Finite Element Modelling of heat exchange in the stroke-affected brain during therapeutic hypothermia

Abstract

Hypothermia is a promising neuroprotectant for the treatment of ischaemic stroke. Current trials of hypothermia rely on cooled blood to reduce the temperature of ischaemic brain tissue. However, since blood flow to the ischaemic brain tissue is compromised, there is likely to be spatial variation in the rate and level of cooling accomplished by cooled blood in this tissue. Finite Element Modelling was used to investigate variation the effectiveness of tissue cooling as a result of spatial variations in cerebral blood flow and cerebral metabolic rate. These factors were found to affect the absolute level of tissue cooling achievable, but not the rate of cooling. This study suggests that pharmaceutical reduction of cerebral metabolic rate may improve the effectiveness of current cooling techniques by minimising spatial variation in brain temperature as a result of impaired blood flow, thereby potentially improving patient outcome.