Minimally invasive percutaneous nephrolithotomy vs standard PCNL for management of renal stones in the flank-free modified supine position: single-center experience

Vacuum-Assisted vs Conventional Minimally Invasive Percutaneous Nephrolithotomy for the Treatment of Two-to-Four-Centimeter Stones: A Multicenter Prospective and Randomized Trial

Introduction: Percutaneous nephrolithotomy (PCNL) is the recommended treatment for 2-4-cm renal stones. Minimally invasive PCNL (MPCNL) with ≤22F sheath was frequently used instead of standard PCNL. MPCNL uses pressurized irrigation to flush out stone fragments through a conventional nephrostomy sheath (cNS), which may result in higher intrarenal pressure (IRP) and longer operating time. The novel vacuum-assisted nephrostomy sheath (vaNS) was developed to mitigate higher IRP and to facilitate stone removal. It might improve the performance of MPCNL. This prospective and randomized trial compares these two sheaths. Materials and Methods: In total, 120 patients with 2-4-cm renal stones were accrued in six tertiary medical centers with equal numbers in 2021. In total, 120 patients underwent mPCNL, 60 using 18F cNS and 60 using 18F vaNS, in a prospective and randomized assignment. The primary outcome measurement is decrease in IRP. The secondary outcome is efficacy in stone retrieval. Results: The IRP was lower with vaNS than with cNS: mean IRP during lithotripsy was 12.0 ± 2.7 mm Hg with vaNS vs 20.4 ± 6.0 mm Hg with cNS, p = 0.000. IRP duration ≥30 mm Hg was shorter with vaNS than with cNS (6.7 ± 7.4 seconds vs 113.4 ± 222.7 seconds, p = 0.001). vaNS has shorter stone removal time (26.9 ± 14.3 minutes vs 35.7 ± 11.8 minutes, p = 0.000). Stone extraction rate was higher (166.4 ± 88.1 mm3/min vs 90.4 ± 31.7 mm3/min, p = 0.000). Stone grasper usage was less (1.4 ± 2.6 vs 11.9 ± 9.7, p = 0.000). vaNS maintained the safety profile. Blood loss, creatinine changes, perioperative complications, and hospital stays were the same in both groups, all p > 0.05. Conclusion: MPCNL for stones 2-4 cm using vaNS has shorter stone removal time, higher stone extraction rate, and less use of stone extractor. vaNS is superior to cNS at reducing IRP and is associated with improved stone free rates at 3 days but not at 30 days postoperatively. The trial was registered with Chinese Clinical Trial Registry (ClinicalTrials.gov, NCT ChiCTR2000039681).

Comparison Between Mini-Percutaneous Nephrolithotomy and Standard Percutaneous Nephrolithotomy in Management of Large Renal Stones: A Randomized, Controlled Clinical Trial

Objectives: The aim of this study was to compare mini-percutaneous nephrolithotomy (PNL) and standard PNL in management of renal stones (20-40 mm) with regard to the operative time, fluoroscopy time, blood loss, stone-free rate, and postoperative complications. Subjects and Methods: This prospective, randomized comparative study was carried out on 93 patients divided into two groups: Group A included 44 patients who underwent standard PNL, whereas Group B included 49 patients who underwent mini-PNL. Results: Standard PNL showed shorter operative time, yet longer hospitalization and nephrostomy and catheterization time. The mean drop in hemoglobin level was significantly lower in the mini-PNL group. In the 1st postoperative week, the stone-free rate was higher in the standard PNL group, but this was statistically insignificant. However, 4 weeks postoperatively, the stone-free rate was significantly higher in Group A. Postoperative pain and the need for postoperative analgesia were significantly higher in standard PNL patients. Conclusions: Standard PNL achieved a higher stone-free rate and shorter operative time, while mini-PNL had the advantage of shorter hospitalization time and lower incidence of pain and postoperative complications.

Super-stiff guidewire or loach guidewire during percutaneous nephrolithotomy?

Objectives

The objectives of this work are to compare the outcomes between loach guidewire and super-stiff guidewire during percutaneous nephrolithotomy (PCNL) and find potential indications of different guidewires.

Patients and methods

We retrospectively reviewed our institutional PCNL database from 2017 to 2021. Patients who underwent PCNL guided by loach guidewire were assigned to group A (489 patients); patients who received super-stiff guidewire were assigned to group B (269 patients). Preoperative demographic data, intraoperative parameters, and postoperative complications were compared. The conditions and reasons of failed placement of guidewire needed readjustment were evaluated as well.

Results

Preoperative demographic data and most intraoperative parameters were not statistically different between the groups. Postoperative Clavien-Dindo complications were also comparable, with low rate of complications. However, failed placement of guidewire more occurred in group A (8.2% vs. 4.0%, respectively, p = 0.03). Compared with the super-stiff guidewire, the loach guidewire was easier pass/slip into any place either it be perinephric or blood vessels. In most failed group A cases and all failed group B cases, the guidewire was placed in the perirenal fat. Six patients (15%) in group A, the guidewires entered into vessels.

Conclusions

Our results support that the faulty placement of loach guidewire is significantly more common compared with super-stiff guidewire. Double confirmation is needed to prevent a major complication out of wrong dilatation whenever there is doubt about the wrong location of the guidewire.

Efficacy and safety of various endosurgical procedures for management of large renal stone: a systemic review and network meta-analysis of randomised control trials

Urolithiasis is the most common benign urological health condition. It has contributed sizeable burden of morbidity, disability, and medical health expenditure worldwide. There is limited high level of evidence on the efficacy and safety of treatment options of large renal stones. This network meta-analysis has examined the effectiveness and safety of various large renal stone management strategies. Systematic review and network meta-analysis (NMA) study design was employed to summarize comparative randomized controlled trials on humans with a diagnosis of renal stone larger than or equal to 2 cm in size. Our searching strategy was based on the Population, Interventions, Comparison, Outcomes, and Study (PICOS) approach. Medline via PubMed, Embase, Google scholar, SCOPUS, Science Direct, Cochrane library, Web of Science, and ClinicalTrials.gov were searched from inception to March 2023 to find eligible articles. Data extraction, screening, selection and risk of bias assessment were conducted by two independent reviewers. We found ten randomised control trials which consists 2917 patients, nine of them were labeled as low risk and one article was high risk. This network meta-analysis found that SFR was 86% (95% CI 84-88%) for Mini-PCNL, 86% (95% CI 84-88%) for standard PCNL, 79% (95% CI:73-86%) for RIRS, and 67% (95%CI:49-81 for staged URS for management of large renal stone. Overall complication rate was 32% (95% CI 27-38%) for standard PCNL, 16% (95% CI 12-21%) for Mini-PCNL, and 11% (95% CI 7-16%) for RIRS. Mini-PCNL (RR = 1.14 (95% CI 1.01-1.27) and PCNL (RR = 1.13 (95% CI 1.01-1.27)) were statistically associated with a higher SFR compared to RIRS. The pooled mean hospital stays were 1.56 days (95% CI 0.93-2.19) for RIRS, 2.96 days (95% CI 1.78-4.14) for Mini-PCNL, 3.9 days (95% CI 2.9-4.83) for standard PCNL, and 3.66 (95% CI 1.13-6.2) for staged URS. Mini-PCNL and standard PCNL were the most effective treatment options with significant morbidity and length of hospital stay, while RIRS was the safest management option with acceptable SFR, low morbidity, and short hospital stay.

Comparison of postoperative outcomes of mini percutaneous nephrolithotomy and standard percutaneous nephrolithotomy: a meta-analysis

Our study was aimed to evaluate the postoperative outcomes of Mini Percutaneous Nephrolithotomy (Mini-PCNL) and Standard Percutaneous Nephrolithotomy (Standard-PCNL) to determine the optimum option for patients with renal calculi. For publications published between January 2010 and April 2021, a comprehensive search of the PubMed, Cochrane Library, Web of Science, and EMBASE databases was done. The literatures were chosen based on the criteria for inclusion and exclusion. After the data were retrieved and the quality was assessed, the meta-analysis was performed using Review Manager Software (RevMan 5.4.1, Cochrane Collaboration, Oxford, UK). We selected 20 trials with a total of 4953 people out of 322 studies. There were 2567 patients treated with Mini-PCNL and 2386 patients treated with Standard-PCNL. Meta-analysis results showed no difference in stone-free rates (SFR, P = 0.93), fever (P = 0.83), and postoperative pain (VAS score) (P = 0.21) between Mini-PCNL and Standard-PCNL. Patients in the Mini-PCNL group experienced shorter hospital stay (P < 0.0001), less hemoglobin drop (P < 0.00001), less blood transfusion (P < 0.00001), higher postoperative tubeless (P = 0.0002), and fewer complications including bleeding (P = 0.01), perforation (P = 0.03), and leakage (P = 0.01). Compared with Standard-PCNL, operative time was longer in the Mini-PCNL group (P = 0.0005). Mini-PCNL had a shorter hospital stay, less hemoglobin drop, less blood transfusion, greater postoperative tubeless, fewer complications, and a longer operational time when compared to Standard-PCNL. SFR, fever, and postoperative pain were similar in both of them. Mini-PCNL may be a superior option for patients with proper size renal calculi.

Mini Versus Standard Percutaneous Nephrolithotomy for the Management of Renal Stone Disease: Systematic Review and Meta-analysis of Randomized Controlled Trials

CONTEXT

Mini percutaneous nephrolithotomy (mPNL) involves the creation of a smaller access tract compared with standard PNL (sPNL). Smaller tract sizes could lead to decreased blood loss, pain, and need for blood transfusion. Previous studies on this topic have reported variable findings and were of poor quality.

OBJECTIVE

To compare the safety and efficacy of mPNL with those of sPNL for the management of patients with renal stone disease by conducting a systematic review and meta-analysis.

EVIDENCE ACQUISITION

Systematic literature search was performed to identify relevant randomized controlled trials (RCTs) for the review. The primary outcomes for the study were stone-free rate (SFR) and blood transfusion rate. The secondary outcomes were complication rates, fever, fall in hemoglobin, operative time, length of stay (LOS), need for auxiliary procedure, and visual analog scale (VAS) score at 24 h. We followed Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines, and the study protocol was registered with PROSPERO in priori (CRD42021252444).

EVIDENCE SYNTHESIS

In this review, 16 RCTs with 3961 patients were included. SFR was comparable between the two groups (risk ratio [RR] 1.01 [0.99, 1.04], p = 0.30), whereas the need for transfusion was lower with mPNL (RR 0.54 [0.37, 0.78], p = 0.001). Fall in hemoglobin (mean difference [MD] -0.67 [-0.93, -0.41], p = 0.000) and LOS (MD -0.59 [-0.81, -0.37], p = 0.000) were shorter with mPNL. Operative time was significantly shorter with sPNL (MD 8.28 [3.96, 12.59], p = 0.000). Complications were lower with mPNL (RR 0.89 [0.79, 0.97], p = 0.01). The need for auxiliary procedures (RR 0.77 [0.58, 1.03], p = 0.08) and VAS at 24 h (MD -0.79 [-1.63, 0.05], p = 0.06) were similar in the two groups.

CONCLUSIONS

Mini PNL has similar efficacy to sPNL in terms of SFRs. However, mPNL has a superior safety profile with fewer overall complications and a reduced need for blood transfusion.

PATIENT SUMMARY

In this study, we conducted a meta-analysis comparing mini and standard percutaneous nephrolithotomy (PNL) for the management of patients with renal stone disease. We showed that mini and standard PNL are associated with similar stone-free rates. Overall complications and the need for blood transfusion were lower with mini PNL.

Comparison between standard, mini and ultra-mini percutaneous nephrolithotomy for single renal stones: a prospective study

PURPOSE

Based on the current trend of miniaturization of instruments used in percutaneous nephrolithotomy (PCNL), it is necessary to compare different PCNL modalities regarding their access sheath size used. Thus, the safety and efficacy among standard, mini and ultra-mini PCNL (s-PCNL, m-PCNL, um-PCNL) were compared.

METHODS

We performed a prospective, non-randomized trial between January 2018 and July 2020. Patients with stones classified as Guy's stone score grade I were included. The set-up for s-PCNL and m-PCNL included a 30 Fr and 22 Fr percutaneous tract, respectively. In both set-ups, an ultrasonic/ballistic lithotripter was utilized. In the case of um-PCNL, a 12 Fr percutaneous tract was established. A high-power laser was used for lithotripsy. Hemoglobin drop, complication rate, length of hospital stay (LOS), stone-free rate (SFR) and operation time were evaluated.

RESULTS

A total of 84 patients, 28 patients per method, were evaluated. Hemoglobin drop was higher in the s-PCNL group when compared to m-PCNL (p = 0.008) and um-PCNL groups (p < 0.001), while um-PCNL group had the slightest hemoglobin drop. LOS was similar between s-PCNL group and m-PCNL group, but um-PCNL group required shorter hospital stay than the other two modalities (p < 0.001). The complication and transfusion rates as well as SFR did not differ between groups. Operation time in the um-PCNL set-up was longer compared to s-PCNL (p < 0.001) and m-PCNL (p = 0.011), whereas s-PCNL and m-PCNL did not differ significantly.

CONCLUSION

m-PCNL showed less hemoglobin drop, but similar operation time and SFR when compared to s-PCNL. um-PCNL showed even less hemoglobin drop, but the operation time was longer compared to the two other modalities.

Could retrograde intrarenal surgery be a safe and effective alternative to mini-percutaneous nephrolithotomy ın the management of relatively large (20-30 mm) stones? A critical evaluation

PURPOSE

To compare the outcomes of mini-percutaneous nephrolithotomy (mPCNL) and retrograde intrarenal surgery (RIRS) in patients with renal stones sizing 2-3 cm.

METHODS

A total of 566 patients from 6 institutions who underwent mPCNL (n = 440) and RIRS (n = 126) procedures were enrolled in our study. The retrospective patient cohort was reviewed and compared. Binary logistic regression analysis was performed to determine factors predicting success in the RIRS group.

RESULTS

The stone-free rates were 91.1 and 77% for the mPCNL and RIRS groups, respectively (p < 0.001). The auxiliary procedure rates were 4.5 and 39.7% in the mPCNL and RIRS groups, respectively (p < 0.001). Mean values of hemoglobin decrease, fluoroscopy time, and hospitalization time were significantly higher in the mPCNL group (p < 0.001). While the Clavien grade 1-2 complication rates were 10.9 and 34.1% (p < 0.001) in two groups, these values were 2.7 and 1.6% (p = 0.539), respectively, for Clavien grade 3-4 complication rates. Although three patients in the mPCNL group received blood transfusions, none of the patients in the RIRS groups were transfused. The stone location and stone density parameters were found to be the independent predictive factors for RIRS success.

CONCLUSIONS

mPCNL provided a higher stone-free rate, less need for the auxiliary procedure, and lower complication rates compared to RIRS in patients with 2-3 cm stones. Blood loss, radiation exposure, and a hospital stay of mPCNL can be significantly reduced with the RIRS technique in selected patients.

Outcomes of Mini-Percutaneous Nephrolithotomy in Children and Adolescents: A 10-Year Single-Centre Experience From Kuwait

The current study retrospectively reviewed data for all children and adolescents who underwent mini-percutaneous nephrolithotomy (PCNL) at Ibn Sina Hospital and Sabah Al Ahmad Urology Centre in Kuwait over 10 years. Accordingly, the 40 patients underwent mini-PCNL. Among them, 21 patients (52.5%) had varying degrees of hydronephrosis, with mild to moderate severity accounting for nearly half of them, whereas six (15%) had multiple stones. The median operative time was 54.5 (43.3-64) minutes. Moreover, 11 patients needed flexible ureteroscopy (URS) and double-J (DJ) ureteric stent, and one patient required DJ ureteric stent only. None of the cases developed intraoperative bleeding. The median hospital stay of the included patients was three (2.3-4) days. Residual stone was observed in 11 patients (27.5%), with a median size of 3 (2 to 7) mm. The incidence of postoperative complications was 27.5% (n = 11 patients), with three patients experiencing postoperative bleeding (7.5%) and eight patients developing a fever (20%). All patients had mild postoperative pain. However, no leakage, sepsis, or pelvic injury occurred. None of the patients required revision. In conclusion, mini-PCNL was a safe and effective procedure in children and adolescents with renal stones.

Robot-Assisted Mini-Endoscopic Combined Intrarenal Surgery for Complex and Multiple Calculi: What Are the Real Advantages?

Background: To determine the stone-free rates (SFR) with robot-assisted mini-endoscopic combined intrarenal surgery (mini-ECIRS) and evaluate the impact of intraoperative assessment of stone-free status compared to postoperative non-contrast computed tomography (NCCT) scan findings. Methods: A total of 42 consecutive patients (44 renal units) diagnosed with complex/multiple renal stones were enrolled and reviewed in a retrospective manner. While retrograde access with the flexible scope was performed by using Avicenna Roboflex, mini-percutaneous nephrolithotomy was performed through a 16.5F sheath. Demographic, clinical characteristics of the cases along with perioperative complications were recorded, analyzed, and compared to the reported data in the literature. Results: Forty-two renal units (95.5%) were endoscopically confirmed to be stone-free at the end of the procedure, of which all were confirmed to be stone-free in postoperative NCCT examination. Complications were observed in 3 of the 42 (7.1%) patients, which were classified as Clavien grade I. The mean operation and fluoroscopy time were 103.7 ± 20.6 minutes and 71 ± 13.7 seconds, respectively. Conclusion: Our results demonstrate that robot-assisted mini-ECIRS could reveal high SFR in complex and multiple stones. In addition, endoscopic flexible ureteroscopic evaluation of the collecting system at the end of the procedure could let the surgeon predict stone-free status more reliably and successfully.

Infectious complications of endourological treatment of kidney stones: A meta-analysis of randomized clinical trials

OBJECTIVE

Endourological treatment is associated with a risk of postoperative febrile urinary tract infections and sepsis. The aim of this study was to review the reported rate of infectious complications in relation to the type and modality of the endourologic procedure.

METHODS

This systematic review was conducted in accordance with the PRISMA guidelines. Two electronic databases (PubMed and EMBASE) were searched. Out of 243 articles retrieved we included 49 studies after full-text evaluation.

RESULTS

Random-effects meta-analysis demonstrated that retrograde intrarenal surgery (RIRS) and percutaneous nephrolithotomy (PCNL) were associated with not significantly different odds of getting fever (OR = 1.54, 95% CI: 0.99 to 2.39; p = 0.06) or sepsis (OR = 1.52, 95% CI: 0.37 to 6.20, p = 0.56). The odds of getting fever were not significantly different for mini PCNL compared to standard PCNL (OR = 1.11, 95% CI: 0.85 to 1.44; p = 0.45) and for tubeless PCNL compared to standard PCNL (OR = 1.34 95% CI: 0.61 to 2.91, p = 0.47). However, the odds for fever after PCNL with suctioning sheath were lower than the corresponding odds for standard PCNL (OR = 0.37, 95% CI: 0.20 to 0.70, p = 0.002). The odds of getting fever after PCNL with perioperative prophylaxis were not different from the corresponding odds after PCNL with perioperative prophylaxis plus a short oral antibiotic course (before or after the procedure) (OR = 1.31, 95% CI: 0.71 to 2.39, p = 0.38).

CONCLUSIONS

The type of endourological procedure does not appear to be decisive in the onset of infectious complications, although the prevention of high intrarenal pressure during the procedure could be crucial in defining the risk of infectious complications.   on behalf of U-merge Ltd. (Urology for emerging countries), London-Athens-Dubai.

Mini percutaneous nephrolithotomy versus standard percutaneous nephrolithotomy for the management of renal stones over 2 cm: a systematic review and meta-analysis of randomized controlled trials

INTRODUCTION

Standard percutaneous nephrolithotomy (sPCNL) is recommended for renal stones over 2cm. Mini percutaneous nephrolithotomy (mPCNL) has also emerged as a promising technique in this setting. We performed a systematic review and meta-analysis of randomized controlled trials (RCTs) comparing the safety and efficacy of sPCNL to mPCNL for the management of renal stones over 2cm.

EVIDENCE ACQUISITION

We systematically searched PubMed, Cochrane Library and Scopus databases until April 2021 and sources of grey literature for relevant RCTs. We performed a meta-analysis of odds ratios (ORs) to compare bleeding or other complications and stone-free rate (SFR) between sPCNL and mPCNL. Similarly, we undertook a metaanalysis of weighted mean differences for the mean operative and hospitalization time between the two techniques (PROSPERO: CRD42021241860).

EVIDENCE SYNTHESIS

Pooled data from 8 RCTs (2535 patients) were available for analysis. sPCNL was associated with a higher hemoglobin drop (0.59g/dl, 95%CI: 0.4-0.77, I2=93%), higher likelihood of postoperative blood transfusion (OR: 2.58, 95%CI: 1.03-6.45, I2=30%) and longer hospital stay (0.75 days, 95%CI: 0.45-1.05, I2=73%) compared to mPCNL. No significant differences were demonstrated in SFR (OR: 0.92, 95%CI: 0.74-1.16, I2=0%) and mean operative time (4.05 minutes, 95%CI: -9.45-1.37, I2=91%) after sPCNL versus mPCNL. Similarly, no significant differences were observed for postoperative fever, pain and Clavien-Dindo complications.

CONCLUSIONS

mPCNL represents a safe and effective technique and may be also recommended as a first-line treatment modality for well-selected patients with renal stones over 2cm. Still, further high-quality RCTs on the field are mandatory, since the overall level of evidence is low.

Mini Percutaneous Kidney Stone Removal: Applicable Technologies

Percutaneous nephrolithotomy (PCNL) remains the treatment of choice for large and complex renal stones. The technological advances over the past several decades gave birth to different varieties of minimally invasive PCNLs, including the mini-PCNL, ultra-mini PCNL, super mini-PCNL, and micro-PCNL, with indications being extended to stones even larger than 20 mm. This article provides an update of all these available techniques of miniaturized PCNL along with its anatomic and physiologic impact. This should assist urologists in providing a personalized approach to the patient based on various patient- and stone-related factors to provide the best of all available technology for treatment.

A retrospective analysis on the effect of single-channel minimally invasive percutaneous nephrolithotomy combined with retrograde flexible ureteroscopy using the completely lateral decubitus and semi-lithotomy positions to treat complex kidney stones

Background

Some types of complex kidney stones cannot be broken down and removed through single-channel percutaneous nephroscope or retrograde flexible ureteroscope. In order to be removed, these types of stones require multiple combined methods to be performed. The aim of this study was to retrospectively evaluate the clinical effect of single-channel minimally invasive percutaneous nephrolithotomy (mPCNL) combined with retrograde flexible ureteroscopy using the completely lateral decubitus and semi-lithotomy positions for treating complex renal calculi.

Methods

We selected 117 patients with complex renal calculi who were admitted to Peking University Shougang Hospital and Weifang People’s Hospital from January 1, 2017, to January 31, 2021. All patients were treated with single-channel mPCNL combined with retrograde flexible ureteroscopy in the completely lateral decubitus and semi-lithotomy positions. During the operation, the patients were placed in a completely lateral decubitus position, or their lower limbs were placed in a semi-lithotomy position for a single attempt only.

Results

An 18-Fr percutaneous channel was successfully established in all patients. The mean operation time was 112±37 minutes, and the average blood loss was 71±31 mL. A 14-Fr renal fistula was maintained for 7 days, a urethral catheter for 2–3 days, and a ureteral stent tube for 2 weeks after each surgery. According to the results of computed tomography (CT) scans performed 3–5 days after the operation, the total lithotripsy success rate reached 100%, with a first-stage lithotripsy rate of 98.29%. Two patients were found to each have 1 residual stone, with a diameter of 4 mm, left in kidney by CT, which then was to be removed under local anesthesia. The average postoperative hospitalized time was 7±2 days, and no severe complications occurred perioperatively.

Conclusions

Single-channel mPCNL combined with retrograde flexible ureteroscopy in the completely lateral decubitus and semi-lithotomy positions is a safe, feasible, and highly effective method of treating complex renal calculi, which is of benefit to save operation time and facilitate operation process, because patient’s position could not need to be changed repeatedly during the surgery.

Comparison of mini percutaneous nephrolithotomy and standard percutaneous nephrolithotomy for renal stones >2cm: a systematic review and meta-analysis

BACKGROUND

The purpose is to compare the efficacy and safety of mini percutaneous nephrolithotomy (mini-PCNL) versus standard percutaneous nephrolithotomy (standard-PCNL) in patients with renal stones >2cm.

MATERIALS AND METHODS

A systematic literature search was conducted in PubMed, Web of Science, Scopus, and the Cochrane Library databases to identify relevant studies before March 8, 2021. Stone-free rate (SFR), operation time, fever rate, hemoglobin drop, blood transfusion rate, and hospitalization time were used as outcomes to compare mini-PCNL and standard-PCNL. The meta-analysis was performed using the Review Manager version 5.4.

RESULTS

Seven randomized controlled trials were included in our meta-analysis, involving 1407 mini-PCNL cases and 1436 standard-PCNL cases. Our results reveal that, for renal stones >2cm, mini-PCNL has a similar SFR (risk ratio (RR)=1.01, 95% confidence interval (CI): 0.98 to 1.04, p=0.57) and fever rate (RR=1.22, 95% CI: 0.97-1.51, p=0.08). Standard-PCNL was associated with a significantly shorter operating time (weighted mean difference (WMD)=8.23, 95% CI: 3.44 to 13.01, p <0.01) and a longer hospitalization time (WMD=-20.05, 95% CI: -29.28 to -10.81, p <0.01) than mini-PCNL. Subgroup analysis showed hemoglobin drop and blood transfusion for 30F standard-PCNL were more common than mini-PCNL (WMD=-0.95, 95% CI: -1.40 to -0.50, p <0.01; RR=0.20, 95% CI: 0.07 to 0.58, p <0.01).

CONCLUSION

In the treatment of >2cm renal stones, mini-PCNL should be considered an effective and reliable alternative to standard-PCNL (30F). It achieves a comparable SFR to standard-PCNL, but with less blood loss, lower transfusion rate, and shorter hospitalization. However, the mini-PCNL does not show a significant advantage over the 24F standard-PCNL. On the contrary, this procedure takes a longer operation time.

TRIAL REGISTRATION

This meta-analysis was reported consistent with the PRISMA statement and was registered on PROSPERO, with registration number 2021CRD42021234893.

Pooled-analysis of efficacy and safety of minimally invasive versus standard percutaneous nephrolithotomy

BACKGROUND

This study aimed to assess the efficacy and safety of minimally invasive percutaneous nephrolithotomy (MPCNL) versus standard percutaneous nephrolithotomy in patients with renal and upper ureteric stones.

METHODS

We conducted a pooled analysis on randomized controlled trials (RCTs). The eligible RCTs were selected from the following databases: MEDLINE, Embase, Web of Science, and the Cochrane Library. The reference lists of retrieved studies were also investigated.

RESULTS

Our analysis included 10 RCTs with 1612 patients. Pooled data from 10 RCTs revealed the following: stone-free rate (odds ratio = 1.46, 95% confidence interval (CI) [1.12,1.88], P = .004), operative time (mean difference [MD]  = 4.10, 95% CI [-1.37,9.56], P = .14), length of hospital stay (MD = -15.31, 95% CI [-29.43,-1.19], P = .03), hemoglobin decrease (MD = -0.86, 95% CI [-1.19,-0.53], P < .00001), postoperative fever (MD = 0.83, 95% CI [0.49,1.40], P = .49), and urine leakage (MD = 0.59, 95% CI [0.25,1.37], P = .22). Besides, we performed sub-group analysis based on vacuum suction effect and multiple kidney stones. For vacuum suction effect, it revealed the following: stone-free rate in vacuum suction group (P = .007) and in non-vacuum suction group (P = .19). Operative time in vacuum suction group (P = .89), non-vacuum suction group (P = .16). Postoperative fever in vacuum suction group (P = .49), non-vacuum suction group (P = .85).

CONCLUSION

This pooled analysis indicated that MPCNL was a safe and effective method for treating renal stones compared with standard percutaneous nephrolithotomy. Besides, the vacuum suction effect in MPCNL played a more important role. When it comes to multiple or staghorn stones, the longer operative time in MPCNL could not be ignored.

Opioid-sparing analgesic effects of peripheral nerve blocks in percutaneous nephrolithotomy: a systematic review

INTRODUCTION

Multimodal analgesia regimens incorporating peripheral nerve blocks (PNB) have demonstrated reduced postoperative pain, opioid use, and recovery time in various disease states. However, this remains a subject of limited investigation in the percutaneous nephrolithotomy (PCNL) domain. In the face of an ongoing opioid epidemic and collective push to enhance prescribing stewardship, we sought to examine the potential opioid-sparing effect of PNB in PCNL.

METHODS

A systematic review of Embase and PubMed was performed to identify all randomized controlled trials evaluating the use of a PNB with general anesthesia (GA) versus GA alone for pain control following PCNL. Studies evaluating neuraxial (epidural and spinal) anesthesia and those without GA as the control arm were excluded.

RESULTS

Seventeen trials evaluating 1012 procedures were included. Five different blocks were identified and evaluated: paravertebral (n=8), intercostal nerve (n=3), quadratus lumborum (n=2), transversus abdominis plane (n=1), and erector spinae (n=3). 9/16 (56%) studies observed lower pain scores with PNB use throughout the 24-hour postop period. By comparison, improved pain scores with PNB were limited to the early (<6 hours) recovery period in 5 studies and 2 found no difference. Total analgesia and opioid requirements were significantly higher in the GA control arm in nearly all studies (12/14, 86%). Operative times were similar and there were no differences in rates of intercostal access or nephrostomy tube insertion between study arms in any trial.

CONCLUSION

While greater analgesic use with GA alone likely minimizes or obscures differences in patient-reported pain scores, PNB may offer a significant opioid-sparing analgesic effect during postoperative recovery after PCNL.

Mini-percutaneous nephrolithotomy is a safe alternative to extracorporeal shockwave lithotripsy for high-density, renal stones: a prospective, randomised trial

OBJECTIVES

To compare the outcomes of miniaturised percutaneous nephrolithotomy (mini-PCNL) and extracorporeal shockwave lithotripsy (ESWL) in the management of 10-20 mm, non-lower pole, renal stones.

PATIENTS AND METHODS

This prospective randomised double-arm trial was conducted at a tertiary care hospital in Egypt from February to December 2020. Adult patients with single, non-lower pole, high-density (≥1000 HU) renal stones were randomised to receive mini-PCNL or ESWL. The stone-free rate (SFR); operative, fluoroscopy and hospitalisation times; blood loss; auxiliary procedures; retreatment; unscheduled hospital readmission; and complications were compared between the groups.

RESULTS

The primary analysis included 34 patients in the mini-PCNL group and 33 in the ESWL group. Overall, the SFR was 97.1% in the mini-PCNL group vs 30.3% in the ESWL group (P < 0.001). All patients in the ESWL group required retreatment, and none of them were stone-free after the first ESWL session. None of the patients in the mini-PCNL group required retreatment. The overall operative time, fluoroscopy time, auxiliary procedure, retreatment, and unscheduled hospital readmission were significantly higher in the ESWL group. The hospital stay and decrease in the haemoglobin level were significantly higher in the mini-PCNL group. The groups were comparable for the overall complication rate.

CONCLUSIONS

Mini-PCNL is more effective than ESWL for treating 10-20 mm, high-density, non-lower pole renal stones. Mini-PCNL has the advantages of a high SFR and abolishing the need for retreatment and re-hospitalisation.

A systematic review and meta-analysis of minimally invasive vs. standard percutaneous nephrolithotomy in the surgical management of renal stones

The present study aimed to assess current evidence on the effectiveness and safety of minimally invasive vs. standard percutaneous nephrolithotomy (PCNL) in the management of renal stones. A systematic search of electronic databases, which included PubMed, EMBASE and the Cochrane Library up to May 2019 was performed. Using Review Manager statistical software (version 5.3), primary outcomes, including stone-free rates (SFRs), were evaluated. Meanwhile, analysis was also performed to compare secondary outcomes, such as peri- and postoperative complications and operative data. Fourteen studies involving 1,611 patients with renal stones were analyzed based on the inclusion criteria. On the basis of the present analysis, mini percutaneous nephrolithotomy (MPCNL) was proven to have non-inferior clinical efficacy with respect to the SFR compared with PCNL [odds ratio (OR)=1.10; 95% confidence interval (CI), 0.84-1.44; P=0.48]. In addition, the meta-analysis showed that MPCNL had a significantly lower hemoglobin decrease [mean difference (MD)=-0.68; 95% CI, -1.05 to -0.31; P=0.0003] and fewer blood transfusions (OR=0.36; 95% CI, 0.18-0.71; P=0.003) compared with PCNL. Moreover, the MPCNL group had a shorter inpatient stay (MD=-0.81; 95% CI, -1.55 to -0.08; P=0.03) compared with the PCNL group. However, the overall evidence was insufficient to suggest a statistically significant difference in the adverse event profile for MPCNL compared with PCNL. The present meta-analysis indicates that MPCNL is an effective method for treating renal stones. Compared with PCNL, MPCNL not only has similarly high SFRs but is also associated with less blood loss, fewer blood transfusions, more favorable recovery time and shorter inpatient stays. However, the findings of the present study should be further confirmed by well-designed prospective randomized controlled trials with a larger patient series.

Standard versus Mini-Percutaneous Nephrolithotomy for Renal Stones: A Meta-Analysis

Objective:

To compare the standard percutaneous nephrolithotomy and mini-percutaneous nephrolithotomy in order to determine the optimal tract size for patients with renal stones.

Methods:

A systematic search of Web of Science, EMBASE, Cochrane Library, and PubMed databases was conducted for articles published through 20 August 2019, reporting on a comparison of the standard percutaneous nephrolithotomy and mini-percutaneous nephrolithotomy using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

Results:

Of 763 studies, 14 were considered for the evidence synthesis. A total of 1980 cases were included. Of these patients, 897 cases underwent standard percutaneous nephrolithotomy, and 1083 cases underwent mini-percutaneous nephrolithotomy. Stone-free rates were 87.6% (786 of 897 patients) for standard percutaneous nephrolithotomy and 87.8% (951 of 1083 patients) for mini-percutaneous nephrolithotomy ( p = 0.57). Tract sizes of 30F and 22–26F in standard percutaneous nephrolithotomy group shorten operation time compared with mini-percutaneous nephrolithotomy ( p = 0.02; p = 0.004; respectively). Leakage ( p = 0.04), bleeding ( p = 0.01), blood transfusion ( p < 0.00001), and renal pelvis perforation ( p = 0.02) were more common in standard percutaneous nephrolithotomy group than in mini-percutaneous nephrolithotomy group. Subgroup analysis showed only blood transfusion for 30F and 22–26F standard percutaneous nephrolithotomy group was more common than mini-percutaneous nephrolithotomy ( p < 0.0001, p = 0.005, respectively).

Conclusion:

Standard percutaneous nephrolithotomy was associated with higher leakage, bleeding, blood transfusion, and renal pelvis perforation, but had a shorter operation time. Tract size of 30F improved the stone-free rate compared with mini-percutaneous nephrolithotomy, but led to more complications. Tract size of 22–26F was no better than 30F or mini-percutaneous nephrolithotomy.

Minimally invasive versus standard endoscopic combined intrarenal surgery for renal stones: a retrospective pilot study analysis

PURPOSE

The effect of combining miniaturization with endoscopic combined intrarenal surgery (ECIRS) is unclear. Thus, we compared the treatment outcomes between minimally invasive ECIRS (mini-ECIRS) using 16.5 Fr percutaneous access sheath and standard ECIRS using 24 Fr access sheath for renal stones MATERIALS AND METHODS: We retrospectively analyzed consecutive patients who underwent single session mini or standard-ECIRS in the modified Valdivia position for renal stones between April 2009 and May 2016. To adjust for patient characteristics, 77 pairs were matched using preoperative parameters including age, sex, history of febrile urinary tract infection (UTI), stone surface area, number of involved calyces, and staghorn calculi.

RESULTS

The stone free rate (SFR) was similar between mini and standard ECIRS according to non-contrast computed tomography (61.1% vs. 52.0%, p = 0.388). The rate of perioperative complications exceeding grade 2 based on the Clavien-Dindo classification was similar in both groups (19.5% vs. 26.0%, p = 0.442). Severe complications exceeding grade 3 were also similar in both groups (2.6% vs. 3.9%, p > 0.99). Two cases of septic shock were noted in each group. Although there was no difference regarding bleeding-related complications (2.6% vs. 6.5%, p = 0.442), pseudoaneurysm or blood transfusion was not observed in the mini-ECIRS group. Pain visual analog scale values in the perioperative period were lower in the mini-ECIRS group (1.34 ± 1.08 vs. 1.69 ± 1.23, p = 0.062).

CONCLUSIONS

This study demonstrated that, compared to standard ECIRS, mini-ECIRS maintained SFR without increasing perioperative complications, tended to reduce postoperative pain and had a potential to reduce bleeding-related complications. This report suggests the advantages of ECIRS miniaturization for renal stones.

Comparison of the efficacy and safety of shockwave lithotripsy, retrograde intrarenal surgery, percutaneous nephrolithotomy, and minimally invasive percutaneous nephrolithotomy for lower-pole renal stones: A systematic review and network meta-analysis

BACKGROUND

Shock wave lithotripsy (SWL), retrograde intrarenal surgery (RIRS), percutaneous nephrolithotomy (PCNL), and minimally invasive PCNL are currently therapeutic options for lower-pole renal stones (LPS). However, the optimal treatment for LPS remains unclear. A comprehensive evaluation of the efficacy and safety of each intervention is needed to inform clinical decision-making. This study aimed at assessing the efficacy and safety of different interventions for LPS.

METHODS

PubMed, Embase, ScienceDirect, ClinicalKey, Cochrane Library, ProQuest, Web of Science, and ClinicalTrials.gov were searched from inception to December 6th 2018. Only randomized controlled trials (RCTs) including the patients treated for LPS were included. The frequentist models of network meta-analysis were used to compare the effect sizes. The primary outcome was stone free rate, and the secondary outcomes were overall complication rate, major complication rate, retreatment rate, and auxiliary procedure rate.

RESULTS

This study included 13 RCTs comprising 1832 participants undergoing 6 different interventions, including RIRS, PCNL, Mini-PCNL, Micro-PCNL, SWL, and conservative observation. PCNL had the best stone free rate (odds ratio [OR] = 3.45, 95% confidence interval [CI] = 1.30-9.12), followed by Mini-PCNL (OR = 2.90, 95% CI = 1.13-7.46). Meta-regression did not find any association of the treatment effect with age, sex, and stone size. Although PCNL tended to exhibit a higher complication rate, the difference of complication rate among various interventions did not achieve a statistical significance. SWL was the less effective and associated with higher retreatment rate compared with PCNL, Mini-PNCL, and RIRS.

CONCLUSIONS

PCNL was associated with the best stone free rate for LPS regardless of age, sex, and stone size. Each treatment achieved a similar complication rate compared with the others. Future large-scale RCTs are warranted to identify the most beneficial management for renal stones at a more complicated location.

Tract sizes in percutaneous nephrolithotomy: does miniaturization improve outcome?

PURPOSE OF REVIEW

To provide a summary of surgical outcomes in percutaneous nephrolithotomy (PCNL) according to various techniques and tract sizes.

RECENT FINDINGS

Recent literature in this field concluded that standard PCNL (sPCNL) remains the optimal treatment for stones between 1 and 2.5 cm and can be managed with tracts 14-20 F, whereas small stones less than 1.5 cm can be treated with tracts under 14 F. According to new datasets, smaller tracts can be equally effective in the treatment and might offer the possibility to reduce bleeding, length of hospital stay, postoperative pain as well as overall complication rates when compared with sPCNL. On the other hand, longer operative time as well as lower stone-free rates, which have been the main drawbacks of the miniaturized approach, have recently shown to be comparable with sPCNL.

SUMMARY

At present, tract size is a highly debatable topic in percutaneous stone therapy. New systems for miniaturized PCNL have been developed to achieve comparable stone-free rates while reducing the incidence of common complications. The adoption of these techniques demands skilled surgeons and institutional investment for the acquisition of new equipment.

Treatment of renal calculi without hydronephrosis using a standard channel assisted by a visual puncture system

Objective

To study the safety and efficacy of standard channel establishment using a visual puncture system in the treatment of renal calculi without hydronephrosis.

Methods

We retrospectively analyzed data from 46 patients undergoing percutaneous nephrolithotomy via a standard channel assisted by a visual puncture system, including number of punctures, duration of procedure, hemoglobin level after surgery, calculi clearance rate, and postoperative complications.

Results

Sixty-nine channels were established, including a single channel in 26 cases, double channel in 17 cases, and three channels in 3 cases. The mean number of punctures was 1.50, mean time to establish the standard channel was 2.6 minutes, and duration of surgery was 31.3 minutes. No significant change in hemoglobin was observed after surgery. Forty-three patients had no residual calculi and three had small residual calculi on the day after surgery, representing a first-phase clearance rate of 93.48% (43/46). No significant complications were observed.

Conclusions

Hemorrhage during operation can be significantly reduced by establishing a standard channel using a visual puncture system. Moreover, the number of standard channels can be reduced and the incidence of complications lowered using this approach, which should be adopted widely for the treatment of renal calculi without hydronephrosis.

Minimally invasive percutaneous nephrolithotomy versus retrograde intrarenal surgery in surgical management of upper urinary stones - A systematic review with meta-analysis

OBJECTIVE

The purpose of this study was to retrospectively assess the efficacy and safety of minimally invasive nephrolithotomy (MPCNL) versus retrograde intrarenal surgery (RIRS) in the management of upper urinary stones.

METHODS

A comprehensive literature review of articles that investigated the efficacy and safety of MPCNL and RIRS was conducted by systematically searching PubMed, EMBASE, and Cochrane Library in March 2019. Two reviewers searched the literature, independently extracted the data and evaluated the quality of the data according to the inclusion and exclusion criteria. A meta-analysis was performed by using Review Manager 5.3 software.

RESULTS

Eight randomized controlled trials (RCTs) involving 725 patients with upper urinary stones were analysed based on the inclusion criteria. While MPCNL has a better clinical efficacy than RIRS with respect to the stone-free rate (SFR) [RR = 1.11, 95% CI (1.05-1.17), p = 0.0005], MPCNL has a higher incidence of haematoma [RR = 3.09, 95% CI (1.44-6.66), p = 0.004] and longer hospitalization time [MD = 0.89 day, 95% CI (0.07-1.72), p = 0.04]. In addition, no significant difference in operative time [MD = 2.46 min, 95% CI (-17.99 to 22.92), p = 0.81] and postoperative pain score [MD = 0.74, 95% CI (-0.45 to 1.94), p = 0.22] were observed between the two methods. Overall, the evidence was insufficient to suggest a statistically significant difference in the adverse event profile for MPCNL compared with RIRS.

CONCLUSIONS

Our data suggest that MPCNL is an effective method for treating upper urinary stones, especially lower calyceal stones that are 1-2 cm in size. Compared to RIRS, MPCNL is associated with a longer hospital stay time and a higher incidence of haematoma. In addition, both methods have proven to be safe. Nevertheless, the findings should be further confirmed through well-designed prospective RCTs with a larger patient series.

Reducing postoperative morbidity of mini-invasive percutaneous nephrolithotomy: Would it help if blood vessels are left unharmed during puncture? A CONSORT-prospective randomized trial

BACKGROUND

The aim of this study was to provide a randomized controlled trial comparing single B-mode ultrasound guidance and color doppler ultrasound guidance in minimally invasive percutaneous nephrolithotomy.

METHODS

Three hundred patients with renal calculus were prospectively randomly assigned into 2 groups. In group 1 (150 patients), minimally invasive percutaneous nephrolithotomy (m-PCNL) were managed with single B-mode ultrasound guidance; In group 2 (150 patients), m-PCNL were managed with color Doppler ultrasound guidance and a needle bracket in order to guide placement at a target location beneath the skin. The characteristics of patients, operation, complications and prognosis, including body temperature, urine culture, and hematologic tests after the operation were recorded and compared.

RESULTS

Our vessel-sparing technique showed a statistically significant decrease in hemoglobin drop, postoperative procalcitonin values, the frequency of postoperative fever, systemic inflammatory response syndrome, and urosepsis (P < .05).

CONCLUSION

Using color Doppler ultrasound in real time and a needle bracket to detect and avoid main renal blood vessels decreased incidences of hemorrhagic complications and postoperative infection.

Mini vs standard percutaneous nephrolithotomy for renal stones: a comparative study

To compare the outcome of mini-percutaneous nephrolithotomy (Mini-PNL) versus standard-PNL for renal stones. Retrospective study was performed between March 2010 and May 2013 for patients treated by Mini-PNL or standard-PNL through 18 and 30 Fr tracts, respectively, using pneumatic lithotripsy. Semirigid ureteroscope (8.5/11.5 Fr) was used for Mini-PNL and 24 Fr nephroscope for standard-PNL. Both groups were compared in stone free rate(SFR), complications and operative time using Student-t, Mann-Whitney, Chi square or Fisher's exact tests as appropriate in addition to logistic regression analysis. P < 0.05 was considered statistically significant. Mini-PNL (378) and standard-PNL (151) were nearly comparable in patients and stones criteria including stone burden (3.77 ± 2.21 vs 3.77 ± 2.43 cm²; respectively). There was no significant difference in number of tracts or supracostal puncture. Mini-PNL had longer operative time (68.6 ± 29.09 vs 60.49 ± 11.38 min; p = 0.434), significantly shorter hospital stay (2.43 ± 1.46 vs 4.29 ± 1.28 days) and significantly higher rate of tubeless PNL (75.1 vs 4.6%). Complications were significantly higher in standard-PNL (7.9 vs 20.5%; p < 0.001). SFR was significantly lower in Mini-PNL (89.9 vs 96%; p = 0.022). This significant difference was found with multiple stones and large stone burden (> 2 cm²), but the SFR was comparable between both groups with single stone or stone burden ≤ 2 cm. Logistic regression analysis confirmed significantly higher complications and SFR with standard-PNL but with significantly shorter operative time. Mini-PNL has significantly lower SFR when compared to standard-PNL (but clinically comparable) with markedly reduced complications and hospital stay. Most of cases can be performed tubeless. The significant difference in SFR was found with multiple stones or large stone burden (> 2 cm²), but not with single stones or stone burden ≤ 2 cm².