Kidney warming during transplantation

Abstract The objective of the present study was to describe kidney temperature variations during transplantation and to identify the factors responsible for kidney warming. Kidney temperature was recorded steadily during transplantation. Kidney weight, body mass index (BMI), second warm ischemia time (t), and kidney temperature at the time of being placed in the recipient were analyzed so that we could evaluate their influence on kidney temperature and on kidney warming during transplantation. Kidney temperature at the time of removal from the container was 1.6 °C and 6.3°C when the kidney was placed in the recipient. Kidney temperature in the recipient depended on kidney temperature after serum washing (P<0.0001), but was independent of kidney preparation time (P=0.94). Then, kidney temperature (T) increased according to the logarithmic curve given in the following equation: T=7.2 In(t)–0.6. Kidney temperature at the end of anastomosis was 26.7 °C. Kidney warming speed was 0.48 °/min and was dependent on the length of time of vascular anastomosis (P<0.0001). Kidney weight decreased the kidney warming speed (P=0.02). In conclusion, kidney warming increases slowly during ex vivo preparation. Kidney temperature stays below the damaging ischemic temperature of 18°C. Because of its major impact on kidney warming, it is desirable that vascular anastomosis time be reduced, and, consequently, ex vivo kidney preparation needs to be meticulous.