Cicatrização renal após nefrectomia parcial laparoscópica sem fechamento do sistema coletor em porcos

Abstract

Although some studies have described similarities and differences between human and pig kidney anatomy, little is known regarding renal healing in this animal model. The knowledge of pig kidney healing is especially important in surgical procedures which incise the renal parenchyma and collecting system, such as partial nephrectomy. The aim of this study is to access kidney healing in pigs after laparoscopic partial nephrectomy without closuring of the collecting system. Fourteen male pigs with mean weight of 30 kg were submitted to left partial laparoscopic nephrectomy, removing 25% of the kidney length at caudal pole (n = 7) or at cranial pole (n = 7). Briefly, the surgical technique involved a transperitoneal laparoscopic access, en bloc vascular clamping of renal artery and vein, tissue excision with cold scissor and monopolar energy parenchyma hemostasis, leaving the collecting system opened. The animals were clinically evaluated during fourteen days, and afterwards were killed. Serum levels of creatinine and urea were assessed prior and at different moments after surgery. Necropsy findings, retrograde ex vivo pyelogram and histological aspects of operated renal poles are also described. Serum creatinine and urea showed a slight initial increase with a gradual return to preoperative levels during the evaluated period. At necropsy, no signs of urine leakage were found and kidneys were covered by a fibrous tissue with adherences to adjacent organs. Also, in the retrograde pyelograms obtained, we did not find contrast medium leakage by operated poles. Histological findings showed great deposition of type I collagen over operated renal pole, sealing it completely. The pig kidney is not an adequate experimental model for research and training of surgery on which collecting system healing is an important aspect to be considered.