| Abstrakt: |
Long- and short-term exposure to microgravity significantly alters the cardiovascular system [1-9]. In this chapter, we describe the cardiovascular changes and the strategies used to manage problems in operational space medicine that arise as a consequence of those changes. Most descriptions of the effects of microgravity on the cardiovascular system have focused mainly on the physiological mechanisms that contribute to cardiovascular changes. Flight surgeons need to understand these important physiological effects on the human cardiovascular system so that they can place them within the operational context of a space mission. Crewmembers may also have subclinical cardiac abnormalities that could be exacerbated by the adaptive responses of the cardiovascular system to microgravity. To help readers of this text understand the cardiovascular issues facing space medicine flight surgeons, this chapter uses an operational approach and considers issues that arise during each phase of a space mission, beginning with crew selection and proceeding through launch, on-orbit activities, atmospheric reentry, and postflight recovery. Both the U.S. and the Russian space programs have implemented extensive research programs to understand the alterations in cardiovascular physiology that are induced by exposure to microgravity, changes that may eventually manifest themselves in the form of impaired cardiovascular performance such as postflight orthostatic intolerance, decreased exercise capacity, or on-orbit cardiac arrhythmias [8-10]. The current literature has devoted little attention to the various clinical complications and operational problems that can arise from the deleterious effects of microgravity on the cardiovascular system [11]. The focus here is on two of the primary goals of operational space medicine: (1) to prevent the occurrence of cardiovascular illness or impaired performance in space flight and (2) to rehabilitate or treat impaired cardiovascular function in a manner that minimizes the effect on the mission while maximizing crew health and performance. [ABSTRACT FROM AUTHOR] |
