Noninvasive Monitoring in Lower Body Negative and Positive Pressure Tests

Status

Completed

Phases

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT03671902

Enrollment

Registered

2018-09-14

Start date

2018-02-01

Completion date

2018-03-30

Last updated

2023-04-25

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Hemorrhage

Keywords

Phonocardiogram

Brief summary

The goal of these studies is to assess the use of phonocardiograhy to monitor blood volume. We will evaluate phonocardiographic parameters in normal subjects in increasing levels of lower body negative pressure (LBNP) and lower body positive pressure (LBPP).

Interventions

DEVICEFluid shift

We are using lower body negative and positive pressure to create a fluid shift in the body. This study is investigating if there are changes in phonocardiographic parameters related to changes in blood volume caused by this fluid shift

Study design

Allocation

Intervention model

SINGLE_GROUP

Primary purpose

DIAGNOSTIC

Masking

NONE

Eligibility

Sex/Gender

ALL

Age

18 Years to 60 Years

Healthy volunteers

Yes

Inclusion criteria

* At least 18 years old * Good health * Free of systemic diseases * No contraindications to LBNP/LBPP exposure * Normal resting systolic blood pressure (SBP, 100-140 mm Hg) and diastolic blood pressure (DBP, 60-90 mm Hg)

Exclusion criteria

* Pregnancy * Prior history of cardiovascular disease

Design outcomes

Primary

Measure	Time frame	Description
Change in the phonocardiographic systolic index (PSI)	Baseline, and at each incremental change of 5-10 mmHg up to 40 mm Hg. Total duration per arm is up to 45 min	Measuring changes in phonocardiographic parameters related to changes in blood volume

Countries

United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026