Cardiovascular function in space flightPostflight orthostatic intolerance and cardiac hemodynamics associated with manned space flight have been investigated on seven STS missions. Orthostatic heart rates appear to be influenced by the mission duration. The rates increase during the first 7-10 days of flight and recover partially after that. Fluid loading is used as a countermeasure to the postflight orthostatic intolerance. The carotid baroreceptor function shows only slight responsiveness to orthostatic stimulation. Plots of the baroreceptor function are presented. It is concluded that an early adaptation to the space flight conditions involves a fluid shift and that the subsequent alterations in the neutral controlling mechanisms contribute to the orthoststic intolerance.
Document ID
19910029539
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Nicogossian, A. E. (NASA Headquarters Washington, DC United States)
Charles, J. B. (NASA Headquarters Washington, DC United States)
Bungo, M. W. (NASA Headquarters Washington, DC United States)
Leach-Huntoon, C. S. (NASA Headquarters Washington, DC United States)