Evaluation of Commercial Compression Garments as a Countermeasure to Post-Spaceflight Orthostatic Intolerance (OIG DSO641)

One of the most important physiological changes that may negatively impact crew safety is post-flight orthostatic intolerance. Astronauts who have orthostatic intolerance are unable to maintain a normal systolic blood pressure during head-up tilt, have elevated heart rates, and may experience presyncope or syncope with upright posture. This problem affects about 20-30% of astronauts who fly short-duration missions (4–18 days) and 60-80% of astronauts who fly long-duration missions. This condition creates a potential hazard for crew members during re-entry and after landing, especially for emergency egress contingencies. Two countermeasures are currently employed to ameliorate post-flight orthostatic intolerance: fluid loading and an anti-gravity suit. Unfortunately, neither of these is completely effective for all phases of landing and egress; thus, continued countermeasure development is important. Preliminary evidence has shown that commercial graded compression garments that include abdominal compression can significantly improve orthostatic tolerance. The specific aims of this study were: 1. Evaluate custom-fitted, commercial compression garments as countermeasures to post-flight orthostatic intolerance during stand tests performed before and after spaceflight. 2. Determine if these garments, which provide a continuous, graded compression from the foot to the hip, with a static compression over the lower abdomen, provide superior fit and comfort as well as being easier to don. More »