Nefrolitotricia percutánea ambulatoria: nuestra experiencia en 156 casos / Ambulatory Percutaneous Nephrolithotomy: Our experience in 156 cases

OBJETIVOS: analizar y presentar nuestros resultados en el tratamiento de la litiasis renal mediante Nefrolitotricia Percutánea (NLP) ambulatoria en un mismo centro. MATERIALES Y MÉTODOS: entre agosto de 2013 y mayo de 2017 se realizó una recolección prospectiva de datos de los pacientes sometidos a NLP ambulatoria tubeless con catéter doble J o totally tubeless por litiasis renal. Se excluyeron aquellos pacientes con score de ASA >3. Se analizaron los datos preoperatorios, intra- y posoperatorios. Se clasificaron las complicaciones de acuerdo con el sistema de Clavien modificado. Se compararon los valores de hematocrito, hemoglobina, creatininemia y uremia pre- y posoperatoria a las 48 horas. RESULTADOS: en total, se operaron 156 pacientes, a los cuales se les dio el alta el mismo día de la cirugía. La suma de los diámetros máximos de las litiasis, en promedio, fue de 26,6 mm, 32 casos de litiasis coraliforme. La posición más utilizada fue la ventral, con un tiempo promedio de cirugía de 50 minutos. Se realizó NLP tubeless en 125 pacientes y totally tubeless en 29 casos. A 40 pacientes se les colocó un tapón de Surgicel en el tracto de acceso percutáneo. La tasa libre de cálculos fue del 84%, y en pacientes con litiasis coraliforme fue del 53%. No hubo complicaciones intraoperatorias y el 80% de los pacientes no presentó complicaciones. La tasa de reinternación fue del 3%. Si bien se hallaron diferencias significativas entre los valores pre- y posoperatorios de hematocrito y hemoglobina (40% y 13,3 g/dl vs. 39% y 12,8 g/dl; p=0,0001 y 0,0001, respectivamente), estas no fueron clínicamente significativas y solamente un paciente requirió de transfusión de sangre (0,6%). CONCLUSIONES: en nuestra experiencia, la NLP ambulatoria fue segura, con tasas libres de cálculos y complicaciones similares a las realizadas con internación.

OBJECTIVES: To assess the safety and feasibility of ambulatory percutaneous nephrolithotomy (PCNL) at a single institution. METHODS: Data collected prospectively of patients submit for ambulatory PCNL tubeless or totally tubeless between August 2013 and May 2017 were review. Exclusion criteria were patients with ASA score >3. Preoperative, intraoperative, and postoperative data were collected. Complications were classified using the Clavien sistem modified for PCNL. Properative and 48hs postoperative value of hematocrit, hemoglobin, creatininemia and uremia were compare. RESULTS: One hundred and fifty five patients underwent ambulatory PCNL. All patients were discharge the same day of surgery. The median of the sum of the maximum stone diameter was 26,6mm, 32 patients had staghorn calculus. We performed the majority of the surgerys in ventral position with a median time of 50 minutes. One hundred and twenty five patients underwent tubeless PCNL and totally tubeless 29 patients. In 40 cases we used Surgicel for sealing the percutaneous tract. Overall stone-free rate was 84% and 53% in staghorn cases. There were no intraoperative complications and 80% of the patients did not have any complications. Readmission rate was 3%. There was a significant decrease in the postoperative hematocrit and hemoglobin level (40% y 13,3 g/dl vs. 39% y 12,8 g/dl; p=0,0001 y 0,0001), this was not clinically significant. Only one patient required blood transfusion (0,6%). CONCLUSION: Ambulatory PCNL is safe with a stone-free rate, readmisions and complications similar to standard PCNL.

Factors affecting fluoroscopy time during percutaneous nephrolithotomy: Impact of stone volume distribution in renal collecting system

ABSTRACT Purpose: To identify the factors increased fluoroscopy time during percutaneous nephrolithotomy and investigate the relationship between the 3D segmentation volume ratio of stone to renal collecting system and fluoroscopy time. Materials and Methods: Data from 102 patients who underwent percutaneous nephrolithotomy were analyzed retrospectively. Volume segmentation of both the renal collecting system and stones were obtained from 3D segmentation software with the images on CT data. Analyzed stone volume (ASV), renal collecting system volume (RCSV) measured and the ASV-to-RCSV ratio was calculated. Several parameters were evaluated for their predictive ability with regard to fluoroscopy time. Results: The stone-free rate was 55.9% after the percutaneous nephrolithotomy. Complications occurred in 31(30.4%) patients. The mean fluoroscopy time was 199.4±151.1 seconds. The fluoroscopy time was significantly associated with the ASV-to-RCSV ratio (p<0.001, r=0.614). The single tract was used in 77 (75.5%) cases while multiple tracts were used in 25 (24.5%) cases. Fluoroscopy time was significantly associated with multiple access (p<0.001, r=0.689). On univariate linear regression analysis, longer fluoroscopy time was related with increased stone size, increased stone volume, increased number of access, increased calyx number with stone, increased ASV-to-RCSV, increased operative time and decreased stone essence. On multivariate linear regression analysis, the number of access and the ASV-to-RCSV were independent predictors of fluoroscopy time during percutaneous nephrolithotomy. Conclusions: The distribution of the stone burden volume in the pelvicalyceal system is a significant predictor for prolonged fluoroscopy time during percutaneous nephrolithotomy. Measures to decrease FT could be beneficial in patients with a high ASV-to-RCSV ratio for precise preoperative planning.

Comparison of supine and prone miniaturized percutaneous nephrolithotomy in the treatment of lower pole, middle pole and renal pelvic stones: A matched pair analysis

ABSTRACT Purpose We aimed to compare the outcomes of supine and prone miniaturized percutaneous nephrolithotomy (m-PNL) in the treatment of lower pole, middle pole and renal pelvic stones. Materials and Methods 54 patients who performed supine m-PNL between January 2017 and March 2018 and 498 patients who performed prone m-PNL between April 2015 and January 2018 were included in the study. Of the 498 patients, 108 matching 1: 2 in terms of age, gender, body mass index, American Association of Anesthesiology score, stone size, stone localization and hydronephrosis according to the supine m-PNL group were selected as prone m-PNL group. The patients with solitary kidney, upper pole stone, urinary system anomaly or skeletal malformation and pediatric patients (<18 years old) were excluded from the study. The success was defined as 'complete stone clearance' and was determined according to the 1st month computed tomography. Results The operation time and fluoroscopy time in supine m-PNL was significantly shorter than prone m-PNL group (58.1±45.9 vs. 80.1±40.0 min and 3.0±1.7 min vs. 4.9±4.5 min, p=0.025 and p=0.01, respectively). When post-operative complications were compared according to the modified Clavien-Dindo classification, overall and subgroup complication rates were comparable between groups. There was no significant difference between the groups in terms of the success rates (supine m-PNL; 72.2%, prone m-PNL; 71.3%, p=0.902). Conclusions Supine m-PNL procedure is more advantageous in terms of operation time and fluoroscopy time in the treatment of lower pole, middle pole and renal pelvic stones.

A prospective study assessing feasibility of performing percutaneous nephrolithotomy in chronic kidney disease patients - What factors affect the outcome?

ABSTRACT Objectives To primarily evaluate the functional outcomes of PCNL for bilateral renal calculi/calculi in solitary functioning kidney with Chronic Kidney Disease(CKD). To identify factors affecting the renal replacement therapy following PCNL. Materials and Methods Patients with bilateral renal calculi/calculi in solitary kidney and CKD (eGFR<60/s.creatinine>2) and Good Performance Status [Eastern Cooperative Oncology Group (ECOG): 0-2] were included in the study. Results A total of 60 patients with CKD who had bilateral renal calculi/calculi in solitary functioning kidney underwent PCNL. At 6 months, eGFR improved or stabilized in 45 (75%) patients, while in 15 (25%) patients eGFR deteriorated. A total of 5 (14.28%) and 2 (25%) patients of CKD stage 4 and 5 respectively had improvement in eGFR as well as CKD stage. Fourteen (82.35%), 21 (60%), 3 (37.5%) patients of CKD stage 3, 4, 5 had improvement in eGFR but not significant enough to cause stage migration. Again 3 (17.65%) , 9 ( 40%) and 3 (37.5%) patients of CKD stage 3, 4, 5 had reduction in eGFR but not significant enough to cause stage migration. None of the patients had worsening of CKD stage. Preoperative CKD stage and eGFR were compared with measurements made at the final follow up visit (6 months). Conclusion Our results indicate that most patients of renal calculi with CKD show improvement or stabilization of renal function with aggressive stone removal. Improvement is more in patients who have mild to moderate CKD. Aggressive management of comorbidities, peri-operative UTI and complications may delay or avoid progression of CKD status in such patients.

Retrograde vs. antegrade flexible nephroscopy for detection of residual fragments following PNL: a prospective study with computerized tomography control

ABSTRACT Introduction: The main aim of stone surgery is to establish stone free status. Performing flexible nephroscopy is an effective tool in this manner. The aim of this study was to evaluate the role of retrograde flexible nephroscopy for detection of residual fragments following percutaneous nephrolithotomy (PNL) in comparison with antegrade approach. Materials and Methods: Data of 137 patients underwent ECIRS was collected prospectively. In all cases following stone clearance, collecting system was checked for residual fragments. First antegrade than retrograde flexible nephroscopy was performed and success rates to reach all calices and detection of residual fragments were noted. All patients underwent CT and success rate of antegrade and retrograde approaches were compared. PPV and NPV of retrograde approach to detect residual fragments were calculated. Results: Antegrade and retrograde nephroscopy successfully accessed all of the calices in 101 (73.7%) and 130 (94.9%) patients respectively (p<0.0001). Residual fragments were observed in 18 (13.1%) patients following antegrade flexible nephroscopy. Retrograde approach identified residual stones in 17 more cases. These cases were treated with flexible nephroscopy or secondary percutaneous tract. Postoperative CT revealed residual stones in 10 (7.3%) patients. PPV and NPV of retrograde flexible nephroscopy were 83.3% and 96.2%. Conclusions: Flexible nephroscopy effectively detects residual fragments following PNL. Retrograde approach was more successful than antegrade approach to reach all calices. We recommend performing retrograde flexible nephroscopy following PNL especially in complex cases as it has the potential to increase SFR, decrease the need for second look surgery and unnecessary postoperative imaging.

Tasa libre de litos sin complicación mayor como definición de éxito en nefrolitotomía percutánea / Stone-free rate without major complication as a definition of success in percutaneous nephrolithotomy

Resumen Introducción: El éxito en nefrolitotomía percutánea (NLP) se define como estatus libre de litos, sin embargo, las complicaciones mayores se presentan con alta frecuencia y han sido reportadas como resultado secundario. Objetivo: Presentar una nueva definición de éxito en NLP que comprenda la tasa libre de litos sin complicaciones mayores y una escala de riesgo para predecir este desenlace. Método: Cohorte histórica de pacientes sometidos a NLP. Las variables incluidas fueron edad, sexo, urocultivo, índice de comorbilidad de Charlson (ICC) y lito complejo. Se definió éxito: sin litos, sin o con complicación Clavien ≤ 2; éxito intermedio: con litos sin o con complicación Clavien ≤ 2; fracaso: con o sin litos con complicación Clavien > 2. Se realizó análisis bivariado para identificar los factores asociados con el desenlace. Por regresión logística múltiple se calculó el peso independiente de cada factor. Resultados: Se incluyeron 568 procedimientos, 59 % en el sexo femenino. La mediana de edad fue de 49 años; 65, 22 y 13 % de los casos tuvieron éxito, éxito intermedio y fracaso. El sexo femenino, urocultivo positivo, lito complejo e ICC severo se asociaron con fracaso. Conclusión: La probabilidad de éxito fue directamente proporcional al número de factores de riesgo.

Abstract Introduction: Success in percutaneous nephrolithotomy (PCNL) is defined as a stone-free status; however, major complications are highly common and have been reported as a secondary outcome. Objective: To propose a new definition of PCNL success that comprises a stone free rate without major complications and a risk scale to predict this outcome. Methods: Historical cohort of patients undergoing PCNL. The included variables were age, gender, urine culture, Charlson's comorbidity index (CCI) and complex stones. Success was defined as a stone free status with or without Clavien grade ≤ 2 complication; intermediate success: with stones, with or without Clavien grade ≤ 2 complication; and failure: with or without stones with Clavien grade ≤ 2 complication. Bivariate analysis was performed to identify which factors are associated with the outcome. The independent weight of each factor was calculated by multiple logistic regression analysis. Results: 568 procedures were included, 59% of which were in females. Median age was 49 years; 65%, 22% and 13% of cases were classified as success, intermediate success and failure, respectively. Female sex, positive urine culture, complex stones and severe CCI were associated with failure. Conclusions: The likelihood of success was directly proportional to the number of risk factors.

Comparative study of percutaneous nephrolithotomy performed in the traditional prone position and in three different supine positions

ABSTRACT Purpose: To compare the outcomes of percutaneous nephrolithotomy (PCNL) performed in the prone position (PRON) and in three variations of the supine position. Materials and Methods: We performed a retrospective analysis of patients that underwent PCNL at our institution from June 2011 to October 2016 in PRON and in three variations of the supine position: complete supine (COMPSUP), original Valdivia (VALD), and Galdakao - modified Valdivia (GALD). All patients had a complete pre - operative evaluation, including computed tomography (CT). Success was defined as the absence of residual fragments larger than 4 mm on the first post - operative day CT. Results: We analyzed 393 PCNLs: 100 in COMPSUP, 94 in VALD, 100 in GALD, and 99 in PRON. The overall success rate was 50.9% and was similar among groups (p = 0.428). There were no differences between groups in the number of punctures, stone - free rate, frequency of blood transfusions, drop in hemoglobin level, length of hospital stay, and severe complications (Clavien ≥ 3). COMPSUP had a significantly lower operative time than the other positions. COMPSUP had lower fluoroscopy time than VALD. Conclusion: Patient positioning in PCNL does not seem to impact the rates of success or severe complications. However, COMPSUP is associated with a shorter surgical time than the other positions.

Ureteroscopy and stone treatment in the elderly (≥70 years): prospective outcomes over 5- years with a review of literature

ABSTRACT Objective: To assess outcomes of ureteroscopy for treatment of stone disease in the elderly. Ureteroscopy (URS) is an increasingly popular treatment modality for urolithiasis and its applications are ever expanding with the development of newer technologies. Its feasibility and outcomes within the elderly population to our knowledge remain under-reported. Materials and Methods: We examined the patient demographics and surgical outcomes from our prospective database for patients ≥70 years who underwent URS for urolithiasis, in a 5-year period between March 2012 and December 2016. Results: A total of 110 consecutive patients underwent 121 procedures (1.1 procedure/patient) with a mean age of 77.2 years (range: 70-91 years). Stone location was in the kidney/ pelviureteric junction (PUJ) in 29%, ureter in 37% and in multiple locations in 34%. The initial and final stone free rate (SFR) was 88% and 97% respectively. While 73% were done as true day case procedures, 89% patients were discharged within 24 hours. Eleven patients (9%) underwent complications of which 10 were Clavien I/II including acute urinary retention, urinary tract infection, stent symptoms and pneumonia. One patient underwent Clavien IV complication where they needed intensive care unit admission for urosepsis but fully recovered and were discharged home subsequently. Conclusion: Ureteroscopy is a safe and effective method of managing urolithiasis in elderly patients. Although most patients are discharged within 24-hours, consideration needs to be made for patients where social circumstances can impact their discharge planning.

Differences in the percutaneous nephrolithotomy practice patterns among Latin American urologists with and without endourology training

ABSTRACT Purpose: Although the worldwide percutaneous nephrolithotomy (PCNL) practice pat- terns determined via a survey sent to members of the Endourological Society have been published, differences in PCNL practice patterns among Latin American urologists based on endourological or lithiasis training have not been published. To determine the PCNL practice patterns among Latin American urologists with and without training in endourology. Materials and Methods: The SurveyMonkey® web platform was used to develop a 27-item survey on PCNL for the treatment of renal stones, and the survey was sent via e- -mail and other electronic media to 2000 urologists from 15 Latin American countries. Endourology-trained (group 1) and nontrained urologists (group 2) were analyzed. The group results were compared using the chi-squared and Fisher's exact tests. SPSS version 20 for Windows was used for all analyses. Results: A total of 331 urologists responded to the survey (rate of 16.55%): 221 (66.7%) in group 1 and 110 (33.2%) in group 2). In groups 1 and 2, 91.9% and 63.2% performed PCNL, respectively: 85.1% and 58.5% used preoperative tomography, respectively; 12.7% and 4.7% used preoperative nephrolitometry nomograms, respectively: 45.2% and 32.1% used endoscopic combined intrarenal surgery, respectively: 68.3% and 38.7% used mul- tiple percutaneous tract realization, respectively: and 19.9% and 5.7% used minimally invasive PCNL, respectively (all p=0.0005). Conclusions: Statistically significant differences were observed in PCNL practice patterns of Latin American urologists with and without training in endourology. Specific training in endourology significantly influence the practice patterns of Latin American urologists.

Complicaciones anestésicas intraoperatorias y posoperatorias de la nefrolitotomía percutánea en pacientes con litiasis coraliforme / Intraoperative and postoperative anesthesia-related complications of percutaneous nephrolithotomy in patients with coraliform lithiasis

Introducción: En la actualidad la litiasis renal constituye entre el 20 y el 30 por ciento de las consultas de urología en el mundo. Objetivos: Identificar las complicaciones intra- y posoperatorias de la nefrolitotomía percutánea en pacientes con litiasis coraliforme. Métodos: Se realizó un estudio descriptivo en pacientes con diagnóstico de litiasis coraliforme ingresados para nefrolitotomía percutánea electiva en el Hospital Clínico Quirúrgico Hermanos Ameijeiras entre octubre 2010 y entre octubre 2015. Resultados: Se identificaron 32 pacientes con complicaciones intra y posoperatorias. Del sexo masculino fueron 68,7 por ciento. La media de la edad fue 47,59 ± 12,2 años. La clasificación ASA más frecuente fue ASA II en 56,2 por ciento. Todos los pacientes recibieron anestesia general. El valor medio de pérdidas hemáticas intraoperatorias fue de 650,00 ± 413,09 mL. La reposición total de volumen fue de 10, 107,80 ± 2, 659,25 mL. Se administró cloro sodio al 0,9 por ciento 7743,75 ± 2007,39 mL y concentrado de hematíes a 18,8 por ciento del total. Las complicaciones intraoperatorias se presentaron en 24 pacientes 75,0 por ciento. De ellas las más frecuentes fueron las metabólicas, cardiovasculares, respiratorias y renales. La hipotermia estuvo presente en la tercera parte de los enfermos. Las complicaciones posoperatorio se presentaron en 23 pacientes 71,9 por ciento. De ellas, cardiovasculares, respiratorias, renales y sépticas fueron las más frecuentes. Conclusiones: Las complicaciones fueron frecuentes y graves; sin embargo, se logró un porcentaje importante de pacientes egresados curados(AU)

Introduction: Renal lithiasis currently accounts for 20-30 percent of urology consultations worldwide. Objectives: To identify the intra- and postoperative complications of percutaneous nephrolithotomy in patients with staghorn lithiasis. Methods: A descriptive study was conducted in patients with a diagnosis of staghorn lithiasis and admitted for elective percutaneous nephrolithotomy Hermanos Ameijeiras Clinical-Surgical Hospital between October 2010 and October 2015. Results: We identified 32 patients with intra- and postoperative complications. The male sex was represented by the 68.7 percent. The mean age was 47.59±12.2 years. The most frequent ASA classification was ASA II, accounting for 56.2 percent. All patients received general anesthesia. The mean value of intraoperative hematic losses was 650.00±413.09 mL. Total volume replacement was 10, 107.80±2, 659.25 mL. Chloride sodium 0.9 percent was administered at doses 7743.75±2007.39 mL and packed red blood cells to 18.8 percent of the total. Intraoperative complications occurred in 24 patients, accounting for 75.0 percent. Of these, the most frequent were metabolic, cardiovascular, respiratory and renal. Hypothermia was present in one third of the patients. Postoperative complications occurred in 23 patients, accounting for 71.9 percent. Of these, cardiovascular, respiratory, renal and septic were the most frequent. Conclusions: The complications were frequent and serious. However, an important percentage number was achieved for cured discharge patients(AU)

Tratamiento de la litiasis renal con nefrolitotomía percutánea con láser en la población pediátrica: experiencia inicial / Treatment of kidney stones using percutaneous nephrolithotomy with laser in a pediatric population: an initial experience

Reportar nuestra experiencia inicial de nefrolitotomía percutánea (NLPC) con láser Holmium para el tratamiento de litiasis renal en la población pediátrica. Material y métodos: Estudio retrospectivo descriptivo de pacientes menores de 16 años con litiasis renal que fueron tratados con nefrolitotomía percutánea en el servicio de Urología del Hospital Garrahan en el período comprendido entre agosto de 2013 y marzo de 2015. Resultados: 19 procedimientos en 16 pacientes con un número de 17 unidades renales (UR) con una edad media de 7 años y un rango de 2 a 15 (Tabla 2). Los tipos de litiasis tratadas fueron: litiasis coraliforme en 6 pacientes (37,5%), coraliforme incompleto en 3 pacientes (18,7%), litiasis piélicas mayores de 2 cm en 4 pacientes (25%), litiasis piélicas menores de 2 cm en 2 pacientes (12,5%) y múltiples mayores de 2 cm en 1 paciente (6,25%). Se realizó acceso único en 15 pacientes, en sólo uno se configuró un segundo acceso y se reingresó o se realizó cirugía en dos tiempos en 3 pacientes (todos con litiasis coraliforme completa). La tasa de litiasis residual total fue del 21,1 %, todas ellas en litiasis coraliformes completas. Las complicaciones se observaron en 3 casos (18,7%) y fueron clasificadas como tipo III B en dos pacientes y del tipo I en uno. En los dos primeros se requirió conversión a vía abierta y en el último paciente solo se dejó colocada nefrostomía por 7 días. La internación promedio fue de 2,8 días con un rango de 1 a 15 días. El seguimiento medio fue de 7 meses con un rango de 4 a 13 meses. Conclusiones: La nefrolitotomía percutánea en pediatría es un método con baja morbilidad, que requiere una curva de aprendizaje prolongada y es determinante contar con todo el material necesario para "liberar" al riñón de litiasis urinaria (AU)

The aim of the study was to report our initial experience with percutaneous nephrolithotomy (PCNL) with holmium laser for the treatment of kidney stones in children. Material and methods: A descriptive retrospective analysis was conducted in patients younger than 16 years with kidney stones treated with PCNL at the department of urology of Garrahan Hospital between August 2013 and March 2015. Results: 19 procedures were performed in 16 patients with a number of 17 renal units (RU) and a mean age of 7 years, ranging from 2 to 15 years (Table 2). Types of kidney stones were: Staghorn kidney stones 6 patients (37.5%), partial staghorn kidney stones in 3 patients (18.7%), renal pelvis kidney stones larger than 2 cm in 4 patients (25%), renal pelvis kidney stones smaller than 2 cm in 2 patients (12.5%), and multiple kidney stones larger than 2 cm in 1 patient (6.25%). A single tract was performed in 15 patients, a second tract in only one, and re-entry or a two-step surgery was performed in 3 patients (all with complete staghorn kidney stones). The rate of residual stones was 21.1 %, all of them were complete staghorn stones. Complications occurred in 3 cases (18.7%) and were classified as type III B in two patients and type I in one. In the first two patients conversion to open surgery was necessary and in the remaining patient the nephrostomy was left in place for 7 days. Mean hospital stay was 2.8 days with a range of 1 to 15 days. Mean follow-up time was 7 months with a range of 4 to 13 months. Conclusions: In children PCNL is a procedure with low morbidity requiring a long learning curve. Availability of all the necessary materials is essential to be able to "release" the kidney from the stones (AU)