Erhan Sari

Factors Affecting Bleeding During Percutaneous Nephrolithotomy: Single Surgeon Experience

PURPOSE To investigate variables that affect bleeding during percutaneous nephrolithotomy (PCNL), focusing on the experience of a single surgeon. PATIENTS AND METHODS The records of 649 PCNL procedures that were performed by the same surgeon were reviewed retrospectively. The effect of surgical experience; patient and stone-related factors, including age, sex, hypertension, and diabetes, serum creatinine level, history of ipsilateral renal procedures, stone surface area and type, degree of hydronephrosis, preoperative hemoglobin level; operative factors, such as the calix of puncture, number of accesses, operative time; and intraoperative complications, such as pelvicaliceal system perforation on bleeding (described as decrease in hemoglobin level and need for blood transfusion), were investigated. For statistical assessment, univariate analyses and multivariate stepwise regression analyses were used. RESULTS A 92.3% success rate was achieved after one session PCNL. The overall blood transfusion rate was 10.8%. The number of accesses, stone type, diabetes, preoperative hemoglobin level, and operative time were the most important factors for blood transfusion requirement. In the receiver operating characteristic curve, the best cutoff point of operative time was 58 minutes for the blood transfusion requirement. Multivariate stepwise regression analyses showed that there was an association between diabetes, operative time, number of accesses, and stone type with the decrease in hemoglobin levels. No correlation between surgical experience and decrease in hemoglobin level as well as blood transfusion necessity was found. CONCLUSIONS Depending on the results achieved by a single surgeon, multiple access tracts, staghorn calculi, presence of diabetes, and prolonged operative time, but not surgical experience, significantly increased blood loss during PCNL.

Impact of Percutaneous Access Point Number and Location on Complication and Success Rates in Percutaneous Nephrolithotomy

Objectives: Percutaneous nephrolithotomy (PNL) is sometimes associated with complications, especially in patients with complex stones. Herein, we review our experience with PNL to determine the impact of percutaneous access number and location on success and complication rates. Patients and Methods: During a 2-year period, a total of 275 patients with a mean age of 42.3 ± 14.8 (range: 13–75) years underwent PNL. Stones were classified as simple in 51.6%, and complex (staghorn calculi or renal pelvis stones coexisting with caliceal stones) in 48.4%. Percutaneous access was done under C-armed fluoroscopy and the tract was formed with a high-pressure balloon dilation system. One single percutaneous access was sufficient in 210 (76.4%), while 2 accesses were utilized in 44 (16%), and ≧3 accesses in 21 cases (7.6%). Supracostal access was performed in 23 (8.4%) patients. Results: An overall success rate of 94.9% was achieved. Stone location, but not the access point location, was the major determinant for success, which was 99.3 and 90.2% in patients with simple and complex stones, respectively (p < 0.01). Significant complications included bleeding necessitating blood transfusion in 28 (10.2%), and hydropneumothorax in 2 (0.7%) patients. Bleeding was observed in 39.1 and 7.5% of patients managed with supracostal access, and subcostal access, respectively (p < 0.01). An increased number of access points significantly augmented the risk for bleeding. Bleeding was encountered in 7.6% of patients managed with 1 percutaneous access point, and in 18.5% of cases managed with ≧2 access points (p < 0.05). Hydropneumothorax occurred in patients with supracostal access. Conclusion: Supracostal access as well as multiple punctures may be needed especially in the management of complex stones, and the need for multiple access points and supracostal access significantly increases complication rates.

A prospective, randomized trial of management for asymptomatic lower pole calculi.

PURPOSE We determined the natural course and compared the deleterious effects in kidneys of shock wave lithotripsy, percutaneous nephrolithotomy and observation for asymptomatic lower caliceal stones. MATERIALS AND METHODS Between April 2007 and August 2008 patients with asymptomatic lower caliceal calculi were enrolled in the study. To assess stone status noncontrast abdominal helical computerized tomography was done 3 and 12 months after intervention. All patients were evaluated by dimercapto-succinic acid renal scintigraphy 6 weeks and 12 months after intervention. RESULTS A total of 94 patients were prospectively randomized to percutaneous nephrolithotomy (31), shock wave lithotripsy (31) and observation (32). Mean +/- SD followup was 19.3 +/- 5 months (range 12 to 29). In the percutaneous nephrolithotomy group all patients were stone-free at month 12. Scintigraphy revealed a scar in 1 patient (3.2%) on month 3 followup imaging. In the shock wave lithotripsy group the stone-free rate was 54.8%. Scintigraphy revealed scarring in 5 patients (16.1%). In the observation group 7 patients (18.7%) required intervention during followup. Median time to intervention was 22.5 +/- 3.7 months (range 18 to 26). One patient (3.1%) had spontaneous stone passage. Scintigraphy did not reveal scarring in any patient. CONCLUSIONS Stone related events were noted in more than 20% of patients with asymptomatic lower caliceal stones observed expectantly. To manage lower caliceal stones percutaneous nephrolithotomy has a significantly higher stone-free rate with less renal scarring than shock wave lithotripsy. Thus, patients with asymptomatic lower caliceal stones must be informed in detail about all management options, especially focusing on percutaneous nephrolithotomy with its outstanding outcome.

Comparison of Outcomes After Percutaneous Nephrolithotomy of Staghorn Calculi in Those with Single and Multiple Accesses

PURPOSE To analyze the early outcome after single tract vs multiple tracts percutaneous nephrolithotomy (PCNL) in the management of staghorn calculi. PATIENTS AND METHODS The records of 413 patients with staghorn calculi (223 [54%] had complete and 190 [46%] had partial) who underwent PCNL were reviewed retrospectively. A total of 244 (59%) patients were managed by single access (group 1); meanwhile, multiple accesses were necessary in 169 (41%) patients (group 2). Both groups were compared in terms of perioperative findings and postoperative outcomes. Patients and stone-related factors affecting the number of accesses performed were analyzed. RESULTS The mean number of percutaneous accesses was 2.42 +/- 0.74 (range 2-6) in group 2. Mean durations of fluoroscopy screening time and operative time were significantly longer in group 2 (P = 0.002, P < 0.0001, respectively). Supracostal access was necessary in 30.7% in group 2 and in 6.9% in group 1 (P = 0.001). Success was achieved in 70.1% in group 1 and in 81.1% for group 2 after one session of PCNL (P = 0.012). The most common complication was bleeding for both groups, and it was higher in group 2 (P < 0.0001). The mean preoperative and postoperative creatinine concentrations were 1.03 mg/dL and 1.08 mg/dL in group 1, and 0.9 mg/dL and 1.03 mg/dL in group 2, respectively. The mean changes in creatinine values were not statistically significant between the groups (P = 0.16). CONCLUSIONS The impact of PCNL using either single or multiple access tracts on renal function is similar and of a temporary nature. PCNL with multiple accesses is a highly successful alternative with considerable complication rates in the management of staghorn calculi.

Tubeless Procedure is Most Important Factor in Reducing Length of Hospitalization After Percutaneous Nephrolithotomy: Results of Univariable and Multivariable Models

OBJECTIVES To evaluate the effects of kidney stones and patient-related parameters on the length of hospitalization (LOH), which is one important factor affecting the cost effectiveness of percutaneous nephrolithotomy (PCNL). Recently, increases in healthcare costs have highlighted the importance of evaluating the cost effectiveness of a treatment as much as its efficacy. MATERIAL AND METHOD During an 8-year period, the records of 1669 patients with renal calculi who underwent PCNL were reviewed retrospectively. Eleven patients with urosepsis were excluded from the present study. A total of 1658 patients were categorized into 2 groups (group 1 = ≤2 days; group 2 = >2 days) according to the median LOH (median = 2 days). Multivariate binary logistic regression analysis was used to detect the effects of independent variables, including the patient age, gender, body mass index, history of extracorporeal shock wave lithotripsy or open surgery, stone size and opacity, presence of hydronephrosis, and localization and number of accesses, on the LOH after PNL. RESULTS Overall success was achieved in 86.2% of cases after one session of PCNL. The mean length of hospitalization was 2.89 ± 1.66 days (range, 1-21). According to the outcome of the multivariate analysis, diabetes (P = .0001, OR = 1.67), impaired kidney function (P = .03, OR = 1.64), stone size (P = .031, OR = 1.31), number of accesses (P = .001, OR = 1.59), intercostal access (P = .001, OR = 1.79), and tubeless procedure (P = .0001, OR = 0.23) were variables influencing LOH. CONCLUSIONS The presence of diabetes, a large stone burden, intercostals access, multiple accesses, and impaired kidney function prolong the LOH after PCNL. The use of the tubeless procedure was able to diminish the LOH.

Factors Affecting the Fluoroscopic Screening Time During Percutaneous Nephrolithotomy

PURPOSE Percutaneous nephrolithotomy (PNL) is established in urology practice with routine use of fluoroscopic guidance. Herein, we retrospectively evaluated the potential factors affecting the fluoroscopic screening time (FST) during PNL. MATERIALS AND METHODS A total of 282 patients with documented FST in detail during PNL performed by one surgeon were enrolled in this study. In all cases, PNL was performed on patients in prone position under C-armed fluoroscopy unit. The correlation between the FST and patient and also stone factors, including body mass index (BMI), previous open renal surgery, characteristics and size of the stone, and presence of hydronephrosis, as well as procedural factors such as percutaneous access number and location and operation time were analyzed. RESULTS The mean age of the patients was 43 +/- 14.7 (range: 18-67) years. The mean operation time was 78.9 +/- 22.0 (range: 45-150) minutes, and the mean FST was 10.19 +/- 6.3 (range: 3-50) minutes. The mean stone size was 8.46 +/- 5.11 cm(2) (range: 2-30). The FST was significantly prolonged in patients with increased stone burden (p = 0.001) and necessitating multiple accesses procedures (p = 0.007). However, BMI of the patient, stone configuration, degree of hydronephrosis, history of open renal surgery, and access location did not have an impact on FST (p > 0.05). CONCLUSION In patients with large stones necessitating multiple accesses, FST is significantly prolonged; therefore, they have to be managed by experienced surgeons to diminish the radiation exposure. However, BMI, stone configuration, presence of hydronephrosis, history of open renal surgery, and access location did not have effect on FST in our study.

Does Previous Extracorporeal Shock Wave Lithotripsy Affect the Performance and Outcome of Percutaneous Nephrolithotomy

PURPOSE ESWL and percutaneous nephrolithotomy are the primary treatment modalities for kidney stones. Furthermore, percutaneous nephrolithotomy is first line treatment when ESWL fails. We assessed how previous ESWL affects the performance and outcome of percutaneous nephrolithotomy. MATERIALS AND METHODS A total of 1,008 patients underwent percutaneous nephrolithotomy between 2002 and 2007, of whom 230 (22.8%) had a recent history of failed ESWL. Patient characteristics, operative findings, success and complication rates in patients with and without a history of ESWL were analyzed and compared. RESULTS In the post-ESWL group mean stone size was significantly lower and the mean +/- SD interval between the last ESWL session and percutaneous nephrolithotomy was 3.4 +/- 2.1 months (range 1 to 12). Mean operative time and fluoroscopic screening time were similar in the 2 groups (p >0.05). However, mean operative time per cm(2) stone and fluoroscopic screening time per cm(2) stone were significantly prolonged in the post-ESWL group (p <0.05). At a mean followup of 5.6 +/- 1.2 months (range 3 to 6) an overall success rate of 89% was achieved. Success and complication rates were comparable in the 2 groups. CONCLUSIONS Although similar success and complication rates were achieved with percutaneous nephrolithotomy after failed ESWL, percutaneous nephrolithotomy is usually more difficult with prolonged operative time and fluoroscopic screening time per cm(2) stone due to the tissue effects of ESWL and scattered stone fragments in the pelvicaliceal system.

Does Pelvicaliceal System Anatomy Affect Success of Percutaneous Nephrolithotomy

OBJECTIVE To investigate the effect of the pelvicaliceal system (PCS) anatomy on the percutaneous nephrolithotomy (PCNL) success rate. Although the caliceal anatomy is effective for stone clearance after shock wave lithotripsy and retrograde intrarenal lithotripsy, the effect of the caliceal anatomy after PCNL has not been evaluated to date. METHODS A total of 498 patients who had undergone PCNL and preoperative intravenous urography were enrolled in our study. Kidney-related anatomic factors, such as the PCS surface area and type, degree of hydronephrosis, infundibulopelvic angle, upper-lower calix angle, infundibular length, and infundibular width were calculated using intravenous urography. The association between the PCNL success rate and kidney-related anatomic factors was retrospectively analyzed using chi-square tests, Fishers exact test, Mann-Whitney U test, and forward stepwise regression analysis. RESULTS A success rate of 78.1% was achieved. No difference was seen the success rates among the PCS types. The mean PCS surface area was 20.1 ± 9.7 cm(2) in patients with successful outcomes and 24.5 ± 10.2 cm(2) in patients with remaining stones (P = .001). The mean infundibulopelvic angle, upper-lower calix angle, infundibular length, and infundibular width were similar in both groups. Multivariate binary logistic regression analysis showed that stone configuration and PCS surface area were independent factors affecting the PCNL success rates. CONCLUSION The results of our study have shown that the PCS surface area is the only anatomic factor that affects the PCNL success rate and patients with a PCS surface area <20.5 cm(2) have greater PCNL success.

Factors Affecting Kidney Function and Stone Recurrence Rate After Percutaneous Nephrolithotomy for Staghorn Calculi: Outcomes of a Long-Term Followup

PURPOSE There are few studies of the long-term outcome of percutaneous nephrolithotomy for staghorn calculi. We report the long-term outcome of percutaneous nephrolithotomy in patients with staghorn calculi. MATERIAL AND METHODS A total of 265 study patients (272 renal units) were followed in the long term for greater than 12 months. The estimated glomerular filtration rate was calculated using the 4-variable modification of diet in renal disease equation. Cases were staged for chronic kidney disease by National Kidney Foundation guidelines. The impact of patient and procedure related factors on renal function as well as stone recurrence was analyzed retrospectively. RESULTS At a mean ± SD followup of 37.3 ± 25.4 months the chronic kidney disease stage classification was maintained in 177 patients (66.8%) while the classification of 34 (12.8%) and 54 (20.4%) had improved and deteriorated, respectively. Multivariate analysis revealed that an immediate postoperative change in the estimated glomerular filtration rate was the only factor predicting a change in renal function in the long term. Stones recurred in 73 of the 234 kidneys (31.2%) that were stone free 3 months after percutaneous nephrolithotomy. Stone size increased in 24 of the 38 kidneys (63.2%) with residual stones after intervention. Recurrent urinary infections during followup and diabetes were associated with stone recurrence and residual stone enlargement. CONCLUSIONS In almost 80% of patients with staghorn stones renal function was improved or maintained after percutaneous nephrolithotomy, as documented during long-term followup. Stones recurred in a third of the patients with staghorn calculi.

Percutaneous nephrolithotomy in horseshoe kidneys: factors affecting stone-free rate.

PURPOSE We report a 2-center study of factors affecting the stone-free rate after percutaneous nephrolithotomy in horseshoe kidneys. MATERIALS AND METHODS The postoperative stone-free rate after percutaneous nephrolithotomy was evaluated in 47 male and 11 female patients with horseshoe kidneys. All data were collected prospectively. Patient and procedure related factors predicting the stone-free rate were analyzed by univariate and multivariate tests. RESULTS The mean ± SD stone burden was 7.62 ± 7.18 cm(2) (range 1 to 45) and the stone was larger than 10 cm(2) in 14 patients (24.1%). Complex stones and staghorn stones were present in 21 (36.2%) and 19 patients (32.7%), respectively. The overall stone-free rate was 65.5%. Complex stones (p = 0.01), stone burden greater than 5 cm(2) (p = 0.013), stone burden greater than 10 cm(2) (p = 0.012), multiple stones (p = 0.006) and staghorn stones (p <0.001) were related to adverse outcomes on univariate analysis. Logistic regression analysis revealed that staghorn calculi was the only factor that significantly predicted the stone-free rate (p = 0.002). A patient with staghorn calculi in the horseshoe kidney was 45 times more likely to have a lower stone-free rate after percutaneous nephrolithotomy than a patient without staghorn calculi in the horseshoe kidney. CONCLUSIONS Stone parameters are important when treating calculi in horseshoe kidneys. Staghorn calculi are associated with a lower stone-free rate after percutaneous nephrolithotomy.