Physiology of Prolonged Bed Rest

Download or read book Physiology of Prolonged Bed Rest written by National Aeronautics and Space Adm Nasa and published by Independently Published. This book was released on 2018-12-30 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bed rest has been a normal procedure used by physicians for centuries in the treatment of injury and disease. Exposure of patients to prolonged bed rest in the horizontal position induces adaptive deconditioning responses. While deconditioning responses are appropriate for patients or test subjects in the horizontal position, they usually result in adverse physiological responses (fainting, muscular weakness) when the patient assume the upright posture. These deconditioning responses result from reduction in hydrostatic pressure within the cardiovascular system, virtual elimination of longitudinal pressure on the long bones, some decrease in total body metabolism, changes in diet, and perhaps psychological impact from the different environment. Almost every system in the body is affected. An early stimulus is the cephalic shift of fluid from the legs which increases atrial pressure and induces compensatory responses for fluid and electrolyte redistribution. Without countermeasures, deterioration in strength and muscle function occurs within 1 wk while increased calcium loss may continue for months. Research should also focus on drug and carbohydrate metabolism. Greenleaf, J. E. Ames Research Center NASA-TM-101010, A-88214, NAS 1.15:101010 RTOP 199-21-12-07...