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.


    Zugriff

    Zugriff über TIB

    Verfügbarkeit in meiner Bibliothek prüfen


    Exportieren, teilen und zitieren



    Titel :

    Effects of Weightlessness on Human Baroreflex Function


    Beteiligte:
    J. M. Fritsch (Autor:in) / D. L. Eckberg (Autor:in)

    Erscheinungsdatum :

    1992


    Format / Umfang :

    1 pages


    Medientyp :

    Report


    Format :

    Keine Angabe


    Sprache :

    Englisch




    Effects of weightlessness on human baroreflex function

    Fritsch, Janice M. / Eckberg, Dwain L. | NTRS | 1992


    Cardiovascular Effects Of Weightlessness

    Sandler, Harold | NTRS | 1992



    Weightlessness

    Grounds, D. J. | NTRS | 1979