaneous nephrolithotomy (PCNL), or the surgeon's intraoperative assessment of residual fragments (RF) is sufficient and avoidance of postoperative imaging with reduction of radiation exposure can be achieved. Data of all 610 patients who underwent PCNL in prone position in our institution from February 2009 to September 2020 was collected. Parameters such as age, gender, BMI, ASA-Classification, stone related parameters and the surgeon's assessment of stone-free status were analyzed. The LDCT performed postoperatively was compared to the intraoperative assessment of the surgeon regarding RF. The mean age of patients was 52.82 years; the mean BMI was 28.18 kg/m2. In 418 cases, the surgeon made a clear statement about the presence of RF and postoperative LDCT was carried out. The discrepancy between the two methods (surgeon´s assessment vs. LDCT) was significant at p < 0.0001. The sensitivity, specificity, positive and negative predictive value of the surgeon when assessing RF were 24.05%, 99.45%, 98.28% and 50%. Stone free rate (SFR) after primary PCNL was 45.57%. The overall SFR at discharge was 96.23%. Although the surgeon´s assessment of RF was reliable, postoperative LDCT imaging should still be performed if endoscopic stone clearance is suspected due to the high false negative rate and the low negative predictive value. The optimal timing of postoperative imaging following PCNL remains unclear.

Interdisciplinary planning improves radiologist obtained access for percutaneous nephrolithotomy

INTRODUCTION

Proper antegrade access for percutaneous nephrolithotomy (PCNL) is essential for success but can be challenging. Previous work evaluating access obtained by interventional radiology (IR), largely in the emergent setting, has shown high rates of additional access at the time of PCNL. We hypothesize that efforts to improve pre-procedural communication between urology and IR can impact the utility of the access for subsequent PCNL.

MATERIAL AND METHODS

We conducted a retrospective review of patients undergoing PCNL at a single hospital from January 2011 to December 2022. Adult patients undergoing PCNL with established preoperative access were included.

RESULTS

A total of 141 cases were identified with preoperative access. A total of 111 patients had evidence of planning with IR prior to antegrade access. There were high rates of anatomic abnormality (50%) and staghorn calculus (53%). Patients with planned access had higher body mass index (BMI). While preoperative access was initially utilized in 97% of cases, 6% required additional access to be obtained intraoperatively; this included a low rate of new access in those that were previously discussed with IR (4% vs. 17%, p = 0.02). Overall stone free rates (91%), rates of second stage procedures (55%) and complications (14%) were similar between planned and unplanned groups.

CONCLUSION

In this retrospective study of complex patients with large stone burden presenting for PCNL with preoperative antegrade access obtained by IR, the rate of new access was far lower than prior reports. This was likely influenced by urologist involvement in planning access.

Percutaneous Nephrostomy in Neonates and Young Infants

PURPOSE

To describe a single-center experience of placing percutaneous nephrostomy (PCN) tubes in neonates and young infants aged ≤3 months.

MATERIALS AND METHODS

This retrospective study evaluated PCN placement during a 19-year period. Medical records were reviewed for patient demographics, indications, procedure details, catheter-related adverse events, and outcomes. A total of 45 primary PCN insertions were attempted in 29 children (median age, 11 days [range, first day of life to 3 months]; median weight, 3.5 kg [range, 1.4-7.0 kg]). Salvage procedures resulted in 13 secondary catheters in 6 children. The most common indication was ureteropelvic junction obstruction (40.0%), and the most common urinary tract dilation classification was P3 (88.9%).

RESULTS

Technical success for primary placements was 95.6%; both technical failures were due to loss of access in the same patient. Of primary placements, 76.7% were electively removed, 6.9% were dislodged but not replaced, and the remaining 16.3% required salvage procedures. Mechanical adverse events occurred in 20.9% of primary and 53.8% of secondary catheters, including partial retraction, complete dislodgement, and occlusion. Urinary tract infections (UTIs) occurred in 18.6% of primary and 15.4% of secondary catheters. Urosepsis occurred in 2.3% of primary and 7.7% of secondary catheters. Median primary catheter dwell time was 41 days (range, 1-182 days) and median secondary catheter dwell time was 31 days (range, 10-107 days).

CONCLUSION

PCN placement in neonates and young infants has a high technical success rate, although not without particular procedural and management challenges of catheter malfunction and UTI.

Comparison of hemodynamic and respiratory outcomes between two surgical positions for percutaneous nephrolithotomy: a prospective, randomized clinical trial

INTRODUCTION

Percutaneous nephrolithotomy (PCNL) has become the gold standard for the treatment of large and complex kidney stones.

OBJECTIVES

The objective of this study is to evaluate the efficacy and safety of percutaneous nephrolithotomy (PCNL) for patients in the flank position versus prone position.

METHODS

In our prospective randomized trial, 60 patients who would undergo fluoroscopy and ultrasound-guided PCNL in prone or flank position were divided into two groups. Demographic features, hemodynamics, respiratory and metabolic parameters, postoperative pain scores, analgesic requirements, amount of fluid given, blood loss and transfusion, duration of operation and hospital stay, and perioperative complications were compared.

RESULTS

PaO2, SaO2, SpO2 and Oxygen Reserve İndex (ORi) at the 60th minute of the operation and in the postoperative period, Pleth Variability index (PVi) at the 60th minute of the operation, driving pressure in all time periods and the amount of bleeding during the operation were determined to be statistically significantly higher in the prone group. There was no difference between the groups in terms of other parameters. Was found to be statistically significantly higher in the prone group.

CONCLUSIONS

Due to our results the flank position can be preferred in PCNL operations, considering that the position should be chosen according to the surgeon's experience, the patient's anatomical and physiological data, positive effects on respiratory parameters and bleeding, and the operation time can be shortened as the experience increases.

Stone clearance and complication rate of micro percutaneous nephrolithotomy and retrograde intrarenal surgery for lower pole renal stone: A randomized trial

Background

The use of unhealthy food and a sedentary lifestyle increases daily health problems. Renal stones are one among others. Endourology promises the minimum complications and the highest stone clearance rate. Indications of the two procedures overlap micro-PCNL and RIRS. The objective was to evaluate stone clearance and complication rate of micro-PCNL and RIRS for lower pole renal stones.

Methods

The research design of this study was a randomized trial and was done after approval of the ethical review committee. The sampling technique was consecutive sampling at the Urology department. Patients included in the study according to inclusion criteria were 96 in number. Randomization into two groups (RIRS vs micro-PCNL) was done by even odd method. All the procedure was done by a single senior urologist.

Results

Their ratio among males and females was 2:1. Mean LOS in the RIRS group was 2.89±0.86 days and in the micro-PCNL group 2.58±0.65 days (p=0.047). The complication rate in the RIRS group was 6.2% and 8.3% in micro-PCNL (p=0.695). Mean post-operative haemoglobin was 12.30±1.07 g/dL among the RIRS group and among the micro-PCNL group it was 11.21±1.08 g/dL (p<0.001). There was an average haemoglobin drop in the micro-PCNL group of 1.09±0.01 g/dL. 75% clearance of stone after one session was achieved in the RIRS group while 79.2% was achieved in the micro-PCNL group (p=0.627).

Conclusion

Length of hospital stay (LOS) and stone clearance rate (SFR) were similar in both groups with insignificant statistical differences. There is a need to conduct more studies with a large number of study participants and involving multi-centers.

Chinese mini percutaneous nephrolithotomy for upper urinary calculi under local infiltration anesthesia

Percutaneous nephrolithotomy is generally performed under general or regional anesthesia; however, it is rarely performed under local infiltration anesthesia (LIA). This study aimed to assess the safety and effectiveness of Chinese mini percutaneous nephrolithotomy (MPCNL) for upper urinary calculi under LIA. A retrospective analysis of 52 patients with upper urinary stones who underwent MPCNL under LIA from April 2019 to May 2022 was performed. Pethidine and Phenergan were intramuscularly injected 30 minutes preoperatively. Oxybuprocaine hydrochloride gel was applied to the urethra for lubricating and mucosal anesthesia. Ropivacaine hydrochloride and lidocaine were injected into the whole percutaneous channel for local anesthesia. An 8/9.8F ureteroscope and an 18F vacuum-assisted access sheath were applied in MPCNL. All 52 patients tolerated procedures and underwent operations successfully; none of them converted the anesthesia method or required additional analgesia. The mean visual analogue scale scores intraoperatively and at 6 hours, 24 hours, and 48 hours after surgery were 3.25 ± 0.52, 3.13 ± 0.69, 2.25 ± 0.56, and 1.58 ± 0.50, respectively. The stone free rate was 84.6%. Complications were seen in 6 (11.5%) patients, including fever in 2 patients (Clavien I), renal colic in 1 patient (Clavien I), clinically insignificant bleeding in 2 patients (Clavien I), and urinary tract infection in 1 patient (Clavien II). No severe complications were observed in any patients. Chinese MPCNL under LIA was a feasible option and achieved good outcomes in appropriately selected patients, and it may become the routine procedure for general patients.

A multicenter study on the application of artificial intelligence radiological characteristics to predict prognosis after percutaneous nephrolithotomy

Background

A model to predict preoperative outcomes after percutaneous nephrolithotomy (PCNL) with renal staghorn stones is developed to be an essential preoperative consultation tool.

Objective

In this study, we constructed a predictive model for one-time stone clearance after PCNL for renal staghorn calculi, so as to predict the stone clearance rate of patients in one operation, and provide a reference direction for patients and clinicians.

Methods

According to the 175 patients with renal staghorn stones undergoing PCNL at two centers, preoperative/postoperative variables were collected. After identifying characteristic variables using PCA analysis to avoid overfitting. A predictive model was developed for preoperative outcomes after PCNL in patients with renal staghorn stones. In addition, we repeatedly cross-validated their model's predictive efficacy and clinical application using data from two different centers.

Results

The study included 175 patients from two centers treated with PCNL. We used a training set and an external validation set. Radionics characteristics, deep migration learning, clinical characteristics, and DTL+Rad-signature were successfully constructed using machine learning based on patients' pre/postoperative imaging characteristics and clinical variables using minimum absolute shrinkage and selection operator algorithms. In this study, DTL-Rad signal was found to be the outstanding predictor of stone clearance in patients with renal deer antler-like stones treated by PCNL. The DTL+Rad signature showed good discriminatory ability in both the training and external validation groups with AUC values of 0.871 (95% CI, 0.800-0.942) and 0.744 (95% CI, 0.617-0.871). The decision curve demonstrated the radiographic model's clinical utility and illustrated specificities of 0.935 and 0.806, respectively.

Conclusion

We found a prediction model combining imaging characteristics, neural networks, and clinical characteristics can be used as an effective preoperative prediction method.

[Mini-PCNL, micro-PCNL or RIRS: comparative efficacy and safety in renal stones up to 2 cm]

INTRODUCTION

One of the main trends in the evolution of endoscopic treatment of urolithiasis is the miniaturization of instruments. This is obvious in the development of minimally invasive percutaneous nephro-lithotomy (PCNL) and retrograde intrarenal surgery (RIRS). However, there are few studies comparing the efficiency and safety of these methods.

AIM

To evaluate and compare the efficiency and safety of mini-PCNL, micro-PCNL and RIRS in the treatment of kidney stones up to 2 cm in size.

MATERIALS AND METHODS

Between October 2020 and December 2022, a total 72 patients underwent minimally invasive endoscopic procedures in two centers, including RIRS (n=30), mini-PCNL (n=26) and micro-PCNL (n=16) using thulium fiber laser FiberLase U2. The efficiency of procedure (stone free rate [SFR]) was assessed using non-contrast-enhanced CT. SFR was considered as the absence of residual fragments > 4 mm. Complications (safety) were evaluated based on the Clavien-Dindo classification.

RESULTS

The mean age of all patients was 47.7 (22-84) years. There were no significant differences between three groups in stone characteristics according to CT (maximum diameter, density, volume and number of stones, the presence of pelvicalyceal dilation). SFR was significantly different between the groups (p=0.034). The overall SFR was 81.9% (n=59). After RIRS, mini-PCNL, and micro-PCNL the SFR was 93.3%, 80.8%, and 62.5%, respectively. A significant difference was found between the RIRS and micro-PNL groups, with 2 out of 30 and 6 out of 16 patients requiring repeat procedure, respectively (p=0.026). The overall rate of complication of grades I-II, IIIa and IIIb according to Clavien-Dindo was 6.9%, 9.7% and 6.9%, respectively. A significant difference was found between the RIRS and micro-PCNL (p=0.021) for grade I-II complications. A rate of grade III complications was not differed between the groups. The operation time was higher for mini-PNL (79.8 (30-145) min), and it was shorter for RIRS (55.7 (30-155) min). The length of stay was lower in RIRS group (4.5 (1-12) days).

CONCLUSION

The highest SFR was achieved in the RIRS group. In terms of the number of complications of I-II grades according to Clavien-Dindo, the duration of the procedure and the length of stay, RIRS also showed the advantage. There were no significant differences in efficiency and safety between the micro-PNL and mini-PNL. There are not enough studies comparing minimally invasive methods for treating kidney stones. It is necessary to continue research in this area in order to develop an optimal algorithm for choosing the method of endoscopic treatment.

Initial results of the implementation of an ambulatory mini percutaneous nephrolithotomy program

OBJECTIVE

To present our program for ambulatory mini percutaneous nephrolithotomy (mini-PCNL) and evaluate its initial results.

MATERIAL AND METHODS

We analyzed the implementation of the protocol into the clinical practice with the first 30 outpatient mini-PCNL cases performed in our center between April 2021 and September 2022. Demographic characteristics, perioperative variables, complications and need for unplanned health care, stone-free rate (SFR), stone type and patient satisfaction with the major ambulatory surgery (MAS) process were collected.

RESULTS

A total of 30 patients with a mean age of 60.2 ± 11.6 years who met the inclusion criteria underwent surgery. The mean stone size was 15 mm [range: 5-20]. No intraoperative complications were recorded. All patients except one were discharged the same day of surgery as planned. In the month following discharge, the rate of complications, emergency department (ED) revisits or hospital readmissions rates were 0%. Stone-free-rate (SFR) at 3 months was 83%. Overall satisfaction with the whole perioperative process was assessed with the EVAN-G questionnaire, obtaining 124.3 points out of a maximum of 150, which is equivalent to a 78.6% level of satisfaction.

CONCLUSION

Ambulatory mini-PCNL can be implemented as a treatment option in centers with experience in endourology, an established MAS Unit, and strictly selected patients. Our initial results show an adequate safety profile and high overall satisfaction perceived by patients undergoing the ambulatory approach.

Application of Bipolar Cauterization During Standard Percutaneous Nephrolithotomy

Introduction: We aimed to evaluate the efficacy of bipolar cauterization for tract site bleeding during standard percutaneous nephrolithotomy (PCNL). Methods and Materials: We defined tract site bleeding as when the visual field across the parenchymal tract starts to bleed while the sheath of a balloon dilator is being withdrawn just before the operation is completed. Among 181 patients, 90 patients showed no significant bleeding, and 91 patients required further procedures to resolve tract site bleeding. In cases of unresolved tract site bleeding, either nephrostomy placement (n = 60) or cauterization (n = 31) was performed. The outcomes of three groups (no procedure group, nephrostomy group and cauterization group) were compared. Results: The median decrease in hemoglobin at 2-hour intervals postoperatively was -1.75, -1.0, and -0.2 in the nephrostomy, cauterization, and no procedure groups, respectively (P < .001). There were 25 patients (41.7%) who received transfusions in the nephrostomy group, whereas only 1 patient (3.2%) received a transfusion in the cauterization group (P < .001). Conclusion: The bipolar cauterization of bleeding points at the end of PCNL could efficiently decrease tract site bleeding and reduce the need for transfusion. Clinical Research Information Service (https://cris.nih.go.kr/cris; No. KCT0008303).

Anatomical approach to PCNL: concept of ideal puncture zone in a 3D perspective

To describe a concept of ideal 'puncture zone' as against any single ideal 'puncture tract' for percutaneous nephro-lithotomy (PCNL) and present our results. Through this narrative, we aim to reduce the gaps in inter-understanding of an erstwhile description of ideal tract and real-life puncture making. The puncture zone principle was applied for our novel puncture making technique during PCNL. The largest imaginary cone that can fit into a respective calyx, with its tip in the pelvis defines the 'puncture zone' for that calyx. This concept allows fine-tuning of the ideal puncture tract based upon the desired corresponding manipulation zone and also shifts the focus of puncture making to infundibulum anatomy from the tip of calyx. The surgical technique and retrospective review of 136 cases done between 2015 and 2021 using this concept are presented. Primary outcome included stone-free rate, pseudo-aneurysm and blood transfusion at 3 months of follow-up. 33 cases had multiple (> 3) stones, 21 only calyceal/infundibular stones, eight partial staghorn and 12 were complete staghorn stones. Mean stone size was 29 ± 15 (Range: 5-53) mm. Complete clearance was achieved in 127 cases, four of which required two tracts. Blood transfusion was required in one case. No pseudo-aneurysms were encountered. The puncture zone concept has provided good results in our hands. It may help easier understanding of PCN puncture making and provides a background for reconciliation between description of an ideal tract and practical puncturing techniques used by different surgeons.

Post-operative pain following percutaneous nephrolithotripsy- clinical correlates

OBJECTIVES

Management of postoperative pain following percutaneous nephrolithotripsy (PCNL) is a significant goal. We sought to identify risk factors and clinical correlates of postoperative pain in order to improve perioperative management and patient satisfaction.

MATERIALS AND METHODS

A single-center, retrospective analysis, from a prospectively maintained database, of all consecutive patients who underwent PCNL for renal calculi between January 2011 and August 2018. Postoperative pain was assessed using the visual analog scale (VAS) and analgesic use. We considered VAS score above 4 as meaningful. Pain management was standardized according to patirnt reported VAS scores. Multivariable logistic regression was performed to identify risk factors and clinical correlates.

RESULTS

A total of 496 patients were analyzed. Younger age was associated with VAS above 4 on the operative day and the first postoperative following PCNL (p = 0.003 and p < 0.001, respectively). Female gender was associated with VAS above 4 in the first 2 days following the operation (p < 0.001).

CONCLUSIONS

Younger age and female gender would most likely benefit from pre-emptive improved pain management protocols following PCNL.

A randomised controlled trial comparing two protocols of preoperative antibiotics in patients with positive urine culture undergoing percutaneous nephrolithotomy

AIM

To compare the outcomes of two different protocols of antibiotic prophylaxis in patients with positive urine culture undergoing percutaneous nephrolithotomy (PCNL).

MATERIALS AND METHODS

Patients were prospectively enrolled for the randomised study to either group A which included patients where an attempt to sterilise the urine was made with a 1 week course of sensitive antibiotics or group B that included patients who received a shorter duration of prophylaxis using sensitive antibiotics for 48 h prior to procedure which was continued for 48 h postoperatively. Enrolled patients had stones requiring percutaneous nephrolithotomy and had a positive preoperative urine culture. Primary outcome was difference in sepsis rates between the groups.

RESULTS

A total of 80 patients randomised into two groups of 40 each based on the antibiotic protocol used were analysed in the study. There was no difference in infectious complication rates between groups on univariate analysis. The rate of SIRS in Group A and Group B was found to be 20% (N = 8) and 22.5% (N = 9) respectively. The rate of septic shock in Group A and Group B was 7.5% and 5% respectively. On multivariate analysis, longer duration of antibiotics did not decrease the risk of sepsis compared to shorter antibiotic course (p = 0.79).

CONCLUSION

Attempts to sterilise urine before PCNL may not decrease the risk of sepsis in patients with positive urine culture undergoing PCNL and may only result in unnecessary prolonging of antibiotic usage thereby increasing the chances of antibiotic resistance.

A Novel Computed Tomography-Ultrasound Image Fusion Technique for Guiding the Percutaneous Kidney Access

PURPOSE

To describe the feasibility of computed tomography (CT)-ultrasound image fusion technique on guiding percutaneous kidney access in vitro and vivo.

MATERIALS AND METHODS

we compare CT-ultrasound image fusion technique and ultrasound for percutaneous kidney puncture guidance by using an in vitro pig kidney model. The fusion method, fusion time, ultrasound screening time, and success rate of puncture were compared between the groups. Next, patients with kidney stones in our hospital were randomized in the study of simulated puncture guidance. The general condition of patients, fusion method, fusion time, and ultrasound screening time were compared between the groups.

RESULTS

A total of 45 pig models were established, including 23 in the CT-ultrasound group and 22 in the ultrasound group. The ultrasound screening time in the CT-ultrasound group was significantly shorter than that in the ultrasound group (P < .001). In addition, the success rate of puncture in the CT-ultrasound group was significantly higher than that in the ultrasound group (P =.015). Furthermore, in the simulated PCNL puncture study, baseline data including age, BMI, and S.T.O.N.E score between the two groups showed no statistical difference. The ultrasound screening time of the two groups was (2.60 ± 0.33) min and (3.37 ± 0.51) min respectively, and the difference was statistically significant (P < .001).

CONCLUSION

Our research revealed that the CT-ultrasound image fusion technique was a feasible and safe method to guide PCNL puncture. Compared with traditional ultrasound guidance, the CT-ultrasound image fusion technique can shorten the learning curve of PCNL puncture, improve the success rate of puncture, and shorten the ultrasound screening time.

Retrograde intrarenal surgery for stones associated with renal anomalies: caliceal diverticulum, horseshoe kidney, medullary sponge kidney, megacalycosis, pelvic kidney, uretero-pelvic junction obstruction

PURPOSE OF REVIEW

Nowadays, due to the increase of imaging diagnosis, we identify easily renal anomalies, and we can choose between a wide range of armamentarium to treat symptomatic stones in those challenging cases. However, there is a lack of evidence and consensus on its use. The aim of this narrative review is to collect all the available data about safety and efficacity of retrograde intrarenal surgery (RIRS) in the treatment of kidney stones associated to a renal anomaly.

RECENT FINDINGS

Renal anomalies are uncommon findings and even more if it has to be associated with renal stones. After a literature review of the past 2 years, there are a small number of studies that compare the outcomes in patients who have been treated with minimally invasive modalities and they are mainly focus on RIRS.

SUMMARY

It is of extreme importance to know the advances on the stone treatment in anomalous kidneys. With the development of new laser technologies, RIRS is becoming a more interesting technique with high success rate and safety. Further studies are needed to make an accurate statement about the adequate surgical technique for each renal anomaly and also, clinical trials using new laser technologies.

Quality Improvement of Surgical Team Communication of Required Percutaneous Nephrolithotomy Equipment

OBJECTIVE

To evaluate if implementation of a percutaneous nephrolithotomy (PCNL) equipment whiteboard can improve communication accuracy of surgical equipment, streamline operative efficiency, and decrease unnecessary case equipment costs.

METHODS

A real-time editable equipment whiteboard was designed and implemented for all PCNL cases between October and December 2021. The relative difference in pre- and post-intervention surgical equipment accuracy as well as overall case costing was compared from 90 days prior to implementation to the period after intervention.

RESULTS

Quality assessment surveys were completed prior to whiteboard implementation (N = 25) and cost implementation (n = 15). Pre- and postoperative assessment of equipment communication, assessed on a 10-point scale, improved after implementation of the communication whiteboard (Pre-op: 6.7/10 vs. 8.9/10, P < .001. Post-op: 7.0/10 vs. 9.3/10, P < .001). On average 64% (3.2/5) of items were accurate on preintervention cases. Postintervention accuracy improved to 88% (4.4/5 items) (P = .049). There was a significant relative case cost improvement after implementing the PCNL equipment whiteboard with an average of $436.81 USD savings per case (P = .001) and $488.22 USD per renal moiety (P = .002).

CONCLUSION

Our baseline quality assessment of surgical team communication regarding PCNL equipment identified an area for improvement. Multidisciplinary feedback resulted in the development of a real-time editable PCNL equipment whiteboard which improved team perception of equipment communication, case item accuracy and resulted in a relative average cost savings for PCNL.

A comparison of adverse pregnancy events between ureteral stents and percutaneous nephrostomy tubes in the treatment of nephrolithiasis during pregnancy: A propensity score-matched analysis of a large multi-institutional research network

PURPOSE

To investigate rates of adverse pregnancy events associated with the use of percutaneous nephrostomy tubes (PCN) versus ureteral stents in the treatment of nephrolithiasis during pregnancy.

METHODS

We queried the TriNetX Diamond Network database to evaluate pregnant women (ICD-10 Z34, O09) with a history of nephrolithiasis (N20-23) who underwent a PCN (CPT 50432) or ureteral stent (52332) placement up to 6 months before delivery (O80-82). We controlled for the following potentially confounding variables through propensity score matching: age, race, ethnicity, acute pyelonephritis (N10), infections of the genitourinary tract in pregnancy (O23.0), and other sepsis (A41) at the time of stent or PCN placement.

RESULTS

We identified 2,999 pregnant women who underwent ureteral stent placement and 321 who underwent PCN. Following propensity score matching, we found there to be no significant difference in the rate of premature labor or delivery (aOR 1.08, 95% CI 0.735-1.588), premature rupture of membranes (0.889, 0.453-1.743), intrauterine infection (0.906, 0.379-2.165), or c-Sect. (0.825, 0.408-1.667). Within 6 months of their initial procedure, women with a ureteral stent experienced a significantly decreased rate of subsequent urinary tract infection (UTI) or pyelonephritis (0.52, 0.38-0.71), inpatient hospital stay (0.40, 0.26-0.64), emergency department visit (0.65, 0.48-0.89), and repeat exchange procedure (0.70, 0.51-0.96).

CONCLUSION

In the treatment of nephrolithiasis during pregnancy, PCN versus ureteral stent placement does not confer a significant difference in rates of adverse pregnancy events. However, ureteral stent placement was associated with a lower incidence of hospital admissions, emergency department visits, exchange procedures, and new UTIs or pyelonephritis.

Optimizing stone harvesting in miniaturized-PCNL: a critical examination of renal access angles, technology, and the role they play in operative efficiency

PURPOSE

Stone retrieval can be a laborious aspect of percutaneous nephrolithotomy (PCNL). A unique phenomenon of mini-PCNL is the vortex-effect (VE), a hydrodynamic form of stone retrieval. Additionally, the vacuum-assisted sheath (VAS) was recently developed as a new tool for stone extraction. The purpose of our study is to investigate the impact of renal access angle (as a surrogate for patient positioning) on stone retrieval efficiency and compare the efficiency among methods of stone retrieval.

METHODS

A kidney model was filled with 3 mm artificial stones. Access to the mid-calyx was obtained using a 15Fr sheath. Stones were retrieved over three minutes at angles of 0°, 25°, and 75° utilizing the VE, VAS, and basket. Stones were weighed for comparison of stones/retraction and stones/minute. Trials were repeated three times at each angle.

RESULTS

Renal access angle of 0° was associated with increased stone retrieval for both the VE and VAS (p < 0.05). The VE was the most effective method for stones retrieved per individual retraction at an angle of 0° (p < 0.005), although when analyzed as stones retrieved per minute, the VE and VAS were no longer statistically different (p = 0.08). At 75°, none of the methods were statistically different, regardless if analyzed as stones per retraction or per minute (p = 0.20-0.40).

CONCLUSIONS

Renal access angle of 0° is more efficient for stone retrieval than a steep upward angle. There is no difference in stone retrieval efficiency between the VE and VAS methods, although both are superior to the basket at lower sheath angles.

Percutaneous management of caliceal diverticula: a narrative review

PURPOSE OF REVIEW

Caliceal diverticula are relatively uncommon within urologic practice and may be difficult to diagnose and treat. We aim to highlight contemporary studies examining surgical interventions for patients with caliceal diverticula, with a focus on percutaneous intervention, and provide updated practical recommendations for the management of these patients.

RECENT FINDINGS

Studies within the last 3 years examining surgical treatment options for caliceal diverticular calculi are limited. When flexible ureteroscopy (f-URS) and percutaneous nephrolithotomy (PCNL) are examined within the same observational cohorts, PCNL is associated with improved stone-free rates (SFRs), lower requirement for re-intervention, and longer lengths of stay (LOS). Retrograde f-URS for the treatment of caliceal diverticula and diverticular calculi is associated with satisfactory safety and efficacy outcomes. There are no studies in the last 3 years that provide supporting evidence to use shock wave lithotripsy to treat caliceal diverticular calculi.

SUMMARY

Recent studies examining surgical interventions for patients with caliceal diverticula are limited to small observational studies. Heterogeneity in LOS and follow-up protocol limits comparisons between series. Despite technological advancements in f-URS, PCNL appears to be associated with more favorable and definitive outcomes. PCNL continues to be the preferred treatment strategy for patients with symptomatic caliceal diverticula when deemed technically feasible.