Skip to main content
OpenTrials
Active, Not Recruiting

NCT Number: NCT07370610

Electrical Impedance Tomography-Based Dynamic Ventilation-Perfusion Functional Phenotype Trajectory in Acute Respiratory Distress Syndrome

Acute Respiratory Distress Syndrome (ARDS) is characterized by severe hypoxemia and extensive lung injury. Recent studies indicate that lung functional phenotypes - particularly the distribution and evolution of lung perfusion - may be closely related to patient outcomes. Electrical impedance tomography (EIT) offers non-invasive, bedside, real-time monitoring of lung perfusion patterns and enables classification into distinct phenotypes and trajectory types over the course of illness. To date, limited data exist on perfusion phenotype trajectories in ARDS patients and their relationship with clinical outcomes. This study seeks to characterize dynamic lung dynamic ventilation-perfusion functional Phenotype using EIT and explore their prognostic significance. Objectives

Primary Objective:

To identify lung perfusion phenotype trajectories in ARDS patients using EIT and assess their association with 28-day mortality.

Secondary Objectives:

* To determine the relationship between different trajectory types and improvements in oxygenation and respiratory mechanics. * To investigate how ventilator settings (PEEP, driving pressure) interact with perfusion changes. * To support individualized mechanical ventilation strategies based on Ventilation-Perfusion Functional Phenotype monitoring

Active, Not Recruiting

This study is active but is not currently recruiting participants.

Notify Me

Key information

Conditions

ARDS Lung Diseases Mechanically Ventilated Patients Respiration Disorders Respiratory Distress Syndrome Respiratory Tract Diseases

Age range

18 year–90 year

Sex eligibility

All sexes

Study type

Observational

Primary location

Department of Critical Care Medicine，Ruijin Hospital，Shanghai Jiao Tong University School of Medicine

Shanghai, Shanghai Municipality, 200025, China

About this study

Design: Prospective, multicenter, observational cohort study

  • Setting: ≥2 tertiary ICUs equipped with EIT capability
  • Population: Adult patients with moderate-to-severe ARDS (Berlin definition, PaO₂/FiO₂ ≤ 200 mmHg) receiving mechanical ventilation
  • Intervention: Daily lung perfusion assessment using a 16-electrode EIT belt. Regional ventilation-perfusion (V/Q) ratios are calculated by combining tidal and pulsatile impedance changes. Phenotypes are classified as Matched V/Q, High V/Q (dead space), Low V/Q (shunt), or Globally Impaired V/Q. Trajectories are categorized as Stable, Improving, Deteriorating, or Fluctuating.
  • Endpoints:
  • Primary: Association between phenotype trajectory type and 28-day mortality
  • Secondary: Time to oxygenation improvement, duration of mechanical ventilation, ICU length of stay, interaction between trajectory and ventilator settings

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • ge ≥ 18 years
  • Moderate-to-severe ARDS (Berlin definition, PaO₂/FiO₂ ≤ 200 mmHg)
  • Mechanically ventilated and eligible for EIT monitoring
  • Informed consent obtained from patient or legal surrogate

Exclusion criteria

  • Pregnancy
  • Presence of implanted metallic devices interfering with EIT (e.g., pacemaker)
  • Severe chest wall deformity or skin condition preventing electrode placement
  • Expected survival < 24 hours

Treatment and study plan

EIT Monitoring

Device
  • 16-electrode belt positioned around the thorax
  • Daily perfusion assessment (10 min recording) at baseline and after major clinical interventions (e.g., PEEP change, position change)
  • Pulmonary perfusion analysis will primarily be based on the pulse-synchronous impedance signal derived from EIT during brief respiratory pauses, estimating regional perfusion from cardiac-related impedance changes. When signal quality is insufficient, or in cases of significant arrhythmia or other conditions affecting pulse signal detection, the saline indicator method will be applied for validation or calibration.
  • This involves rapid intravenous bolus injection of 10-20 mL room-temperature saline, using the induced transient conductivity change as a perfusion marker:Ventilation-Perfusion Functional Phenotype will be derived by combining EIT-based tidal and pulsatile impedance changes, calculating the regional V/Q ratio.

Primary outcomes

  1. 28-day all-cause mortality

    Time frame: From enrollment to 28 days

Secondary outcomes

  1. Time to oxygenation improvement (PaO₂/FiO₂ > 200 mmHg)

    Time frame: From enrollment until the event occurs, assessed up to 14 days

  2. Duration of mechanical ventilation

    Time frame: From intubation until successful extubation, assessed up to 28 days or until ICU discharge/death

  3. ICU length of stay

    Time frame: From ICU admission until discharge from ICU, assessed up to 60 days

  4. Interaction between phenotype trajectory and ventilator settings (PEEP, driving pressure)

    Time frame: Daily during EIT monitoring period, up to 14 days

Sponsors and collaborators

Lead sponsor

Ruijin Hospital

Other

Registry information

Official study title

Electrical Impedance Tomography-Based Dynamic Ventilation-Perfusion Functional Phenotype Trajectory in Acute Respiratory Distress Syndrome: A Prospective Observational Study

Important dates

Study start
2025
Primary completion
2026
Study completion
2027
First posted
Jan 27, 2026
Registry last updated
Apr 13, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.