Early unclamping might reduce the risk of renal artery pseudoaneurysm after robot-assisted laparoscopic partial nephrectomy.

Kondo, Tsunenori; Takagi, Toshio; Morita, Satoru; Omae, Kenji; Hashimoto, Yasunobu; Kobayashi, Hirohito; Iizuka, Junpei; Yoshida, Kazuhiko; Fukuda, Norihiro; Tanabe, Kazunari

OBJECTIVES To determine the influence of the early unclamping technique on the risk of renal artery pseudoaneurysm during robot-assisted laparoscopic partial nephrectomy. METHODS From January 2013 to October 2014, 96 patients underwent robot-assisted laparoscopic partial nephrectomy for renal masses at Tokyo Women's Medical University Hospital, Tokyo, Japan. Computed tomography angiography was carried out 3-4 days after surgery. Early in the series, renal hilum was left unclamped and renorrhaphy was subsequently carried out (conventional unclamping technique). An early unclamping technique has been used since November 2013. RESULTS A total of 61 patients underwent robot-assisted laparoscopic partial nephrectomy with early unclamping, and 35 patients underwent robot-assisted laparoscopic partial nephrectomy with conventional unclamping. Ischemia time was significantly shorter in the early unclamping group (16.5 vs. 23.1 min; P < 0.01). The early unclamping group showed a significantly lower incidence of asymptomatic renal artery pseudoaneurysm relative to the conventional unclamping group (11.4% vs. 28.6%; P = 0.03). Multivariate analysis showed that the early unclamping technique was a significant independent factor in reducing the risk of renal artery pseudoaneurysm (hazard ratio 0.27; P = 0.01). CONCLUSIONS The present findings suggest that an early unclamping technique might reduce ischemic time and risk of renal artery pseudoaneurysm. The absence of arterial bleeding before renorrhaphy is likely to be a key step in preventing renal artery pseudoaneurysm during robot-assisted laparoscopic partial nephrectomy.