Tehran University Medical Journal

Background: Brain hypothermia by reducing the temperature of the cerebrospinal fluid is done by a cooling pad in the thoracic region and protect brain from the ischemic injuries. Along with the spinal cord, the brain is an essential partner in the central nervous system, and similarly, it is surrounded and protected from the bony skull and from shock by cerebrospinal fluid. The brain analyzes information that is both internal and external to the body, transforms the information into sensations, and stores them as memories. So in this study we investigated the brain hypothermia by finite element modeling.

Methods: To investigate this phenomenon, in this study a numerical model of the head with respect to the structure of brain tissue and its contribution to heat transfer is presented in the fluid lab of the Amirkabir University of Tehran in January of 2016. In this model, Pennes's bioheat equation and finite element analysis has been used to predict temperature distribution in the brain tissue. The model geometry is designed in two state without considering the ventricles of the brain that are involved in the production of cerebrospinal fluid and with considering cerebrospinal fluid. So, in the second case, the cerebrospinal flow is considered as a heat transfer factor.

Results: We concluded that with cooling about 5 °C, in the first model without considering the ventricles, the gray matter temperature is reduced by about 4 °C and there is no change in white matter temperature. In the second model temperature distribution became more asymmetric. The temperature reduced about 3 °C in the corners. However, the temperature reduction at the edge of brain tissue and near cerebrospinal fluid were about 0.5 °C.