How does anesthesia affect various levels of experimental traumatic brain injury?

The use of anesthetics is a well-known treatment for severely injured patients. In the present study we tested the pathophysiology of several levels of injury damage in a rat model and also tested the effect of Equithesin on brain vitality in these models. Traumatic Brain Injury (TBI) was induced using the fluid percussion injury model in four levels: mild, moderate and two levels of severe TBI. Brain real-time evaluation was performed by the multiparametric monitoring assembly (MPA) which enable cerebral blood flow (CBF) monitoring by laser Doppler flowmetry, mitochondrial NADH (Nicotinamide adenine dinucleotide) monitoring by the fluorometric technique, ionic homehostasis using special mini-electrodes, intracranial pressure (ICP) by the ICP camino device and needle electrodes for ECoG (Electrocorticogram) recording. Our results showed high correlation between the level of impact and the extent of changes in the physiological properties of the injury as indicated by the changes in all parameters monitored using the MPA device. Moreover, Equithesin improved CBF, ionic extracellular level and mitochondrial redox state following mild and moderate TBI while in severe TBI, Equithesin did not improve the metabolic state of the cerebral cortex, although it decreased the mortality rate from 66% to 20%, and following extra-severe TBI level, Equithesin did not improve survival rate. In conclusion it seems that Equithesin's protective effect exists under mild to moderate levels of injury and not in case of severe injuries.