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

Is standard percutaneous nephrolithotomy still the standard treatment modality for renal stones less than three centimeters?

OBJECTIVE

The aim of study was to compare the efficiency and safety of standard percutaneous nephrolithotomy (sPNL) and miniaturized percutaneous nephrolithotomy (mPNL) in lower calyx and/or pelvic stones smaller than three centimeters.

MATERIAL AND METHODS

From October 2010 to August 2015, 108 mPNL and 176 sPNL procedures were performed for renal stones smaller than three cm and located in the lower calyx and/or renal pelvis. All patients were evaluated preoperatively with intravenous pyelography and/or computed tomography. Intraoperative parameters, post-operative results and complications were recorded. Postoperative success was defined as complete stone clearance and/or clinically insignificant residual fragments at 3^rd month.

RESULTS

Preoperative characteristics were similar between sPNL and mPNL groups except previous renal stone operation history and gender. The mean operation time was significantly shorter in the sPNL group (p<0.001). The mean hemoglobin drop was significantly less in the mPNL group (p=0.001), we found a 1.27±1.4 and 0.5±1.3 decrease in mean hemoglobin levels (mg/dL) in the sPNL and mPNL groups, respectively. Transfusion rate was 1.9% in mPNL and 5.6% in sPNL groups, and the difference was statistically significant (p=0.048). Only one patient in the sPNL group needed angiography and embolization. Postoperative JJ stent insertion rate was significantly higher in the mPNL group (p=0.03).

CONCLUSION

Both sPNL and mPNL are safe and effective surgical procedures for lower calyx and/or pelvis stones smaller than 3 cm. However, use of smaller caliber instruments was associated with a lesser hemoglobin drop and need for transfusion.

Implementation of minimally invasive percutaneous nephrolithotomy (MIP): comparison of the initial learning curve with the later on clinical routine in a tertiary centre

OBJECTIVE

We report on the comparison of clinical results of the early phase of implementation of minimally invasive PNL (MIP) in a mentor-based approach with the later on clinical routine in a tertiary centre.

PATIENTS AND METHODS

From January 2010 until January 2015 MIP was performed in 190 patients. Stone and patient characteristics were recorded in prospective manner. Perioperative complications were recorded within the Clavien-Classification. The first 120 consecutive patients undergoing MIP were evaluated and divided into three groups of 40 patients each. Mentor-based introduction of MIP was done within the first 40 patients (group A). Further patients were treated on routine clinical practice basis (group B and C). Treatment outcome was compared within the three groups.

RESULTS

The groups did not significantly differ with regard to patient characteristics, operation time and decline in haemoglobin. In the mentor-based series mean stone size was 21.7 ± 12.6 vs. 15.6 ± 7.9 and 16.1 ± 8.4 mm in group B and C (p = 0.033). Primary stone-free rates were 65, 87.5 and 87.5% for the three groups (p = 0.015). Stone-free rate was higher in smaller and simple stones. Overall, complication rate was 41.7% including 36.7% Clavien grade I and II complications.

CONCLUSIONS

MIP can be implemented safe and effectively with mentor-based approach. MIP has a high safety profile, which allows high safety and efficacy of MIP at the time of implementation.

Mini PCNL for renal calculi: does size matter?

OBJECTIVE

To evaluate the minimally invasive percutaneous nephrolithotomy (MIP) system for renal calculi.

PATIENTS AND METHODS

Consecutive patients undergoing mini-percutaneous nephrolithotomy (mPCNL) procedures with the MIP system were enrolled. Patient position, American Society of Anesthesiologists classification, puncture location, stone clearance, postoperative drainage and complications were recorded, and features unique to MIP were noted.

RESULTS

In all, 30 patients underwent 32 mPCNL procedures. The mean stone size was 17 (10.75-21.25) mm and the mean number of stones was 1 (1-2). The median stone clearance rate was 96.5 (95-100)%. The complication rate was 9.3%. No patient required a transfusion. In addition to these outcomes, we noted that the MIP system has many advantages over conventional PCNL (cPCNL). It is easy to learn and can be performed in both supine and prone positions. It is safe for supracostal puncture, provides excellent access to nearly all calyces and upper ureter, has multiple stone treatment options, can be used as an adjunct to cPCNL, and can be performed as a tubeless procedure.

CONCLUSION

Our experience with the MIP system has shown several advantages over cPCNL. mPCNL with the MIP system has several features that suggest it should be considered as an alternative or adjunct to cPCNL, ureteroscopy and extracorporeal shockwave lithotripsy.

Is it Necessary to Perform Nephrostography before Tube Removal after Percutaneous Nephrolithotomy

BACKGROUND

The aim of this study is the caparison of the complications rate among the patients which underwent nephrostomy removal with and without performing nephrostography.

MATERIALS AND METHODS

Between October 2010 and November 2011, 200 patients who underwent standard percutaneous nephrolithotomy (PCNL) procedures were included in this study. The patients were randomly assigned into two groups, Group A (n = 100) did not undergo the antegrade nephrostography on postoperative day 2 and the patients were discharged keeping the nephrostomy until postoperative day 3, while in Group B (n = 100) the nephrostomy tube was removed on postoperative day 3 after antegrade nephrostography demonstrating ureteral drainage down to the bladder. Postoperative complications in both groups were recorded and compared between two groups.

RESULTS

A total of 200 patients were treated with standard PCNL. The persistent leakage of urine after removal of the nephrostomy tube was encountered in 5 (5.0%) and 3 (3%) of patients in Groups 1 and 2, respectively. Urinary leakage was resolved with conservative management in 3 and 2 patients of Groups 1 and 2, respectively, but a double-J stent was inserted in 2 and 1 patients in each group because of persistent leakage of urine more than 1-week. The two groups show comparable complications such as prolonged urinary leakage which managed in a similar manner, however, postoperative hospital stay was lesser in Group 1.

CONCLUSION

Our results revealed postoperative performing nephrostogramy before tube removal changed the planning of complications such as prolonged urinary leakage and could be omitted in cases.

The Effect of Peritubal Infiltration with Bupivacaine and Morphine on Postoperative Analgesia in Patients Undergoing Percutaneous Nephrolithotomy

Objective. We aimed to investigate the effect of peritubal local anesthetic and opioid infiltration on pain scores and analgesic consumption in patients who underwent percutaneous nephrolithotomy. Material and Methods. Patients aged between 18 and 65 years and ASA I-III were included in this double-blind, randomized study. The patients were divided into two groups. All patients underwent spinoepidural anesthesia. 20 mL of 0.25 percent bupivacaine + 5 mg morphine (0.5 mL), in Group P (n = 66), infiltrated the renal capsule, perinephric fat, muscles, subcutaneous tissue, and skin under fluoroscopy. In Group C (n = 64), none of the patients received a peritubal injection. In the first 24 h pain scores, time of the first analgesic demand, the mean number of analgesic demands, and postoperative complications were compared between groups. Results. The mean VAS score at postoperative 8, 12, and 24 h and dynamic VAS score at postoperative 4, 8, 12, and 24 h were significantly lower in Group P. VAS score at postoperative 4 h was not significant. Time of the first analgesic demand was significantly longer in Group P. Conclusion. Our study results suggest that peritubal infiltration of bupivacaine with morphine after percutaneous nephrolithotomy is an effective method for postoperative pain control and reduces analgesic consumption.

Surgical outcomes of percutaneous nephrolithotomy in 3402 patients and results of stone analysis in 1559 patients

OBJECTIVE

To report our experience of a series of percutaneous nephrolithotomy (PCNL) procedures in a single centre over 18 years in terms of patient and stone characteristics, indications, stone clearance and complications, along with the results of chemical analysis of stones in a subgroup.

PATIENTS AND METHODS

We retrospectively analysed the outcomes of PCNL in 3402 patients, who underwent the procedure between 1997 and 2014, obtained from a prospectively maintained database. Data analysis included patients' age and sex, laboratory investigations, imaging, punctured calyx, duration of operation, volume of irrigation fluid, radiation exposure time, blood transfusion, complications and stone-free status at 1-month follow-up. For the present analysis, outcomes in relation to complications and success were divided in two eras, 1997-2005 and 2006-2014, to study the differences.

RESULTS

Of the 3402 patients, 2501 (73.5%) were male and 901 (26.5%) were female, giving a male:female ratio of 2.8:1. Staghorn (partial or complete) calculi were found in 27.5% of patients, while 72.5% had non-staghorn calculi. Intracorporeal energy sources used for stone fragmentation included ultrasonography in 917 patients (26.9%), pneumatic lithoclast in 1820 (53.5%), holmium laser in 141 (4.1%) and Lithoclast^® master in 524 (15.4%). In the majority of patients (97.4%) a 18-22-F nephrostomy tube was placed after the procedure, while 69 patients (2.03%) underwent tubeless PCNL. The volume of the irrigation fluid used ranged from 7 to 37 L, with a mean of 28.4 L. The stone-free rate after PCNL in the first era studied was 78%, vs 83.2% in the second era, as assessed by combination of ultrasonography and plain abdominal film of the kidney, ureter and bladder. The complication rate in the first era was 21.3% as compared with 10.3% in the second era, and this difference was statistically significant. Stone analysis showed pure stones in 41% and mixed stones in 58% of patients. The majority of stones consisted of calcium oxalate.

CONCLUSIONS

This is the largest series of PCNL reported from any single centre in Pakistan, where there is a high prevalence of stone disease associated with infective and obstructive complications, including renal failure. PCNL as a treatment method offers an economic and effective option in the management of renal stone disease with acceptable stone clearance rates in a resource-constrained healthcare system.

Acute kidney injury after percutaneous nephrolithotomy for stones in solitary kidneys

OBJECTIVES

The aim of this study was to report the incidence, severity, outcome and risk factors of acute kidney injury (AKI) following percutaneous nephrolithotomy (PNL) in solitary kidneys.

METHODS

The study included consecutive adult patients who underwent PNL for treatment of calculi in a solitary kidney between May 2012 and July 2015. Patients with congenital renal anomalies or with stages 4 and 5 chronic kidney disease (CKD) were excluded. Serum creatinine levels were measured the day before PNL, daily after PNL for 2-5 days and after 3 months. AKI was depicted according to changes in early postoperative serum creatinine levels and its severity was determined based on the Acute Kidney Injury Network (AKIN) classification. The outcome of AKI was evaluated after 3 months by changes in the stage of CKD. Univariate and multivariate statistical analyses were conducted to determine risk factors for developing AKI.

RESULTS

The study included 100 patients (62 males) with a mean ± SD age of 50 ± 11.7 years. Complications were reported for 27 patients. AKI developed in 25 patients; at the 3 month follow-up, 23 of them (92%) had completely recovered from AKI and two (8%) had developed stage 4 CKD. Independent risk factors for developing AKI were multiple PNL tracts and postoperative ureteric obstruction (relative risks were 14 and 22, respectively).

CONCLUSIONS

The incidence of AKI was 25% after PNL for a solitary kidney. The likelihood of renal function recovery was 92%. Multiple PNL tracts and postoperative ureteric obstruction were risk factors for developing AKI.

Comparison of Effect of Minimally Invasive Percutaneous Nephrolithotomy on Split Renal Function: Single Tract vs Multiple Tracts

OBJECTIVES

To observe serum creatinine (SCr) and treated side glomerular filtration rate (TGFR) variations in patients with upper urinary tract calculi after minimally invasive percutaneous nephrolithotomy (MPCNL).

PATIENTS AND METHODS

A total of 178 patients underwent MPCNL in our institute and they were retrospectively evaluated between May 2014 and February 2016. SCr and TGFR variations were observed with renal scintigraphy using 99mTc-diethylene triamine pentaacetic acid (^99mTc-DTPA) preoperatively and after at least 6 months of follow-up (FU). The patients were categorized into two groups according to the number of percutaneous access tracts: group I (single tract, n = 122) and group II (multiple tracts, n = 56).

RESULTS

At a mean FU of 7.6 months, SCr dropped from 192.9 ± 151.9/L to 167.6 ± 113.9 μM (13.15% decrease, p = 0.008) and TGFR increased from 29.8 ± 21.2 mL/minute preoperatively to 32.7 ± 22.5 mL/minute postoperatively (9.79% increase, p = 0.022) in group I. Similarly, SCr dropped from 238.5 ± 130.1 to 215.8 ± 128.1μ (9.50% decrease, p = 0.013) and TGFR increased from 29.6 ± 21.4 mL/minute preoperatively to 32.9 ± 25.1 mL/minute postoperatively (11.17% increase, p = 0.014) in group II. No statistically significant difference between two groups according to SCr or TGFR variation was observed (p > 0.05).

CONCLUSIONS

Stone clearance resulted in improvement of split kidney function after single tract or multiple tract MPCNL. Single tract or multiple tract MPCNL did not show statistically significant difference in split renal function postoperative recovery.

The Evaluation of Risk Factors for Postoperative Infectious Complications after Percutaneous Nephrolithotomy

This study was to evaluate the risk factors of infectious complications after percutaneous nephrolithotomy (PCNL) and build a prediction tool for postoperative complications based on the risk factors. A total of 110 male (67.1%) and 54 female (32.9%) patients who underwent PCNL for renal stones between 2010 and 2014 in our institute were included. A detailed clinical information and laboratory results were obtained from patients. Systemic inflammatory response syndrome (SIRS) and postoperative fever were recorded after PCNL surgery. In all, 45 cases (27.4%) developed SIRS and fever was observed in 20 cases (12.2%). In multivariate analysis, stone size (odds ratio, OR = 1.471, p = 0.009) and urine white blood cell (WBC) (OR = 1.001, p = 0.007) were related to the development of SIRS. Stone size (OR = 1.644, p = 0.024), urine WBC (OR = 1.001, p = 0.002) and serum albumin (OR = 0.807, p = 0.021) were associated with postoperative fever. We concluded that patients with larger stone size and preoperative urinary tract infection might have a higher risk of developing SIRS and fever after operation, while a high-normal level of serum albumin might be the protective factor for postoperative fever.

Immediate versus delayed shockwave lithotripsy for inaccessible stones after uncomplicated percutaneous nephrolithotomy

Objective

To evaluate the efficacy and safety of immediate versus delayed shockwave lithotripsy (SWL) for inaccessible stones after uncomplicated percutaneous nephrolithotomy (PCNL).

Patients and methods

Between December 2011 and June 2014, patients with residual inaccessible stones after uncomplicated PCNL were prospectively randomised into two treatment groups; Group I, immediate SWL and Group II, delayed SWL at 1 week after PCNL. Patients with residual stones of ⩾1.5 cm, a stone density of >1000 Hounsfield units and body mass index of >40 kg/m² were excluded from the study. The following data were reported: patients’ demographics, stone characteristics after PCNL, hospital stay, perioperative complications, stent duration, and stone-free rate (SFR).

Results

In all, 84 patients (51 males and 33 females) with mean (SD) age of 39 (8.5) years were included in the study. Group I included 44 patients, whilst Group II included 40 patients. There was no statistically significant difference amongst the groups for patients’ demographics, stone characteristics, and perioperative complications. The hospital stay was significantly shorter in Group I, at a mean (SD) of 34 (3.7) vs 45 (2.9) h (P < 0.001). The duration of ureteric stenting was significantly lower in Group I as compared to Group II, at a mean (SD) of 12 (4.2) vs 25 (3.5) days (P < 0.001). The SFR was 93.2% and 95% in Groups I and II, respectively (P = 0.9).

Conclusions

Immediate SWL after PCNL is as effective and safe as delayed SWL with a lesser hospital stay and duration of ureteric stenting.

The role of ultra-mini percutaneous nephrolithotomy in the treatment of kidney stones

OBJECTIVE

In our study we aimed to evaluate outcomes of ultra-mini-percutaneous nephrolithotomy (UMP) performed for the treatment of kidney stones.

MATERIAL AND METHODS

Between October 2014 and September 2015, a single surgeon performed UMP on a total of 49 consecutive patients with symptomatic kidney stones at our center. Pregnants, anticogulant users, patients with bleeding diathesis pyonephrosis, and partial/complete staghorn stones were excluded from the study. Patient characteristics, operative data and postoperative outcomes were assessed in detail.

RESULTS

The UMP was performed on 50 (34 right/16 left) renal units of the 48 (28 male/20 female) patients included in this study. The mean age and body mass index was 36.5 (2-83) years and 26.2 (17.6-32.8) kg/m², respectively. Mean stone size was calculated as 22.2 (10-55) mm. The mean durations of the operations and fluoroscopic examination were calculated as 65.4 (20-120) minutes and 89.4 (9-322) seconds, respectively. The mean duration of hospitalization was 1.4 (1-5) days. In 52% of the patients the procedure was terminated tubeless. Mean hemoglobin drop was 0.6 (0-3) g/dL. Our series experienced a 10% complication rate. The UMP procedure was successful in 96% of the renal units at the 1^st month control visit assessment.

CONCLUSION

The outcomes of our study have demonstrated that UMP is an effective and safe treatment modality, especially in the treatment of medium-sized renal calculi.

Guy's Stone Score (GSS) Based on Intravenous Pyelogram (IVP) Findings Predicting Upper Pole Access Percutaneous Nephrolithotomy (PCNL) Outcomes

Objective. To predict the success rate and complications following percutaneous nephrolithotomy via the upper pole using the Guy's Stone Score (GSS) based on the findings of a preoperative intravenous pyelogram (IVP). Patients and Methods. Two hundred and twenty-seven renal operations, which were carried out using PCNL via the upper pole, were classified according to the GSS assigned. Any complications were classified according to the Clavien classification. The success rates and incidence of any complications were compared between each GSS. Results. The immediate success rates were 87.50% of GSS1, 71.43% of GSS2, 53.62% of GSS3, and 38.46% of GSS4, P < 0.01. There were statistically significant differences between the groups in stone size, overall immediate success rate, operative time, number of access tracts, and frequency of tubeless PCNL. Major complications (a Clavien score of 3-5) were significantly higher in the cases with a higher GSS. Conclusion. A GSS based on an IVP is a simple and reliable tool in predicting the success rate and possible complications following upper pole access PCNL.

Efficacy and safety of percutaneous nephrolithotomy with adult standard size instruments in children under 3 years of age: a 10 years single-center experience

BACKGROUND

Using percutaneous nephrolitotomy (PCNL) with large adult instruments in treatment of pediatricurolithiasis is still in debate. This study was conducted to evaluate the efficacy and safety of PCNL with adult's instrument in treatment of patients less than 3 years old.

METHODS

Data on patient characteristics and outcomes for 261 consecutive children undergoing PCNL at a Labbafinejad University Hospital were collected prospectively from September 2006 to February 2016. Thirty-two children, with 34 renal units, who were treated with PCNL were enrolled in the study. All PCNL procedures were performed via subcostal approach with one access tract in all of them. Postoperative complications were evaluated according to the modified Clavien grading system.

RESULTS

The mean age of patients was 19.4 ± 6.2 months. Two patients had bilateral stones; thus, PCNL was performed on 34 kidney units. The mean size of the largest stone diameter was 17.5 ± 7.8 mm. The mean duration of procedures was 121.52 ± 29.05 minutes, ranging from 60 to 180 minutes. The most common complication was fever (n = 9, 26.4%), and hemorrhage that needs transfusion was the second one (n = 4, 11.7%). Seventeen patients with complications were in the first degree of Clavien complication system and five of them were in the second degree.

CONCLUSIONS

Due to our experience, utilizing PCNL with adult-sized instruments in management of urolithiasis in less than 3 years old children appeared to be effective and relatively safe.

Comparison of Mini-percutaneous Nephrolithotomy and Retrograde Intrarenal Surgery in Preschool-aged Children

OBJECTIVE

To compare the outcomes of mini-percutaneous nephrolithotomy (m-PCNL) and retrograde intrarenal surgery (RIRS) in treating renal stones in preschool-aged children.

MATERIALS AND METHODS

Forty-five patients treated with m-PCNL and 32 patients treated with RIRS for renal stones were compared retrospectively. The operative and postoperative outcomes of both groups were analyzed retrospectively.

RESULTS

The mean age and gender were similar between the groups. The mean stone size was 19.30 ± 4.21 mm for the RIRS group and 21.06 ± 5.61 mm for the PCNL group (P = .720). The mean operative times, fluoroscopy times, and hospitalization times were statistically higher in the PCNL group. The stone-free rates (SFRs) after a single procedure were 84.4% in the PCNL group and 75% in the RIRS group (P = .036). After auxiliary procedures, the overall SFRs reached 91.1% for the PCNL group and 90.6% for the RIRS group (P = .081). No major complications were observed for both groups. Minor complication (Clavien 1-3) rates were 15.5% and 12.5% for the PCNL and RIRC group, respectively (P = .385).

CONCLUSION

RIRS has some advantages over PCNL such as shorter hospitalization times, shorter fluoroscopy times, and shorter operative time in treating renal stones. However, PCNL achieves higher SFR after a single session.

Laparoscopic Ureterolithotomy

Background and Objective:

The present study retrospectively analyzed the data of 213 patients who underwent laparoscopic ureterolithotomy.

Methods:

We retrospectively analyzed the data of 213 patients, in whom we performed conventional laparoscopic ureterolithotomy from April 2006 and January 2015 based on the diagnosis of an upper or middle ureteral stone. Patients with large ureteral stones (>15 mm) or a history of failed shock-wave lithotripsy or ureteroscopy were included in the study. Although the retroperitoneal approach was preferred for 170 patients, the transperitoneal approach was used in the remaining 43 patients.

Results:

The mean patient age was 39.3 ± 12.0 years (range, 18–73). The study population was composed of 78 (26.7%) female and 135 (63.3%) male patients. The mean stone size was 19.7 ± 2.5 mm. The mean operative time was 80.9 ± 10.9 minutes, and the mean blood loss was 63.3 ± 12.7 mL. Intraoperative insertion of a double-J catheter was performed in 76 patients. The overall stone-free rate was 99%. No major complication was observed in any patient. However, conversion to open surgery was necessary in 1 patient.

Conclusion:

With high success and low complication rates, laparoscopic ureterolithotomy is an effective and reliable method that ensures quick recovery and may be the first treatment option for patients with large, impacted ureteral stones, as well as for those with a history of failed primary treatment.

Complications of percutaneous nephrolithotomy: classification, management, and prevention

PURPOSE OF REVIEW

Percutaneous nephrolithotomy (PCNL) provides the highest stone-free rate after one session and low morbidity rates in cases of large or multiple renal calculi. The classification, management, and prevention of complications of PCNL are reviewed.

RECENT FINDINGS

PCNL is a well tolerated and very effective procedure for the management of renal stones. Specific complications limit the surgical outcome of PCNL whereas the majority of the complications are resolving with conservative or minimally invasive management. Experience with the technique is important for minimizing complications. There is an ongoing effort to classify the complications and to achieve a consensus in reporting the complications and surgical outcome of the procedure.

SUMMARY

The knowledge of risk factors, complications, and their management is important for every endourologist. Establishing of a PCNL-specific classification system for reporting outcomes and complications could set the basis for further improvement of the PCNL technique and outcomes.

Day care PNL using 'Santosh-PGI hemostatic seal' versus standard PNL: A randomized controlled study

INTRODUCTION

To compare the outcomes of tubeless day care PNL using hemostatic seal in the access tract versus standard PNL.

MATERIAL AND METHODS

It was a prospective randomized controlled study. Cases were randomized to either the day care group with hemostatic seal (DCS) or the control group where patients were admitted and a nephrostomy tube was placed at the conclusion of surgery.

RESULTS

A total of 180 cases were screened and out of these, 113 were included in the final analysis. The stone clearance rates were comparable in both the groups. The mean drop in hemoglobin was significantly lower in DCS group than the control group (1.05 ±0.68 vs. 1.30 ±0.58 gm/dl, p = 0.038).Mean postoperative pain score, analgesic requirement (paracetamol) and duration of hospital stay were also significantly lower in the DCS group (3.79 ±1.23 vs. 6.12 ±0.96, 1.48 ±0.50 vs. 4.09 ±1.11 grams and 0.48 ±0.26 vs. 4.74 ±1.53 days respectively; p <0.05). The incidence of urine leakage through the access tract site was significantly lower in the DCS subgroup when compared to the controls (3.6% vs. 21.1%, p <0.05). Cases in the DCS group resumed their normal activities in a significantly shorter time (8.05 ±3.05 vs.18.42 ±4.42 days; p <0.05). Higher proportion of cases in the DCS group got re-admitted, although it was not a statistically significant number (7.1% vs. 1.8%; p = 0.21).

CONCLUSIONS

Tubeless day care PNL with composite hemostatic tract seal is considered safe. It resulted in a significant reduction of blood loss and analgesic requirement with significantly reduced hospital stay, nephrostomy tube site morbidity and time required to resume normal activity when compared to the standard PNL. However, patients must be compliant with the given instructions and should have access to a health care facility, as few of them may need re-admission.

An unusual cause of Grade IIIb Clavien complication of percutaneous nephrolithotomy: Broken and retained Malecot nephrostomy catheter

Percutaneous nephrolithotomy (PCNL) is a relatively safe operation with low rates of major complications. Clavien-Dindo classification is a validated system to record complications, although still needing standardization in reporting and scoring of complex and rare events. We report an unusual adverse incident that required interventional management and impacted the postoperative course. The case of a broken re-entry Malecot nephrostomy catheter as it was being removed on the third postoperative day of an otherwise uneventful PCNL is described. The retained part was removed by open-surgery under general anesthesia. This incident has upgraded the minimally invasive surgery to a Grade IIIb complicated procedure according to the modified Clavien classification. Patient data, procedure conditions, and surgical retrieval of the catheter are detailed. Although far from being life-threatening, this rare complication due to a broken and retained drainage catheter is regarded as a high-grade complication according to the Clavien system.

The modified ultra-mini percutaneous nephrolithotomy technique and comparison with standard nephrolithotomy: a randomized prospective study

To compare the success and complications of ultra-mini percutaneous nephrolithotomy (UPNL) and standard percutaneous nephrolithotomy (SPNL) techniques. We prospectively analyzed 50 patients who underwent SPNL, and 47 patients who underwent UPNL. The patients with a stone size equal to or smaller than 25 mm and we used flipping a coin as the randomization technique. The mean stone size was 20.9 ± 3.6 mm in SPNL, and 20.3 ± 3.0 mm in ultra-mini PNL groups. Stone free rates were 88 % (44/50 patients) and 89.3 % (42/47 patients) in SPNL and UPNL groups, respectively, without any significant difference in between (p = 0.33). No major complications were seen in the UPNL group. PNL has been modified into micro PNL and UPNL parallel to the technological advances to decrease the complications of PNL. When performed as we do UPNL may be an alternative method to SPNL without any additional smaller-calibred nephroscope and with a similar high success rate.

Percutaneous Nephrolithotomy: Current Clinical Opinions and Anesthesiologists Perspective

Percutaneous nephrolithotomy (PCNL), a minimally invasive method for removal of renal calculi, was initially started in the 1950s but gained popularity about two decades later and has now become standard practice for management. There has been an immense improvement in technique and various guidelines have been established for treatment of renal stones. However, it has its own share of complications which can be attributed to surgical technique as well as anesthesia related complications. PubMed and Google search yielded more than 30 articles describing the different complications seen in this procedure, out of which 15 major articles were selected for writing this review. The aim of this review article is to describe the implications of the complications associated with PCNL related to the anesthesiologist. The anesthesiologist is as much responsible for the management of the patient perioperatively as the surgeon. Therefore, it is mandatory to be familiar with the various complications, some of which may be life threatening and he should be able to manage them efficiently. The paper also analyses the advantages and drawbacks of the available options in anesthesia, that is, general and regional, both of which are employed for PCNL.

Minimally invasive versus conventional large-bore percutaneous nephrolithotomy in the treatment of large-sized renal calculi: Surgeon's preference?

OBJECTIVE

The aim of this study was to compare the efficacy and safety of minimally invasive percutaneous nephrolithotomy (MIP) and conventional percutaneous nephrolithotomy (PCNL) in the treatment of patients with large renal stone burden. MIP has proven its efficacy and safety in the management of small renal calculi. However, conventional PCNL is still considered the standard method for treatment of large renal stones in the upper urinary tract.

MATERIALS AND METHODS

A search of two longitudinal databases in two tertiary referral centres for complex stone disease identified 133 consecutive patients who were treated by either MIP or PCNL for renal stones 20 mm or larger between January 2009 and August 2012. Clinical data and outcome measures of the two methods were compared by Student's t test, chi-squared test or Fisher's exact test. A p value less than 0.05 was considered statistically significant.

RESULTS

Operative time was significantly shorter and hospital stay was significantly longer in conventional PCNL compared to MIP (p = 0.002 and < 0.001, respectively). There were no significant differences in primary stone-free rate or complication rate between the two methods. Only higher graded complications (above Clavien grade II) were significantly more common in conventional PCNL (p = 0.02).

CONCLUSION

MIP is equally effective as conventional PCNL in the treatment of large renal calculi. Both methods have a similar complication rate. The shorter operative time in PCNL may be based on the larger diameter and quicker retrieval of large fragments; the longer mean hospital stay may be caused by the handling of the nephrostomy tube. The current data suggest that the choice of the method mainly depends on the surgeon's preference.

Supracostal Approach for PCNL: Is 10th and 11th Intercostal Space Safe According to Clavien Classification System?

The purpose of this study was to evaluate the success and morbidity of percutaneous nephrolithotomy (PCNL) performed through the 11th and 10th intercostal space. Between March 2005 and February 2012, 612 patients underwent PCNL, 243 of whom had a supracostal access. The interspace between the 11th and 12th rib was used in 204 cases (group 1) and between the 10th and 11th interspaces in 39 cases (group 2). PCNL was performed using standard supracostal technique in all patients. The operative time, success rate, hospital stay, and complications according to the modified Clavien classification were compared between group 1 and group 2. The stone-free rate was 86.8% in group 1 and 84.6% in group 2 after one session of PCNL. Auxiliary procedures consisting of ureterorenoscopy (URS) and shock wave lithotripsy (SWL) were required in 5 and 7 patients, respectively, in group 1; and in 1 patient each in group 2 . After the auxiliary procedures, stone-free rates increased to 92.6% in group 1 and 89.7% in group 2. A total of 74 (30.4%) complications were documented in the 2 groups according to modified Clavien classification. Grade-I complications were recorded in 20 (8.2%), grade-II in 38 (15.6%), grade-IIIa in 13 (5.3%), and grade-IIIb in 2 (0.8%) patients; grade-IVa was recorded in 1 (0.4%) patient. There were no grade-IVb or grade-V complications. Overall complication rate was 30.9% in group 1 and 28.2% in group 2. Supracostal PCNL in selected cases is effective and safe with acceptable complications. The modified Clavien system provides a standardized grading system for complications of PCNL.

Study of predictive factors affecting the prolonged urinary leakage after percutaneous nephrolithotomy

Objective:

To evaluate the factors that may influence the prolonged urinary leakage following percutaneous nephrolithotomy (PCNL).

Materials and Methods:

A total of 936 consecutive patients underwent PCNL during the study period from April 2013 to December 2014 at our center, and data were recorded prospectively. Patients who required stage PCNL, chronic renal failure and diabetic patients, concurrent ureteric stone and patients in whom double-J stent was placed because of ureteropelvic injury, or pelvicalyceal extravasation were excluded from the study. After exclusion, 576 patients were included in the study. The predictive factors that may lead to prolonged urinary leakage after PCNL were broadly categorized into patient-related factors and procedure-related factors. Patients were divided into two groups: Group 1 (n = 32) – Required double-J stent placement due to prolonged urinary leakage (>48 h) after removal of the nephrostomy tube. Group 2 (n = 544) – Did not require double-J stent placement.

Results:

Patient-related factors such as stone complexity, grade of hydronephrosis, renal parenchymal thickness in access line, and intra-parenchymal renal pelvis were most important factors for prolonged urinary leakage (P < 0.05, P < 0.05, P < 0.05, and P < 0.05, respectively), while procedure-related factors such as multiple punctures, surgeon's experience, and residual stones were most important factors for prolonged urinary leakage (P < 0.05, P < 0.05, and P < 0.05, respectively).

Conclusion:

In the present study, several factors appear to affect post-PCNL prolonged urinary leakage. We suggest that patients who are at increased risk of prolonged urinary leakage double-J stent should be placed at the end of PCNL procedure.

Percutaneous nephrolithotomy in pediatric age group: Assessment of effectiveness and complications

Management of kidney stone disease in pediatric population is a challenging condition in urology practice. While the incidence of kidney stone is increasing in those group, technological innovations have conrtibuted to the development of minimally invasive treatment of urinary stone disease such as mini-percutenous nephrolitotomy (mini-PCNL), micro-PCNL, ultra mini-PCNL. In this review we tried to evaluate the effect of new teratment techniques on pediatric kidney stones.

Comparison of minimally invasive percutaneous nephrolithotomy and flexible ureteroscopy for the treatment of intermediate proximal ureteral and renal stones in the elderly

The aim of this study is to compare the outcomes of flexible ureteroscopy (fURS) and minimally invasive percutaneous nephrolithotomy (mPNL) for the treatment of renal and/or proximal ureteral stones sized 1-2 cm in the elderly (≥60 years). Between January 2010 and March 2015, 184 consecutive mPNL and fURS were performed to treat intermediate renal and/or proximal ureteral stones in geriatric patients. The records were retrospectively reviewed and outcomes were compared. Although no significant difference was found in the complication rate between two groups, a statistical trend (p = 0.059) in favor of fURS was observed. In addition, multivariate analysis demonstrated that mPNL, preoperative positive urine culture and lower hemoglobin were independent risk factors for postoperative complication (p = 0.016, p = 0.021, p = 0.001, respectively). And fURS was significantly associated with less hemoglobin drop, red blood cell transfusion, analgesics requirement, postoperative hospital duration, and charges of laboratory tests, medical examinations and medications (p = 0.019, p = 0.037, p = 0.006, p = 0.000 and p = 0.007, p = 0.000, p = 0.000, p = 0.001, respectively), while higher costs of operations (p = 0.008). Receiver operating characteristic curve suggested a preoperative hemoglobin of 106.5 g/L as the threshold for predicting red blood cell transfusion after mPNL. The overall one-session stone-free rate of fURS at 1 month was lower (p = 0.006), while it was similar for solitary stone between two groups. Comorbidity and previous stone surgery did not affect postoperative complication and stone-free rate. This study shows that mPNL is more effective for multiple stones, but fURS is associated with potentially less complications and postoperative hospital stay. Furthermore, preoperative hemoglobin level and urine culture can be used to predict postoperative complication risk and they may be helpful in choosing treatment methods for the elderly.

Value of Computed Tomography for Predicting the Outcome After Percutaneous Nephrolithotomy

Introduction

Computerized tomography of the urinary tract (CT-UT) has been established as the diagnostic procedure of choice for urinary stones. This study aimed to evaluate its role in predicting the outcome of percutaneous nephrolithotomy (PCNL) in terms of stone free rate and residual fragments.

Method

This prospective cohort study was conducted on 34 patients in the Urology Department of Theodor Bilharz Research Institute from January 2013 to March 2014. The patients who had large and/or multiple renal stones, including staghorn stones, in 19 renal units scheduled for PCNL were included in this study. All had a pre-operative CT-UT to determine the stones’ characteristics and renal anatomy. CT-UT, together with a kidney-Ureter-Bladder (KUB) film, was taken on the first post-operative day. The data were analyzed by SPSS version 17 using independent-samples t-test and the chi-squared test.

Results

CT-UT showed a statistical significant sensitivity in detecting residual fragments over standard KUB, yet this significance was lost when corrected to significant residual. Stone size and density were independent factors for the presence of residual stones.

Conclusion

CT-UT post PCNL was sensitive to detect residual fragments, yet it showed no superiority over standard KUB in detecting significant residual.

Prospective Outcomes of Ultra Mini Percutaneous Nephrolithotomy: A Consecutive Cohort Study

PURPOSE

Ultra mini percutaneous nephrolithotomy is a less invasive technique of percutaneous nephrolithotomy to treat small to medium sized calculi.

MATERIALS AND METHODS

We prospectively evaluated the outcomes of ultra mini percutaneous nephrolithotomy in a single surgeon, consecutive cohort study. Data on 94 patients who underwent ultra mini percutaneous nephrolithotomy were collected.

RESULTS

Mean ± SD calculus size was 15.9 ± 4.5 mm and mean density was 1,106 ± 167 HU. Access was achieved via the upper pole in 8 cases, interpolar in 33 and lower pole in 54. Mean operative time was 54 minutes (range 28 to 120). Mean hemoglobin loss was 0.81 gm/dl and the mean creatinine increase was 0.05 mg/dl. There were no transfusions or kidney injuries. Grade I and IIIb complications were observed in 4 and 1 patients, respectively. The most serious complication was a perinephric collection. Postoperatively oral analgesia was sufficient in 86 patients (91%). Mean length of stay was 38.2 ± 15.9 hours. Nephrostomy drainage was used in 13 patients while 7 (7%) required a stent for 1 week. Intraoperatively 99% of renal units were stone free (absence of detectable calculi) on fluoroscopy, and 74% and 81% were stone free on day 1 postoperative ultrasound and 1-month computerized tomography, respectively. The 10 to 20 mm stones showed less bleeding, shorter operative time and a significantly lower requirement for nephrostomy or a Double-J(®) stent.

CONCLUSIONS

Ultra mini percutaneous nephrolithotomy appears to be effective and safe with a short length of stay. It may be a valuable addition to the armamentarium to treat 10 to 20 mm calculi in patients who wish to avoid routine nephrostomy or stents. Randomized, controlled trials are required.

Value of preoperative stone scoring systems in predicting the results of percutaneous nephrolithotomy

INTRODUCTION

Guy's Stone Score and S.T.O.N.E. Nephrolithometry nomograms have been introduced for systematic and quantitative assessment of kidney stones. The aim of this study was to reveal the value of two scorings systems, Guy and S.T.O.N.E, most frequently used for predicting postoperative stone-free status prior to Percutaneous Nephrolithotomy (PCNL), in the prediction of postoperative results of PCNL.

MATERIAL AND METHODS

We retrospectively examined patients who underwent PCNL. Preoperative abdominopelvic computerized tomography images of these patients were reviewed and scored according to the Guy and S.T.O.N.E. systems. The relationship between the Guy and S.T.O.N.E. scores, and their postoperative stone-free status, complications based on Clavien system, operation time, fluoroscopy time and period of hospitalization was compared.

RESULTS

We identified a total of 102 patients who underwent PCNL between 2010 and 2014, having met the inclusion criteria. The relationships between the total S.T.O.N.E score and Clavien score (p <0.001); time of operation (p = 0.012) and stone-free status (p <0.001); Guy stone score and Clavien score (p <0.001); and period of hospitalization (p <0.001) and time of operation (p <0.001) were found to be statistically significant. There was no statistically significant relationship between Guy score and stone-free status and no statistically significant relationship was found between fluoroscopy time and both stone scoring systems.

CONCLUSIONS

Guy and S.T.O.N.E. scoring systems may be used as effective instruments particularly for predicting postoperative complications.

Ultra-mini-percutaneous nephrolithotomy in pediatric nephrolithiasis: both low pressure and high efficiency

INTRODUCTION

The management of urolithiasis in children differs from adults because of anatomic and metabolic abnormalities. At present, various minimally invasive and invasive treatment strategies have been recommended to treat urinary tract Stones, including shock wave lithotripsy (SWL), standard percutaneous nephrolithotomy (PNL), mini-PNL, retrograde intrarenal surgery (RIRS), micro-PNL, and a new technique termed ultra-mini PNL (UMP). UMP is a new method for the treatment of kidney stones. The main difference between UMP and standard PNL or mini-PNL lies in the small access sheath and in its design. A 9.5F pediatric compact cystoscope was used (Figure). A major advantage of UMP is that it provides similar stone-free rates when compared with standard PNL, with lower intrarenal pressure than micro-PNL.

OBJECTIVE

The aim of the study was to determine the applicability and safety of UMP in the treatment of pediatric kidney stones.

PATIENTS AND METHODS

We retrospectively reviewed the files of 39 kidney stones in children who had undergone UMP between May 2011 and October 2014. The indications for UMP included stones resistant to SWL, stones requiring repeated sessions of SWL, and stones size larger than 20 mm.

RESULTS

The study included 17 females and 22 males, with a mean age of 5.8 ± 4.6 years. The mean hemoglobin loss was 0.9 ± 0.6 mg/dL and none of the patients required a blood transfusion. The complication rate of the PNL procedure was 15.3% (n = 6). Complete clearance was achieved in 32 patients (82%) with UMP monotherapy, which increased to 34% (87.1%) 4 weeks after the operation.

DISCUSSION

Management of urolithiasis necessitates a balance between stone clearance and morbidity related to the procedure. SWL often leads to persistent residual stones. The developing RIRS can minimize the risks associated with bleeding and visceral injury, but sometimes the abnormal pelvicaliceal anatomy and poor imaging of the flexible ureteroscopy may impact its success rate and applications. It has been reported that PNL can be performed safely and effectively to achieve a higher stone-free rate; however, it has serious complications such as bleeding that requires blood transfusion in 11-14% of the cases with increased risk of kidney loss. The recent development of smaller sheaths allows tract formation with minimal damage to the renal parenchyma, thereby reducing procedure-related morbidity without diminishing its therapeutic efficacy.

CONCLUSION

The most important advantage of this surgical technique that has been developed is similar stone-free rates to standard PNL and lower intrarenal pressure than micro-PNL. Our experience supports that UMP is safe and effective for the management of renal stones in children.

Laparoscopic pyelolithotomy: An emerging tool for complex staghorn nephrolithiasis in high-risk patients

Objectives

To evaluate the effectiveness of laparoscopic pyelolithotomy (LP) for staghorn stones (>3–4 cm) in patients with chronic liver disease or coronary artery disease.

Patients and methods

In all, 49 patients underwent LP; they were divided into four groups, with stones in group 1 in the renal pelvis only, in group 2 in the renal pelvis and one calyx, in group 3 in the renal pelvis and two calyces, and in group 4, in the renal pelvis and more than two calyces. Patient demography, stone characteristics, surgical outcomes and complications were evaluated.

Results

The mean stone-free rate in one session was 90% among all groups. The mean (SD) stone size was 4.27 (1.72) cm. The stone-free rate decreased with greater stone burden, but the operative time, estimated blood loss and need for ancillary procedures increased with stone burden. No blood transfusion was required and one patient each in groups 2 and 4 had a urine leak.

Conclusion

LP provides acceptable results in complex cases for managing renal stone disease with a larger stone burden in high-risk situations.

Applicability of the Clavien-Dindo grading system for assessing the postoperative complications of endoscopic surgery for nephrolithiasis: a critical review

OBJECTIVE

Adaptation of the Clavien-Dindo classification for assessing the severity of complications following the endoscopic treatment of nephrolithiasis and evaluation of its versatility and objectivity.

MATERIAL AND METHODS

We retrospectively reviewed the medical records of 1027 patients who presented stones located in upper urinary tract (597 males, 58.1% and 430 females, 41.9%), mean age 38.9±15.6 (range, 4 to 84) years. The age ranged from 4 to 15 years in 46 (4.5%) of the patients. The mean size of the stones was 30.3±0.6 (range, 3 to 150) mm. Percutaneous nephrolithotomy (PNL) and ureteroscopy (URS) were performed by three experienced surgeons, PNL with the patients in the prone position. Fragmentation of stones was carried out using a pneumatic lithotripter. The outcomes were compared using Fisher's exact test and Student's t-test. The Clavien-Dindo grading system was used.

RESULTS

We observed 195 (19.0%) patients who presented a total of 250 complications during the postoperative period. Additional interventions have been performed to eliminate 74 complications: 41 under general anesthesia and 33 without it. "Stone free status" was reached in 879 (85.6%) patients. Postoperative complications were assessed using Clavien grading system: Grade I for 64 complications (6.2%); Grade II for 111 (10.8%); Grade IIIa for 33 (3.2%); Grade IIIb for 39 (3.8%); Grade IVa for 3 (0.3%); Grade IVb for 0; and Grade V for 0.

CONCLUSION

There is no ideal classification system for assessing the severity of surgical complications. The Clavien-Dindo classification can be adapted to assess the severity of postoperative complications following endoscopic procedures for nephrolithiasis if certain corrections are made.

Modular training for percutaneous nephrolithotripsy: The safe way to go

Objectives should be describe a modular training scheme (MTS) which aims to provide training in percutaneous nephrolithotripsy (PCNL) and ensure the safety of the patients.

Subjects and methods

Two trainees with no experience in PCNL attended the MTS under the supervision of an experienced mentor. The MTS included five modules, comprising an initial animal laboratory course (using pigs), to acquire basic skills (Module 1), and Modules 2–5 included making the puncture, tract dilatation, single-stone and large-stone management in clinical cases, respectively. Each participant progressed from one module to the next under constant mentoring and evaluation by the mentor. When the trainees completed the MTS they proceeded to perform 60 PCNL procedures independently while the mentor performed 25 for comparison purposes. A global rating scale was used for the objective evaluation of the trainees. Peri-operative variables were recorded and statistically compared as appropriate. Statistical significance was defined as P < 0.05.

Results

One pig and 16 patients, and two pigs and 22 patients, were necessary to complete the MTS by each subject. There were no significant differences among the characteristics of the independently performed operations. The duration of surgery and fluoroscopy achieved a plateau similar to those of the mentor after ≈ 30 patients. The decrease in haemoglobin level, stone-free and complication rates in the patients were similar among the two trainees and the mentor. The complication rate of the trainees and the mentor never exceeded 13.3%.

Conclusion

The MTS successfully combined animal and stepwise clinical training based on a standardised technique and objective evaluation.

Evaluating the Learning Curve for Percutaneous Nephrolithotomy under Total Ultrasound Guidance

Objectives

To investigate the learning curve of percutaneous nephrolithotomy under total ultrasound guidance.

Methods

One hundred and twenty consecutive PCNL operations under total ultrasound guidance performed by a novice surgeon in a tertiary referral center were studied. Operations were analyzed in cohorts of 15 to determine when a plateau was reached for the variables such as operation duration, ultrasound screening time, tract dilation time, stone-free rate and complication rate. Comparison was made with the results of a surgeon who had performed more than 1000 PCNLs. Fluoroscopy was not used at all during procedure.

Results

The mean operation time dropped from 82.5 min for the first 15 patients to a mean of 64.7 min for cases 46 through 60(P = 0.047). The ultrasound screening time was a peak of 6.4 min in the first 15 cases, whereas it dropped to a mean of 3.9 min for cases 46 through 60(P = 0.01). The tract dilation time dropped from 4.9 min for the first 15 patients to a mean of 3.8 min for cases 46 through 60(P = 0.036). The senior surgeon had a mean operating time, screening time and tract dilation time equivalent to those of the novice surgeon after 60 cases. There was no significant difference in stone free rate and complication rate.

Conclusions

The competence of ultrasound guided PCNL is reached after 60 cases with good stone free rate and without major complications.