Affordable Access

Mammalian cardiovascular morphology and the maintenance of cerebral function at high Gz.

Authors
Type
Published Article
Journal
Aviation Space and Environmental Medicine
0095-6562
Publisher
Aerospace Medical Association
Publication Date
Volume
65
Issue
7
Pages
666–669
Identifiers
PMID: 7945137
Source
Medline

Abstract

The persistence of consciousness at low cerebral perfusion pressures during exposure to high sustained G force in a head-to-foot direction (+Gz), is the rule. Concomitant changes in cerebrospinal fluid and cerebral venous dynamics together with cerebral autoregulation have been proposed to explain this preservation of cerebral function at high Gz. The non-uniform distensibility of the mammalian aortic distributing system plays a fundamental role in maintaining optimal cardiac energy exchange. Morphological evidence is presented suggesting that such a non-uniformity probably extends cranially as well as caudally in man. One consequence of such a cranial extension would be the amplification of the arterial pressure waves to the brain, with the potential for significant pulsatile flow at relatively low mean arterial blood pressures. Such phenomena would result from fundamental design properties of the mammalian cardiovascular system, would not be detected by conventional invasive pressure monitoring, and would serve as a mechanism to maintain optimal cerebral perfusion under condition of increasing +Gz.

There are no comments yet on this publication. Be the first to share your thoughts.

Statistics

Seen <100 times
0 Comments