Introduction: Clamping of the renal artery during partial nephrectomy leads to renal ischemia and a deterioration of its function. An alternative to total ischemia is to isolate and clamp the segmental branch of the renal artery supplying the tumor.
Aim: To evaluate the efficiency of robot-assisted partial nephrectomy (RAPN) with selective renal ischemia.
Material and methods: A total of 42 patients with renal tumors of stage T1a (n=34) and T1b (n=8) undergoing RAPN were included in the study. There were 25 men (59.5%) and 17 women. The mean age was 56.0 +/- 7.5 years, the tumor size ranged from 2.5 to 6.8 cm. Patients with a solitary kidney, multiple tumors, and those who underwent partial nephrectomy with clamping of the renal artery were excluded from the study. CT angiography with 3D reconstruction were used to detect the segmental branches of the renal artery, that supply the tumor. To determine the complexity of renal tumors, the RENAL nephrometric scale was used. Complications were assessed according to the Clavien-Dindo classification. In addition, mean operative time and volume of blood loss, warm ischemia time, pre- and postoperative renal function, and oncological outcomes were analyzed. The RAPN was considered successful if it was performed with selective clamping of the artery.
Results: RAPN with selective ischemia was effective in 38 (90.5%) of 42 patients. In 4 (9.5%) cases with tumors of T1b stage and high RENAL scores (> 8), total ischemia was eventually used in order to control bleeding. According to CT angiography, these patients had more or equal 2 branches of renal artery, supplying the tumor. Mean operation time, volume of blood loss and warm ischemia time were 130.0+/-35 min, 185.0+/-80.0 ml and 14.0+/-3.2 min, respectively. In one case, there was an injury to the renal vein, which was sutured. Postoperative complications were observed in 5 (12.0%) patients. The glomerular filtration rate pre- and postoperatively was 76.5 and 72.0 ml/min/1.73 m2, and its decrease 1 month after RAPN was not significant (p>0.05).
Conclusion: Preoperative evaluation of renal arterial anatomy allows to detect the segmental branch that supplies the tumor. By its clamping, it is possible to perform efficient and safe robot-assisted partial nephrectomy without total ischemia.
Keywords: Da Vinci robot; partial nephrectomy; renal cell cancer; renal ischemia; robot-assisted partial nephrectomy; selective ischemia.