Acute Ischemic Neurological Deficits (AINDs)
SAH due to rupture of intracranial aneurysms is characterized by the suddenness of the appearance of symptoms. The most frequent symptom is headache which may be accompanied by nausea and vomiting. Often, the patient rapidly lapses into coma of variable severity and duration. Although an exact figure has not been known, it has been estimated that a considerable percentage of SAH patients die immediately after ictus which accounts for 2% of all sudden deaths (Freytag 1966). In the remaining patients, some may recover consciousness or be freed from headache in hours or days, and some may present more persisting major neurological deficits. In SAH, it is recognized as a common pattern that the symptoms or the neurological deficits are the most severe immediately after its onset (AINDs), which tend to gradually improve later. Then, in about half of the patients, secondary deteriorations in the neurological status take place (DINDs). These characteristics in the evolution of symptoms and signs are telling us that the major brain damage is inflicted at the time or close to the time of aneurysmal rupture, and another harmful event occurs later. In this chapter, the nature of brain damages pertaining to AINDs and pathomechanisms involved in their occurrence will be delineated.
KeywordsCerebral Blood Flow Intracranial Hypertension Cerebral Perfusion Pressure Global Ischemia Reactive Hyperemia
Unable to display preview. Download preview PDF.