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  • Online publication date: July 2019

Chapter 14 - Subarachnoid Hemorrhage in the Neurocritical Care Unit


Subarachnoid hemorrhage (SAH) is an acute cerebrovascular event with profound effects on the central nervous system and several other organs, and is defined by bleeding into the subarachnoid space between the arachnoid layer and pia mater. SAH occurs with an incidence of 2–22.5 per 100,000 [1,2]. The highest reported incidences of aneurysmal SAH (aSAH) come from Japan and Finland and occur at a rate of 16–22.5 per 100,000 per year. In the United States, SAH occurs at approximately 6 per 100,000, or a total of 18,000 events per year. The incidence of aSAH peaks in the 55–60-year-old age group. Additionally, subarachnoid hemorrhage is a consequence of traumatic brain injury in 12–53%, which corresponds to approximately 240,000 persons per year in the United States.

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