This chapter explains the mechanisms leading to neuronal cell death and the most important neuroprotective strategies. Cerebral ischaemia and/or hypoxia may occur as a consequence of shock, respiratory failure, vascular stenosis or occlusion, vasospasm, neurotrauma or cardiac arrest. Ischaemic or traumatic challenges affect both inadequate delivery of oxygen and glucose, and impairment of mitochondrial function, leading to inadequate production of ATP. Two different types of cell death may occur following brain injury: necrosis and apoptosis. New therapeutic targets could be designed to obtain a correct modulation of the immune system and to reduce cerebral damage after brain injury. The proposed mechanisms of anaesthetic protection include reduction of cerebral metabolism and intracranial pressure (ICP), and suppression of seizures and sympathetic discharge. Hypoxia and ischaemia are recognized as important driving forces of erythropoietin expression in the brain, suggesting that erythropoietin is part of a self-regulating physiological protection mechanism to prevent neuronal injury.

In childhood-onset multiple sclerosis (MS), the cerebrospinal fluid (CSF) profile is not fundamentally different from the adult-onset MS. Magnetic resonance imaging (MRI) is the best imaging technique to detect lesions suggestive of MS in children. The initial clinical course in most patients with childhood-onset MS is relapsing-remitting. In the UCSF cohort, the initial MS event was moderate or severe in 86% of children compared with 56% of adult-onset MS. In the UCSF pediatric-onset cohort, complete recovery was seen in 66%, which was similar to adults seen at the same center, questioning whether children have less irreversible neuronal injury during their first event or/and have a better ability to repair. MS is likely the result of a complex interplay between genes and environment. Potential prognostics factors associated with the assignment of disability milestones have been examined in several cohort studies from adult centers and one cohort from child neurology centers.