Method Used for Tumor Bed Closure (Suture vs. Sealant), Ischemia Time and Duration of Surgery are Independent Predictors of Post-Nephron Sparing Surgery Acute Kidney Injury

Introduction: The aim of our study was to examine the influence of tumor complexity and operative variables on the degree and rate of post-nephron sparing surgery (NSS) acute kidney injury (AKI). Methods: We retrospectively reviewed the records of 477 patients who underwent NSS for enhancing renal masses in our institution. AKI was determined using the latest definition by AKIN and RIFLE criteria. Serum creatinine was assessed daily starting from day 1 post-surgery and until discharge (usually on postoperative day 3). Estimated glomerular filtration was determined using the Modification of Diet in Renal Disease equation. Results: Overall, 191 patients (40%) developed postoperative AKI, and most of them (88%) were grade 1. Multivariate analysis revealed that the most significant and independent variables associated with AKI were operation time (p = 0.02), ischemia time (p = 0.02), and the use of tissue adhesive for tumor bed closure (p = 0.02). Other important factors (by univariate analysis) were the need for blood transfusion (p = 0.003) and estimated blood loss (p = 0.007). Conclusions: Operative time, ischemia, and tumor bed closure method are independent predictors of post-NSS AKI. Efforts should be made to limit prolonged ischemia and to reduce viable parenchymal loss. Further studies concerning the functional impact of AKI in these patients will be required.