Feasibility of Omitting Cortical Renorrhaphy During Robot-Assisted Partial Nephrectomy

Abstract

Introduction: Use of robot-assisted partial nephrectomy is increasing rapidly for the treatment of patients with small renal masses. The use of cortical renorrhaphy has traditionally been used in partial nephrectomy to prevent urine leaks and postoperative bleeding; however, the efficacy of this technique in preserving renal function has never been questioned. In this video, we demonstrate the different techniques of robot-assisted partial nephrectomy (i.e., omission of cortical renorrhaphy vs. a standard two-layer renorrhaphy), assess the safety of this base-only layer technique, and measure preliminary functional outcomes. Materials and Methods: Fifteen robot-assisted partial nephrectomies were performed with a running, base-layer suture for the collecting system and vessel hemostasis, but without cortical renorrhaphy. The nonrenorrhaphy group was retrospectively matched 1:2 by R.E.N.A.L. nephrometry score to a running, sliding-clip cortical renorrhaphy group. Intraoperative blood loss, postoperative urine leaks, postoperative hemorrhage, and functional outcomes were evaluated. Predictors of percentage volume loss were evaluated using multivariable regression. Results: No differences were seen between renorrhaphy and nonrenorrhaphy in sex (p = 0.53), age (p = 0.14), body mass index (p = 0.08), Charlson score (p = 0.44), tumor diameter (p = 0.55), nephrometry score (p = 0.77), preoperative glomerular filtration rate (GFR, p = 0.63), or the amount of resected healthy kidney margin (p = 0.21). Warm ischemia time was less for the nonrenorrhaphy group (p < 0.002). One pseudoaneurysm necessitating embolization (1/30 = 3%) was seen in the renorrhaphy group compared with none in the nonrenorrhaphy group. No urine leaks occurred in either group. The median percentage GFR loss was 8.8% for renorrhaphy and 4.4% for nonrenorrhaphy (p = 0.14) at a median follow-up of 4.1 months. The median percentage volume loss was 17 cm3 for renorrhaphy and 9 cm3 for nonrenorrhaphy (p = 0.003). In a multivariable model, both cortical renorrhaphy (p = 0.004) and tumor diameter (p = 0.004) were predictors of percentage volume loss. Conclusion: Omission of cortical renorrhaphy appears feasible with no urine leaks or bleeding complications observed. The percentage renal volume loss was improved by omission of cortical renorrhaphy. Reconstruction technique is important to control for when studying renal function after partial nephrectomy. No competing financial interests exist. Runtime of video: 7 mins 56 secs