Theoretical evaluation of a simple cooling pad for inducing hypothermia in the spinal cord following traumatic injury.

The Pennes bioheat equation and finite element method (FEM) are used to solve for the temperature distributions in the spinal cord and cerebrospinal fluid (CSF) during 30 min of cooling for spinal cord injury (SCI) patients. The average CSF and spinal cord temperatures are reduced by 3.48 and 2.72 degrees C, respectively. The 100-mm wide pad provides the desired cooling and uses the least amount of material. The presence of zero-average CSF oscillation under normal conditions decreases the cooling extent in the spinal cord due to the introduction of warm CSF surrounding the spinal cord. The temperature decrease in the spinal cord is more than doubled when the temperature at the back of the torso is lowered from 20 to 0 degrees C. Spinal cord ischemia, often observed after traumatic spinal cord injury, promotes cooling penetration. The proposed technique can reduce the spinal cord temperature by 2 degrees C within 30 min and may be a feasible treatment for traumatic SCI.