Analysis of Hemorrhagic Shock Following Percutaneous Nephrolithotomy Resulting from Diaphragm Injury: A Case Report.

BACKGROUND: Percutaneous nephrolithotomy (PCNL) is the first treatment for complex renal and/or ureteral calculi. This paper presents a case of hemorrhagic shock resulting from diaphragm injury due to PCNL, which has not been reported so far. CASE PRESENTATION: A 55-year-old Asian woman presented with a 2 × 2 cm calculus located in the upper calyx of the right kidney. After her uncomplicated PCNL operation, the patient's blood pressure decreased to less than 90/60 mmHg, and her hemoglobin level dropped from 128 g/L to 76 g/L. Physical examination and bedside ultrasound indicated a small amount of pleural effusion. Subsequently, a diagnostic puncture of the chest cavity was performed and revealed the presence of fresh blood. Therefore, thoracic closed drainage was conducted, and 950 mL of fresh blood was drained through a drainage tube. Intraoperatively, observation showed that the nephrostomy tube had penetrated the kidney through the diaphragm. The nephrostomy tube was subsequently removed, and the diaphragm was repaired. CONCLUSIONS: Hemorrhagic shock due to diaphragm injury is an unusual complication after PCNL. This complication should be considered if pleural effusion is present and if blood pressure progressively drops with no other obvious explanation. The recommended treatments include diagnostic thoracentesis and thoracic exploration.

Comparison of standard percutaneous nephrolithotomy and total tubeless percutaneous nephrolithotomy in the supine position.

PURPOSE: To compare the efficacy, safety and advantages of the total tubeless (TT) percutaneous nephrolithotomy (PCNL) and standard PCNL in the supine position. METHODS: This study was carried out at Izmir Tepecik Health Application and Research Center. A total of 87 patients were examined. Forty-three patients who underwent TT procedure were defined as Group 1, and 44 patients who underwent standard procedure with a nephrostomy tube were defined as Group 2. Two techniques were evaluated with demographic data and outcome parameters. Univariate regression analyses were performed in these data sets for the parameters that predicted the TT procedure. RESULTS: The demographic data of the groups and all characteristics of the stones were similar. When the results were examined, the stone-free rates detected by non-contrast computed tomography (CT) in the postoperative 1st month were similar between the groups. Complication rates and secondary intervention rates were similar. Operation and fluoroscopy times were shorter in group 1, which were not statistically significant. Postoperative hemoglobin decreased, and creatinine values were similar. In Group 1, mean postoperative visual analog scale (VAS) scores and the percentage of VAS reporting > 5 points for pain level measurement were lower and statistically significant. In the univariate analysis of the factors predicting the TT procedure, no significant results were found in any parameter. CONCLUSION: Performing TT PCNL in the supine position in selected patients reduces postoperative pain without affecting the complication rates as in prone PCNL. Our study is the first to compare TT and standard PCNL in supine position.

The effect of endoscopic renal and ureteral stone surgeries on renal blood flow in children: a prospective trial.

AIM: To assess the impact of endoscopic stone surgeries on renal perfusion and blood flow in children. MATERIALS AND METHODS: Children who underwent percutaneous nephrolithotomy (PCNL), retrograde intrarenal surgery (RIRS), ureterorenoscopy (URS), endoscopic combined intrarenal surgery (ECIRS) were included to the study. Renal Doppler ultrasonography (RDUS) was performed one day before the operation, and on the postoperative 1st day and 1st month. Peak systolic velocity (PSV) and end-diastolic velocity (EDV) were measured, and resistive index (RI) was calculated with the (PSV-EDV)/PSV formula. RDUS parameters were compared before and after surgery and between ipsilateral and contralateral kidneys. RESULTS: A total of 45 children with a median age was 8 (2-17) years were included (15 (33.3%) girls, 30 (66.7%) boys). PCNL was performed in 13 children (28.9%), RIRS 11 (24.4%), URS 12 (26.7%), and ECIRS 9 (20%). There was no significant difference in renal and segmental PSV, EDV and RI values of operated kidney in the preoperative, postoperative periods. There was no significant difference between RDUS parameters of the ipsilateral and contralateral kidneys in preoperative or postoperative periods. PSV and EDV values were significantly higher in the 1st postoperative month in the group without preoperative DJ stent than in the group with DJ stent (p = 0,031, p = 0,041, respectively). However, RI values were similar. The mean RI were below the threshold value of 0.7 in each period. CONCLUSION: RDUS parameters didn't show a significant difference in children. Endoscopic surgeries can be safely performed in pediatric stone disease.

STONE Score: A Predictor for Need of Blood Transfusion in Percutaneous Nephrolithotomy.

OBJECTIVE: To determine if the STONE score is a predictor of blood transfusion and if patient-related factors, i.e., the presence of comorbidities such as urinary tract infection and obesity, can predict blood transfusion post-percutaneous nephrolithotomy. STUDY DESIGN:  A cross-sectional descriptive study.  Place and Duration of the Study: Department of Urology, The Aga Khan University Hospital, Karachi, Pakistan, between March 2022 and 2023. METHODOLOGY: All patients admitted for percutaneous nephrolithotomy (PNCL) were included in the study. STONE score and patient related factors were assessed. Chi-square or Fisher's exact test was applied to check the association between the dependent variables (blood transfusion) and the independent variables. Logistic regression analysis was applied to compare the variables responsible for the outcome.  Results: During the study period, 150 patients underwent PCNL. After exclusion, 89 patients were included in the study. The mean STONE score was 7.87, and the total number of transfusions was 8 (8.9%). BMI (body mass index) >25kg/m2 and STONE score were found to be significant factors predicting the need for transfusion with p-values of 0.02 and 0.03, respectively. On multivariate analysis, only BMI was found to be a significant contributing factor for blood transfusion. CONCLUSION:  High BMI and STONE score are significant predictive factors for blood transfusion post-PCNL. Blood product arrangements should be restricted to obese patients. KEY WORDS: STONE score, Body mass index, Blood transfusion.

Stone centers: a national survey on surgical techniques performed in Italy.

BACKGROUND: Recurrent and complex stone disease may be considered a challenging disease. In 2018, the Calculus group of the SIU (Italian Society of Urology) set itself the goal of establishing the minimum requirements for a center that could continuously manage urolithiasis pathology, named a Stone Center. In this study we present the results of a pilot survey carried out in 2019 with the aim of drawing a map of the situation of Italian urological centers dealing with urinary stones. METHODS: A total of 260 national urology departments dealing with urolithiasis surgery were contacted for this study. A survey was issued to each of the centers to determine the number of patients treated for urinary stones and the amount of procedures performed per year: 1) extracorporeal shock wave lithotripsy ESWL; 2) ureterorenoscopy URS; 3) retrograde intrarenal surgery RIRS; 4) percutaneous nephrolithotomy PCNL. RESULTS: Out of 260 centers contacted, 188 fulfilled the survey. Outcomes were quite variable, with approximately 37% of the centers lacking a lithotripter, and 46% of those that did have it performing fewer than 100 treatments per year. In terms of endoscopic procedures, more than 80% of the centers contacted performed URS or RIRS; however, when it came to percutaneous lithotripsy, these numbers dropped significantly; 33% of the centers contacted did not perform PCNL, and of those who did, 18% had less than 5 years of experience as a center. CONCLUSIONS: Our survey shows a very heterogeneous national picture about urolithiasis treatments. Our goal is to create national paradigms to be able to define stone centers where the patient suffering from complex urinary stones can find a network of professionals with an adequate armamentarium suitable for the management of their pathology.

Ultrasound-guided renal puncture followed by endoscopically guided tract dilatation vs standard fluoroscopy-guided percutaneous nephrolithotomy for non-opaque renal stones; a randomized clinical trial.

This study was designed to evaluate the non-inferiority of ultrasound puncture followed by endoscopically guided tract dilatation compared to the standard fluoroscopy-guided PCNL. Forty patients with non-opaque kidney stones eligible for PCNL were randomly divided into two groups. The standard fluoroscopy-guided PCNL using the Amplatz dilator was performed in the XRAY group. In the SONO group, the Kidney was punctured under an ultrasound guide followed by tract dilatation using a combination of the Amplatz dilator based on the tract length and an endoscopically guided tract dilatation using a bi-prong forceps in cases of short-advancement. The primary outcome was successful access. In 90% of cases in the XRAY and 95% in the SONO group access dilatation process was performed uneventfully at the first attempt (p = 0.5). In 45% of cases in the SONO group, bi-prong forceps were used as salvage for short-advancement. In one case in the X-ray group over-advancement occurred. One month after surgery, the stone-free rate on the CT-scan was 75% for the X-ray group and 85% for the SONO group (p = 0.4). There were no significant differences in operation time, hospitalization duration, transfusion, or complication rates between the two groups. We conclude that ultrasound-guided renal puncture, followed by endoscopically guided tract dilatation can achieve a high success rate similar to X-ray-guided PCNL while avoiding the harmful effects of radiation exposure and the risk of over-advancement.

Comparison of supine-prone percutaneous nephrolithotomy methods in the treatment of kidney stones in pediatric patients: prospective randomized study.

Mini-PCNL is one of the most effective surgical methods in the treatment of kidney stones in pediatric patients. In this study, we aimed to compare PCNL in the supine-prone position in pediatric patients (especially operation time, postop complications, hospital stay and stone-free rates).We conducted our study in a randomized and prospective manner. Patients with lower pole stones larger than 1 cm, stones larger than 1.5 cm in the pelvis, upper pole, midpole or multiple locations, and patients who did not respond to ESWL or whose family that preferred mini-PCNL to be the primary treatment were included in the study. Patients with any previous kidney stone surgery, patients with coagulation disorders and patients with retrorenal colon were excluded from the study. Between 2021 and 2023, a total of 144 patients underwent PCNL. 68 of these patients had supine PCNL and 76 prone PCNL. Postoperative Clavien grade1 complication occurred in a total of 7 patients in the prone position; Clavien grade1 complication occurred in 1 patient in the supine position. The mean operation time for prone PCNL was 119.88 ± 28.32 min, and the mean operative time for supine PCNL was 98.12 ± 14.97 the mean hospitalization time in prone PCNL was 3.56 ± 1.12 days, and 3.00 ± 0.85 days in supine PCNL. In conclusion, supine PCNL is a safe and effective method in the treatment of pediatric kidney stones and postoperative complications were observed to be less; the operation time and hospital stay were shorter in supine PCNL.

Evaluation of erector spinae plane block in patients undergoing percutaneous nephrolithotomy in terms of postoperative pain reduction and patient satisfaction.

OBJECTIVES: Intravenous opioids and local anesthetic infiltrations are traditionally used to relieve postoperative pain. With developments in the field of regional anesthesia, several methods are now available for postoperative analgesia. This study aimed to investigate the efficacy of the erector spinae plane block (ESPB) in reducing both intraoperative opioid consumption and postoperative analgesic use in patients undergoing percutaneous nephrolithotomy (PCNL). METHODS: A total of 60 patients who underwent PCNL were divided into two groups: 30 patients who received ESPB (Group I) and 30 patients in the control group (Group II). Intraoperative and postoperative opioid usage were recorded for both groups. The pain levels of the patients were evaluated using visual analog scale (VAS) scores obtained at 1, 3, 6, 12, and 24 hours postoperatively. Postoperative satisfaction of the patients in both groups was also questioned and compared. RESULTS: A significant difference was detected between Group I and Group II patients in terms of intraoperative opioid require-ments (p=0.00), analgesic requirements in the first 24 hours postoperatively (p=0.00), patient satisfaction status (p=0.00), and VAS scores obtained at 0, 3, 6, and 12 hours postoperatively. No significant difference was found in VAS scores at the 24th postoperative hour. CONCLUSION: ESPB is a simple, convenient technique that can be performed under ultrasound guidance. It provides remarkable postoperative analgesia and satisfaction in patients undergoing PCNL.

Bilateral Single-session PCNL with Minimally Invasive Technique in Pediatric Nephrolithiasis.

PURPOSE: To assess outcomes of bilateral single-session percutaneous nephrolithotomy (PCNL) with minimally invasive techniques in pediatric population. MATERIALS AND METHODS: From August 2015 to July 2021, 45 children (including 12 infants) were treated with bilateral single-session PCNL, which included miniPCNL (12-16-Fr) and Microperc (4.8-Fr). Patient, stone and operation-related characteristics, stone-free rate (SFR) and complication rate (CR) were compared using ANOVA. Independent predictors were determined using multivariate linear regression. RESULTS: The mean stone burden was 3.2 cm in sum diameter for both kidneys. For bilateral kidneys, the mean operative time was 61.6min and SFR was 93.3%; CR was 53.3%, of which complications of Clavien grade 1 and 2 accounted for 46.7%. Bilateral Microperc, bilateral miniPCNL and Microperc plus miniPCNL was performed in 19, 14 and 12 children respectively. Both irrigation volume and postoperative stay were less in groups with Microperc. Both SFRs and CRs were satisfactory for the three groups. Self-limiting hematuria represented the most common complication of all cases (33.3%), especially in groups with miniPCNL. The stone burden was the only independent predictor for operative time (P < .001) and the postoperative complication (P = .008). Children with older age (P = .009), higher body mass index (P = .016) or a higher stone burden (P < .001) received larger irrigated fluid volume. Microperc was associated with less irrigated fluid volume (P = .001). Children with Clavien grade 3 complications (P = .004) spent prolonged postoperative hospital stay. CONCLUSION: With favourable SFR and acceptable CR, bilateral single-session PCNL with minimally invasive techniques might be an effective and safe procedure for pediatric nephrolithiasis.

A retrospective cohort study: evaluating the efficacy of standard versus tubeless percutaneous nephrolithotomy (PCNL) in pediatric patients up to 18 years old.

Percutaneous nephrolithotomy (PCNL) is an endourological method applied as the standard or tubeless method for kidney stone treatment. In a retrospective cohort study, 88 surgery units involving 75 children up to 18 years old with kidney stones who underwent the surgery for 8 years in Shahid Beheshti and Boo-ali hospitals in Hamadan with one of the two methods of standard or tubeless PCNL were evaluated and compared considering the success rate of operation, hemoglobin, hematocrit drop, need for medications, need for blood transfusion, duration of surgery, and the length of hospital stay. Among the 88 units studied, 47 cases were operated with the standard PCNL and 41 cases by tubeless method. In children operated by standard and tubeless PCNL, the complete success rate of operation was 87.2% and 100% (P = 0.006), the need for blood transfusion was 2.1% and 0% (P = 1.00), the need for opioids was 27.7% and 14.6% (P = 0.134), the decrease in hemoglobin was - 1.82 ± 0.94 and -1.30 ± 0.98 mg/dl (P = 0.024), the decrease in hematocrit was - 5.40 ± 2.66 and -3.52 ± 3.11 mg/dL (P = 0.003), the mean surgery duration was 109.30 ± 53.27 and 101.46 ± 31.92 min (P = 0.414), the duration of postoperative hospitalization was 3.38 ± 1.76 and 2.46 ± 1.27 days (P = 0.007), and the frequency of fever was 23.4% and 7.3% (P = 0.04), respectively. The success rate of kidney stone surgery in children with the tubeless PCNL is higher than the standard method, and its complications are lower.

Prone vs supine percutaneous nephrolithotomy: does position affect renal pelvic pressures?

The purpose of this study was to measure and compare renal pelvic pressure (RPP) between prone and supine percutaneous nephrolithotomy (PCNL) in a benchtop model. Six identical silicone kidney models were placed into anatomically correct prone or supine torsos constructed from patient CT scans in the corresponding positions. A 30-Fr renal access sheath was placed in either the upper, middle, or lower pole calyx for both prone and supine positions. Two 9-mm BegoStones were placed in the respective calyx and RPPs were measured at baseline, irrigating with a rigid nephroscope, and irrigating with a flexible nephroscope. Five trials were conducted for each access in both prone and supine positions. The average baseline RPP in the prone position was significantly higher than the supine position (9.1 vs 2.7 mmHg; p < 0.001). Similarly, the average RPP in prone was significantly higher than supine when using both the rigid and flexible nephroscopes. When comparing RPPs for upper, middle, and lower pole access sites, there was no significant difference in pressures in either prone or supine positions (p > 0.05 for all). Overall, when combining all pressures at baseline and with irrigation, with all access sites and types of scopes, the mean RPP was significantly higher in the prone position compared to the supine position (14.0 vs 3.2 mmHg; p < 0.001). RPPs were significantly higher in the prone position compared to the supine position in all conditions tested. These differences in RPPs between prone and supine PCNL could in part explain the different clinical outcomes, including postoperative fever and stone-free rates.

Comparison of safety and efficacy of tubeless vs. conventional mini percutaneous nephrolithotomy in patients with Escherichia coli bacteriuria.

To evaluate the safety and efficacy of tubeless percutaneous nephrolithotomy (PCNL) in patients with Escherichia coli (E. coli) bacteriuria. We conducted a retrospective review of 84 patients with E. coli bacteriuria who underwent PCNL. Patients were divided into two groups according to whether a nephrostomy tube is placed at the end of the procedure. Preoperative clinical data, surgical outcomes, and postoperative complications were compared. Then, regression analysis of factors predicting success rate of PCNL in patients with E. coli bacteriuria was performed. After PCNL, residual fragments ≤ 4 mm were considered as success. At baseline, the two groups were similar with regard to age, gender, BMI, underlying disease, hydronephrosis, stone characteristics, and urinalysis. Postoperative fever occurred in 1 patient (3.8%) in the tubeless PCNL group, and in 5 patients (8.6%) in the conventional PCNL group (p > 0.05). There were no significant differences in terms of successful rate, decrease in hemoglobin, pain scores, blood transfusion, and hospitalization expenses. However, the tubeless PCNL group had significantly shorter operative time (60 vs. 70 min, p = 0.033), indwelling time of catheter (2 vs. 4 days, p < 0.001), and hospital stays (3 vs. 5 days, p < 0.001) than the conventional PCNL group. In the analysis of factors predicting success, the stone diameter, stone burden, and operative time were associated with success rate of PCNL. It is safe and effective to perform tubeless PCNL in patients with E. coli bacteriuria. Compared to conventional PCNL, tubeless PCNL accelerates patient recovery and shortens hospital stays.

Comparative analysis of combined spinal-epidural anesthesia and general anesthesia in percutaneous nephrolithotomy: a prospective study on surgical team and operating room personnel satisfaction.

OBJECTIVE: We aimed to investigate the efficacy and complications of combined spinalepidural anesthesia and general anesthesia in percutaneous stone surgery prospectively. MATERIALS AND METHODS: The study prospectively included patients who underwent percutaneous nephrolithotomy with general anesthesia (Group.1) or combined spinal-epidural anesthesia (Group.2) at the Department of Urology, Training and Research Hospital, Karabuk University. between December 2018 and December 2019. The effect of the anesthesia technique on the comfort and satisfaction of the operating room personnel, surgeon and anesthesia team were prospectively evaluated and recorded. RESULTS: During the postoperative period, the spinal anesthesia group had a significantly lower visual analog score than the general anesthesia group. No patient in either group required narcotic analgesics during the postoperative period. In terms of overall satisfaction scores, the surgeon performing the surgical procedure had a significantly higher satisfaction score in the general anesthesia group than in the CSEA group. The score was considered good in the general anesthesia group and moderate in the CSEA group. Personnel satisfaction was higher in the patient group that underwent CSEA. In the general anesthesia group, the score was considered to be average. In the CSEA group, the satisfaction score was considered good, with a statistically significant difference (p < 0.05). The anesthesia team's satisfaction score was moderate, with no significant difference between the CSEA and general anesthesia groups (p > 0.05). CONCLUSION: PCNL under CSEA can be performed safely in certain individuals. Different anesthetic techniques may have varied levels of satisfaction among the surgical team.

Percutaneous nephrolithotomy or flexible ureteral lithotripsy, which one is better for patients with upper ureteral calculi of 1.5-2.0 cm in diameter.

PURPOSE: First research to evaluate the clinical efficacy and safety of flexible ureteral lithotripsy (FURSL) and percutaneous nephrolithotomy (PCNL) in the treatment of the upper ureteral stone is between 1.5 cm and 2.0 cm in diameter since there is no consensus with such ureteral stone yet. METHODS: From December 2018 to October 2022, 104 patients with calculi in the upper ureter received percutaneous nephrolithotomy (PCNL)or flexible ureteroscopic lithotripsy (FURSL) in our institution. The clinical data of the patients in the two groups were retrospectively searched. Stone removal rate, operation time, blood loss, postoperative pain score, postoperative inflammatory factor, postoperative complication rates and ureteral obstruction three months after the operation were compared between the two groups. RESULTS: A total of 104 patients were included in the study. The stone clearance rate and the secondary surgery rate were 88.89% and 7.41% in the FURSL group, the figures were 97.96% and 2.0% in the PCNL group (p = 0.067, 0.497). Regarding ureteral obstruction three months after the operation, there were 2 patients in FURSL group and 0 patients in PCNL group(p = 0.497).Compared to patients in FURSL group, patients in the PCNL group had shorter operation time(PCNL 71.81 ± 18.94 min vs. FURSL 86.80 ± 22.49 min, p = 0.0004), fewer complications(PCNL 20.37% vs. FURSL 6.12%), and lower postoperative inflammatory factor(p = 0.0004), yet they got more hemoglobin drop (PCNL 13.14 ± 9.81 g/L vs. FURSL 4.77 ± 3.55 g/L, p < 0.0001), higher postoperative pain scores(p = 0.0017) in the first three postoperative days and longer hospital stay (PCNL 4.96 ± 1.21 days vs. FURSL 3.60 ± 0.83 days). CONCLUSION: Both FURSL and PCNL were effective methods for treating upper ureteral stones of 1.5-2.0 cm in diameter given the extremely high stone clearance rate and a very low secondary surgery rate, as long as rare ureteral obstruction in medium-long term observation. Additionally, FURSL can effectively reduce surgical bleeding, postoperative pain, and hospital stay, while PCNL can decrease operation time, the risk of infection, and complications. Therefore, doctors could select suitable surgical treatment for those patients depending on their different clinical situations based on these findings.

[Colon injury during percutaneous nephrolithotomy (clinical case, literature review)].

Urolithiasis occupies one of the leading places in terms of the frequency of requests for urgent urological care and emergency hospitalization in specialized departments. Percutaneous surgery for urolithiasis, like any of the surgical methods, is associated with a number of specific and non-specific complications. Of course, the frequency of occurrence is dominated by hemorrhagic and inflammatory complications. But damage to the colon is quite rare and amounts to 0.3-0.4%. Focusing on the literature data, it is possible to identify risk factors for colon damage and clinical manifestations of this complication. Given the small clinical experience, both in the world and in the domestic literature, there is no recommendatory base for the management of patients with colon damage during percutaneous interventions. Publications available for analysis indicate the possibility of both an operative approach with the removal of a colostomy and conservative management of patients with such complications. The article presents a clinical observation of successful conservative management of a patient with damage to the descending colon during percutaneous nephrolithotomy. An assessment of risk factors for colon damage in this patient was given. Imaging methods are presented that confirm the presence of this complication and the resulting recovery during the follow-up examination.

Flank versus prone position in percutaneous nephrolithotomy: a meta-analysis of randomized controlled studies.

The objective of this study is to assess the safety and efficacy of the flank position in percutaneous nephrolithotomy (PCNL). We searched PubMed, Embase, SCOPUS, the Cochrane database libraries, and the Chinese Biomedical Literature Database, and randomized controlled trials (RCTs) assessing PCNL in flank position are included in this meta-analysis. The related trials met the inclusion criteria were analyzed using RevMan 5.4. Seven randomized controlled trials were included, involving a total of 587 patients. We found that there was a lower decrease in hemoglobin levels in the flank position group compared to prone-position group (mean difference [MD] = - 0.15, 95% confidence interval (CI) - 0.22 to - 0.08, P < 0.00001). Moreover, our meta-analysis demonstrated no significant differences between groups regarding stone-free rate (relative risk [RR] = 1.00, 95% CI 0.93 to 1.06, P = 0.92), operative time(MD = 0.76, 95% CI - 5.31 to 6.83, P < 0.00001), hospital stay (MD = 0.03, 95% CI - 0.32 to 0.32, P < 0.00001), and complications Clavien grade I (RR = 1.01, 95% CI 0.98 to 1.05, P = 0.54), Clavien grade II (RR = 1, 95% CI 0.97 to 1.02, P = 0.78), and Clavien grade III (RR = 1, 95% CI 0.98 to 1.03, P = 0.77). The use of flank position for PCNL is associated with reduced hemoglobin change without an increase in complications. This positioning technique can be considered safe for patients with nephrolithiasis and may be particularly suitable for high-risk individuals such as those who are obese or have decreased cardiopulmonary function. However, further randomized trials are needed to confirm these findings.

Radiation exposure of patients during endourological procedures.

PURPOSE: Considering the existing gaps in the literature regarding patient radiation dose (RD) and its associated risks, a systematic review of the literature on RD was conducted, focusing on percutaneous nephrolithotomy (PCNL), extracorporeal shock wave lithotripsy (SWL), and ureteroscopy (URS). METHODS: Two authors conducted a literature search on PubMed, Web of Science, and Google Scholar to identify studies on RD during endourological procedures. Two thousand two hundred sixty-six articles were screened. Sixty-five publications met the inclusion criteria using the PRISMA standards. RESULTS: RD was generally highest for PCNL, reaching levels up to 33 mSv, 28,700 mGycm2, and 430.8 mGy. This was followed by SWL, with RD reaching up to 7.32 mSv, 13,082 mGycm2, and 142 mGy. URS demonstrated lower RD, reaching up to 6.07 mSv, 8920 mGycm2, and 46.99 mGy. Surgeon experience and case load were inversely associated with RD. Strategies such as optimizing fluoroscopy settings, implementing ultrasound (US), and following the ALARA (As Low As Reasonably Achievable) principle minimized RD. CONCLUSIONS: This is the first systematic review analyzing RD, which was generally highest during PCNL, followed by SWL and URS. There is no specific RD limit for these procedures. Implementation of strategies such as optimizing fluoroscopy settings, utilizing US, and adhering to the ALARA principle proved effective in reducing RD. However, further research is needed to explore the factors influencing RD, assess their impact on patient outcomes, and establish procedure-specific reference levels for RD.

Developing an Ex Vivo Pig Model for Teaching Ultrasound and Fluoroscopy-Guided Percutaneous Renal Access.

Introduction: Establishing percutaneous renal access is the key initial step to percutaneous nephrolithotomy; however, learning the technique during surgery for trainees is complicated by the number of approaches used to gain access, limited completion time during a breath hold. and attempt to minimize the number of passes through a kidney. There are many training models for percutaneous access commercially available all with their respective limitations. Our objective was to develop a low-cost, high-fidelity percutaneous access training model that addresses existing limitations and can be used with both ultrasound and fluoroscopy guidance. Methods: After a formal ethics exemption was attained, pig cadavers were harvested for flank, kidneys, and ureters. These were incorporated into a composite porcine tissue mould, created within a gelatin matrix. In the initial assessment, establishing percutaneous access under both ultrasound and fluoroscopy guidance was tested to refine usability. Once acceptable, its use during a training course was evaluated to assess impressions for use with ultrasound. Results: We were able to create a $45USD biodegradable model, which can facilitate percutaneous access using: fluoroscopy with intrarenal contrast; fluoroscopy with endoscopic guidance; and fluoro-less that is, ultrasound only. A cohort of 12 Canadian Postgraduate Year-3 residents who used the model for ultrasound access agreed that the model simulated a comparable tactile experience (58.33%) and anatomy (75%) to humans. Furthermore, majority of the residents agreed that model was easy to use with ultrasound guidance (91.67%), was a beneficial experience for their learning and future practice (83.33%) and if available would use to complement their intraoperative training (83.33%). Conclusion: We were able to develop a low-cost, preliminarily tested ex vivo pig model for percutaneous access compatible with multiple imaging modalities. We will continue refining our model and seek to understand its benefits when teaching percutaneous access to varying levels of learners.