Early unclamping technique during robot-assisted laparoscopic partial nephrectomy can minimise warm ischaemia without increasing morbidity

Abstract

Objective: To compare perioperative outcomes of early unclamping (EUC) vs standard unclamping (SUC) during robot-assisted partial nephrectomy (RAPN), as early unclamping of the renal pedicle has been reported to decrease warm ischaemia time (WIT) during laparoscopic PN.

Patients and methods: A retrospective multi-institutional study was conducted at eight French academic centres between 2009 and 2013. Patients who underwent RAPN for a renal mass were included in the study. Patients without vascular clamping or for whom the decision to perform a radical nephrectomy was taken before unclamping were excluded. Perioperative outcomes were compared using the chi-squared and Fisher's exact tests for discrete variables and the Mann-Whitney test for continuous variables. Predictors of WIT and estimated blood loss (EBL) were assessed using multiple linear regression analysis.

Results: In all, there were 430 patients: 222 in the EUC group and 208 in the SUC group. Tumours were larger (35.8 vs 32.3 mm, P = 0.02) and more complex (R.E.N.A.L. nephrometry score 6.9 vs 6.1, P < 0.001) in the EUC group but surgeons were more experienced (>50 procedures 12.2% vs 1.4%, P < 0.001). The mean WIT was shorter (16.7 vs 22.3 min, P < 0.001) and EBL was higher (369.5 vs 240 mL, P = 0.001) in the EUC group with no significant difference in complications or transfusion rates. The results remained the same when analysing subgroups of complex renal tumours (R.E.N.A.L. nephrometry score ≥7) or RAPN performed by less experienced surgeons (<20 procedures). In multivariable analysis, EUC was predictive of decreased WIT (β -0.34; P < 0.001) but was not associated with EBL (β -0.09, P = 0.16).

Conclusions: EUC can reduce WIT during RAPN without increasing morbidity even for complex renal tumours or when being performed by less experienced surgeons.

Keywords: complications; early unclamping; partial nephrectomy; robotic; warm ischemia time.