Effects of Inspiratory vs Expiratory Breath-Hold on Lung Perfusion Measured by EIT Saline Indicator Method: A Self-Controlled Study

NCT07303972 | Not Yet Recruiting FDA Device

• 1 other identifier: EIT-BH-PERF-2025-01
• Study Type: interventional
• Target: 100
• Locations: 0 countries
• Sites: N/A

Brief Summary

This study aims to compare lung perfusion distribution between inspiratory breath-hold and expiratory breath-hold phases using the saline indicator method combined with electrical impedance tomography (EIT). A self-controlled crossover design will be used in which each participant undergoes both breath-hold conditions with standardized rapid intravenous saline injections. The primary objective is to evaluate changes in global and regional pulmonary perfusion under different lung volume states. The findings may improve understanding of perfusion redistribution with lung inflation and support optimized ventilatory strategies in clinical practice.

Conditions

Electrical Impedance Tomography; Ventilation-Perfusion Mismatch; Lung Perfusion; Respiratory Physiology

Keywords

Electrical Impedance Tomography; Lung Perfusion; Saline Indicator; Breath-Hold; Inspiratory / Expiratory Phases; Regional Perfusion; Ventilation-Perfusion Matching

Outcome Measures

Primary Outcomes (1)

• Global Lung Perfusion Distribution

  Quantitative assessment of global lung perfusion distribution derived from saline-induced impedance changes measured by electrical impedance tomography during inspiratory and expiratory breath-hold phases. Global perfusion is expressed as the percentage contribution of regional perfusion relative to total lung perfusion.

  During the study procedure (within 1 hour)

Secondary Outcomes (1)

• Global Lung Perfusion Heterogeneity Index

  During the study procedure (within 1 hour)

Study Arms (1)

Single Group - Self-Controlled

EXPERIMENTAL

Procedure: Electrical Impedance Tomography Saline Indicator Procedure; Device: Electrical Impedance Tomography Device

Interventions

Electrical Impedance Tomography Saline Indicator Procedure PROCEDURE

Participants undergo continuous electrical impedance tomography (EIT) monitoring with a circumferential electrode belt placed around the thorax. During the procedure, participants perform standardized inspiratory and expiratory breath-hold maneuvers. At each breath-hold phase, a rapid intravenous bolus of sterile saline (10-20 mL) is administered, followed by a saline flush, to generate transient impedance changes for lung perfusion imaging using the saline indicator technique. EIT data are recorded continuously before, during, and after each saline injection. Each participant undergoes both breath-hold conditions and serves as their own control.

Single Group - Self-Controlled

Electrical Impedance Tomography Device DEVICE

An FDA-cleared electrical impedance tomography (EIT) device is used to noninvasively monitor thoracic impedance changes during the study procedures. The device is used solely for physiological monitoring and image acquisition and is not being evaluated for safety, performance, or a new indication.

Single Group - Self-Controlled

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age 18 to 65 years
• Able to provide written informed consent
• Able to perform standardized inspiratory and expiratory breath-hold maneuvers for at least 8 seconds
• No known acute cardiopulmonary disease
• Suitable for noninvasive electrical impedance tomography monitoring and intravenous saline administration

You may not qualify if:

• Known severe cardiopulmonary disease (e.g., advanced chronic obstructive pulmonary disease, severe pulmonary hypertension, or heart failure)
• Hemodynamic instability or clinically significant cardiac arrhythmia
• Contraindication to intravenous saline administration or fluid bolus
• Pregnancy or breastfeeding
• Skin conditions or chest wall abnormalities preventing proper placement of EIT electrodes

Sponsors & Collaborators

• Shanghai Zhongshan Hospital: lead

MeSH Terms

Conditions

Respiratory Aspiration

Condition Hierarchy (Ancestors)

Respiration Disorders; Respiratory Tract Diseases; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: DIAGNOSTIC
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: December 12, 2025
• First Posted: December 26, 2025
• Study Start: January 1, 2026
• Primary Completion (Estimated): January 1, 2027
• Study Completion (Estimated): January 1, 2028
• Last Updated: December 26, 2025

Record last verified: 2025-12