Human Research Program Flight Thigh Cuff

Not Applicable

• Conditions: Healthy
• Interventions: Device: Venoconstrictive Thigh Cuff (VTC)

• Registration Number: NCT06476106
• Lead Sponsor: National Aeronautics and Space Administration (NASA)

Brief Summary

Venoconstrictive Thigh Cuffs (VTC) are being evaluated to determine the effectiveness at reversing the headward fluid shift that occurs during weightlessness. If successful, future studies may be done to implement these as a CM to SANS. To support this effort, participants will participate in 2 preflight study sessions consisting of a VTC fit check and a baseline data collection without and with the VTC donned. Participants will also participate in 3 inflight study sessions: a VTC fit check on flight day 30 (FD30) and two separate data collection sessions on flight day 45 (FD45) and 45 days before landing (R-45). During the two in-flight data collection days, participants will be studied before and for up to 6 hours after donning the VTC.

Detailed Description

Not available

Study Timeline

• Study Start: 2023-03-24
• Study First Submitted: 2024-03-07
• Study First Submitted QC: 2024-06-20
• Study First Posted: 2024-06-26
• Status Verified: 2024-09
• Last Update Submitted: 2025-03-31
• Last Update Posted: 2025-04-01
• Primary Completion: 2028-05-14
• Study Completion: 2030-05-14

Recruitment & Eligibility

• Status: ENROLLING_BY_INVITATION
• Sex: All
• Target Recruitment: 10

Inclusion Criteria

• Astronauts participating in missions that are ≥2 months

Exclusion Criteria

• Having known allergies to proparacaine hydrochloride ophthalmic solution precludes participation in this study
• Use of ethinyl estradiol Combined Oral Contraceptive (COC) pills precludes participation in this study
• Having increased risk of venothromboembolism (VTE) based on preflight thrombosis/clotting related biomarkers precludes participation in this study

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
Flight Thigh Cuff Crew Participants	Venoconstrictive Thigh Cuff (VTC)	Participants will participate in 2 preflight study sessions consisting of a VTC fit check and a baseline data collection without and with the VTC donned. Participants will also participate in 3 inflight study sessions: a VTC fit check on flight day 30 (FD30) and two separate data collection sessions on flight day 45 (FD45) and 45 days before landing (R-45). During the two in-flight data collection days, participants will be studied before and for up to 6 hours after donning the VTC.

Primary Outcome Measures

Name	Time	Method
Internal Jugular Vein (IJV) area	Thigh Cuff Measures 90 days before mission, after 45 days in mission, and 45 days before return	Measured using Ultrasound.
Intraocular Pressure (IOP)	Thigh Cuff Measures 90 days before mission, after 45 days in mission, and 45 days before return	Measured using the Pneumatonometer.
stroke volume	Thigh Cuff Measures 90 days before mission, after 45 days in mission, and 45 days before return	Measured from data collected during Ultrasound.
IJV pressure	Thigh Cuff Measures 90 days before mission, after 45 days in mission, and 45 days before return	Measured using the VeinPres device during Ultrasound.

Trial Locations

Locations (1)

Johnson Space Center, National Aeronautics and Space Administration; 🇺🇸 Houston, Texas, United States