The Impact of Arterial Clamping Technique in Robot-Assisted Partial Nephrectomy on Renal Function and Surgical Outcomes: Six-Year Experience at Siriraj Hospital, Thailand

Abstract

Introduction: Robot-assisted partial nephrectomy (RAPN) with different arterial clamping techniques has increasingly been performed to avoid ischemic injury to nephron. However, postoperative renal function remains controversial. We determine the impact of each renal arterial clamping on surgical and renal outcomes after RAPN. Materials and Methods: Patients who underwent RAPN at Siriraj Hospital from 2010 to 2016 were retrospectively reviewed and stratified into 3 cohorts: main-clamp (MAC), selective-clamp, and off-clamp. Results: Main, selective, and off-clamping were performed in 27, 38, and 12, respectively. Median tumor size and Radius, Exophytic or endophytic, Nearness to collecting system or sinus, Anterior or posterior, and Location relative to polar lines (RENAL) score were 3 cm and 7, respectively. Longer operative time was observed in MAC (p = 0.002) although estimated blood loss, transfusion rate, and complication were comparable. Warm ischemia time was not different between cohorts. However, number of patients with prolonged ischemia time in MAC were greater (p ≤ 0.01). All margins were negative. Median postoperative and latest glomerular filtration rate reduction were 3.8 and 5.3 mL/min/1.73 m², respectively without significant difference between cohorts. On multivariable analysis, hypertension independently associated with reduced renal function preserved (p = 0.03). Median follow-up was 18 months. Conclusions: Our study is the first to report surgical and renal functional outcomes after RAPN in Southeast-Asian population. Based on our experience, clamping techniques does not impact on renal functions and complication rate was low even in small-volume center.

Off-clamp partial nephrectomy has a positive impact on short- and long-term renal function: a systematic review and meta-analysis

“…Off-clamp partial nephrectomy (off-PN) has been a common strategy to avoid ischemia in small renal tumor. Although a consensus has been reached on off-PN risking more blood loss, the impact of the two methods on the change of postoperative short- and long-term renal function remains unclear [ 1 , 9 ]. Therefore, we systematically searched and analyzed the clinical studies comparing off-PN with on-PN for small renal masses published until January 2018 to assess the methods’ impact on short- and long-term renal function.…”

How Much Zero-Ischemia Do We Really Need in the Real-Life Scenario?

“…Taweemonkongsap et al [1] are not the first to demonstrate the same phenomenon [6]. Additionally, they did not observe any cardiovascular event during the 6-year period.…”

“…Taweemonkongsap et al [1] present a retrospective long-term study focussing on one of the most debated issues of (robot-assisted) partial nephrectomy: What is the impact of the clamping technique? Based on 6 years of relevant experience, they present 77 cases of which 27 patients were treated by clamping of the renal artery, 38 patients were treated by clamping only the branches (i.e., selective clamping), and 12 patients were treated without clamping of the renal vessels (i.e., off-clamp).…”

Selective clamping during robot‐assisted partial nephrectomy in patients with a solitary kidney: is it safe and does it help?

“…Although some studies report that SAC does cause a smaller reduction in eGFR in the short term [8‐11], others indicate that change in renal function after 6 months is comparable to that caused by MAC [10]. There is even evidence that SAC does not improve renal function even in the short term [12,13] and may actually be associated with longer operating time and greater estimated blood loss [14]. Overall, the utility of SAC remains uncertain.…”