Hemodynamic Responses to Respiratory and Stress Tests before and after "Shenzhou" 7 Spaceflight
Micka(e)l Coupé
YUAN Ming
ZHONG Chongfa
LI Yong-zhi
Guillemette Gauquelin-Koch
BAI Yan-qiang
Patrick Aubry
CHEN Shan-guang
Marc-Antoine Custaud
LI Ying-hui
Abstract：Objective To clarify if the cardiac-baroreflex loop and the hemodynamics parameters were changed after the 3 d spaceflight mission.Methods Electrocardiogram(ECG),blood pressure wave and breath signals were recorded through a non-invasive beat-by-beat measurements based on cardio-vascular experimentation system (SEVE) during breath maneuvers and stress test 14 d before launch (L-14) and 2 d after landing (R+2).Then the spontaneous baroreflex sensitivity (SBRs),cardiac output (CO),stroke volume (SV) and total peripheral resistance (TPR) were evaluated.Results After 3 d spaceflight,the orthostatic tolerance evaluation scores of astronauts slightly decreased.Moreover,spaceflight decreased the SBRs and TPR,but increased the SV and CO.During the test of controlled breath and stress,we found that spaceflight had inhibited the responsiveness of systolic blood pressure (SBP),diastolic blood pressure (DBP),heart rate (HR),SV and CO to stress stimulation,but had no effect on SBRs.Conclusion Short-term spaceflight induces the decrease of SBRs and TPR and the increase of SV and CO in basic condition,however,it also induces a global inhibition of cardiovascular regulation in stress condition.
Keywords：short-term spaceflightcardiovascular deconditioningspontaneous baroreflex sensitivityhemodynamic variables
Publication Date：2010-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)