Z-shaped running suture for outer layer renorrhaphy during robot-assisted partial nephrectomy

BACKGROUND: The aim of this study was to describe a novel outer layer renorrhaphy strategy during robot-assisted partial nephrectomy. METHODS: This technique is presented in key steps. Renorrhaphy is performed with a double layer technique. The novel strategy of outer layer renorrhaphy is to approach the parenchymal margins in a zigzag-shaped manner with a 2-0 Vicryl running suture. Each pass begins immediately adjacent to the exit site. The needle is passed through the defect and the exiting suture is secured with a Hem-o-lok clip. At each exit site, the suture is secured with a Hem-o-lok clip. A second Hem-o-lok clip is placed at the loose ends, to tighten the suture in the clip locking mechanism. Patients submitted to robot-assisted partial nephrectomy at a single institution between January 2017 and January 2022 were included in the analysis. Descriptive statistics of baseline characteristics and surgical, pathological, and oncological outcomes were analyzed. RESULTS: One hundred fifty-nine consecutive patients were recorded; 103 (64.8%) of them presented with a cT1a renal mass. Median (interquartile range IQR) total operative time was 146 (120-182) minutes. There was no conversion to open surgery, while 5 (3.1%) patients were converted to radical nephrectomy. We reported an overall low rate of postoperative complications. There were 5 documented perirenal hematomas and 6 cases of urinary leakage (2 pT2a, 2 pT1b, 2 pT1a renal cell carcinoma). CONCLUSIONS: Z-shaped technique is a feasible and safe alternative for renorrhaphy of the outer layer, in experienced hands. Future comparative studies are needed to confirm our results.