Application of Hypothermic Perfusion via a Renal Artery Balloon Catheter During Robot-assisted Partial Nephrectomy and Effect on Renal Function

To assess the feasibility, safety, and effect of hypothermic perfusion on postoperative renal function employing a renal artery balloon catheter inserted via robot-assisted partial nephrectomy (h-RAPN) to treat renal tumors.Forty-three patients with renal tumors were studied between March 2013 and August 2017. Renal artery balloon catheters were placed under angiographic guidance, and the balloon was fully inflated to occlude the renal artery during surgery. After establishing venous outflow, a robot-assisted partial nephrectomy was performed following perfusion with sodium lactate Ringer's solution at 4°C through the balloon catheter. Renal dynamic imaging was used to assess renal function, with calculation units consisting of glomerular filtration rate per unit volume of the kidney (GFR-UV).Six patients were converted to radical nephrectomy intraoperatively, and the remaining 37 patients successfully underwent the h-RAPN procedure. Two patients had incomplete occlusion of the renal artery and received supplementary arterial clamp occlusion intraoperatively. One patient's balloon catheter slipped out of position preoperatively, and the patient was returned to the interventional radiology suite for balloon reinsertion, after which the patient underwent surgery successfully. No patients had severe complications. The average cold ischemia time was 39.5 ± 9.7 min (range, 22-123 min), the average temperature of the affected kidney during surgery was 19.3 ± 3.5°C (17.2-26.7°C), the average postoperative GFR-UV of the affected kidney was 0.42 ± 0.09 ml/min/ml (0.21-1.24 ml/min), and the average postoperative GFR-UV of the healthy kidney was 0.30 ± 0.04 ml/min/ml (P > 0.05). Multiple regression analysis indicated that cold ischemia time was an independent risk factor affecting the postoperative GFR of the affected kidney.The advantages of h-RAPN include a clear surgical field enabling precise resection. When hypothermic perfusion via a renal artery balloon catheter is performed in conjunction with h-RAPN, the surgical time can be lengthened without increasing impairment of the affected kidney function, making this a safe and effective method of treating kidney tumors.