Correlation of the RENAL nephrometry score with warm ischemia time after robotic partial nephrectomy

The RENAL nephrometry score (RNS) was developed to quantify complexity of renal tumors in a reproducible manner. We aim to determine whether individual categories of the RNS have different impact on the warm ischemia time (WIT) for patients undergoing robotic partial nephrectomy (RPN). In a retrospective analysis of a prospectively maintained database, we identified 251 consecutive patients who underwent RPN between January 2007 and June 2010. RNS was determined in 187 with available imaging. Univariable analysis and multivariable linear regression analysis were performed to identify which factors were more significantly associated with WIT. Overall RNS was of low (4–6), moderate (7–9), and high complexity (10–12) in 84 (45 %), 80 (43 %), and 23 (12 %) patients, respectively. There was no association between gender (p = 0.6), BMI (p = 0.3), or anterior/posterior location (A) (p = 0.8), and WIT. On univariable analysis, longer WIT was associated with size (R) >4 cm (p