Classification of percutaneous nephrolithotomy complications using the modified clavien grading system: looking for a standard

Flexible Ureteroscopy versus Retroperitoneal Laparoscopic Ureterolithotomy for the Treatment of Proximal Ureteral Stones >15 mm: A Single Surgeon Experience

OBJECTIVE

To compare safety and effectiveness of flexible ureteroscopy (F-URS) and laparoscopic retroperitoneal ureterolithotomy (L-RU) in treatment of proximal ureteral stones larger than 15 mm.

MATERIALS AND METHODS

This study included 103 patients treated with L-RU (Group I), and 80 patients treated with F-URS (Group II) due to proximal ureteral stones larger than 1.5 cm, in a single center. Patients' characteristics and procedure-related parameters including success rate, operation time, hospital stay, postoperative visual analogue scale (VAS) scores, auxiliary procedures, and complications were compared between Groups I and II.

RESULTS

It was seen that both methods were effective in the treatment of large ureteral stones; however, R-LU provided a higher stone-free rate (100 vs. 87.5%), a lower complication rate (10.6 vs. 23.7%), and a shorter operation time (65.4 vs. 75.1 min). On the other hand, patients treated with F-URS had less postoperative pain, a shorter hospital stay, a faster return to daily activities.

CONCLUSIONS

For treatment of large proximal ureteral stones, L-RU provides significantly higher success and lower retreatment rate compared with F-URS. Our results also indicate that R-LU, which has been regarded as an invasive procedure is not as invasive as it is thought to be, and it must be kept in mind that F-URS may cause complications despite its noninvasive nature.

Evaluation of stone-free rate using Guy's Stone Score and assessment of complications using modified Clavien grading system for percutaneous nephro-lithotomy

To prospectively evaluate the ability of Guy's Stone Score (GSS) in predicting stone clearance rate and complication rate (by modified Clavien grade) for renal stones treated by percutaneous nephrolithotomy (PNL). From January 2013 to June 2014, a total of 142 patients undergoing PNL were evaluated prospectively. Patients with co-morbidities like hypertension, diabetes, renal failure were excluded from the study. All patients were classified according to GSS based on the findings of pre-operative intravenous urography (IVU) and per-operative retrograde pyelography (RGP). All PNL procedures were done by standard technique in prone position and success was defined as no residual stone visible on X-ray KUB done on the third postoperative day. Complications were classified according to modified Clavien grading system. The initial stone clearance rate was 71.1% and overall final stone clearance rate was 90.14%. The complication rate according to Clavien grading system was 40.1%. The final stone clearance rates were 93.9, 85.71, 90.47, and 77.77% in GSS I, II, III, and IV, respectively (p<0.001, <0.05, <0.05 and >0.05, respectively). The Clavien complication rates were 23, 61, 52, and 77.7% in GSS I, II, III, and IV, respectively (p<0.001). The GSS is a simple and easily reproducible system to preoperatively predict stone-free rate and perioperative complication rate. It helps in better patient counseling preoperatively.

Mini percutaneous nephrolithotomy in the treatment of renal and upper ureteral stones: Lessons learned from a review of the literature

The aim of this review is to present the most recent data regarding the indications of mini percutaneous nephrolithotomy (PCNL), the results and the complications of the method. Medline was searched from 1997 to January 2014, restricted to English language. The Medline search used a strategy including medical subject headings and free-text protocols. PCNL is a well-established treatment option for patients with large and complex renal calculi. In order to decrease morbidity associated with larger instruments like blood loss, postoperative pain and potential renal damage, a modification of the technique of standard PCNL has been developed. This is performed with a miniature endoscope via a small percutaneous tract (11–20 F) and was named as minimally invasive or mini-PCNL. This method was initially described as an alternative percutaneous approach to large renal stones in a pediatric patient population. Furthermore, it has become a treatment option for adults as well, and it is used as a treatment for calculi of various sizes and locations. However, the terminology has not been standardized yet, and the procedure lacks a clear definition. Nevertheless, mini-PCNL can achieve comparable stone-free rates to the conventional method, even for large stones. It is a safe procedure, and no major complications are reported. Although less invasiveness has not been clearly demonstrated so far, mini-PCNL is usually related to less blood loss and shorter hospital stay than the standard method.

The comprehensive complication index: a novel and more sensitive endpoint for assessing outcome and reducing sample size in randomized controlled trials

OBJECTIVE

To test whether the newly developed comprehensive complication index (CCI) is more sensitive than traditional endpoints for detecting between-group differences in randomized controlled trials (RCTs).

BACKGROUND

A major challenge in RCTs is the choice of optimal endpoints to detect treatment effects. Mortality is no longer a sufficient marker in studies, and morbidity is often poorly defined. The CCI, integrating all complications including their severity in a linear scale ranging from 0 (no complication) to 100 (death), is a new tool, which may be more sensitive than other traditional endpoints to detect treatment effects on postoperative morbidity.

METHODS

The CCI was tested in 3 published RCTs from European centers evaluating pancreas, esophageal and colon resections. To compare the sensitivity of the CCI with traditional morbidity endpoints, for example, presence of any (yes/no) or only the most severe complications, all postoperative events were assessed, and the CCI calculated. Treatment effects and sample size calculations were compared using the CCI and traditional endpoints.

RESULTS

Although RCTs failed to show between-group differences using any or most severe complications, the CCI revealed significant differences between treatment groups in 2 RCTs-after pancreas (P=0.009) and esophageal surgery (P=0.014). The CCI in the RCT on colon resections confirmed the absence of between-group differences (P=0.39). The required sample sizes in trials are up to 9 times lower for the CCI than for traditional morbidity endpoints.

CONCLUSIONS

This study demonstrates superiority of the CCI to traditional endpoints. The CCI may serve as an appealing endpoint for future RCTs and may reduce the sample size.

Flank-free Modified Supine Percutaneous Nephrolithotomy in Pediatric Age Group

OBJECTIVE

To evaluate the safety and efficacy of pediatric percutaneous nephrolithotomy (PCNL) in the flank-free modified supine position (FFMSP). PCNL in the supine position is increasingly and successfully used in pediatric age group. Different modifications of supine positions have been described; however, the best supine position is not well established and remains a matter of debate.

PATIENTS AND METHODS

This prospective study included 22 children presenting with single renal pelvis stone (2-3 cm) in the period between May 2012 and April 2014. Diagnosis was set by plain x-ray and computed tomography in all patients. PCNL was performed with the patients placed in the FFMSP. The operative time and hospital stay were estimated. The outcome and any perioperative complications or conflicts were recorded.

RESULTS

The study included 22 children (15 boys and 7 girls) with a solitary renal pelvis stone. Mean ± standard deviation age of the patients was 9.5 ± 3.2 years (range, 3-15.5 years). Stone length, operative time, and hospital stay had mean ± standard deviation of 2.4 ± 0.23 cm, 65.1 ± 18.7 minutes, and 4.4 ± 0.9 days. Stone-free rate was 90.9% after 1 session of PCNL. One patient (4.5%) needed a second-look PCNL. Shock wave lithotripsy was performed for another patient. Postoperative fever occurred in 4 patients (18.2%). One patient received postoperative blood transfusion. Postoperative transient urinoma occurred in 2 patients (9.1%).

CONCLUSION

PCNL in pediatric age group via FFMSP was proved to be safe and effective in management of renal pelvis stones of size 2-3 cm. It provides stone clearance rate comparable with that reported of conventional PCNL in the prone position.

Factors affecting complications according to the modified Clavien classification in complete supine percutaneous nephrolithotomy

INTRODUCTION

An increase in percutaneous nephrolithotomy (PCNL) has been accompanied by an increase in complications. We identified the parameters affecting the severity of complications using the modified Clavien classification (MCC).

METHODS

From 2008 to 2013, 330 patients underwent complete supine PCNL using subcostal access, one-shot dilation, rigid nephroscopy, and pneumatic lithotripsy. We assessed the impact of the following factors on complication severity based on the MCC: age, gender, body mass index, hypertension, diabetes, previous stone surgery and extracorporeal shock wave lithotripsy, preoperative hemoglobin, renal dysfunction (creatinine >1.4 mg/dL), preoperative urinary tract infection, anatomic upper urinary tract abnormality (AUUTA), significant (moderate-severe) hydronephrosis, stone-related parameters (opacity, number, burden, location, staghorn, complex stones), anesthesia type, kidney side, imaging and calyx for access, tract number, tubeless approach, operative time, postoperative hemoglobin, and hemoglobin drop and stone-free results.

RESULTS

The complication rate was 19.7% (MCC: 0=80.3%, I=6.4%, II=11.2%, ≥III=2.1%). On univariate analyses, only the following factors affected MCC: gender, preoperative hemoglobin, AUUTA, significant hydronephrosis, imaging for access, calyx for access, tract number, postoperative hemoglobin, hemoglobin drop and stone-free result. Renal dysfunction was accompanied by higher complications, yet the results were not statistically significant. Multivariate logistic regression analysis demonstrated renal dysfunction, absence of significant hydronephrosis, AUUTA, multiple tracts, lower postoperative hemoglobin, and higher postoperative hemoglobin drop as the significant parameters which affected MCC and predicted higher grades. The paper's limitations include a low number of cases in the higher Clavien grades and some subgroups of variables, and not applying some techniques due to surgeon preference.

INTERPRETATION

Many of the complete supine PCNL complications were in the lower Clavien grades and major complications were uncommon. Renal dysfunction, AUUTA, significant hydronephrosis, tract number, postoperative hemoglobin, and hemoglobin drop were the only factors affecting MCC.

Comparison of complications associated with standard and totally tubeless percutaneous nephrolithotomy according to modified Clavien grading: a multicenter retrospective study

The aim of this study was to compare the complications of standard and totally tubeless percutaneous nephrolithotomy (PCNL) based on the modified Clavien complication grading system. We retrospectively evaluated the complications of 290 consecutive patients who had undergone standard or totally tubeless PCNL at four institutes between January 2010 and August 2012 based on the modified Clavien scale. The totally tubeless cases were classified as Group 1 and the cases to which a Malecot re-entry catheter was applied were classified as Group 2. The postoperative complications were recorded according to the modified Clavien complication grading system. Statistically significant differences were observed only in the first-degree injury class between the two groups based on the modified Clavien classification. The requirement for blood transfusion and prolonged percutaneous access site leakage were more frequent in Group 2, but these differences were not statistically significant. We also performed a pain evaluation by monitoring postoperative analgesia demands. In Group 1, the analgesic demand rates in the 1(st) and 6(th) postoperative hours were 64.6% and 31.5%, respectively. In Group 2, the analgesic demand rates were 87.5% and 58.75% in the 1(st) and 6(th) postoperative hours, respectively. The mean ± standard deviation of analgesic doses in the first 6 hours was 0.96 ± 0.7 and 1.46 ± 0.6 in Groups 1 and 2, respectively. These differences were statistically significant. Based on our results, we can conclude that the tubeless technique has fewer complications, improved postoperative patient comfort, shorter hospitalization times, and a reduced need for analgesics, suggesting that tubeless PCNL should be the standard approach. For suitable cases, this technique may be used safely as the standard PCNL approach.

Complications in percutaneous nephrolithotomy

Percutaneous nephrolithotomy (PCNL) is generally considered a safe technique offering the highest stone-free rates after the first treatment as compared to the other minimal invasive lithotripsy techniques. Still, serious complications although rare should be expected following this percutaneous procedure. In this work, the most common and important complications associated with PCNL are being reviewed focusing on the perioperative risk factors, current management, and preventing measures that need to be taken to reduce their incidence. In addition, complication reporting is being criticized given the absence of a universal consensus on PCNL complications description. Complications such as perioperative bleeding, urine leak from nephrocutaneous fistula, pelvicalyceal system injury, and pain are individually graded as complications by various authors and are responsible for a significant variation in the reported overall PCNL complication rate, rendering comparison of morbidity between studies almost impossible. Due to the latter, a universally accepted grading system specialized for the assessment of PCNL-related complications and standardized for each variation of PCNL technique is deemed necessary.

Laparoscopic versus open orchiopexy in the management of peeping testis: a multi-institutional prospective randomized study

OBJECTIVE

Peeping testis is an inconsistently palpable/seen undescended testis that migrates back and forth at the internal inguinal ring. Both open and laparoscopic orchiopexy are effective forms of management. The present study aimed to evaluate the efficacy and safety of both approaches.

PATIENTS AND METHODS

Between September 2007 and January 2012, 46 peeping inguinal testes were randomly treated with either open (25 cases) or laparoscopic (21 cases) orchiopexy procedures. Spermatic vessels were preserved for all cases. Operative details, postoperative morbidity and final testicular site and size were recorded.

RESULTS

The median age of the children was 2.5 years (range 0.5-12.0). The follow-up period ranged from 1.0 to 5.5 years. Of these testes, 20 in the open surgery group and 19 in the laparoscopic group maintained correct intrascrotal position (P = 0.428). Re-do orchiopexy was indicated for two cases in the surgical group (P = 0.493). No cases of testicular atrophy or hernia were encountered.

CONCLUSION

Open and laparoscopic orchiopexy procedures for peeping testes are fairly comparable. However, laparoscopy is relatively more effective, as two re-do orchiopexies were required in the open surgical group.

Endoscopic guided additional access for staghorn calculi

BACKGROUND AND PURPOSE

Flexible nephroscopy is an important technique in the management of staghorn renal calculi to reach peripheral calices. In this study, we present our experience with flexible nephroscopy and fluoroscopy-guided additional access creation for staghorn renal calculi.

PATIENTS AND METHODS

We conducted a retrospective analysis of patients with staghorn renal calculi who were treated with multiple percutaneous renal tracts created with the guidance of flexible nephroscopy and fluoroscopy. Additional tracts were performed with combined flexible nephroscopy and fluoroscopy guidance. Flexible nephroscopy was used to help target the calix and ensure the safety of access.

RESULTS

Additional percutaneous renal access was achieved using combined flexible nephroscopy and fluoroscopy guidance in 26 patients with complete staghorn (n=21) and partial staghorn (n=5) kidney stones. The cumulative stone size was 59.3 mm. The mean procedure times, fluoroscopy times, and hospitalization times were 91.5 minutes, 3.4 minutes, and 2.7 days, respectively. The postoperative hematocrit drop was 4.96±3.8. Upper and lower calices were the most common primary access tracts in 11 and 15 patients, respectively. Stone-free status was achieved in 22 (84.6%) patients with a mean 2.1±0.3 tract number. Postoperative complications were observed in six (23.1%) patients.

CONCLUSIONS

In the requirement of additional access for staghorn renal calculi, use of flexible nephroscopy with fluoroscopy increases the safety of the procedure by confirmation of precise renal access.

Minimally invasive percutaneous nephrolithotomy for simple and complex renal caliceal stones: a comparative analysis of more than 10,000 cases

PURPOSE

To determine whether minimally invasive PCNL (MPCNL) is as safe and effective in the management of complex renal caliceal stones as it is for simple renal stones.

PATIENTS AND METHODS

We retrospectively reviewed 5761(41.2%) simple caliceal stones (isolated renal pelvis including isolated calix) and 8223 (58.8%) complex caliceal stones (renal pelvis accompanying two calices at least) that were managed by MPCNL between 1992 nd 2011. The safety, efficacy, and outcome were compared and analyzed.

RESULTS

Stone burden was larger in complex caliceal stones (1763.0 vs 1018.6 mm(2), P<0.05). Patients with simple stones had significantly shorter operative time, less frequency of multiple percutaneous accesses, and less hemoglobin drop. They also had a higher initial stone-free rate (SFR) (77.6% vs 66.4%) after a single session of MPCNL (P<0.05). The differences diminished in the final SFR (86.7% vs 86.1%) after relook and/or auxiliary procedures (P>0.05). The complication rate (17.9% vs 19.0%) and blood transfusion rate (grade II) (2.2% vs 3.2%) were similar in both groups (P>0.05). Both groups had a low rate of high Clavien grade complications. Renal vascular embolizations (grade III), however, were significantly higher in patients with complex caliceal stones (P<0.05).

CONCLUSIONS

MPCNL is a safe and effective treatment option for patients with complex caliceal stones except there is a slightly higher frequency rate of embolization. There was a higher initial SFR in simple stones, but this difference diminished with secondary procedures.

Injury of the ileum during percutaneous nephrolithotomy in a pediatric patient

Ileum injury during percutaneous nephrolithotomy (PCNL) is an extremely rare complication. We describe the successful management of an inadvertently injured ileum during subcostal PCNL in a 12-year-old boy. Mechanism of injury, presentation and management will be discussed.

Factors Influencing the Duration of Urine Leakage following Percutaneous Nephrolithotomy

Purpose. The duration of urine leakage following the removal of the nephrostomy tube after percutaneous nephrolithotomy (PCNL) shows significant variations depending on the techniques used. We aimed to assess the factors likely to influence the duration of urine leakage. Material and Methods. In total, 103 patients who underwent PCNL were reviewed retrospectively. DUL was evaluated regarding patient characteristics, thickness of the access line, presence of hydronephrosis, and residual stones. Results. DUL was significantly prolonged in accordance with a decrease in the thickness of parenchyma tissue (R = −0.716, P < 0.001). DUL was prolonged as the degree of hydronephrosis (R = 0.526, P < 0.001) and the number of patients with residual stones (R = 0.273, P = 0.005) increased. Median DUL was significantly longer in patients with residual stones than those without residual stones (P = 0.002). In the receiving operating curve analysis, the optimum cut-off value of parenchymal thickness for hospitalization ≤12 h was 17.2 mm (sensitivity, 90.2%; specificity, 69.4%; P = 0.001). Conclusions. We found that parenchymal thickness of the access line, hydronephrosis, and residual stones were the most influential factors determining DUL following PCNL, respectively.

Long-term functional outcome of percutaneous nephrolithotomy in solitary kidney

OBJECTIVE

To evaluate the long-term functional outcome of percutaneous nephrolithotomy (PNL) for calculi in solitary kidneys and to determine factors leading to renal function deterioration.

MATERIALS AND METHODS

The computerized files of patients with solitary kidneys who underwent PNL between January 2002 and December 2009 were retrospectively reviewed. Patients with follow-up <2 years were excluded. Complications, secondary procedures, and stone-free rates were recorded. Changes in the renal function were judged by comparing preoperative and postoperative estimated glomerular filtration rates. Preoperative, intraoperative, and postoperative factors that may affect renal function were tested using univariate and multivariate analyses to define risk factors for deterioration of renal function on long-term follow-up.

RESULTS

The study included 200 patients (133 men [66.5%] and 67 women [33.5%] with mean age 52.3 ± 11.7 years). Complications were reported in 34 patients (17%). Severe bleeding was noticed in 10 patients (5%). The overall stone-free rate was 89.5%. After a mean follow-up of 3 ± 1.4 years (range, 2-8), there was significant improvement of the estimated glomerular filtration rate from 57 to 64 mL/min (P <.001). Thirty-one patients (15.5%) showed deterioration of the renal function. Multiple punctures and postoperative bleeding were independent risk factors for renal function deterioration (odds ratio was 3.7 and 4.5, respectively).

CONCLUSION

PNL for calculi in solitary kidneys provided significant improvement in renal function at long-term follow-up. Multiple punctures and severe bleeding are independent risk factors for deterioration of the kidney function.

Comparison of intrarenal pelvic pressure during micro-percutaneous nephrolithotomy and conventional percutaneous nephrolithotomy

The micro-percutaneous nephrolithotomy (microperc) is a recently introduced percutaneous nephrolithotomy (PNL) technique that is performed through a 4.8 Fr all-seeing needle. We aimed to measure the intrarenal pelvic pressure (IPP) during microperc and compare it with the levels of conventional PNL. A total of 20 patients with 1- to 3-cm renal calculi resistant to shock wave lithotripsy were treated either with microperc (Group-1, n: 10) or conventional PNL (Group-2, n: 10) by the same surgical team. The IPP was measured during different stages (entrance into the collecting system, stone fragmentation, and before termination) of the procedures by an urodynamic machine using the 6 Fr ureteral catheter. All the variables were statistically compared between the two groups. The demographic values of the patients were similar. The operation time and duration of hospitalization were significantly prolonged in conventional PNL group (p = 0.034, p = 0.01, respectively). The mean drop in hematocrit levels was significantly lower in microperc group (3.5 ± 1.5 vs. 1.8 ± 0.8; p = 0.004). The IPP was significantly higher in microperc group during all steps of the procedure. The highest level of the IPP was measured as 30.3 ± 3.9 and 20.1 ± 3.1 mmHg in Group 1 and Group 2, respectively (p < 0.0001). However, the complication and success rates were found comparable. In conclusion, we demonstrate that the level of IPP is significantly increased during microperc compared to conventional PNL. Microperc should be used cautiously in cases with impaired drainage of the collecting system.

Managing caliceal stones

The natural course of untreated asymptomatic caliceal calculi has not been clearly defined, especially in terms of disease progression, and the indications for and outcomes of surgical intervention are not precise. Caliceal stones may remain asymptomatic but, in case of migration, ureteral calculi can cause acute ureteric colic with severe complications. The decision for an active treatment of caliceal calculi is based on stone composition, stone size and symptoms. Extracorporal shock-wave lithotripsy (ESWL) has a low complication rate and is recommended by the current guidelines of the European Association of Urology as a first-line therapy for the treatment of caliceal stones <2 cm in diameter. However, immediate stone removal is not achieved with ESWL. The primary stone-free rates (SFR) after ESWL depend on stone site and composition and, especially for lower pole calculi, the SFR differ widely from other caliceal stones. Minimally-invasive procedures including percutaneous nephrolithotomy and ureteroscopy are alternatives for the treatment of caliceal stones, associated with low morbidity and high primary SFR when performed in centers of excellence.

Standardizing the reporting of percutaneous nephrolithotomy complications

Accurate reporting of complications is an essential component to critical appraisal and innovation in surgery and specifically with percutaneous nephrolithotomy (PCNL). We review the evolution of complication reporting for PCNL and suggest future directions for innovation. A selective review was carried out using Pubmed. Key search terms and their combinations included percutaneous, anatrophic, nephrolithotomy, PCNL, complications, Clavien, Martin score, bleeding, bowel injury, perforation, fever, sepsis. The references from relevant papers and reviews as well as AUA and EAU guidelines were also scanned for inclusion. PCNL has become the procedure of choice for large renal stones owing to decreased morbidity over alternative procedures. Both common and rare complications have been described in large case series, small randomized controlled trials, and case reports in an unstandardized form. Although these reports have provided an informative starting point, a standardized complication reporting methodology is necessary to enable appropriate comparisons between institutions, time periods, or innovations in technique. The Clavien-Dindo grading system has become widely accepted in urology and has facilitated the study of PCNL complications. Future research should focus on adaptions of this system to render it more comprehensive and applicable to PCNL.

Skin-to-stone distance has no impact on outcomes of percutaneous nephrolithotomy

OBJECTIVE

Skin-to-stone distance (SSD) is a stronger factor than body mass index in predicting the success of shock wave lithotripsy. We aimed to evaluate the impact of SSD on outcomes of percutaneous nephrolithotomy (PCNL).

MATERIALS AND METHODS

The medical records of 1,280 patients who had undergone PCNL between April 2007 and February 2012 were evaluated retrospectively. 192 patients who had had preoperative non-contrasted computed tomography and single renal access were included the study. According to this median SSD value, patients were divided into two groups: group 1 (SSD ≤94 mm) (n = 92) and group 2 (SSD >94 mm) (n = 90). The groups were compared according to operative and postoperative parameters.

RESULTS

We found no significant differences between the two groups with regard to stone-free rate, operation time, fluoroscopy time, hospitalization time, visual analog score of pain, stone burden, transfusion rates and complication rates. On the other hand, the mean body mass index of group 1 was significantly lower than that of group 2 (p < 0.05).

CONCLUSIONS

In this retrospective review of patients undergoing PCNL, we found that SSD has no impact on operative and postoperative outcomes. These results were in accordance with the safety of PCNL in obese patients.

A better way to manage perinephric abscesses: percutaneous ultrasonography-guided endoscopic lavage

PURPOSE

To report the efficacy and safety of percutaneous ultrasonography-guided endoscopic lavage in the management of perinephric abscesses.

PATIENTS AND METHODS

This is a retrospective review of patients in a single center who had perinephric abscesses and were treated by percutaneous ultrasonography-guided endoscopic lavage during the period of March 2001 to March 2013. Information including the demographics, comorbid medical conditions, presenting symptoms, size of abscesses, operation information, and postoperative information were retrieved for review.

RESULTS

There were 37 patients (40 operations) identified during the study period. The mean age was 56.8 years (21-91 years). Eighteen (48.9%) patients presented with loin pain (48.6%) and/or fever (18, 48.6%), and the mean diameter of the abscesses was 10.8 cm (5-22 cm). Thirty-one (77.5%) procedures were performed under general anesthesia. The mean operative time was 49.4 minutes (15-140 min). Thirty-one (77.5%) patients had their percutaneous track dilated to 32F. Only two of 37 (5.4%) patients needed repeated drainage. The average postoperative drainage time was 8.35 days (3-21 days). The median postoperative hospital stay for our patients was 10 days (4-101 days). There was no mortality related to the abscess in this cohort.

CONCLUSION

Percutaneous Ultrasonography-guided endoscopic lavage was shown to be an effective and safe approach for patients with perinephric abscesses.

Combination of debulking single-tract percutaneous nephrolithotomy followed by retrograde intrarenal surgery for staghorn stones in solitary kidneys

OBJECTIVE

The aim of this study was to report a therapeutic approach comprising a combination of debulking single-tract percutaneous nephrolithotomy (PCNL) and subsequent retrograde intrarenal surgery (RIRS) for treatment of staghorn stones in patients with solitary kidney.

MATERIALS AND METHODS

A retrospective review was undertaken of 56 patients with staghorn stones in a solitary kidney who underwent the above-mentioned combination therapy. PCNL was first performed for stone debulking and RIRS was then used to remove residual stones after an interval of 2-4 days. Data were collected on operative parameters, stone-free rate (SFR), complications and renal functions.

RESULTS

The staghorn stones had a mean stone burden of 2548 ± 1028 mm(2) (range 1438-3956 mm(2)). The SFR after 3 months was 89.3%. The overall blood transfusion rate was 7.1%. Complications were observed in nine patients (16.1%), including selective renal artery embolization, fever, gross haematuria and steinstrasse in one, two, three and three cases, respectively. At a mean follow-up of 31 months, available in 38 patients, kidney function was stable in 71%, improved in 26.3% and worsened in 2.7%, according to serum creatinine levels that remained within ±20%, or that increased or decreased outside this range. No patient required haemodialysis.

CONCLUSIONS

Combining single-tract PCNL with subsequent RIRS was an effective strategic option for treating staghorn stones in solitary kidneys. The method gave an excellent SFR, satisfactory preservation of renal function, reduced bleeding risk and potentially less morbidity than that associated with multiple-tract PCNL.

Initial experience of micro-percutaneous nephrolithotomy in the treatment of renal calculi in 140 renal units

The aim of this study was to investigate the effectiveness and reliability of the micro-percutaneous nephrolithotomy (PNL) method for the management of kidney stones. We performed a retrospective analysis of 136 patients (140 renal units) who underwent micro-PNL for renal stones between September 2011 and February 2013 in four referral hospitals in Turkey. The selection of treatment modality was primarily based on factors such as stone size and location. In this study, we analyzed patient- and procedure-related factors. The mean age of patients in this study was 28.7 ± 20.6 (1-69) years, and the mean stone size was 15.1 ± 5.15 (6-32) mm. Conversion to mini-PNL was required in 12 patients. All interventions were performed with the patient in the prone position, except for the 3-year-old patient with the pelvic kidney who was placed in the supine position. The mean hospital stay was 1.76 ± 0.65 (1-4) days, and the mean drop in the hemoglobin level was 0.87 ± 0.84 (0-4.1) mg/dL. One of our patients required transfusion. Ureteral J stent was implanted in nine (6.43 %) patients because of residual stones. Seven (6.43 %) patients complained of postoperative renal colic which was managed conservatively. Abdominal distension related to extravasation of the irrigation fluid was observed in three patients (2.19 %). There were no other postoperative complications. An overall success rate of 82.14 % was achieved. Micro-PNL can be effectively and safely used for small and moderate kidney stones resistant to shock wave lithotripsy or as an alternative to other minimally invasive treatment methods.

Endoscopic combined intrarenal surgery for large calculi: simultaneous use of flexible ureteroscopy and mini-percutaneous nephrolithotomy overcomes the disadvantageous of percutaneous nephrolithotomy monotherapy

BACKGROUND AND PURPOSE

Percutaneous nephrolithotomy (PCNL) is considered the standard procedure for the removal of large renal calculi. The development of the "minimally invasive PCNL" (mini-PCNL) has reduced the complications of the surgery; it also appears to be associated with less morbidity than the conventional PCNL (con-PCNL). This study aimed at evaluating the efficacy of endoscopic intrarenal surgery, using the prone-split leg position, using flexible ureteroscopy and mini-PCNL (mini- endoscopic combined intrarenal surgery [ECIRS]) by retrospectively comparing this technique with mini-PCNL and con-PCNL.

PATIENTS AND METHODS

In total, 161 consecutive patients who were observed for the follow-up of large renal calculi between February 2004 and January 2013 were selected for mini-ECIRS (60), mini-PCNL (19), or con-PCNL (82). Mini-ECIRS was performed with patients in the prone split-leg position via 18F minipercutaneous tract and 14F ureteral access sheath. The mini-PCNL was performed via 18F percutaneous tract and con-PCNL performed via the 30F tract. Mean size of the renal calculi removed via mini-ECIRS, mini-PCNL, and con-PCNL were 39.2, 38.4, and 34.6 mm, respectively.

RESULTS

Average surgical time for mini-ECIRS was shorter than that for mini-PCNL and con-PCNL (120.5 vs. 181.9 vs 134.1 min, respectively; P<0.001). The stone-free rate for mini-ECIRS was significantly higher than that of the other procedures (initial rates 81.7% vs. 38.9% vs. 45.1%, respectively; P<0.001; rates after further treatment 86.7% vs. 61.1% vs. 61.0%, respectively; P=0.002). Only one patient in the mini-ECIRS group needed blood transfusions. The decrease in hemoglobin during mini-ECIRS and mini-PCNL was significantly lower than that during con-PCNL (P=0.011).

CONCLUSION

Mini-ECIRS is better than monotherapy with mini-PCNL or con-PCNL. The study results show that mini-ECIRS is a safe, efficient, and versatile procedure that can be effective for the management of renal calculi.

The Post-Ureteroscopic Lesion Scale (PULS): a multicenter video-based evaluation of inter-rater reliability

PURPOSE

The Post-Ureteroscopic Lesion Scale (PULS) offers a simple grading system for the description of ureteral lesions after ureteroscopy. In this article, we present the results of a video-based multicenter evaluation of the inter-rater reliability of clinically important PULS grades 0-3.

METHODS

Video sequences at the end of ureteroscopy (final passage) were recorded for 100 consecutive patients at a single institution and assessed by experienced urologists (n = 20) and senior residents (n = 17) at 19 international centers. The cohort included only patients with lesions grades 0-3 (with grades 2 and 3 subsumed as 2 + since distinction is defined by an extravasation of contrast medium in fluoroscopy). The gradings were evaluated for inter-rater reliability and in terms of simplicity, validity, comprehensibility, reproducibility, and usefulness.

RESULTS

Overall, inter-rater reliability was high (Kendall's W = 0.69, p < 0.001) and was comparable between specialists (Kendall's W = 0.69, p < 0.001) and residents (Kendall's W = 0.71, p < 0.001). The matched ratings showed grade 0 in 43.0 % of patients and grades 1 or 2 + in 44.0 and 13.0 % of patients, respectively. Results of the questionnaires indicated a high degree of acceptance, with an overall rating of 1.76 (1.64-1.93 for different items, scale 1-6).

CONCLUSIONS

Inter-rater reliability of the endoscopically assessable PULS was high among urologists with different levels of experience in different countries worldwide. The validated PULS system may be used for standardized reporting of ureteral lesions/injuries after ureteroscopy. In addition, PULS will enable more selective standardization of indications for postoperative DJ stenting based on the randomized controlled trials.

Is tubeless percutaneous nephrolithotomy a feasible technique for the treatment of staghorn calculi?

Purpose

Tubeless percutaneous nephrolithotomy (PNL) remains a challenging technique for the surgical treatment of staghorn renal calculi. Our study was designed to compare surgical outcomes between conventional and tubeless PNL.

Materials and Methods

We retrospectively enrolled consecutive patients who underwent conventional or tubeless PNL under general anesthesia performed by a single surgeon (H.J.) for the treatment of staghorn calculi between 2003 and 2012. All patients were divided into two groups: group 1 included patients who underwent conventional PNL and group 2 included patients who were managed by tubeless PNL for the treatment of staghorn calculi. Preoperative and postoperative parameters were analyzed between the two groups, including age, stone burden, complications, any interventions, and duration of hospital stay.

Results

A total of 165 patients (group 1, 106; group 2, 59) were enrolled in the study. No significant differences in age, sex, body mass index, or stone laterality were observed between the two groups. The mean stone burdens (±standard deviation) of group 1 and group 2 were 633.6 (±667.4) and 529.9 (±362.8), respectively (p=0.271). The postoperative stone-free clearance rate was higher in group 2 (78.0%) than in group 1 (69.8%); however, the difference was not clinically significant (p=0.127). In addition, no significant differences in postoperative complications, including fever, bleeding, infection, or additional interventions, were observed between the two groups.

Conclusions

Our results demonstrated that tubeless PNL has the same effectiveness and safety as conventional PNL in the treatment of staghorn calculi. Tubeless PNL may be feasible for managing renal staghorn calculi.

Factors affecting complication rates of percutaneous nephrolithotomy in children: results of a multi-institutional retrospective analysis by the Turkish pediatric urology society

PURPOSE

We assessed factors affecting complication rates of percutaneous nephrolithotomy in children.

MATERIALS AND METHODS

We retrospectively evaluated data on 1,205 renal units in 1,157 children treated with percutaneous nephrolithotomy at 16 Turkish centers between 1991 and 2012. Of the patients 28.3% had a history of urolithiasis. Complications were evaluated according to the Satava classification system and modified Clavien grading system. Univariate and multivariate analyses were done to determine predictive factors affecting complication rates.

RESULTS

A total of 515 females and 642 males were studied. Mean ± SD patient age was 8.8 ± 4.7 years (range 4 months to 17 years). Mean ± SD stone size, operative time and postoperative hospital stay were 4.09 ± 4.06 cm(2), 93.5 ± 48.6 minutes and 5.1 ± 3.3 days, respectively. Postoperative stone-free rate was 81.6%. A total of 359 complications occurred in 334 renal units (27.7%). Complications were intraoperative in 118 cases and postoperative in 241. While univariate analysis revealed that stone history, positive urine culture, operative time, length of hospitalization, treatment success, punctured calyx and location of the stone significantly affected the complication rates (p <0.05), operative time, sheath size, mid calyceal puncture and partial staghorn formation were the statistically significant parameters affecting complication rates on multivariate logistic regression analysis.

CONCLUSIONS

Percutaneous nephrolithotomy is the treatment of choice for most renal calculi in children. The technique is effective and safe in children, with a high success rate and a low rate of major complications. The significant factors identified should be considered by clinicians to decrease associated complication rates.

Calcular pulmonary embolism

Many complications of percutaneous nephrolithotomy(PNL) were reported. In this report, we present a rare complication, which has never been reported. It is the migration of stone fragments into the venous system causing pulmonary emboli. We reviewed the literatures reporting complications following PNL, and there was no available previous report about such complication. It was suspected intraoperative and confirmed radiologically postoperative. In this case, pulmonary emboli have had no clinical consequences and were managed conservatively.

Percutaneous nephrolithotomy under local infiltration anesthesia: a single-center experience of 2000 Chinese cases

OBJECTIVE

To determine the feasibility and safety of percutaneous nephrolithotomy (PCNL) in treating upper urinary calculi under local infiltration anesthesia.

METHODS

A series of 2000 patients with upper urinary calculi underwent PCNL under local infiltration anesthesia. Of the 2000 patients, 536 had upper ureteral calculi, 805 patients had pelvic calculi, and 659 patients had complex renal calculi. Pethidine premedication (75-100 mg) and Phenergan (25 mg) were used half an hour preoperatively. The mean pain scores at 0, 6, 24, and 48 hours postoperatively, the demographic characteristics, and the stones characteristics were evaluated to determine the feasibility. The complications were evaluated to determine the safety, and stone-free rate was evaluated to determine effectivity.

RESULTS

The mean American Society of Anesthesiologists score was 1.55 ± 0.54 (range, 1-3). The mean operative time was 48 minutes (range, 20-125). The mean Visual Analogue Scale scores at 0, 6, 24, and 48 hours postoperatively were 3.62, 3.02, 2.27, and 2.09, respectively. The mean hemoglobin drop was 1.06 g/dL (range, 0.2-6.8). Sixty-five patients (3.3%) received transfusions, 10 patients (0.5%) required selective renal angioembolism (Clavien grade II), and 1 patient (0.05%) received chest drainage therapy (Clavien grade II). The total stone-free rate was 85.8%.

CONCLUSION

Local infiltration anesthesia is a well-tolerated alternative anesthesia technique that provides effective intraoperative and postoperative analgesia for PCNL. PCNL performed under local infiltration anesthesia in a selected group of patients is feasible and provides satisfactory clinical outcomes. Comparative studies should be performed to classify efficacy, safety, tract quantity, dilation method, and the best candidates.

Evaluation of a novel fascial dilator modified with scale marker in percutaneous nephrolithotomy for reducing the X-ray exposure: a randomized clinical study

OBJECTIVE

To evaluate the role of the fascial dilators modified with a scale marker in reducing fluoroscopy time during percutaneous nephrolithotomy (PCNL).

METHOD

In a randomized clinical trial, eligible 100 consecutive patients anticipated to undergo single-tract PCNL were randomly assigned into two groups by the closed envelope method, to compare the efficacy and safety of the modified scale fascial dilator (group 1, n=50) and traditional nonscale fascial dilator (group 2, n=50) with respect to the X-ray exposure duration as well as the outcome of PCNL.

RESULTS

There was no significant difference between group 1 and group 2 regarding to the initial successful access rate (100% v 96%), operative time (79.4 v 83.7 minutes), the initial stone-free rate (82% v 81.3%), complications (24% v 20%), and bleeding required blood transfusion (4% v 6%) (all p>0.05). The mean operative duration and fluoroscopic time for tract dilation in group 1 and group 2 were 164.4 ± 19 seconds v 168.3 ± 14 seconds, and 3.2 ± 0.9 seconds v 22.2 ± 4.6 seconds, (p=0.250 and p<0.001), respectively.

CONCLUSIONS

Compared to the use of nonscaled dilators, using the scaled fascial dilators for a percutaneous access in PCNL was found to be associated with less radiation hazards along with similar stone-free rate and complications.

Emergent intervention criterias for controlling sever bleeding after percutaneous nephrolithotomy

Objectives. To determine when emergent intervention for bleeding after percutaneous nephrolithotomy (PCNL) is required. Methods. We reviewed analysis data of 850 patients who had undergone PCNL in our center. Blood transfusion was needed for 60 (7%) patients during and/or after surgery. We routinely performed followup of the urine output per hour, blood pressure, and hemoglobin levels after PCNL. Five (0.6%) of them had severe bleeding that emergent intervention was needed. Results. The mean age of the 5 patients who had emergent surgery due to severe bleeding was 42.2 (19–56) years. Mean duration of surgery was 44.75 (25–65) minutes. Mean stone size was 27 (15–38) mm. Mean decrease of hemoglobin was 4.8 (3.4–5.8) ng/dL, and unit of transfused blood was 4.4 (3–6). Mean blood pH was 7.21. There were metabolic acidosis and anuria/oliguria in all these patients. One of 5 patients suffered from cardiopulmonary arrest because of massive bleeding four hours after the PCNL, and despite cardiac resuscitation, he died. Hemorrhaging was controlled by open surgery in the other 4 patients. Two patients experienced cardiac arrest during the open surgery but they responded to cardiac resuscitation. There were no metabolic asidosis and anuria/oliguria, and bleeding was managed only with blood transfusion for the other 55 patients. Conclusion. Severe bleeding after PCNL is rare and can be mortal. If metabolic asidosis and anuria/oliguria accompanied the drop of hemoglobin, emergent surgical intervention should be performed because vascular collapse may follow, and it may be too difficult to stabilise the patient.

A novel technique of ultra-mini-percutaneous nephrolithotomy: introduction and an initial experience for treatment of upper urinary calculi less than 2 cm

Objectives. To describe our novel modified technique of ultra-mini-percutaneous nephrolithotomy (UMP) using of a novel 6 Fr mininephroscope through an 11–13 Fr metal sheath to perform holmium: YAG laser lithotripsy. Methods. The medical records of 36 patients with moderate-sized (<20 mm) kidney stones treated with UMP from April to July 2012 were retrospectively reviewed. Patients were assessed at the 1st day and 1st month postoperatively by KUB and US to assess stone-free status. Results. The mean stone size was 14.9 ± 4.1 mm (rang: 6–20). The average operative time was 59.8 ± 15.9 (30–90) min. The stone-free rate at postoperative 1st day and 1st month was 88.9% and 97.2%. The mean hospital stay was 3.0 ± 0.9 (2–5) days. Complications were noted in 6 (16.7%) cases according to the Clavien classification, including sepsis in 2 (5.6%) cases (grade II), urinary extravasations in 1 (2.8%) case (grade IIIa), and fever in 3 (8.3%) cases (grade II). No patients needed blood transfusion. Conclusions. UMP is technically feasible, safe, and efficacious for moderate-sized renal stones with an advantage of high stone-free rates and low complication rates. However, due to the limits of its current unexplored indications, UMP is therefore a supplement to, not a substitute for, the standard mini-PCNL technology.

[Calyceal stones]

The natural course of untreated, asymptomatic calyceal calculi has not yet been clearly defined regarding disease progression and risk of surgical interventions. The decision for an active treatment of calyceal calculi is based on stone composition, stone size and symptoms. Extracorporeal shockwave lithotripsy (ESWL) has a low complication rate and is recommended by the current guidelines of the German (DGU) and European (EAU) Associations of Urology as a first-line therapy for the treatment of calyceal stones <2 cm in diameter. However, immediate removal of stones is not achieved with ESWL. The primary stone-free rates (SFR) after ESWL depend on stone location and stone composition and can show remarkable differences. Minimally invasive procedures, such as percutaneous nephrolitholapaxy and ureteroscopy are alternatives for the treatment of calyceal stones which have low morbidity and high primary SFR when performed in centres of excellence.

Predictive factors for bleeding during percutaneous nephrolithotomy

Purpose

Although percutaneous nephrolithotomy (PCNL) has been accepted as a standard method for the management of large renal stones, the incidence of renal hemorrhage is relatively high. This study investigated the variables that affect bleeding during PCNL.

Materials and Methods

The medical records of 370 patients who underwent PCNL by a single surgeon from January 2005 to December 2010 were reviewed retrospectively. All patients were divided into two groups according to median blood loss (lesser bleeding group and higher bleeding group). Various clinical and perioperative factors including age, sex, stone size and position, degree of hydronephrosis, operative time, underlying disease, history of anticoagulant medication, presence of previous nephrostomy catheter, stone composition, and thickness of the renal cortex were assessed. For statistical assessment, univariate and multivariate logistic regression analyses were used.

Results

The mean patient age was 48.8 years (range, 22 to 75 years). Forty-three patients (11.6%) received a transfusion and 9 patients (2.4%) underwent angioembolization after surgery. The mean blood loss was 511.8±341.3 mL. Body mass index (BMI), stone size, stone position, operation time, and degree of preoperative hydronephrosis were predictive factors for severe bleeding during PCNL.

Conclusions

On the basis of the results achieved by a single surgeon, staghorn stones, high BMI, large stones, prolonged operation time, and absence of hydronephrosis were significantly associated with the risk of severe bleeding during PCNL.

Clavien classification in urology: Is there concordance among post-graduate trainees and attending urologists?

PURPOSE

We assess the variations between post-graduate trainees (PGTs) and attending urologists in applying the Revised Clavien-Dindo Classification System (RCCS) to urological complications.

METHODS

Twenty postoperative complications were selected from urology service Quality Assurance meeting minutes spanning 1 year at a tertiary care centre. The cases were from adult and pediatric sites and included minor and major complications. After a briefing session to review the RCCS, the survey was administered to 16 attending urologists and 16 PGTs. Concordance rates between the two groups were calculated for each case and for the whole survey. Inter-rater agreement was calculated by kappa statistics.

RESULTS

There was good overall agreement rate of 81 % (range: 30-100) when both groups were compared. Thirteen of the 20 cases (65%) held an agreement rate above 80% (k = 0.753, p < 0.001) including 3 (15%) cases with 100% agreement. There were only 2 cases where the scores given by PGTs were significantly different from that given by attending urologists (p ≤ 0.03). There was no significant difference between both groups in terms of overall RCCS grades (p = 0.12). When all participants were compared as one group, there was good overall inter-rater agreement rate of 75% (k = 0.71). Although the percent of overall agreement rate among PGTs was higher than the attending urologists (82% [k = 0.79] vs. 69% [k = 0.64]), this was not significantly different (p = 0.68).

CONCLUSION

There was good overall agreement among PGTs and attending urologists in application of the RCCS in urology. Therefore, it is appropriate for PGTs to complete the Quality Assurance meeting reports.

Study of predictive factors for complications after percutaneous nephrolithotomy according to the Clavien classification

OBJECTIVE

Set predictors of complications in percutaneous nephrolithotomy (PCNL) using the modified Clavien system.

MATERIAL AND METHODS

Retrospective study included 172 PCNL in Galdakao position made in the La Ribera Hospital between January 2005 and December 2011. They classified the complications of these procedures using the modified Clavien system. We performed a univariate analysis (Chi(2) Test and Cramer's V) and multivariate (logistic regression) of predictors of these complications (P < .05).

RESULTS

In 49 of the 172 procedures complications were detected (28.5%).The most frequent complications were grade 1 (9.9%), 12 complications (6.9%) were classified as grade 2 by requiring additional medical treatment, 6 as grade 3A (3.5%), 7 as grade 3B (4.1%), 2 and 4A (1.1%), 4 and 4B (2.3%) and one and 5 (0.6%). In the univariate analysis, positive urine culture before surgery, the stones complex and larger than 40 mm of the same, showed a statistically significant association with the occurrence of complications (P < .05). The positive culture (OR: 2.96) and complex stones (OR: 3.03) proved to be independent variables predicting complications in multivariate analysis.

CONCLUSIONS

Clavien system allows a common language for classifying complications, expressing the degree of the same as the complexity of treatment required for resolution. The preoperative urine culture positivity and complex stone proved predictors of these complications in our serie.