title: Brain ischemia in patients with intracranial hemorrhage: pathophysiological reasoning for aggressive diagnostic management.
abstract: Patients with intracranial hemorrhage have to be managed aggressively to avoid or minimize secondary brain damage due to ischemia, which contributes to high morbidity and mortality. The risk of brain ischemia, however, is not the same in every patient. The risk of complications associated with an aggressive prophylactic therapy in patients with a low risk of brain ischemia can outweigh the benefits of therapy. Accurate and timely identification of patients at highest risk is a diagnostic challenge. Despite the availability of many diagnostic tools, stroke is common in this population, mostly because the pathogenesis of stroke is frequently multifactorial whereas diagnosticians tend to focus on one or two risk factors. The pathophysiological mechanisms of brain ischemia in patients with intracranial hemorrhage are not yet fully elucidated and there are several important areas of ongoing research. Therefore, this review describes physiological and pathophysiological aspects associated with the development of brain ischemia such as the mechanism of oxygen and carbon dioxide effects on the cerebrovascular system, neurovascular coupling and respiratory and cardiovascular factors influencing cerebral hemodynamics. Consequently, we review investigations of cerebral blood flow disturbances relevant to various hemodynamic states associated with high intracranial pressure, cerebral embolism, and cerebral vasospasm along with current treatment options.
authors.affiliation: Department of Diagnostic Radiology of the University of Maryland, Division of Clinical Research; Baltimore, Maryland, USA - jkrejza@umm.edu - jkrejza@me.com.
authors.forename: Daniel
authors.initials: D
authors.lastname: Naranjo
authors.forename: Michal
authors.initials: M
authors.lastname: Arkuszewski
authors.forename: Wojciech
authors.initials: W
authors.lastname: Rudzinski
authors.forename: Elias R
authors.initials: ER
authors.lastname: Melhem
authors.forename: Jaroslaw
authors.initials: J
authors.lastname: Krejza
mesh_terms: D002545:Brain Ischemia / Q000209:etiology* / Q000503:physiopathology; D002560:Cerebrovascular Circulation / Q000502:physiology*; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D020300:Intracranial Hemorrhages / Q000150:complications*; D012307:Risk Factors
keywords: brain ischemia; cerebral blood flow; cerebral emboli; cerebral hemodynamics; cerebral ischemia; cerebral perfusion review; cerebral vasospasm; subarachnoid hemorrhage