NCBI Bookshelf. A service of the National Library of Medicine, National Institutes of Health.

Cipolla MJ. The Cerebral Circulation. San Rafael (CA): Morgan & Claypool Life Sciences; 2009.

Cover of The Cerebral Circulation

The Cerebral Circulation.

Show details

Chapter 1Introduction

As an organ, the brain comprises only about 2% of body weight yet it receives 15–20% of total cardiac output, making the brain one of the most highly perfused organs in the body. The high metabolic needs of the brain, relying heavily on oxidative metabolism, necessitate not only a high fraction of cardiac output but also relatively constant blood flow. The brain is also unique in that it is enclosed by the skull, a bony rigid structure that does not allow for expansion of either tissue or extracellular fluid without significant deleterious effects. Swelling of the brain due to vasogenic edema can increase intracranial pressure (ICP) and cause severe neurologic complications and even death. Because of the importance to maintain ICP within normal ranges and also to provide an appropriate ionic milieu for neuronal function, water and solute transport from the blood into the brain parenchyma is controlled in very special ways. The cerebral circulation is also unique in that the large arteries account for a greater proportion of vascular resistance in the brain than in many other vascular beds. This unusually prominent role of large arteries in vascular resistance likely helps to provide constant blood flow to neuronal tissue and protect the cerebral microcirculation during fluctuations in arterial pressure. In this chapter, structural and functional aspects of the cerebral circulation will be reviewed, including many of its unique properties. Given the large amount of subject matter, however, not all aspects of this unique circulation will be covered in detail.

Copyright © 2010 by Morgan & Claypool Life Sciences.
Bookshelf ID: NBK53083

Views

Recent Activity

Your browsing activity is empty.

Activity recording is turned off.

Turn recording back on

See more...