The cerebral perfusion pressure (CPP) is the driving force for transcapillary movement of blood, the cerebral blood flow (CBF) and depends on cardiac output, mean arterial blood pressure (MAP), peripheral vascular resistance and intracranial pressure (ICP). As the CBF is equal to the quotient of CPP and vascular resistance, it can be increased by auto-regulatory vasodilation . CBF is constant over a wide range of MAP values as cerebral vasodilation or vasoconstriction counter any changes in MAP; this is the so-called Bayliss effect. In ischemic brain, this mechanism is not functional and CBF is directly dependent on MAP. Cerebral ischemia itself is more often focal than global and is most frequently caused by an acute occlusion of intracranial arteries due to an embolism from an extracranial vessel or from the heart.
KeywordsCerebral Blood Flow Cerebral Perfusion Pressure Mean Arterial Blood Pressure Vessel Occlusion Ischemic Penumbra
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