Absence of asymptomatic unruptured renal artery pseudoaneurysm on contrast-enhanced computed tomography after robot-assisted partial nephrectomy without parenchymal renorrhaphy

Abstract Objective To assess the incidence of asymptomatic unruptured renal artery pseudoaneurysm (RAP) on contrast-enhanced computed tomography (CE-CT) after robot-assisted partial nephrectomy (RAPN) without parenchymal renorrhaphy. Methods From May 2016 to December 2017, 78 patients underwent RAPN for renal tumors. Inner suture was performed in the opened collecting system or renal sinus, whereas parenchymal renorrhaphy was not. For hemostasis, the soft coagulation system was used, and absorbable hemostats were placed on the resection bed. CE-CT was carried out within 7 days after surgery. Data on these patients were prospectively collected. A single radiologist determined the diagnosis of RAP. Results Median (range) data were as follows: patient: Patient age, 65 (19-82) years; radiographic tumor size, 30 (12–95) mm; operating time, 166 (102–294) min; warm ischemic time, 16 (7–67) min; and blood loss, 15 (0–4450) ml. One patient (1.6%) required a perioperative blood transfusion. No patient required conversion to open surgery or nephrectomy. CE-CT was carried out at median 6 (3–7) days after surgery. CT showed no RAP development in all 61 patients. Urinary leakage was not observed. One patient had acute cholecystitis, a postoperative complication classified as Clavien-Dindo grade higher than 3, which was treated with cholecystectomy. Positive surgical margin was identified in four patients (6.6%). Conclusion RAPN using soft coagulation and absorbable hemostats without renorrhaphy appears to be feasible and safe. Our technique could eliminate the risk of RAP.