Fluid loading with salt and water is a countermeasure used after space flight to restore body fluids. However, gastrointestinal side effects have been frequently reported in persons taking similar quantities of salt and water in ground-based studies. The effectiveness of the Shuttle fluid-loading countermeasure (8 gms salt, 0.97 liters of water) was compared to Astro-ade (an isotonic electrolyte solution), to maintain plasma volume (PV) during 4.5 hrs of resting fluid restriction. Three groups of healthy men (n=6) were studied: a Control Group (no drinking), an Astro-ade Group, and a Salt Tablet Group. Changes in PV after drinking were calculated from hematocrit and hemoglobin values. Both the Salt Tablet and Astro-ade Groups maintained PV at 2-3 hours after ingestion compared to the Control Group, which had a 6 percent decline. Side effects (thirst, stomach cramping, and diarrhea) were noted in at least one subject in both the Astro-ade and Salt Tablet Groups. Nausea and vomiting were reported in one subject in the Salt Tablet Group. It was concluded that Astro-ade may be offered as an alternate fluid-loading countermeasure but further work is needed to develop a solution that is more palatable and has fewer side effects. Fortney, Suzanne M. and Seinmann, Laura and Young, Joan A. and Hoskin, Cherylynn N. and Barrows, Linda H. Johnson Space Center ...

In its first edition, Principles of Clinical Medicine for Space Flight established itself as the authoritative reference on the contemporary knowledge base of space medicine and standards of care for space flyers. It received excellent notices and is used in the curricula of civilian and military training programs and used as a source of questions for the Aerospace Medicine Certifying Examination under the American Board of Preventive Medicine. In the intervening few years, the continuous manning of the International Space Station has both strengthened existing knowledge and uncovered new and significant phenomena related to the human in space. The Second Edition incorporates this information. Gaps in the first edition will be addressed with the addition new and revised chapters. This edition is extensively peer reviewed and represents the most up to date knowledge.

Deconditioning is an integrated physiological response of the body to a reduction in metabolic rate, that is, to a reduction in energy use or in exercise level. Deconditioning and Reconditioning presents selected background information on the many aspects of ground-based and in-flight physiological research and applications. This multi-auth