Although brain injury from nontraumatic subarachnoid and intracerebral hemorrhage represents a small percentage of vascular injury to the brain, a not insignificant amount of resources and attention is directed each year to the study of these entities. Investigators from traditional disciplines (neurology and neurosurgery) are joined in increasing numbers by neuroradiologists, neurointensivists, cerebral physiologists, and molecular scientists. The end result is an ever-evolving therapeutic regiment increasingly based on scientific study. At the bedside, this translates into a more well-defined understanding of the issues facing the clinician caring for these patients. In the current review, the authors update our understanding of these two disease processes given the most recently published studies involving humans. With regard to subarachnoid hemorrhage, new information on epidemiology and risk of hemorrhage are discussed as well as the latest clinical studies of nonsurgical ablation of aneurysms and invasive treatment of cerebral vasospasm. Intracerebral hemorrhage presents unique difficulties to the clinician, with uncertain roles for medical and surgical therapy. Although raised intracranial pressure is a common feature of most hemorrhages, the two brain injuries are different in degree and mechanism of parenchymal injury. Secondary neuronal injury either because of delayed vascular ischemia (subarachnoid hemorrhage) or direct mass effect with ensuing edema (intracranial hematoma) offer subsequent challenges sometimes long after the initial injury. In each of these areas, small strides are being made in knowledge of pathophysiology and insight into new potential treatments on a yearly basis. Innovative new therapies and reexamination of old paradigms are occurring simultaneously. Outcome studies will likely show that a combination of new diagnostic and therapeutic technology coupled with a combined effort by treating physicians from several areas within the neurosciences will make the difference in the long run.
ASJC Scopus subject areas
- Critical Care and Intensive Care Medicine