Thermal properties of porcine and human biological systems

For applications of bioheat transfer such as thermal therapies and cryopreservation, the temperature excursions experienced by a biomaterial can be directly correlated to the injuries that may occur in the system. Thermal modeling is an important tool in order to predict this temperature history as it is not always possible to experimentally measure the temperature and cooling/heating rates experienced by the biomaterials. These models make use of temperaturedependent thermal properties in order to accurately predict the thermal histories experienced by the systems. This review chapter focuses on listing literature data of human and porcine systems for thermal conductivity and specific heat capacity in the cryogenic, subzero, and suprazero temperature ranges. At subzero and cryogenic temperatures, thermal properties are affected by phase change (water to ice) and vitrification or glass formation in the presence of cryoprotectants, whereas water loss and protein denaturation are important factors at suprazero temperatures. Finally, a modeling case study is provided demonstrating the use and necessity of temperature-dependent properties in order to make accurate predictions for thermal history.