Left endoscopic combined intrarenal surgery with electrocoagulation hemostasis and right flexible ureteroscopic lithotripsy for bilateral upper urinary tract stones: a case report

Background

Percutaneous nephrolithotomy (PCNL) is the first-line treatment for large renal stones. However, multi-tract or staged procedures may be necessitated in bilateral or anatomically-complex stones to achieve stone clearance. Endoscopic combined intrarenal surgery (ECIRS) integrates the advantages of PCNL and retrograde intrarenal surgery. In this article, we detail a hybrid surgical technique adopted for the management of complex simultaneous bilateral upper urinary tract stones. In addition, we discuss the advantages and disadvantages of combining a variety of new techniques that may improve post-operative outcomes and patient satisfaction.

Case Description

We report the case of a 36-year-old male with a large left renal pelvis stone, right proximal ureteric stone, and bilateral renal stones. Biochemical results showed raised inflammatory markers but he denied pre-stenting and staged surgery. After receiving 3-day antibiotic prophylaxis, he underwent an elective hybrid procedure. Under split-leg prone position, we performed a hybrid procedure that included left ECIRS with tubeless single-tract mini PCNL and left flexible ureteroscopy, and right flexible ureteroscopic lithotripsy. Hemostasis was achieved by electrocauterization with a novel device. The patient made an uneventful recovery. Follow-up computed tomography (CT) at 1-month revealed complete stone clearance.

Conclusions

Unilateral ECIRS with tubeless single-tract mini PCNL with electrocoagulation hemostasis and adjacent retrograde intrarenal surgery in split-leg prone position is a safe, feasible, and efficient technique to manage large renal stones.

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.

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.

Regulatory effect of Pseudomonas aeruginosa mannose-sensitive hemagglutinin on inflammation and immune function in percutaneous nephrolithotomy patients with upper urinary tract calculi complicated with infection

Objective

To study the effect of an injection of Pseudomonas aeruginosa mannose-sensitive hemagglutinin (PA-MSHA) on inflammation and immune function in patients with upper urinary tract calculi complicated by infection who have undergone percutaneous nephrolithotomy.

Methods

We retrospectively recorded the clinical data of patients with upper urinary tract calculi complicated by infection who have undergone Percutaneous nephrolithotomy(PCNL) in the Department of Urology, 2nd Affiliation Hospital of Kunming Medical University, from March to December 2021. Clinical data include general condition, laboratory index, CT, postoperative body temperature, heart rate, respiration, SIRS, sepsis, etc. Patients were divided into treated and control groups according to whether they had received a preoperative PA-MSHA injection. The two groups were compared for indices of inflammation and complications of infection after PCNL. Pre- and post-operative lymphocyte subsets and immunoglobulin changes were compared.

Results

115 patients were included in the study, including 43 in the treatment group and 72 in the control group. After Propensity Score Matching, 90 patients were divided into treatment (n=35) and control (n=55) groups. The postoperative inflammation index was higher in the treatment group than in the control group (P<0.05). The incidence of postoperative SIRS was higher in the treatment group than control (P<0.05). There were no cases of sepsis in either group. The double-positive T cells lymphocyte subsets were higher in the treatment group than in the control group ((P<0.05). Pre- and post-operative changes in immune function: total T lymphocyte count reduced, NK and NKT cell count increased in the control group, double-positive T cell count increased in the treatment group, IgG, IgA, IgM, complement C3 and C4 count reduced in both groups post-operatively.

Conclusion

This study found that patients with upper urinary tract calculi and infection treated with antibiotic-based PA-MSHA before percutaneous nephrolithotomy had an increased inflammatory response after surgery, which may play a role in the prevention and treatment of sepsis. The percentage of double-positive T cells in the peripheral blood was increased after PA-MSHA treatment, which may have an immunomodulatory and protective effect in PCNL patients with stones complicated by infection.

Giant staghorn stone causing inferior vena cava compression: a novel case report

Staghorn calculi (SC) are defined as large kidney stones that fill the renal pelvis and at least one renal calyx. They represent 10-20% of all renal stones in developing countries and require prompt diagnosis and management. Massive SC (over 5 cm) are treated exclusively via open surgery, despite percutaneous nephrolithotomy (PCNL) being the gold standard treatment for large stones. Descriptions of PCNL for massive SC are very limited in the literature.

Case Presentation

We report a case of a 63-year-old male who presented with chronic abdominal pain, hepatosplenomegaly, and normal renal function. He was later diagnosed with polycythemia vera. Computed tomography of the abdomen revealed massive, bilateral staghorn stones measuring 7.3×5.5 cm and 1.8×4.5 cm on the right and left, respectively. Additionally, the right stone was found to be compressing the inferior vena cava (IVC). The patient was promptly scheduled for right-sided PCNL and the target of 80% stone fragmentation was successfully attained.

Discussion

We present the first case of a stone of such size in the Middle East, as well as the first known case of a renal stone compressing the IVC. Unlike previous reports, the stone was successfully fragmented via PCNL - a procedure that has not been described for stones of such size.

Conclusion

This report highlights that ultrasound-guided PNCL without any other intervention is sufficient for the successful treatment of giant SC. Greater research is needed on the potential utility of using ultrasound-guided PCNL for the fragmentation of stones sized over 5 cm.

Comparison of Superpulse Thulium Fiber Laser vs Holmium Laser for Ablation of Renal Calculi in an In Vivo Porcine Model

Introduction and Objectives: We sought to compare the effectiveness and efficiency of the superpulse thulium fiber laser (sTFL to the holmium: yttrium-aluminum-garnet [Ho:YAG] laser for ureteroscopic "dusting" of implanted renal stones in an in vivo porcine model. Methods: Twenty-four porcine kidneys (12 juvenile female Yorkshire pigs) were randomized to Ho:YAG or sTFL treatment groups. Canine calcium oxalate stones were scanned with computed tomography to calculate stone volume and stone density; the stones were randomized and implanted into each renal pelvis via an open pyelotomy. In all trials, a 14F, 35 cm ureteral access sheath was placed. With a 9.9F dual lumen flexible ureteroscope, laser lithotripsy was performed using dusting settings: Ho:YAG 200 μm laser fiber at 16 W (0.4 J, 40 Hz) or sTFL 200 μm laser fiber at 16 W (0.2 J, 80 Hz). Lithotripsy continued until no fragments over 1 mm were observed. No stone basketing was performed. Throughout the procedures, intrarenal and renal pelvis temperatures were measured using two percutaneously positioned K-type thermocouples, one in the upper pole calyx and one in the renal pelvis. After the lithotripsy, the ureteropelvic junction was occluded, the kidneys were bivalved, and all residual fragments were collected, dried, weighed, and then measured with an optical laser particle sizer. Results: Implanted stones were similar in volume and density in both groups. Intraoperative collecting system temperatures were similar for both groups (all <44°C). Compared to Ho:YAG, sTFL ablated stones faster (9 vs 27 minutes, p < 0.001) with less energy expenditure (8 vs 26 kJ, p < 0.001), and a greater stone clearance rate (73% vs 45%, p = 0.001). After sTFL lithotripsy, 77% of the remaining fragments were ≤1 mm vs 17% of fragments ≤1 mm after Ho:YAG treatment (p < 0.001). Conclusions: In an in vivo porcine kidney, using dusting settings, sTFL lithotripsy resulted in shorter ablation times, higher stone clearance rates, and markedly smaller stone fragments than Ho:YAG lithotripsy.

Comparison of paravertebral block vs. general anesthesia for percutaneous nephrolithotomy: A retrospective study

Background

General anesthesia is used in the majority of patients undergoing percutaneous nephrolithotomy. To reduce the general anesthesia-related risks and complications, this study evaluated the efficacy and safety of the paravertebral block as a novel and alternative anesthetic method for percutaneous nephrolithotomy.

Methods

This was a retrospective study. A total of 198 patients under percutaneous nephrolithotomy were included. Among them, 76 patients received paravertebral block and 122 received general anesthesia. Patients' characteristics, surgical outcomes, anesthetic outcomes, and perioperative complications and the visual analog scale (VAS) were recorded to evaluate the efficacy and safety of paravertebral block compared with general anesthesia. Intergroup differences of the parameters were analyzed using an independent t-test and χ²-tests appropriate.

Results

Seventy-six patients who underwent paravertebral block completed the surgery successfully, three patients were supplemented with propofol for discomfort during ureteroscopy, and two patients were supplemented with remifentanil for incomplete nerve blockade. Patients who underwent paravertebral block had a higher American Society of Anesthesiologists grade and heart function grade, including patients with contraindications to general anesthesia. Intraoperative and postoperative adverse events and the anesthesia costs were less in patients who underwent paravertebral block. VAS pain scores during the postoperative period in patients who underwent paravertebral block were lower than those in patients who underwent general anesthesia without the use of patient-controlled intravenous analgesia.

Conclusion

In this retrospective study, paravertebral block was found to be effective and safe in providing intraoperative anesthesia for percutaneous nephrolithotomy, and had less adverse events and anesthesia costs. Paravertebral block is an attractive alternative anesthesia for patients at increased risk of comorbidities following general or neuraxial anesthesia.

Performing percutaneous nephrolithotomy under modified local anesthesia

Objective

This pilot study aimed to assess the practicability and effectiveness of percutaneous nephrolithotomy (PCNL) with vacuum-assisted nephrostomy sheaths for patients under modified local anesthesia (m-LA).

Methods

PCNL with a vacuum-assisted nephrostomy sheath under m-LA was performed in 83 patients between November 2020 and May 2021. An 18F or 20F ClearPetra Nephrostomy Sheath connected vacuum aspiration was used in surgery to keep low pressure in the renal pelvis. For LA, lidocaine and ropivacaine hydrochloride were 1:1 mixed and instilled under ultrasound guidance through the percutaneous nephrolithotomy channel directed toward the design calix. Demographic characteristics, stone characteristics, visual analogue scale (VAS) score, vital signs, operation time, complications, and stone clear rate were recorded and analyzed.

Results

All operations were completed. The mean VAS score was 3.9 ± 1.0. The mean operation time was 55.1 ± 23.6 min. The changes for systolic blood pressure, diastolic blood pressure, and heart rate were 3 ± 21 mmHg, 1 ± 14 mmHg, and −6 ± 14 beats/min, respectively. The change for hemoglobin was −10.7 ± 10.9 g/L. The change for C-reactive protein was 5.39 ± 43.1 mg/L. The total stone-free rate was 69.9% (93.8% for simple stones and 54.9% for complex stones).

Conclusion

Performing PCNL with vacuum-assisted nephrostomy sheaths under modified local anesthesia under ultrasound guidance was found to be strongly practical and effective.

A novel approach in creating nephrostomy using a double-lumen access sheath during endoscopic combined intrarenal surgery

Background

This study aimed to evaluate the safety and efficacy of an inner ureteral access sheath (i-UAS) with a double-lumen channel used in ureteroscopic lithotripsy (URS) as a dilator for the percutaneous tract in endoscopic combined intrarenal surgery (ECIRS).

Methods

This was a single-center cohort study conducted from January 2016 to April 2020. We used an i-UAS as a dilator and a double-lumen catheter to insert a safety guidewire during the creation of the nephrostomy tract in ECIRS. Univariate and multivariate analyses were performed to assess the association between the perioperative parameters and the use of i-UAS. The primary endpoint was perioperative complications, and secondary endpoints were stone-free rate (SFR), operative time, fluoroscopy time, and duration of hospitalization.

Results

In total, 221 patients were enrolled during the study period. Patients were divided into an i-UAS dilation group (n=108) and a one-shot dilation group (n=113). No differences were observed between the two groups in terms of patient history. Univariate analyses indicated that, in the i-UAS dilation group, the operative time was shorter [105.50 (83.75–143.25) vs. 121.00 (90.00–155.00) min; P=0.02] and the modified Valdivia position was more frequently selected. Multivariate analyses showed no significant differences in the frequency of complications, such as urinary injury or postoperative pyelonephritis, but it showed a significantly shorter operative time as well as fewer tract creation troubles in the i-UAS dilation group.

Conclusions

Using an i-UAS as a dilator and a double-lumen catheter to insert a safety guidewire during ECIRS is a convenient and safe technical method for creating a nephrostomy tract that can reduce the operative time.

Pediatric Urolithiasis: Current Surgical Strategies and Future Perspectives

New technological innovations and cutting-edge techniques have led to important changes in the surgical management of pediatric urolithiasis. Miniaturized technologies and minimally invasive approaches have been increasingly used in children with urinary stones to minimize surgical complications and improve patient outcomes. Moreover, the new computer technologies of the digital era have been opening new horizons for the preoperative planning and surgical treatment of children with urinary calculi. Three-dimensional modeling reconstructions, virtual, augmented, and mixed reality are rapidly approaching the surgical practice, equipping surgeons with powerful instruments to enhance the real-time intraoperative visualization of normal and pathological structures. The broad range of possibilities offered by these technological innovations in the adult population finds increasing applications in pediatrics, offering a more detailed visualization of small anatomical structures. This review illustrates the most promising techniques and devices to enhance the surgical treatment of pediatric urolithiasis in children, aiming to favor an early adoption and to stimulate more research on this topic.

Efficacy and safety of ultrasound-guided percutaneous nephrolithotomy for kidney calculi patients with ankylosing spondylitis: a retrospective single center analysis

BACKGROUND

To investigate the efficacy and safety of ultrasound-guided percutaneous nephrolithotomy (PCNL) in kidney calculi patients with ankylosing spondylitis (AS).

METHODS

The data of 22 renal stone patients (25 kidney units) with AS who underwent PCNL in our institute from January 2008 to December 2019 were analyzed retrospectively. General information of these patients, intraoperative and postoperative data were recorded. The primary parameter for efficacy was initial and final stone free rates (SFR) with X-ray kidney, ureter, and bladder (KUB) were performed 1st or 2nd day and 1 month after surgery. Preoperative and postoperative laboratory results, surgical procedures and the occurrence of postoperative complications were used to identify the safety PCNL intervention.

RESULTS

Most PCNLs were performed with general anesthesia (76%) and prone position (64%). The initial SFR and final SFR were 80% (20 kidney units) and 88% (22 kidney units) respectively. Haemoglobin decreased after PCNL occurred in 22 patients (88.0%) and the mean postoperative hemoglobin drop was 1.32±0.76 g/L (range, 0.10-3.10 g/L), with one patient received blood transfusion. One patient developed postoperative fever (T >38.5 °C). No other complications such as colon injury, extravasation of urine, perinephric infection and urosepsis occurred.

CONCLUSIONS

The result of ultrasound-guided PCNL for kidney stone patients with AS is satisfactory with high SFR and security. Operative position, anesthesia method and damage caused by drugs used in the treatment of AS should be considered to achieve better result.

Clinical application of a special postoperative position cushion for patients after percutaneous nephrolithotomy: a randomized trial

BACKGROUND

Percutaneous nephrolithotomy (PCNL), a minimally invasive technique, has gradually replaced traditional open surgery in the treatment of upper urinary tract stones. The aim of this study was to observe the effects of a new special position cushion for PCNL in the clinical application.

METHODS

Four-hundred and fifty patients (229 males and 221 females, at the age of 47.03±8.9 years) after PCNL were randomly divided into two groups: the control group and the experimental group (n=225/each group). Patients in the control group were treated with conventional hip sponge pads to prevent from pressure ulcers after PCNL, and patients in the experimental group used the postoperatively special position cushion which included a sacrococcygeal pad and a back pad. We observed and compared patient's position comfort, the incidence of renal hemorrhage, removal rate of the renal fistula, folding rate of the renal fistula and incidence of refractory pressure ulcer between two groups.

RESULTS

Compared to the control group, the position comfort of the experiment group was improved. The incidence of renal hemorrhage due to improper postoperative position (hereinafter referred to as the incidence of renal bleeding), the rate of devascularization of the renal fistula, the rate of tube folding of the renal fistula, and the incidence of postoperative pressure ulcers in the experiment group were decreased in comparison with the control group, with significant differences (P<0.05).

CONCLUSIONS

The special position cushion increases the patient's comfort, improves the fix effect of the renal fistula, and effectively reduces the occurrence of adverse reactions such as bleeding and pressure sore caused by improper PCNL postoperative position.

Effectiveness of Percutaneous Nephrolithotomy, Retrograde Intrarenal Surgery, and Extracorporeal Shock Wave Lithotripsy for Treatment of Renal Stones: A Systematic Review and Meta-Analysis

Background and objectives: To perform a updated systematic review and meta-analysis comparing effectiveness of percutaneous nephrolithotomy (PCNL), retrograde intrarenal surgery (RIRS), and extracorporeal shock wave lithotripsy (ESWL) for treatment of renal stones (RS). Materials and Methods: A total of 37 studies were included in this systematic review and meta-analysis about effectiveness to treat RS. Endpoints were stone-free rates (SFR), incidence of auxiliary procedure, retreatment, and complications. We also conducted a sub-analysis of ≥2 cm stones. Results: First, PCNL had the highest SFR than others regardless of stone sizes and RIRS showed a higher SFR than ESWL in <2 cm stones. Second, auxiliary procedures were higher in ESWL than others, and it did not differ between PCNL and RIRS. Finally, in <2 cm stones, the retreatment rate of ESWL was higher than others. RIRS required significantly more retreatment procedures than PCNL in ≥2 cm stones. Complication was higher in PCNL than others, but there was no statistically significant difference in complications between RIRS and PCNL in ≥2 cm stones. For ≥2 cm stones, PCNL had the highest SFR, and auxiliary procedures and retreatment rates were significantly lower than others. Conclusions: We suggest that PCNL is a safe and effective treatment, especially for large RS.

Effectiveness of Percutaneous Nephrolithotomy, Retrograde Intrarenal Surgery, and Extracorporeal Shock Wave Lithotripsy for Treatment of Renal Stones: A Systematic Review and Meta-Analysis

Background and objectives: To perform a updated systematic review and meta-analysis comparing effectiveness of percutaneous nephrolithotomy (PCNL), retrograde intrarenal surgery (RIRS), and extracorporeal shock wave lithotripsy (ESWL) for treatment of renal stones (RS). Materials and Methods: A total of 37 studies were included in this systematic review and meta-analysis about effectiveness to treat RS. Endpoints were stone-free rates (SFR), incidence of auxiliary procedure, retreatment, and complications. We also conducted a sub-analysis of ≥2 cm stones. Results: First, PCNL had the highest SFR than others regardless of stone sizes and RIRS showed a higher SFR than ESWL in <2 cm stones. Second, auxiliary procedures were higher in ESWL than others, and it did not differ between PCNL and RIRS. Finally, in <2 cm stones, the retreatment rate of ESWL was higher than others. RIRS required significantly more retreatment procedures than PCNL in ≥2 cm stones. Complication was higher in PCNL than others, but there was no statistically significant difference in complications between RIRS and PCNL in ≥2 cm stones. For ≥2 cm stones, PCNL had the highest SFR, and auxiliary procedures and retreatment rates were significantly lower than others. Conclusions: We suggest that PCNL is a safe and effective treatment, especially for large RS.

The clinical research of 1,470 nm laser in percutaneous nephrolithotomy

Background

Percutaneous nephrolithotomy (PCNL) is the primary method for the treatment of renal calculi. The preservation of the nephrostomy tube after operation brings severe pain to the patients. We use a 1,470 nm semiconductor laser to stop bleeding after the operation, which cannot reserve the nephrostomy tube, fully reflect its safety and effectiveness, and provide a new method for clinical practice.

Methods

Forty-two patients with renal stones who came to our hospital from March 2016 to September 2019 were randomly divided into two groups: laser operation group (20 patients) and traditional operation group (22 patients). The stone removal rate, surgical effect, and postoperative complications were compared between the two groups.

Results

There was no significant difference in the stone clearance rate between the two groups at the 4th week after operation (P>0.05). However, the incidence of postoperative infection, incision pain, and massive bleeding in the laser surgery group were lower than those in the traditional surgery group (P<0.05). However, there was no significant difference in urine extravasation and postoperative hematuria between the two groups (P>0.05). The average postoperative hospital stay in the laser surgery group was shorter than that in the traditional surgery group, and the difference was statistically significant (P<0.05). Simultaneously, there was no significant difference in operation time, intraoperative blood loss, and medical expenses between the two groups (P>0.05).

Conclusions

The 1,470 nm laser is safe, effective, and feasible in PCNL operation, especially in hemostasis of the renal puncture channel, and it is worth popularizing.

Risk factors for the fever after percutaneous nephrolithotomy: a retrospective analysis

Background

It’s very common to see the onset of fever after percutaneous nephrolithotomy (PCNL), it’s necessary to analyze the risk factors for the fever following PCNL, and to provide evidence for infection prevention after PCNL.

Methods

A total of 546 adult PCNL patients were included as study subjects and retrospective studies were performed. We collected clinical data of patients using a prospectively designed database. Univariate and multivariate logistic regression analyses were performed to identify the potential risk factors for the fever after PCNL.

Results

Of the included 546 PCNL patients, there were 82 fever patients and 464 no-fever patients following PCNL. Escherichia coli and Proteus mirabilis are the two most common infectious bacteria. Preoperative urinary tract infection (OR =4.38, 95% CI: 1.15–9.53), multiple access (OR =5.31, 95% CI: 1.23–10.75), diabetes (OR =4.97, 95% CI: 1.37–9.86), length of operation ≥60 min (OR =5.67, 95% CI: 2.24–13.42), estimated blood loss in PCNL ≥500 mL (OR=2.78, 95% CI: 2.32–3.61) were the independent risk factors associated with postoperative infection.

Conclusions

Effective control of urinary tract infection, reduction of access number, strict control of blood glucose, length of operation control, reduction of intraoperative bleeding should be considered as measures to prevent postoperative fever for patients with PCNL.

Comparison of intrarenal pelvic pressure and postoperative fever between standard- and mini-tract percutaneous nephrolithotomy: a systematic review and meta-analysis of randomized controlled trials

Background

High intrarenal pelvic pressure (IPP) induces systemic absorption of irrigation fluid containing bacteria or endotoxins, which is associated with postoperative fever (POF) and even urosepsis. The emphasis of this meta-analysis lies in comparison of IPP and POF between mini-tract percutaneous nephrolithotomy (MPCNL) and standard-tract percutaneous nephrolithotomy (SPCNL).

Methods

Eligible randomized controlled trials (RCTs) were identified from electronic databases from inception to November 2019. Studies selection, quality assessment, data extraction and analysis were accomplished by two independent reviewers using Cochrane Collaboration’s tools.

Results

Patients in the MPCNL group experienced higher IPP compared to SPCNL group [mean difference (MD): 8.31, 95% confidence interval (CI): 3.67–12.96, P=0.0005] with highly between-study heterogeneity (P=0.001, I²=85%). Notably, the IPP was higher in MPCNL group in different stages of the procedure including introduction, fragmentation and end. However, only two trials were available for pooled analysis. Additionally, the risk of POF in MPCNL was 2.43 times higher than that in SPCNL [odds ratio (OR): 2.43, 95% CI: 1.39–4.27, P=0.002] with no significant between-study heterogeneity (P=0.83, I²=0%). The two procedures was comparable on stone-free rate (SFR) (OR: 1.06, 95% CI: 0.61–1.86, P=0.83) and operation time (MD: 5.69, 95% CI: −4.54 to 15.91, P=0.28).

Conclusions

Current evidence indicates that MPCNL is an effective alternative to SPCNL with comparable SFR. IPP and POF is significantly higher during MPCNL compared to SPCNL. Intraoperative detection of IPP is of great significance for ensuring safety and reducing postoperative complications, especially for patients with MPCNL and the duration of stone fragmentation. Further large well-designed trials are warranted to confirm our findings.

Risk factors for hemorrhage requiring embolization after percutaneous nephrolithotomy: a meta-analysis

Background

The aim of this meta-analysis was to systematically review and identify the risk factors for severe hemorrhage after percutaneous nephrolithotomy (PCNL).

Methods

We searched the PubMed and EMBASE database for literature related to the risk factors of severe hemorrhage after PCNL requiring angiography and embolization through to September 2019. The necessary data for each eligible study were extracted by 2 independent reviewers. The Newcastle-Ottawa Scale (NOS) was used for assessing the methodological quality of the included studies. Statistical analyses were conducted using Comprehensive Meta-Analysis version 2 to identify whether there was a statistical association between risk factors and severe hemorrhage post-PCNL.

Results

The results of this meta-analysis showed that urinary tract infection (UTI) (OR =1.98, 95% CI, 1.21–3.26, P=0.007), diabetes mellitus (OR =4.07, 95% CI, 1.83–9.06, P=0.001), staghorn stone (OR =3.49, 95% CI, 1.25–9.76, P=0.017), and multiple tracts (OR =2.09, 95% CI, 1.33–3.28, P=0.001) were independent risk factors for severe hemorrhage post-PCNL, while hypertension (OR =1.18, 95% CI, 0.58–2.42, P=0.65) showed no significant statistical difference.

Conclusions

Urologists should focus on the above identified risk factors for severe hemorrhage post-PCNL, including UTI, diabetes mellitus, staghorn stone, and multiple tracts. More high-quality studies with larger sample sizes are needed to validate these conclusions.

Prone percutaneous nephrolithotomy: its advantages and our technique for puncture

Percutaneous nephrolithotomy (PCNL) is considered the treatment of choice for large urinary calculi and staghorn lithiasis. The approach for this surgery may be either supine or prone, and different access techniques are described in the literature with the use of ultrasound, fluoroscopy, or both combined. We believe that prone PCNL offers to the urologist key advantages, such as the possibility of puncturing anatomically abnormal urinary tracts, to perform multiple percutaneous tracts in the same kidney, experiencing the vacuum cleaner effect, ease of exploring the upper calyx through the inferior calyx, possibility to perform endoscopic combined intrarenal surgery (ECIRS) and bilateral simultaneous surgery, and to performed over local anesthesia. An adequate training for the endourologist should include both the prone and supine techniques for PCNL and to know which patient can benefit the most from each one.

Coexisting intrarenal arteriovenous and caliceovenous fistulae after percutaneous nephrolithotomy: Case report and literature review

A 58-year-old man was re-admitted to the Urology service with delayed gross hematuria and unstable he-modynamics, following a percutaneous nephrolithotomy (PCNL) procedure performed for an obstructive solitary left lower calyceal stone. A selective left renal angiogram demonstrated an interpolar arteriovenous fistula (AVF), which was treated with successful coil embolization of a sub-segmental feeding branch. Sub-sequent nephrostogram confirmed a coexisting caliceovenous fistula, which was observed and healed spon-taneously. Iatrogenic coexisting intrarenal AVF and caliceovenous fistulae have never been reported and should be considered as a possible cause of delayed severe hematuria with unstable hemodynamics, and/or increase in baseline creatinine after PCNL.