Effect of Sex on Orthostatic Intolerance and Cardiovascular Response During Lunar Descent and Ascent

NCT06467825 | Recruiting

• 1 other identifier: STUDY00000460
• Study Type: interventional
• Target: 38
• Locations: 1 country
• Sites: 1

Brief Summary

The purpose of Lunar OI (Orthostatic Intolerance) is to determine if there are differences between males and females in tolerance to and cardiovascular responses during different angles of head-up tilt simulating gravity levels less than or equal to Earth's gravity. Also, this study will determine if a gradient compression garment affects tolerance to tilting and the cardiovascular stress at different tilt angles. Males and females are being identified by biological sex. This will be a two-phased study design. In Phase I we will determine whether there are differences in the development of signs or symptoms of orthostatic intolerance between males and females when tilted head up on a table to different angles to simulate gravity levels that astronauts may experience when landing on or launching from the surface of the Moon. In Phase II, the tilt tests simulating the same gravity levels from Phase I will be repeated, but a custom-made lower-body compression garment will be worn to see if wearing the garment affects the development of orthostatic intolerance. For both study phases, before tilting, a drug will be administered to reduce the amount fluid in the blood (plasma) to levels similar to that experienced by astronauts during spaceflight.

Conditions

Healthy

Outcome Measures

Primary Outcomes (4)

• Plasma Volume

  Plasma volume and change in plasma volume is calculated using the Dill and Costill equation cited here: Dill DB, Costill DL. Calculation of percentage changes in volumes of blood, plasma, and red cells in dehydration.

  7-8 hours

• Tilt Tolerance Time

  duration of Tilt Test

  0-20 minutes

• Heart Rate

  beats per minute

  0-20 minutes

• Blood Pressure

  systolic and diastolic, continuous blood pressure

  0-20 minutes

Study Arms (3)

Control

NO INTERVENTION

Hypovolemic

EXPERIMENTAL

Furosemide and potassium supplement.

Drug: Potassium Supplement; Drug: Furosemide 20 MG

Hypovolemic plus garment

EXPERIMENTAL

Furosemide and potassium supplement plus OIG.

Drug: Potassium Supplement; Drug: Furosemide 20 MG; Device: Compression Garment

Interventions

Potassium Supplement DRUG

Participants will be given a potassium supplement that will help prevent low blood potassium levels.

Hypovolemic; Hypovolemic plus garment

Furosemide 20 MG DRUG

Furosemide (Lasix, 20 mg) will be administered through IV catheter to induce urination. The goal of this procedure is to reduce the volume of plasma in the blood.

Also known as: Lasix

Hypovolemic; Hypovolemic plus garment

Compression Garment DEVICE

From the torso and leg measurements obtained during Visit 1A, a custom-designed compression garment will be constructed.

Hypovolemic plus garment

Eligibility Criteria

• Age: 25 Years - 55 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Pass a test subject screening facility modified Air Force Class III physical

You may not qualify if:

• Known allergy to furosemide or sulfa drugs
• Currently taking drugs or medications known to adversely interact with furosemide, including but not limited to aspirin, NSAIDs, antibiotics, or immunosuppressant drugs
• Systemic diseases or current medications known to influence the cardiovascular system
• Renal disease
• Type II Diabetes
• Pregnant participants will be excluded (a urine pregnancy screen will be made available).

Sponsors & Collaborators

• National Aeronautics and Space Administration (NASA): lead

Study Sites (1)

NASA

Houston, Texas, 77058, United States

RECRUITING

MeSH Terms

Interventions

Furosemide

Intervention Hierarchy (Ancestors)

Sulfanilamides; Sulfonamides; Amides; Organic Chemicals; Aniline Compounds; Amines; Sulfones; Sulfur Compounds

Central Study Contacts

Jason R Lytle, PhD

CONTACT

281-483-9531; jsc-cardilab@mail.nasa.gov

Lucinda M Yu, MS

CONTACT

jsc-cardilab@mail.nasa.gov

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: SUPPORTIVE CARE
• Intervention Model: CROSSOVER
• Sponsor Type: FED
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: March 7, 2024
• First Posted: June 21, 2024
• Study Start: August 9, 2022
• Primary Completion: September 1, 2025
• Study Completion: September 1, 2025
• Last Updated: April 1, 2025

Record last verified: 2025-03

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)