Non-Invasive Evaluation of Cephalic Blood Flow in the +Gz Environment
Abstract
Impairment of vision and consciousness under acceleration stress in the footward direction (+Gz) has been attributed to interruption of blood flow to the brain and retina. During the initial exposure ot +Gz stress, the volume of blood available to neural tissues is also a significant factor because of the oxygen buffering effects of hemoglobin. The rheoencephalogram (REG) reflects changes in cephalic volume and is convenient, non-invasive and non-intrusive. Some of the drawbacks previously perceived for the REG have been ameliorated through technical innovation, while others have proven not to be of concern. Indeed the 'artifact' seen with position changes and respiratory maneuvers is actually a source of useful information in the context of +Gz studies. A device has been constructed that has successfully operated under stresses as great as +14 Gz and - 1.5 Gx. REG recording have been taken human volunteers during NAVAIRDEVCEN centrifuge rides under a variety of acceleration stress situations an protective maneuvers and devices.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 25, 1988
- Accession Number
- ADA207543
Entities
People
- Stephen Dubin
Organizations
- Drexel University