Complete Ultrasound-guided Percutaneous Nephrolithotomy in Prone and Supine Positions: A Randomized Controlled Study

Efficacy and safety of ultrasound- vs fluoroscopy-guided percutaneous nephrolithotomy in managing renal calculi: A systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

To evaluate the effectiveness and safety of ultrasound-guided percutaneous nephrolithotomy (UG-PCNL) compared to fluoroscopy-guided PCNL (FG-PCNL) for kidney stone management, focusing on clinical outcomes and procedural efficiency.

METHODS

A systematic review and meta-analysis of randomized controlled trials (RCTs) was conducted following PRISMA guidelines. Searches were performed in PubMed, EMBASE, Scopus, and Web of Science for studies published between 2000 and 2024. Primary outcomes included stone-free rate (SFR), needle puncture time (NPT), calculus clearance rate (CCR), and access time. Secondary outcomes involved single needle puncture success rate (SNPSR), hospital stay duration (HSD), total complication rate (TCR), urosepsis, fever and postoperative serum creatinine.

RESULTS

Analysis of 21 RCTs with 2969 patients showed no significant difference in SFR between UG-PCNL and FG-PCNL (OR: 0.93, 95% CI: 0.77-1.13; p = 0.47). UG-PCNL significantly reduced access time (SMD: 0.68, 95% CI: 0.06-1.30; p = 0.03), while other outcomes like SNPSR and puncture time showed no significant differences. Complication rates, including urosepsis and fever, were comparable between techniques.

CONCLUSIONS

UG-PCNL is as effective as FG-PCNL, offering the benefits of radiation-free imaging and reduced access time, with comparable safety profiles. Further studies are needed to confirm the certainty of outcomes like SNPSR and bleeding rates.

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.

Comparison of safety and efficacy of different positions in percutaneous nephrolithotomy: a network meta-analysis

OBJECTIVES

Various new positions for percutaneous nephrolithotomy (PCNL) were proposed to reduce the limitations of the traditional position. This study was aimed to evaluate the efficacy and safety of the different PCNL positions.

METHODS

PubMed, Embase, Web of Science, and the Cochrane Library were searched for relevant randomized controlled trials (RCTs) up to 18 April 2023. The authors collected five common surgical positions used for PCNL: oblique supine position (OSP), supine position (SP), flank position (FP), split-leg oblique supine/flank position (SLP), and prone position (PP). Paired and network meta-analysis were conducted to compare relevant outcomes, including complications, operative time, stone-free rates, hospital stay, and hemoglobin loss among these different positions.

RESULTS

The study included 17 RCTs with a total of 1841 patients. The result demonstrated that SLP significantly outperformed in terms of decreasing operation time (FP vs SLP MD- MD-41.65; OSP vs SLP MD 28.97; PP vs SLP MD 34.94), hospital stay, and hemoglobin loss. Ranking probabilities showed SLP had highest stone-free rate. Prone position was more likely to occur complications than others. Based on SMAA model, the benefit-risk analysis suggested the SLP was the optimal position in PCNL.

CONCLUSIONS

For PCNL, the split-leg, flank, supine, and OSPs are as secure as the prone position. Further RCTs are necessary to confirm the outstanding safety and efficacy of split-leg position. Besides, the position should be selected regard for the patient's demands, the surgeon's preference and learning curve.

Has fluoroless endourology (URS and PCNL) come of age? Evidence from a comprehensive literature review

INTRODUCTION

Radiation via the use of imaging is a key tool in management of kidney stones. Simple measures are largely taken by the endourologists to implement the 'As Low As Reasonably Achievable' (ALARA) principle, including the use of fluoroless technique. We performed a scoping literature review to investigate the success and safety of fluoroless ureteroscopy (URS) or percutaneous nephrolithotomy (PCNL) procedures for the treatment of KSD.

METHODS

A literature review was performed searching bibliographic databases PubMed, EMBASE and Cochrane library, and 14 full papers were included in the review in accordance with the PRISMA guidelines.

RESULTS

Of the 2535 total procedures analysed, 823 were fluoroless URS vs. 556 fluoroscopic URS; and 734 fluoroless PCNL vs. 277 fluoroscopic PCNL. The SFR for fluoroless vs. fluoroscopic guided URS was 85.3% and 77%, respectively (p=0.2), while for fluoroless PCNL vs. fluoroscopic group was 83.8% and 84.6%, respectively (p=0.9). The overall Clavien-Dindo I/II and III/IV complications for fluoroless and fluoroscopic guided procedures were 3.1% (n=71) and 8.5% (n=131), and 1.7% (n=23) and 3% (n=47) respectively. Only 5 studies reported a failure of the fluoroscopic approach with a total of 30 (1.3%) failed procedures.

CONCLUSION

The ALARA protocol has been implemented in endourology in numerous ways to protect both patients and healthcare workers during recent years. Fluoroless procedures for treatment of KSD are safe and effective with outcomes comparable to standard procedures and could become the new frontier of endourology in selected cases.

Comparison of Treatment Outcomes for Fluoroscopic and Fluoroscopy-free Endourological Procedures: A Systematic Review on Behalf of the European Association of Urology Urolithiasis Guidelines Panel

CONTEXT

Endourological procedures frequently require fluoroscopic guidance, which results in harmful radiation exposure to patients and staff. One clinician-controlled method for decreasing exposure to ionising radiation in patients with urolithiasis is to avoid the use of intraoperative fluoroscopy during stone intervention procedures.

OBJECTIVE

To comparatively assess the benefits and risks of "fluoroscopy-free" and fluoroscopic endourological interventions in patients with urolithiasis.

EVIDENCE ACQUISITION

A systematic review of the literature from 1970 to 2022 was performed using the MEDLINE/PubMed, Embase, and Cochrane controlled trials databases and ClinicalTrials.gov. Primary outcomes assessed were complications and the stone-free rate (SFR). Studies reporting data on ureteroscopy and percutaneous nephrolithotomy (PCNL) were eligible for inclusion. Secondary outcomes were operative duration, hospital length of stay, conversion from a fluoroscopy-free to a fluoroscopic procedure, and requirement for an auxiliary procedure to achieve stone clearance.

EVIDENCE SYNTHESIS

In total, 24 studies (12 randomised and 12 observational) out of 834 abstracts screened were eligible for analysis. There were 4564 patients with urolithiasis in total, of whom 2309 underwent a fluoroscopy-free procedure and 2255 underwent a comparative fluoroscopic procedure for treatment of urolithiasis. Pooled analysis of all procedures revealed no significant difference between the groups in SFR (p = 0.84), operative duration (p = 0.11), or length of stay (p = 0.13). Complication rates were significantly higher in the fluoroscopy group (p = 0.009). The incidence of conversion from a fluoroscopy-free to a fluoroscopic procedure was 2.84%. Similar results were noted in subanalyses for ureteroscopy (n = 2647) and PCNL (n = 1917). When only randomised studies were analysed (n = 12), the overall complication rate was significantly in the fluoroscopy group (p < 0.001).

CONCLUSIONS

For carefully selected patients with urolithiasis, fluoroscopy-free and fluoroscopic endourological procedures have comparable stone-free and complication rates when performed by experienced urologists. In addition, the conversion rate from a fluoroscopy-free to a fluoroscopic endourological procedure is low at 2.84%. These findings are important for clinicians and patients, as the detrimental health effects of ionising radiation are negated with fluoroscopy-free procedures.

PATIENT SUMMARY

We compared treatments for kidney stones with and without the use of radiation. We found that kidney stone procedures without the use of radiation can be safely performed by experienced urologists in patients with normal kidney anatomy. These findings are important, as they indicate that the harmful effects of radiation can be avoided during kidney stone surgery.

2022 Recommendations of the AFU Lithiasis Committee: Percutaneous nephrolithotomy

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

Ultrasound-guided percutaneous nephrolithotomy (PCNL) success rates in patients with elevated body mass index: a comparative study

Percutaneous nephrolithotomy (PCNL) is considered gold standard treatment of renal stones larger than 20 mm. Several studies have shown that ultrasound guidance during this procedure is more effective and safer than fluoroscopy. A higher body mass index (BMI) can make ultrasound-guided renal access more difficult and unsuccessful. We present a prospective analysis and comparison of ultrasound-guided PCNL in patients with normal and increased body mass index. We performed a prospective comparison of patients who underwent ultrasound-guided PCNL to remove renal stones by a single surgeon between 2020 and 2022. Patients with BMIs greater than 30 (mean 33.87-obese) were compared to those with BMIs less than 30 (mean 25.69-non-obese). Demographic, perioperative, and follow-up data were collected, analyzed, and included in this study. Total of 98 consecutive patients, with 49 patients in each group were analyzed. No statistically significant differences were observed in terms of stone volume (P = 0.085), stone density (P = 0.5590), location of renal access (P = 0.108), surgery duration (P = 0.38), blood loss (P = 0.54), or laboratory changes after surgery (P = 0.60). 87.76% of obese patients were stone free per CT scan at follow-up, compared to 73.47% of normal-weight patients (P = 0.1238). According to Clavien-Dindo classification, six patients in the non-obese group experienced grade II (10%) and grade III (2%) complications, as opposed to six patients in the obese group with grade I (2%), grade II (6%), and grade III (2%) complications. There was no significant correlation between body mass index and the success or safety of ultrasound-guided PCNL. Although more challenging, a higher BMI should not be an impediment to performing this approach. This method is safe, with no increased incidence of postoperative complications or compromise in stone-free status postoperatively and can diminish or avoid both patient's and medical team's exposure to ionizing radiation.

Best Practice in Interventional Management of Urolithiasis: An Update from the European Association of Urology Guidelines Panel for Urolithiasis 2022

PURPOSE

The European Association of Urology (EAU) has updated its guidelines on clinical best practice in urolithiasis for 2021. We therefore aimed to present a summary of best clinical practice in surgical intervention for patients with upper tract urolithiasis.

MATERIALS AND METHODS

The panel performed a comprehensive literature review of novel data up to May 2021. The guidelines were updated and a strength rating was given for each recommendation, graded using the modified Grading of Recommendations, Assessment, Development, and Evaluations methodology.

RESULTS

The choice of surgical intervention depends on stone characteristics, patient anatomy, comorbidities, and choice. For shockwave lithotripsy (SWL), the optimal shock frequency is 1.0-1.5 Hz. For ureteroscopy (URS), a postoperative stent is not needed in uncomplicated cases. Flexible URS is an alternative if percutaneous nephrolithotomy (PCNL) or SWL is contraindicated, even for stones >2 cm. For PCNL, prone and supine approaches are equally safe. For uncomplicated PCNL cases, a nephrostomy tube after PCNL is not necessary. Radiation exposure for endourological procedures should follow the as low as reasonably achievable principles.

CONCLUSIONS

This is a summary of the EAU urolithiasis guidelines on best clinical practice in interventional management of urolithiasis. The full guideline is available at https://uroweb.org/guidelines/urolithiasis.

PATIENT SUMMARY

The European Association of Urology has produced guidelines on the best management of kidney stones, which are summarised in this paper. Kidney stone disease is a common condition; computed tomography (CT) is increasingly used to diagnose it. The guidelines aim to decrease radiation exposure to patients by minimising the use of x-rays and CT scans. We detail specific advice around the common operations for kidney stones.

Can trajectory nor-epinephrine infiltration reduce blood loss during percutaneous nephrolithotomy? A double-blinded randomized controlled trial

PURPOSE

To determine the efficacy and safety of trajectory infiltration with 1:150 000 Norepinephrine (NE) in reducing blood loss during percutaneous nephrolithotomy (PCNL).

MATERIALS AND METHODS

This is a prospective randomized double-blinded placebo-controlled trial. In all, 140 consecutive patients underwent PCNL for the management of large renal calculi. They were randomly assigned (1:1) to one of either study groups, the NE-PCNL group (70 patients whose PCNL-trajectory was infiltrated by NE) or the Placebo group (saline PCNL) (70 patients whose PCNL tracts were infiltrated by normal saline). Procedure-related blood loss (the primary outcome) was assessed and statistically analyzed. Also, all other procedure-related events and complications were recorded and compared.

RESULTS

The median blood loss was 378 ml (IQR: 252-504) in the NE-PCNL group versus 592 ml (IQR: 378-756) in the S-PCNL group (p < 0.0001). In addition, Hemoglobin and Hematocrit deficits were lower in NE-PCNL (p < 0.05). Patients who were randomized to the NE-PCNL group had a higher immediate stone-free rate (SFR) (80%) compared with those of the S-PCNL group (70%) (p = 0.034). However, no statistical differences were found in the final SFR. The reported overall complications between the 2 groups were similar (p > 0.05). Indeed, bleeding-related complications were 1 (1.4%) versus 10 (14.3%) for NE-PCNL and S-PCNL, respectively (p = 0.009).

CONCLUSIONS

Trajectory infiltration of PCNL tracts by NE was found to be effective and safe in mitigation of PCNL-related blood loss. This step is a timeless and cost-effective as NE is readily available in surgical theaters and of very low cost.

Percutaneous nephrolithotomy - the puncture

OBJECTIVE

To determine what importance is given to the puncture and assistive technologies in percutaneous nephrolithotomy (PNL) in the current urological literature.

METHODS

PubMed was searched for English publications and reviews for the keywords: 'percutaneous nephrolithotomy', 'percutaneous nephrostomy', 'puncture'. The search was limited to the last 5 years, January 2016 until February 2021. Based on 183 abstracts, 121 publications were selected, read, and reviewed. References, older or seminal papers were read and cited if they contributed to a better understanding. A total of 198 references form the basis of this narrative review.

RESULTS

The puncture is frequently referred to as the most crucial part of PNL. In contrast, the influence of the puncture on the failure rate of PNL and the specific puncture-related complications seems to be low in the single-digit percentage range. However, there are no universally accepted definitions and standards measuring the quality of puncture. Consequently, the impact of the puncture on general PNL complications, on stone scores predicting success rates and on learning curves evaluating surgeons' performance have not been systematically studied. Assistive technologies rely on fluoroscopy and ultrasonography, the latter of which is becoming the preferred imaging modality for monitoring the entire procedure. Needle bending, a problem relevant to all puncture techniques, is not addressed in the urological literature.

CONCLUSIONS

The importance attached to puncture in PNL in the current urological literature is subjectively high but objectively low. Some basics of puncture are not well understood in urology. Disciplines other than urology are more actively involved in the development of puncture techniques.

Evaluating outcomes of complete supine percutaneous nephrolithotomy for staghorn vs multiple non-staghorn renal stones: a 10-year study

PURPOSE

To evaluate the outcomes of complete supine percutaneous nephrolithotomy (csPCNL) for staghorn stones and multiple large non-staghorn stones.

METHODS

The records of 886 patients who underwent csPCNL from September 2009 to October 2019 were considered. Out of them, 201 cases met the eligibility criteria and they were divided into three groups: 63 cases of staghorn, 68 cases of multiple medium (20 mm < diameter ≤ 30 mm) non-staghorn and 70 cases of multiple large non-staghorn (> 30 mm) stones. Almost all outcomes and stone-related factors were analyzed.

RESULTS

There was not any significant difference regarding age, body mass index, history of urinary tract infection, transfusion rate, complication rate, pre and post-surgery serum creatinine, hemoglobin drop and total hospital stay between the three groups. Stone free rate was 98.5% in multiple medium group, 97.1% in multiple large group and 84.1% in staghorn group (P = 0.001). The operation duration was significantly shorter for the multiple medium group (P < 0.001) but it was not significantly different between the multiple large non-staghorn and staghorn group.

CONCLUSION

The results demonstrated that almost all outcomes were not significantly different between the three groups (especially between staghorn and larger non-staghorn ones). These findings reveal that surgeons could choose csPCNL for treatment of staghorn stones and multiple large non-staghorn stones and consider staghorn stones as challenging as multiple large (especially diameter > 30 mm) non-staghorn stones.

A study on comparative outcomes of totally ultrasonography-guided percutaneous nephrolithotomy in prone versus flank position: a randomized clinical trial

PURPOSE

The percutaneous nephrolithotomy (PCNL) has become the gold-standard for treating patients with the larger renal stones and staghorn calculi. This study was designed to evaluate the outcomes of flank versus prone position in patients underwent ultrasonic-guided PCNL for treatment of large kidney stones.

METHODS

This prospective randomized clinical trial was conducted from September 2017 to September 2019 in the department of Urology, Labbafinejad University hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran. Two hundred patients with kidney stones larger than 2 cm underwent PCNLs in prone (n = 100) or flank position (n = 100). Success rate, operative time, access time, hemoglobin and creatinine changes, hospital stay, auxiliary procedure and surgical complications were compared between the two groups.

RESULTS

The two groups were similar in their baseline characteristics. The success rates in prone (87%) versus flank position (85%) were not significantly different at the first post-operative follow-up (p = 0.91). At the three-month follow-up, the overall stone free rates for the prone position PCNLs and flank position PCNLs were 94/100 (94%) and 90/100 (90%) (p = 0.96). There were no significant difference between the groups in operative time (p = 0.42), access time (p = 0.66), hemoglobin (p = 0.46) and creatinine (p = 0.22) changes, hospital stay (p = 0.05), auxiliary procedures (p = 0.75) and surgical complications.

CONCLUSION

Overall, there is no significant difference between prone and flank positions in success rate and complications. More prospective studies must be carried out to identify patient populations who are most apt to benefit from one position over the other.

TRIAL REGISTRATION NUMBER

IRCT20200902048597N1 DATE OF REGISTRATION: 2020-11-21, retrospectively registered.

Mini-percutaneous Nephrolithotomy Under mixture of Local Anesthesia: A Randomized-Controlled Study

OBJECTIVE

to evaluate the safety, efficacy, and feasibility of mini-percutaneous nephrolithotomy (MPCNL) under mixture of local anesthetics (MLA) versus spinal anesthesia (SA) for management of large renal stones.

PATIENTS AND METHODS

the current study was a prospective randomized controlled study. A total of 120 consecutive patients who met the inclusion criteria of the study and agreed to sign the informed consent form were randomized to undergo MPCNL under MLA (60 patients) or SA (60 patients). Intra- and post-operative findings included visual pain analogue scale (VAS), operative time, hospital stay, adverse events, stone-free rate and related data were recorded.

RESULTS

Baseline characteristics and demography included age, sex; stone's site, size and density were comparable for both groups (p> 0.05). The average VAS scores in MLA group at 0, 2, 6, 12; and 24 hours were 2.5; 0;1; 1 and 0, respectively. The corresponding values in the SA group were 2; 1; 2; 2; and 1, respectively, (p< 0.05). The average operation time was about an hour for both groups and the length of hospital stay was 1.5 days for both groups (p> 0.05). While the mean hemoglobin deficit was 1.04±0.54 % vs 1.27±0.46 (p=0.013), and the primary postoperative stone clearance was 93.4%, vs 88.3% (p > 0.05), for MLA and SA groups, respectively. Post-operative analgesic consumption and Complications were similar in the MLA and SA groups.

CONCLUSION

Single tract MPCNL is feasible under either mixture of Local or Spinal anesthesia with comparable stone clearance & adverse events. Perioperative VAS was similar and acceptable for both modalities.

Minimizing radiation dose in management of stone disease: how to achieve 'ALARA'

PURPOSE OF REVIEW

Exposure to radiation is known to have adverse effects such as secondary malignancies. Patients with nephrolithiasis are exposed to radiation in the workup and treatment of their condition. Furthermore, exposure to radiation is often repeated due to the high recurrence rate of nephrolithiasis.

RECENT FINDINGS

We discuss practices inside and outside of the operating room to strive to keep radiation exposure as low as reasonably achievable (ALARA) for patients being treated for nephrolithiasis. These efforts include reduced dose computed tomography scans, fluoroless surgical techniques and new alternative technologies.

SUMMARY

Maintaining radiation exposure ALARA for our patients is increasingly practical. The urologist must make every effort to adhere to ALARA principles to protect patients from the stochastic effects of radiation.

Ultrasound or Fluoroscopy for Percutaneous Nephrolithotomy Access, Is There Really a Difference? A Review of Literature

Objective: To compare whether the outcomes of ultrasound-guided access percutaneous nephrolithotomy (USGA-PCNL) are similar to standard fluoroscopy-guided access percutaneous nephrolithotomy (FGA-PCNL). Methods: A review was developed by using the MEDLINE and Scopus databases and following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses protocol. Studies comparing the USGA-PCNL and the FGA-PCNL were included. Case reports, editorials and letters, unpublished studies, posters, and comments abstracts were excluded. Results: We found 12 published articles that compared USGA-PCNL and FGA-PCNL. These included six randomized controlled trials, three case-control trials, and three meta-analyses. The overall results showed no difference in the success of percutaneous access, bleeding, blood transfusion, operative time, postoperative complications, or hospital stay. Conclusion: The reported data demonstrate that there are no significant differences between the fluoroscopic-guided access PCNL and the ultrasonographic access PCNL. The choice of puncture depends on the surgeon's expertise in a particular technique and the patient and stone characteristics. Both approaches are equally safe and effective in experienced hands. It is important to recall that the use of one technique does not exclude the use of the other, and they can sometimes be complementary to each other.

Prone versus supine percutaneous nephrolithotomy: a systematic review and meta-analysis of current literature

INTRODUCTION

Percutaneous nephrolithotomy (PNL) can be performed either in prone or supine position. This study aimed at gathering together randomized controlled trials (RCTs) comparing efficacy and safety between prone and supine PNL.

EVIDENCE ACQUISITION

Systematic review of literature was conducted using the Scopus, Medline and Web of Science databases. Study selection, data extraction and quality assessment were independently assessed by two authors. Meta-analysis was performed with Review Manager 5.3. Sensitivity analyses were performed to exclude studies with high risk of bias.

EVIDENCE SYNTHESIS

Pooled data from 12 studies including 1290 patients were available for analysis. Only one study was found to have overall low risk of bias. Significantly shorter operative time was found in favor of supine PNL (mean difference 13 minutes, 95% confidence interval [CI]: 3.4-22.7; P<0.01). Stone-free rate (SFR)≥14 days after surgery was significantly higher in prone PNL (odds ratio [OR]=2.15, 95% CI: 1.07-4.34; P=0.03). Significantly higher fever rate was found in prone PNL (OR=1.60, 95% CI: 1.03-2.47; P=0.04). Overall SFR, hospital stay length, complications rate, transfusions rate and blood loss, as well as non-lower calyx puncture rate, puncture attempts and tubeless intervention rate did not differ between prone and supine PNL (P>0.05).

CONCLUSIONS

Efficacy of PNL seems balanced between prone and supine position, with comparable overall SFR and shorter operative time in favor of supine PNL. Safety of PNL appears in favor of supine PNL, with lower fever rate. Because of study heterogeneity and possible risks of outcome bias, results from this study should be interpreted with caution. Altogether, both prone and supine PNL account for appropriate therapy options.

Supine versus prone position for percutaneous nephrolithotripsy: A meta-analysis of randomized controlled trials

OBJECTIVE

To compare the safety and efficacy of percutaneous nephrolithotripsy (PCNL) in supine versus prone position for patients with renal or upper ureteral calculi.

METHODS

A systematic search of Pubmed, Embase and Cochrane Central Register of Controlled Trials was performed to identify all eligible studies. All included randomized controlled trials (RCTs) were evaluated based on the inclusion and exclusion criteria. After quality assessment and date extraction, a meta-analysis was performed using RevMan 5.3 software.

RESULTS

A total of 15 RCTs with 1474 patients were included in our meta-analysis. Pooled data showed that PCNL in supine position could significantly reduce the operative time [weighted mean difference (WMD) -12.02, 95% confidence interval (CI) -20.49 to -3.54, p = 0.005] and rate of fever [risk ratio (RR) 0.67, 95% CI 0.46 to 0.97, p = 0.03] compared to prone position. In addition, no significant differences could be found between groups in stone-free rate (p = 0.31), hospital stay (p = 0.59) and rate of overall complications (p = 0.11), mainly including urinary leakage (p = 0.83), pleural effusion (p = 0.74) and blood transfusion (p = 0.58).

CONCLUSIONS

The current study found comparable stone-free rate and significant lower rate of postoperative fever in supine PCNL compared with prone PCNL. PCNL in supine position could be a safe and efficient choice for patients with renal or upper ureteral calculi.