Functional recovery after partial nephrectomy: next generation analysis

Objectives To provide a more rigorous assessment of factors affecting functional recovery after partial nephrectomy (PN) using novel tools that allow for analysis of more patients and improved accuracy for assessment of parenchymal volume loss, thereby revealing the potential impact of secondary factors such as ischaemia. Patients and Methods Of 1140 patients managed with PN (2012–2014), 670 (59%) had imaging and serum creatinine levels measured before and after PN necessary for inclusion. Recovery from ischaemia was defined as the ipsilateral glomerular filtration rate (GFR) saved normalised by parenchymal volume saved. Acute kidney injury was assessed through Spectrum Score, which quantifies the degree of acute ipsilateral renal dysfunction due to exposure to ischaemia that would otherwise be masked by the contralateral kidney. Multivariable regression was used to identify predictors of Spectrum Score and Recovery from Ischaemia. Results In all, 409/189/72 patients had warm/cold/zero ischaemia, respectively, with median (interquartile range [IQR]) ischaemia times for cold and warm ischaemia of 30 (25–42) and 22 (18–28) min, respectively. The median (IQR) global preoperative GFR and new baseline GFR (NBGFR) were 78 (63–92) and 69 (54–81) mL/min/1.73 m2, respectively. The median (IQR) ipsilateral preoperative GFR and NBGFR were 40 (33–47) and 31 (24–38) mL/min/1.73 m2, respectively. Functional recovery correlated strongly with parenchymal volume preserved (r = 0.83, P