Presentation Authors: Junya Furukawa*, Nobuyuki Hinata, Yuzo Nakano, Masato Fujisawa, Kobe, Japan
Introduction: The selective arterial clamping (SAC) technique was developed as an alternative to total arterial clamping (TAC) in an effort to improve renal functional outcomes after partial nephrectomy. The aim of this study was to evaluate whether the selective SAC technique during robot-assisted partial nephrectomy (RAPN) provides any renal functional benefit over TAC in patients with >1 year of follow-up.
Methods: Our study cohort comprised 208 patients without impaired renal function who underwent SAC (n=55) or TAC (n=153) during RAPN performed by a single surgeon at Kobe University Hospital during the period of 2011-2016. To minimize the selection bias between the two clamp methods, both RENAL nephrometry score and warm ischemia time (WIT) were adjusted by 1:1 propensity score matching.
Results: After propensity score matching, 55 patients were included in each clamping technique group. SAC and TAC RPN patients were compared with no significant differences in age, gender, surgical approach (trans- or retroperitoneal), tumor size, baseline estimated glomerular filtration rate (eGFR), American Society of Anesthesiologists (ASA) physical status or Karnofsky performance status. The mean WIT was 19.1 min in the SAC group and 19.6 min in the TAC group. The mean nephrometry score was 6.8 in both groups. The SAC group had a greater mean blood loss volume (58.5 vs 24.5 ml; p=0.048) than the TAC group. No significant differences were found between the groups regarding the positive surgical margin (0%), overall complication rate (7.2 vs 5.4%; p=0.779) or trifecta achievement (85.5 vs 90.1%; p=0.556). Regarding postoperative renal function, the SAC group had significantly less deterioration at 1 week after surgery (percentage reduction in eGFR -9.7 vs -16.7%; p=0.002), but this outcome was not observed after 1 month (9.4 vs 11.1%; p=0.356) to over 1 year (10.8 vs 12.1%; p=0.441). Of note, SAC was more beneficial for patients with a high CKD stage (>G3) to reduce the decrease in eGFR after surgery (n=18, each group).
Conclusions: Our data suggested that the SAC technique results in superior short-term renal functional outcomes compared with TAC; however, after 1 postoperative month, there were no significant differences regarding the renal functional outcome when the mean WIT was less than 20 minutes in our series. Furthermore, the SAC technique may be beneficial for patients with a high CKD stage in order to preserve renal function.