Aneurysmal subarachnoid hemorrhage is a serious condition with a high morbidity and mortality rate despite advances in neurocritical care. Intraparenchymal monitors providing continuous bedside physiological data have been introduced into the care of the neurocritically ill and are the focus of clinical research. We review the available technology for bedside brain monitoring and the knowledge that has been gathered and its clinical utility by organizing it into 3 main areas: detecting vasospasm early, establishing end points to resuscitation in the management of cerebral vasospasm, and developing insights into the pathophysiology of the disease. Finally, we discuss its implications for the field and future directions.
