¿Cómo afecta la técnica de punción al riesgo de sangrado intraoperatorio durante la nefrolitotomía percutánea? Ensayo aleatorizado prospectivo / How does puncture modality affect the risk of intraoperative bleeding during percutaneous nephrolithotomy? A prospective randomized trial

Introducción y objetivos: Evaluar los posibles efectos de dos técnicas diferentes de punción renal (guiada por ecografía [GE] o guiada por fluoroscopia [GF]) sobre el riesgo de hemorragia intraoperatoria durante la nefrolitotomía percutánea (NLPC).Material y métodosUn total de 130 pacientes con puntuaciones de la escala de Guy de 1-2 fueron asignados prospectivamente a los grupos de punción GE y punción GF mediante aleatorización simple. Se excluyeron del estudio los pacientes que sufrieron rotura pielocalicial durante la cirugía y los que necesitaron múltiples accesos. Aparte de los pasos relacionados con la punción, todos los demás pasos del procedimiento de NLPC fueron realizados con técnicas similares por un único cirujano. Se compararon las características de los pacientes, los datos quirúrgicos y los resultados postoperatorios.ResultadosUn total de 10 pacientes fueron excluidos del estudio debido a una complicación intraoperatoria tras la punción. Los datos demográficos de los pacientes y las características de los cálculos fueron similares entre los dos grupos (p>0,05). La media del descenso de hemoglobina fue significativamente mayor en el grupo GF (1,7g/dl) en comparación con el grupo GE (1,3g/dl) (p<0,01). La duración media de la exposición a la radiación fue significativamente mayor en el grupo GF (p<0,001). El tiempo quirúrgico total, el número de intentos para una punción exitosa, la duración de la estancia hospitalaria y la tasa libre de cálculos fueron similares entre los grupos (p>0,05). Asimismo, las demás complicaciones clasificadas según la escala modificada de Clavien-Dindo fueron similares entre los grupos (p>0,05).ConclusiónLa punción guiada por ecografía (GE) proporciona niveles significativamente menores de descenso de hemoglobina y tiempo de exposición a la radiación en comparación con el procedimiento guiado por fluoroscopia (GF). (AU)

Introduction and objectives: To evaluate the possible effects of two different renal puncture techniques (ultrasound-assisted [US-assisted], fluoroscopic-guided [FG]) on the intraoperative hemorrhage risk during percutaneous nephrolithotomy (PCNL).Material and methodsA total of 130 patients with Guy stone scores of 1-2 were prospectively allocated to US-assisted and FG puncture groups by simple randomization. Patients with intraoperative pelvicalyceal rupture and the ones requiring multiple accesses were excluded from the study. Apart from the puncture steps, all other steps of the PCNL procedure were performed with similar techniques by a single surgeon. Patient characteristics, operative data, and postoperative outcomes were compared.ResultsA total of 10 patients were excluded from the study due to intraoperative complications after puncture. Patient demographics and stone characteristics were similar between the two groups (P>.05). Mean hemoglobin drop was meaningfully greater in the FG group (1.7g/dL) when compared with US-assisted group (1.3g/dL) (P<.01). The mean duration of radiation exposure was significantly higher for the FG (P<.001). Total operative time, number of attempts for a successful puncture, length of hospital stay, and stone free rates were similar between the groups (P>.05). In addition, the remaining complications classified according to the modified Clavien-Dindo grading system were similar between groups (P>.05).ConclusionUS-assisted puncture provides significantly decreased level of hemoglobin drop and radiation exposure time when compared with FG. (AU)

How does puncture modality affect the risk of intraoperative bleeding during percutaneous nephrolithotomy? A prospective randomized trial.

INTRODUCTION AND OBJECTIVES: To evaluate the possible effects of two different renal puncture techniques (ultrasound-assisted [US-assisted], fluoroscopic-guided [FG]) on the intraoperative hemorrhage risk during percutaneous nephrolithotomy (PCNL). MATERIAL AND METHODS: A total of 130 patients with Guy stone scores of 1-2 were prospectively allocated to US-assisted and FG puncture groups by simple randomization. Patients with intraoperative pelvicalyceal rupture and the ones requiring multiple accesses were excluded from the study. Apart from the puncture steps, all other steps of the PCNL procedure were performed with similar techniques by a single surgeon. Patient characteristics, operative data, and postoperative outcomes were compared. RESULTS: A total of 10 patients were excluded from the study due to intraoperative complications after puncture. Patient demographics and stone characteristics were similar between the two groups (p > 0.05). Mean hemoglobin drop was meaningfully greater in the FG group (1.7 g/dL) when compared with US-assisted group (1.3 g/dL) (p < 0.01). The mean duration of radiation exposure was significantly higher for the FG (p < 0.001). Total operative time, number of attempts for a successful puncture, length of hospital stay, and stone free rates were similar between the groups (p > 0.05). In addition, the remaining complications classified according to the modified Clavien-Dindo grading system were similar between groups (p > 0.05). CONCLUSION: US-assisted puncture provides significantly decreased level of hemoglobin drop and radiation exposure time when compared with FG.

Minimally Invasive Approach to Ureteral Stricture in Transplant Kidney by Periodic Retrograde Ureteral Stent Placement and Exchange.

PURPOSE: The aim of the study was to evaluate the effectiveness of minimally invasive treatment of ureteral strictures and describe the technique that we used for retrograde placement of ureteral stent in transplant kidneys. MATERIAL AND METHODS: We reviewed the medical cards of all transplant kidney patients with persistent ureteral strictures who were managed with periodical ureteral stent placement and balloon dilatation between 2008 and 2016. Different maneuvers that were used to overcome the difficulties for retrograde ureteral stent placement and exchange were discussed. Clinical characteristics and treatment outcomes of the study cohort were analyzed. RESULTS: Between 2008 and 2016, a total of 1026 transplantations were performed in our clinic, and ureteral stricture was found in 13 patients (1.26%). Of the 13 patients, 8 were treated with periodic ureteral stent insertion and balloon dilatation. Ureteral stent insertion or stent exchange was performed in 52 transplant renal units. The overall success rate of retrograde ureteral stent insertion at the first attempt was 75% and stent exchange success rate was 100%. Renal function remained stable in all patients during a median follow-up of 41 months (range, 13-60 months). No other local or systemic complication was encountered and no stent encrustation was noted. CONCLUSIONS: Endoscopic management of ureteral stricture by periodical retrograde ureteral stent replacement and balloon dilatation is safe, effective, and highly successful in transplant patients who are not eligible for open reconstructive surgery.

Flexible Ureterorenoscopy and Laser Lithotripsy for the Treatment of Allograft Kidney Lithiasis.

OBJECTIVE: To evaluate the safety and effectiveness of flexible ureterorenoscopy (F-URS) and laser lithotripsy for the treatment of allograft kidney lithiasis. PATIENTS AND METHODS: In a retrospective analysis of 897 consecutive renal transplantations that were performed at our center between February 2008 and December 2014, 6 patients were found to have allograft lithiasis. F-URS and laser lithotripsy were performed 6 times on 5 patients (twice for 1 patient who had stone recurrence after 6 months). Percutaneous nephrolithotomy was used for the remaining patient. Patient demographics and stone characteristics (age, sex, stone size, stone analysis, location, history of shockwave lithotripsy) and perioperative measures (duration of operation, fluoroscopic imaging, success and complication rates) were reviewed. In addition, the technical difficulties of standard F-URS procedures in transplanted kidneys were reviewed and some facilitative techniques were defined to increase the success rate. RESULTS: A total of 5 patients underwent 6 F-URS procedures and laser lithotripsy operations for renal graft lithiasis. The mean stone size was 9.2 mm (7.5-11 mm). The mean operation and fluoroscopy times were calculated as 55 minutes (40-70 minutes) and 57.5 seconds (40-80 seconds), respectively. Treatment was successful in all patients and no severe complications or mortality occurred. One patient experienced transient hematuria and recovered within 36 hours. CONCLUSION: F-URS is a safe, effective, and minimally invasive treatment modality for small- and medium-sized stones in allograft kidney lithiasis.