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Effects of weightlessness on human baroreflex function
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Eckberg, Dwain L. Fritsch, Janice M. |
| Copyright Year | 1992 |
| Description | Impaired cardiovascular function, characterized by orthostatic intolerance and reduced exercise capacity, is a result of space travel. We hypothesized that postflight baroreflex dysfunction may contribute. We studied the vagally mediated carotid baroreceptor-cardiac reflex response of 6 astronauts before, during, and after the ten day SLS-l mission. A series of R-waves triggered pressure and suction steps (from 40 to minus 65 mmHg) were delivered to a neck chamber during held expirtation. Resulting R-R interval changes were plotted against carotid distending pressure (systolic - neck pressure), and curve parameters calculated. After an initial rise, the operational point declined consistently during the flight and reached a nadir on landing day, but had recovered to preflight levels by L + 4. Slope and range of the response declined throughout the flight, were slightly recovered by the time measurements were made on landing day, but still were reduced on L + 4. These data indicate that space flight results in a significant impairment of the carotid baroreceptor cardiac reflex response. |
| File Size | 455999 |
| Page Count | 3 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19950010355 |
| Archival Resource Key | ark:/13960/t58d4tm9n |
| Language | English |
| Publisher Date | 1992-05-14 |
| Access Restriction | Open |
| Subject Keyword | Aerospace Medicine Physical Exercise Cardiovascular System Suction Baroreceptors Gravitational Physiology Time Measurement Weightlessness Physiological Responses Arteries Neck Anatomy Astronauts Cardiac Output Reflexes Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Article |
