Renal Function After Partial Nephrectomy: A Comparative Analysis of Warm, Cold, and No Ischemia Methods

Results from prior studies show contradictory evidence in determining whether utilization of renal ischemia during partial nephrectomies (PN) results in worse renal functional outcomes. Data assessing a large cohort of patients with no ischemia PN are lacking. The purpose of this study was to evaluate whether the use and type of renal ischemia during PN affects renal functional outcomes.

A retrospective review of 742 patients undergoing PN was assessed and split into 4 cohorts: no ischemia (n = 455), cold ischemia (n = 63), warm ischemia time (WIT) ≤ 30 minutes (n = 164), and WIT > 30 minutes (n = 60). Twelve-month relative glomerular filtration rate (GFR) changes and split function were assessed among the cohorts. Univariate and multivariable regression analyses were used to determine predictors of postoperative acute kidney injury and long-term renal functional outcomes.

No difference in the mean relative decrease in GFR was noted among the 4 cohorts at either the 3-month (8.7% ± 25.5%, P = .1) or 12-month (7.5% ± 19.0%, P = .2) period. On multivariable analysis, age (coefficient [coef]: 0.3, P < .001), estimated blood loss (coef: 0.2 per 100 mL, P = .02), baseline GFR (coef: 2 per 10 units, P < .001), number of tumors resected (coef: 0.4, P = .02), and postoperative acute kidney injury (coef: 8.3, P < .001) were predictive of a higher percentage decrease in 12-month GFR while male sex (coef: -6.3, P = .001) was inversely related. The type of ischemia or length of WIT was not associated with 12-month GFR change.

In patients undergoing PN, the use of and type of ischemia affects short-term but not long-term renal functional outcomes. Facility with multiple ischemia techniques may be useful in the management of patients requiring complex PN.