Techniques to Ameliorate the Impact of Second Warm Ischemic Time on Kidney Transplantation Outcomes

Anastomosing the renal artery and vein in transplant recipients without a cooling mechanism exposes the kidney to temperatures exceeding the metabolic threshold (15°C to 18°C), at which the protective effects of renal hypothermia are lost. This anastomotic time, or second warm ischemic time, can be deleterious to graft outcomes, especially if it is prolonged. Techniques to ameliorate organ warming prior to reperfusion have been designed, and range from simpler surface cooling techniques, to organ immersion in bags of ice slush, and the application of 'jackets' that incorporate their own internal cooling mechanism. The efficacy of these methods with respect to the minimization of kidney temperature prior to reperfusion and subsequent effects on graft outcomes are discussed using clinical and experimental data, in the setting of open, laparoscopic, and robotic kidney transplantation.