Monitoring brain tissue oxymetry: will it change management of critically ill neurologic patients?

Based on the assumption that brain ischemia and hypoxia are central causes of brain damage, the maintenance of an adequate tissue oxygenation is a primary objective in the field of neurocritical care. Thus, monitoring brain tissue oxymetry, allowing the possibility to discriminate between normal and critically impaired tissue oxygenation, is recognized as an essential part of the management of the neurological critically ill patient. The clinical usefulness of this neuromonitoring tool in the area of neurosciences (traumatic brain injury, aneurysm surgery, arteriovenous malformation resection, brain tumors) is discussed. Monitoring brain tissue oxymetry not only allows the detection of impending cerebral ischemia, thus providing the clinician with essential information for the management and correction of harmful intracerebral events, but it also helps in understanding the pathophysiology of neuro-injury. It can also be used as a "surrogate end point" to evaluate putative therapies, targeting therapy towards improved cerebral oxygenation. As brain tissue oxygenation correlates closely with outcome, several outcome categories have been differentiated, aiding in predicting prognosis after injury. The rationale for monitoring brain tissue oxygenation is to provide essential information about oxygen supply and utilization in this specific tissue bed, thus reducing secondary brain damage and improving neurological outcome.