Prolonged Cold Ischemia Time for Laparoscopic Partial Nephrectomy with a New Cooling Material: Freka-Gelice—A Comparison of Four Cooling Methods

Abstract Background and Purpose: It is well known that hypothermia protects renal tissue from ischemic damage. So far, no standardized cooling method for laparoscopic surgery has been established. The traditionally used cooling method during open partial nephrectomy (OPN) is crushed ice applied around the kidney; for laparoscopic use, transarterial and transureteral perfusion cooling are described. We compared these three cooling methods with Freka-Gelice (FG), a new gel-like cooling material, and present our initial preliminary results in an ex-vivo porcine model. Materials and Methods: To prove cooling effectiveness, FG was compared with superficial crushed ice (NaCl-ice), with transureteral perfusion (TUP), and with transarterial perfusion (TAP) cooling in ex-vivo porcine kidneys. The temperature decrease over 120 minutes and practical application were evaluated. Results: No significant difference was found for the mean value distribution at different time points for NaCl-ice and FG (P = 0.18). TUP and...