When kidney experience ischemia for 15 minutes at room temperature, it will get a temporary dysfunction. The ischemia duration within 30 minutes can not cause obvious renal damage. Along with the prolonged ischemia of kidney, the range and degree of renal damage will become more and more serious, leading to kidney tissue necrosis and kidney function complete loss eventually.
There are two ways to store donor kidney, one is to reduce the metabolism as far as possible, strengthen the tolerance of the kidney tissue; another is artificial supply the necessary nutrients to keep the energy of donor kidney.
Cryopreservation is the common method for donor kidney preservation, the temperature is generally above freezing poin. The main cryopreservation methods include pute cooling method and hypothermal perfusion. The function of hypothermal is to protect the metabolism of donor kidney, in order to prolong the vitality of the kidney. The metabolism function can be reduced with the decreasing of system temperature, which will fade away when the temperature decreasing to less than 5 degree C.
Pute cooling method means that pouring cold perfusate into arterial system fast with the help of gravity, reduce the kidney temperature to less than 10 degree C, then steep the kidney into hypothermic preserving fluid at 1~4 degree C until the transplant need.
Hypothermal perfusion is using specially-made pulse or impulse type of machine pouring perfusate into donor kidney with low flow pressure, maintain the temperature of perfusate and donor kidney at 6~10 degree C, in order to remove waste products and supply the basic nutrition for the metabolism in low temperature.
Read more please refer to "Pros and Cons of Kidney Transplant"
