Effect of renal ischemia in laparoscopic acute versus chronic solitary kidney model

OBJECTIVES The effects of renal warm ischemia (WI) in an acute versus a chronic single kidney model have not been investigated. Previously, we reported full recovery of renal function after 90 minutes of WI in a single-kidney porcine model. Here, we sought to assess the effects of WI on renal function in an acute versus chronic solitary kidney in the porcine model. METHODS A total of 32 pigs weighing 60 to 80 lb were randomized into four groups. Group 1 (acute model) underwent nephrectomy followed by 90-minute immediate WI clamping of the contralateral renal hilum. Group 2 (control for group 1) underwent nephrectomy followed by contralateral sham renal pedicle surgery. Group 3 (chronic model) underwent nephrectomy followed 12 days later by 90-minute WI clamping of the contralateral renal hilum. Group 4 (control for group 3) underwent nephrectomy followed 12 days later by contralateral sham renal pedicle surgery. Serum creatinine and the glomerular filtration rate were assessed preoperatively and on postoperative days 1, 3, 8, and 15. All procedures were performed laparoscopically. RESULTS The acute model showed a significantly greater increase in serum creatinine and lower glomerular filtration rate nadir compared with the chronic model on postoperative days 1, 3, and 8. By postoperative day 15, the serum creatinine and glomerular filtration rate were comparable between the acute and chronic groups after WI. CONCLUSIONS Renal dysfunction in the acute model was significantly more profound during the initial 8 days after WI compared with that in the chronic model. These results validate our acute single kidney porcine model as a practical and cost-effective model when performing renal ischemia research.