Diogo Benchimol de Souza1, Waldemar S Costa2, Jose A Damasceno-Ferreira3, Amary Nascimento Júnior4, Fabio O Ascoli5, Marco A Pereira-Sampaio6, Francisco J Sampaio2. 1. Urogenital Research Unit, Department of Anatomy, State University of Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil. Electronic address: diogobenchimol@gmail.com. 2. Urogenital Research Unit, Department of Anatomy, State University of Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil. 3. Urogenital Research Unit, Department of Anatomy, State University of Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil; Department of Veterinary Clinical Pathology, Fluminense Federal University, Niterói, Rio de Janeiro, Brazil. 4. Department of Veterinary Clinical Pathology, Fluminense Federal University, Niterói, Rio de Janeiro, Brazil. 5. Department of Physiology and Pharmacology, Fluminense Federal University, Niterói, Rio de Janeiro, Brazil. 6. Urogenital Research Unit, Department of Anatomy, State University of Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil; Department of Morphology, Fluminense Federal University, Niterói, Rio de Janeiro, Brazil.
Abstract
BACKGROUND: The pig has been considered the best model for renal surgery. However, recent research has demonstrated that the kidney of pigs heals differently from that of humans. The objective of this study was to evaluate sheep as an alternative animal model for studying collecting system healing after laparoscopic partial nephrectomy. MATERIALS AND METHODS: The caudal pole of the left kidney was removed from eight female adult domestic sheep using laparoscopic partial nephrectomy. Monopolar energy was used for hemostasis only in the parenchyma, avoiding coagulation near the collecting system, which was left opened. After 14 d, all animals were euthanized, and their left kidney was removed. Serum levels of urea and creatinine were assessed preoperatively and postoperatively (on days 2, 6, 10, and 14), and peritoneal fluid samples were collected during necropsy for urea and creatinine evaluation. An ex vivo retrograde pyelogram was performed, and a retrograde injection of methylene blue ink was administered to evaluate urinary leakage. Samples from the operated pole were analyzed using histologic methods. RESULTS: During necropsy, an urinoma surrounding the operated kidney was observed in one animal. Peritoneal fluid levels of urea and creatinine were elevated. Retrograde pyelograms exhibited contrast-medium extravasation through the operated pole in all kidneys. The opened collecting system was also confirmed by methylene blue ink injection. The operated pole was covered by collagenous tissue and adhered to adjacent organs. CONCLUSIONS: Sheep should be considered as an adequate experimental model for research on collecting system healing after partial nephrectomy.
BACKGROUND: The pig has been considered the best model for renal surgery. However, recent research has demonstrated that the kidney of pigs heals differently from that of humans. The objective of this study was to evaluate sheep as an alternative animal model for studying collecting system healing after laparoscopic partial nephrectomy. MATERIALS AND METHODS: The caudal pole of the left kidney was removed from eight female adult domestic sheep using laparoscopic partial nephrectomy. Monopolar energy was used for hemostasis only in the parenchyma, avoiding coagulation near the collecting system, which was left opened. After 14 d, all animals were euthanized, and their left kidney was removed. Serum levels of urea and creatinine were assessed preoperatively and postoperatively (on days 2, 6, 10, and 14), and peritoneal fluid samples were collected during necropsy for urea and creatinine evaluation. An ex vivo retrograde pyelogram was performed, and a retrograde injection of methylene blue ink was administered to evaluate urinary leakage. Samples from the operated pole were analyzed using histologic methods. RESULTS: During necropsy, an urinoma surrounding the operated kidney was observed in one animal. Peritoneal fluid levels of urea and creatinine were elevated. Retrograde pyelograms exhibited contrast-medium extravasation through the operated pole in all kidneys. The opened collecting system was also confirmed by methylene blue ink injection. The operated pole was covered by collagenous tissue and adhered to adjacent organs. CONCLUSIONS:Sheep should be considered as an adequate experimental model for research on collecting system healing after partial nephrectomy.
Authors: Daniel H Zidde; Francisco J B Sampaio; Paulo de Souza-Junior; Diogo B de Souza; Marco A Pereira-Sampaio Journal: Int Braz J Urol Date: 2020 Nov-Dec Impact factor: 1.541