The effect of renal artery-only or renal artery-vein clamping during partial nephrectomy on short and long-term functional results: Is clamping technique important?

Purpose To evaluate the effect of artery-only (AO) and artery-vein (AV) clamping during partial nephrectomy (PN) on short- and long-term renal function outcome. Methods Medical records of 154 patients in the AO group and 192 patients in the AV group who underwent open and minimally invasive (laparoscopic/robotic) PN between January 2011 and January 2018 were retrospectively assessed. Preoperative patient and tumor-specific characteristics in addition to perioperative factors and renal function outcomes were compared. The change in the estimated glomerular filtration rate (eGFR) from postoperative 1-3 days, 12 and 24 months after surgery was calculated. Acute kidney injury (AKI) was defined a as a > 25% reduction in eGFR. Results There were no statistically significant differences between the clamping techniques in terms of postoperative 1-3 days, 12 and 24 months eGFR change percentage and risk of progression to chronic kidney disease (CKD). No significant difference in short- and long-term renal functions was found between the minimally invasive or open AO and AV clamping subgroups at any time point. In multivariate analysis, the R.E.N.A.L score (AO group p = 0.026, AV group p < 0.001) and preoperative eGFR (AO group p < 0.001, AV group p = 0.010) were strong predictors of the acute kidney injury in both groups. Older age (AO group p = 0.045, AV group p = 0.010) and preoperative eGFR (AO group p = 0.008, AV group p = 0.002) were significantly associated with CKD progression at 2-year follow-up in both groups. Conclusion AV clamping does not adversely affect postoperative renal function compared to AO clamping. Preoperative patient- and tumor-related factors are more important for renal function regardless of the clamping technique.