To access the kidney healing after laparoscopic partial nephrectomy without closuring of the collecting system in pigs.

Fourteen pigs underwent left partial laparoscopic nephrectomy, with removal of 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 vessels, tissue excision with cold scissor and monopolar energy hemostasis of only the parenchyma, leaving the collecting system opened, with no insertion of a double-J catheter. The animals were clinically evaluated during 14 days, and afterward were killed. Serum levels of urea and creatinine were assessed prior and at different moments after surgery. Macroscopic necropsy analysis, a retrograde ex vivo pyelogram and a histologic study of the operated renal poles were performed.

The animals did not show any postoperative clinical alterations. Serum levels of urea and creatinine showed a slight raising at the second postoperative day with gradual decreasing to preoperative levels. At necropsy, the abdominal cavity was normal, with normal quantity and aspect of peritoneal liquid. No signs of urine leakage were found. The operated renal pole was always involved by a perirrenal fibrosis with adherences to adjacent organs.

The pig kidney collecting system healed well without any kind of suture or internal drainage. Therefore, we concluded that the pig kidney is not an adequate model for research on which the collecting system healing is an important aspect to be considered.