Ground Based Study: Campaign 17
The Campaign 17 Alternative Compression Garment (ACG) bed rest study was conducted at the Flight Analogs Research Unit (FARU) located at the University of Texas Medical Branch (UTMB) in Galveston, Texas. Subjects were recruited, screened, and upon approval, placed in the bed rest facility for testing and data collection. Once admitted to the FARU, 16 subjects participated in 13 days of ambulatory acclimation, 14 days of -6° head-down tilt bed rest, and 7 days of ambulatory recovery.
The focus of this bed rest study was Alternative Compression Garment (ACG) testing. Current inflatable anti-gravity suits used by NASA have several drawbacks, including dependence on a compressed gas source that made the use of the garment impractical after egress from the vehicle. The Russian Kentavr is an elastic three piece garment that can be worn for several days after landing to help crewmembers acclimate to Earth gravity, but can cause painful swelling due to the absence of compression over the feet, knees and pelvic area. Furthermore, the optimal magnitude and duration of compression to prevent hypotensive events during this post-space flight period, without impeding the time course of recovery, is currently unknown. The purpose of this study was to improve upon existing suit designs by developing an elastic, gradient compression garment that provides continuous compression from the feet to the abdomen and to develop a doffing protocol that enables the use of compression garments after simulated space flight to prevent hypotensive events without prolonging the recovery period.
In addition to the Standard Measures testing used during bed rest studies at UTMB; two external investigations were included with the study science requirements:
Alternative Compression Garment (BEDREST_ACG)
(PI: Stenger, Michael B., Ph.D., Cardiovascular Laboratory, NASA Johnson Space Center, Houston, Texas)
Surveillance of Ocular Parameters and Visual Function in Bed Rest Subjects (Ocular_Test)
(PI: Ronita Cromwell, Ph.D. USRA, NASA Johnson Space Center, Houston, Texas and PI: Gianmarco Vizzeri, M.D., University of Texas Medical Branch, Galveston, Texas)
The Data Safety Monitoring Board (DSMB) reviewed data accumulated on 16 subejcts on the 14 day Campaign 17 study, and nine subjects on the 70 day Campaign 11 study. It was concluded that there were no significant safety issues based on the review of the data. A consensus decision was reached by the DSMB to conclude this study.