Evaluation of functional outcomes after laparoscopic partial nephrectomy using renal scintigraphy: clamped vs clampless technique

Abstract

ObjectivesTo examine differences in postoperative renal functional outcomes when comparing clampless with conventional laparoscopic partial nephrectomy (LPN) by using renal scintigraphy, and to identify the predictors of poorer postoperative renal functional outcomes after clampless LPN. Patients and Methods Between September 2010 and September 2012, 87 patients with renal masses suitable for LPN were prospectively enrolled in the study. From September 2010 to September 2011, LPN with renal artery clamping was performed and from September 2011 to September 2012 clampless LPN (no clamping of renal artery) was performed. Patients who underwent clampless LPN were unselected and consecutive, and the procedure was performed at the end of surgeon's learning curve. Patients were divided into two groups according to warm ischaemia time (WIT): group A, conventional LPN and group B, clampless‐LPN (WIT = 0 min). Demographic and peri‐operative data were collected and analysed and functional outcomes were evaluated using biochemical markers and renal scintigraphy at baseline and at 3 months after surgery. The percentage loss of renal function, evaluated according to renal scintigraphy, was calculated. Chi‐squared and Student's t‐tests were carried out and regression analysis was performed. Results Group A was found to be similar to group B in all variables measured except for WIT and blood loss (P < 0.001). The percentage reduction in renal scintigraphy values was not significantly different between the groups (reductions of 5% in group A and 6% in group B for split renal function [SRF] and 12% in group A and 17% in group B for estimated renal plasmatic flow [ERPF]; P = 0.587 and P = 0.083, respectively). Multivariate analysis in group B showed that the lower the baseline values of SRF and ERPF, the poorer the postoperative functional outcome of the treated kidney. Conclusions In our experience, even clampless LPN was not found to be functionally harmless. The patients who benefitted most from a clampless approach were those with the poorest baseline renal function.

Method Used for Tumor Bed Closure (Suture vs. Sealant), Ischemia Time and Duration of Surgery are Independent Predictors of Post-Nephron Sparing Surgery Acute Kidney Injury

“…Similar findings to ours were reported by Mir et al [25] and Aertsen et al [26]. Others however, reported a direct relationship, that is, large and more complex tumors predicted postoperative AKI [27,28].…”

Impact of the off-clamp endoscopic robot-assisted simple enucleation (ERASE) of clinical T1 renal tumors on the postoperative renal function: Results from a matched-pair comparison

“…However, after the sixth postoperative month, the global RF was not significantly influenced by the hilum management (as long as WIT was <30 min). Similarly, Porpiglia et al reported that the split RF assessed using renal scan was not significantly different in patients undergoing laparoscopic PN with off-clamp vs. modest (<25 min) ischemia [9]. Conversely, Trehan in a meta-analysis of six observational comparative studies reported a significantly longterm lower fall in eGFR in patients who underwent off-clamp PN compared to those who underwent on-clamp PN [27].…”

“…However, the use of off-clamp procedures is increasingly adopted to maximize the functional outcome after conservative surgery as prolonged ischemia time has been associated with a significantly higher RF impairment [8]. Nevertheless, a definitive functional benefit of offclamp PN has not been proved yet [3,9,10]. Beyond a possible protective effect on postoperative RF, off-clamp PN could be associated with a higher complication and positive surgical margin (SM) rate due to a higher bleeding and a subsequent suboptimal vision [11].…”

Perioperative and renal functional outcomes of laparoscopic partial nephrectomy (LPN) for renal tumours of high surgical complexity: a single-institute comparison between clampless and clamped procedures

“…Current evidence suggests that the amount of residual functional parenchyma after PN represents a significant surgical factor that impacts on post-operative renal function [9,20] and that warm ischaemia time (WIT) is a wellknown predictor of post-operative eGFR [9]. Given these findings, it would be advisable to perform a clampless partial nephrectomy removing the danger risk of sacrificing healthy parenchyma.…”

“…Thompson et al [8] demonstrated that "every minute counts" when the renal hilum is clamped and that warm ischaemia time (WIT) is a well-known predictor of the post-operative estimated glomerular filtration rate (eGFR). Given this restriction, it is advisable to perform a clampless PN whenever feasible, particularly in patients with poor baseline renal function [9]. The aim of the present study was to assess the feasibility and safety of LPN for renal tumours of high surgical complexity in our single-institutional experience, comparing perioperative and functional data between clampless and clamped procedures.…”