Early clamp release during laparoscopic partial nephrectomy: Implications for preservation of renal function.

Abstract

Intraoperative warm ischemic time (WIT), associated with hilar clamping during partial nephrectomy (PN), is an established modifiable risk factor for renal dysfunction. We assessed early clamp release (ECR) as a strategy to reduce WIT and assess its impact on renal function and bleeding. We retrospectively assessed patients who underwent minimally invasive PN by a single surgeon at our centre since December 2011. Comparing the standard technique to an ECR modification, WIT, complications, change in estimated glomerular filtration rate (eGFR), and change in differential function as demonstrated by MAG-3 nuclear renography were assessed. Followup blood work and renograms were performed at 6-12 weeks postoperatively and compared to baseline in 70 patients (35 ECR: 35 control). The ECR and control groups were similar in age, sex, and tumour size, with only patient weight being higher in the ECR group (91.6 vs. 81.6 kg; p<0.05). WIT was significantly lower in ECR group compared to control (18.8 vs. 31.5 minutes; p<0.05). Although there was no significant difference in change from baseline eGFR in the early postoperative period (Day 3) or in followup (6-12 weeks), the control group had a significantly greater loss of ipsilateral renal function from baseline compared to the ECR group (9 vs. 4% change; p<0.05). Blood loss and complication rate were similar between groups. The ECR technique offers a safe, reproducible alternative that reduces WIT during laparoscopic PN. ECR demonstrates a reduction in overall ipsilateral renal dysfunction, without increasing complication or intraoperative bleeding risk.