Kidney/Aorta Ratio for Renal Morphometric Determination in Swine Subjected to Acute Kidney Injury Using an Optimized Surgical Model

This research aims to establish an experimental surgical model for access to the renal pedicle and kidney and to determine renal length measurement via the kidney/aorta ratio (K/AO) using ultrasound. Fifteen swine underwent ventral median celiotomy with a supraumbilical transverse incision to access the right and left renal pedicles and induce renal ischemia-reperfusion injury (IRR). The kidneys were evaluated using ultrasonography to standardize renal length, aortic diameter, and the K/AO. Assessment was performed at 2 time points: 1 h before and 24 h after the surgery to induce IRR. Blood and urine samples were collected to assess renal function. Histologic evaluation of kidney fragments was also conducted. The proposed abdominal cavity access method proved to be highly efficient for exposing the right and left renal pedicles and inducing IRR. Serum levels of urea, creatinine, calcium, and phosphorus, as well as levels of the urinary protein/urinary creatinine ratio and urinary GGT, did not show significant differences. Acute kidney injury was confirmed through histopathology. The mean lengths of the right and left kidneys were 82.63 and 87.64 mm, respectively. The values of the right and left K/AO were 9.81 and 10.38, respectively. There was no statistically significant difference in the K/AO ratio before and after IRR. The proposed surgical model allowed surgical intervention on the renal pedicles without intra- or postoperative complications. Furthermore, the K/AO could be measured through ultrasonography, establishing a reference for healthy animals.