Primary intracerebral hemorrhage (ICH), or spontaneous nontraumatic bleeding into the brain parenchyma, constitutes 10% to 15% of strokes in the United States, affecting approximately 65,000 people each year. Furthermore, ICH causes substantial disability in survivors, with only 20% of patients expected to be functionally independent at 6 months. ICH also places a large financial burden on families and the US health care system, with the average hospitalization cost of nonsurvivors estimated to be $16,466 and the hospitalization cost of survivors to be $28,360 (with an additional post-discharge cost of $16,035 during the first year)
Acute vessel rupture, potentially due to small arteries with aneurysmal dilatation or dissection, then causes injury by several mechanisms. First, there is mass effect from the hematoma itself. Next, there is activation of the coagulation cascade, chemotaxis of leukocytes, expression of adhesion molecules, release of inflammatory cytokines, and disruption of the blood-brain barrier. Finally, continued bleeding, or hematoma expansion, occurs in many patients. Proposed explanations include continued bleeding from the primary source, secondary bleeding at the periphery of the hemorrhage , and potentiation of hemorrhage by acute hypertension or a locally coagulopathic environment |