Brain swelling in traumatic brain injury

The generation of cerebral edema after traumatic brain injury is a complex heterogeneous process and it may differ based on the non-modifiable nature of primary injury, patient characteristics, and additional clinical insults as hypoxia, hypotension, hyperthermia, and seizure. The blood-brain barrier has a pivotal role in the genesis of brain edema: when cerebral edema results from insults other than closed head trauma, changes in brain tissue specific gravity or water content are associated with increased permeability of the blood-brain barrier. Cerebrovascular permeability to serum proteins may remain intact in purely cytotoxic edema, whereas increased entry of water into brain parenchyma is primarily related to osmotic gradients and interference with cellular osmoregulation. Highly active chemical factors and derangements of the cerebral microcirculation lead to a damage in the blood-brain barrier developing a vasogenic cerebral edema. It mainly affects the capillary endothelium that constitutes this barrier disrupting the tight junctions between the cells. This chapter is intended to serve as a foundation and a reference from which researchers and clinicians might have practical understanding of cerebral edema. In addition, we will classify clinical characteristics of brain swelling on the base of type of traumatic brain injury and Glasgow Coma Scale.