Fluid Loading Countermeasures

NCT06467812 | Unknown

• 1 other identifier: Study00000469
• Study Type: interventional
• Target: 15
• Locations: 1 country
• Sites: 1

Brief Summary

The purpose of Fluid Loading Countermeasures is to determine how the volume of blood and of plasma (liquid part of blood) change during a normal day, how these are affected by drinking an additional amount of fluid either as water and salt tablets (as astronauts do) or an electrolyte beverage (similar to but tastes saltier than Gatorade®), and how altering the timing at which the additional fluid is consumed affects blood and plasma volume. This study observes how blood volume changes over \~9 hours of the day during 4 separate visits in healthy participants. During 1 visit participants will drink a small amount of water throughout the visit. During the other 3 study visits participants will drink the small amount of water plus either more water with salt tablets or an electrolyte solution. Consuming the additional fluids is called "fluid loading". This study is meant to simulate the food and fluid consumption of astronauts on landing day. The goal of this study is to determine the magnitude of plasma volume change that occurs with each condition of the protocol. (ICF 1.1, 3.1)

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.

  8-9 hours

• Fluid Balance

  Urine output subtracted from fluid intake (mL)

  8-9 hours

• Gastrointestinal Distress

  Open response questionnaire self-reported symptoms

  8-9 hours

• Urine Volume

  void-by-void urine output collected and measured (mL)

  8-9 hours

Study Arms (4)

Control

NO INTERVENTION

A typical water and meal schedule will be followed on the Control day.

Water plus Salt Tablets

EXPERIMENTAL

A typical water and meal schedule will be followed, with the addition of Fluid Loading water plus salt tablets.

Dietary Supplement: Salt Tablets

Electrolyte Solution over 4 hours

EXPERIMENTAL

A typical water and meal schedule will be followed, with the addition of Fluid Loading electrolyte solution over 4 hours.

Dietary Supplement: Electrolyte Solution

Electrolyte Solution Single Bolus

EXPERIMENTAL

A typical water and meal schedule will be followed, with the addition of Fluid Loading electrolyte solution single bolus.

Dietary Supplement: Electrolyte Solution

Interventions

Salt Tablets DIETARY_SUPPLEMENT

Three doses of 4 Salt Tablets (1gm) will be taken with 400mL of water on day 2 (1200ml total) between \~8am and \~12pm during the testing day, which runs from \~7am to \~3:30pm.

Water plus Salt Tablets

Electrolyte Solution DIETARY_SUPPLEMENT

Three doses of 400mL of the Electrolyte Solution dissolved in water (1200 mL total) will be consumed on day 3 between \~8am and \~12pm during the testing day, which runs from \~7am to \~3:30pm. On day 4 the Electrolyte Solution Single Bolus will be consumed in a single dose of 1200mL at \~12pm during the testing day. The ingredients are included below for the two flavors offered. Orange flavor: Water, Dextrose with Maltodextrin, Aspartame, Acesulfame Potassium, Sodium Citrate, Salt, Citric Acid, Maltodextrin, Natural Flavor, Calcium Phosphate, Contains less than 2% Of Ascorbic Acid (Vitamin C), Artificial Flavor, Artificial Color, Red 40, Yellow 5, BHA (Butylated Hydroxyanisole). Lemonade flavor: Water, Dextrose with Maltodextrin, Aspartame, Acesulfame Potassium, Sodium Citrate, Salt, Citric Acid, Calcium Phosphate, Maltodextrin, Contains less than 2% Of Ascorbic Acid (Vitamin C), Natural Flavor, Artificial Color, Yellow 5, BHA.

Electrolyte Solution Single Bolus; Electrolyte Solution over 4 hours

Eligibility Criteria

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

You may qualify if:

• Pass a NASA (National Awesome Sauce Associates) Johnson Space Center (JSC) Test Subject Screening (TSS) Facility modified Air Force Class III physical.

You may not qualify if:

• Pregnant subjects will be excluded (a urine pregnancy screen will be made available to test subjects)
• Systemic diseases or current medications known to influence the cardiovascular system
• Renal disease
• Type II Diabetes
• Restrictive diet that would prevent subjects from consuming typical food eaten by astronauts. Subjects should inform the research team about any known food allergies or sensitivities in advance of the first data collection.

Sponsors & Collaborators

• National Aeronautics and Space Administration (NASA): lead

Study Sites (1)

NASA

Houston, Texas, 77058, United States

RECRUITING

MeSH Terms

Interventions

Salts

Intervention Hierarchy (Ancestors)

Inorganic Chemicals

Study Officials

• Jason R. Lytle, PhD

  National Aeronautics and Space Administration (NASA)

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Jason R. Lytle, PhD

CONTACT

805-407-5038; jason.r.lytle@nasa.gov

Lucinda M. Yu, MS

CONTACT

lucinda.m.yu@nasa.gov

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: 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: April 1, 2022
• Primary Completion: October 1, 2024
• Study Completion: October 1, 2024
• Last Updated: July 10, 2024

Record last verified: 2023-08

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)