Abstract
Primary intracerebral hemorrhage (ICH) results from spontaneous rupture of an intracranial vessel and is associated with high rates of early mortality and long-term morbidity. No surgical or medical intervention has been demonstrated to improve outcome. Acute blood pressure elevation is seen in the majority of patients with ICH and is correlated with poor outcome. Potential, but unproven, mechanisms for this association include facilitation of hematoma expansion as well as perihematomal edema growth. Conversely, the perihematomal region has also been hypothesized to have ischemic properties. Therefore, management of blood pressure in the acute phase lends itself to two competing rationales and the optimal target blood pressure remains unknown. A number of parenchymal and blood-flow imaging techniques have been utilized to improve our understanding of blood flow and metabolism in acute ICH. These studies generally indicate that ischemia is not a major pathophysiological mechanism of secondary injury in ICH. Ultimately, randomized, controlled trials, which are underway, will be required to definitively determine the safety and efficacy of acute blood pressure reduction. It appears most likely that earlier and more aggressive treatment of acute blood pressure will be recommended in the future.