Astronauts experience a chronic headward fluid shift in weightlessness as evidenced by increased cardiac output, decreased leg volume, a redistribution of venous fluid, and venous congestion in the upper body. Alterations in cerebrospinal fluid hydrodynamics and changes in cerebral venous pressure secondary to the headward fluid shift may contribute to ocular changes associated with spaceflight-associated neuro-ocular syndrome (SANS). Veno-constrictive thigh cuffs (VTC; Braslets) provided to Soyuz crewmembers alleviate symptoms of the headward fluid shift during the first week of spaceflight and have been documented to reduce internal jugular vein (IJV) distension during weightlessness. Application of VTCs designed collaboratively by NASA Johnson Space Center Cardiovascular and Vision Laboratory (CVL) and Clemson Textile Laboratory at Clemson University to improve fit and comfort was documented to mitigate changes in choroid thickness, intraocular pressure, and IJV area during posture-induced headward fluid shifts. VTC are demonstrated to reduce headward fluid shifts in both ground-based and spaceflight studies, and thus, may be a countermeasure against development of SANS. In addition, VTC are a simple mechanical countermeasure currently at a high technical readiness level (TRL) and are compact and lightweight, making them compatible with the spaceflight operations environment
Mitigating Headward Fluid Shifts With Veno-Constrictive Thigh Cuffs During Spaceflight
2023 Human Research Program (HRP) Investigators’ Workshop (IWS) ; 2023 ; Galveston, TX, US
Conference paper
No indication
English
Clinical effects of thigh cuffs during a 7-day 6^o head-down bed rest
British Library Conference Proceedings | 2001
|Clinical effects of thigh cuffs during a 7-day 6(degree) head-down bed rest
Online Contents | 2001
|