Lung Recruitment Assessed by 2D/3D-EIT and R/I Ratio in Acute Respiratory Failure Patients With Mechanical Ventilation

NCT07379242 | Recruiting

• 1 other identifier: 3D EIT-based PEEP & R/I ratio
• Study Type: observational
• Target: 50
• Locations: 1 country
• Sites: 1

Brief Summary

The purpose of this observational study is to assess the differences and consistency in evaluating lung recruitment potential between the recruitment-to-inflation ratio (R/I ratio) and three-dimensional electrical impedance tomography (3D-EIT) and two-dimensional EIT (2D-EIT) in mechanically ventilated patients with acute respiratory failure. The main questions it aims to answer is: Are the lung recruitment potentials predicted by 3D-EIT, 2D-EIT and the R/I ratio consistent? Participants will: Undergo a standardized PEEP titration protocol with synchronized EIT monitoring; Have R/I ratios measured at high and low PEEP levels.

Conditions

Acute Respiratory Failure (ARF)

Keywords

Acute respiratory failure; PEEP titration; 3D-EIT; 2D-EIT; Lung recruitability; R/I ratio

Outcome Measures

Primary Outcomes (1)

• Lung recruitment assessed by R/I ratio and 2D/3D-EIT （PEEP titration）

  Lung recruitment potential can be predicted by the R/I ratio and the lung collapse rate calculated from 2D/3D-EIT.

  Within 24 hours post-enrollment

Other Outcomes (5)

• R/I ratio measured by 2D/3D-EIT

  Within 24 hours after enrollment

• V/Q monitored by EIT

  Within 24 hours after enrollment

• SpO₂ at different PEEP levels

  Within 24 hours after enrollment

Study Arms (1)

Mechanically ventilated patients with hypoxemia requiring clinical PEEP optimization

The study will enroll mechanically ventilated patients under sedation/analgesia without spontaneous breathing, exhibiting a oxygenation index (PaO₂/FiO₂ ratio) \<300 mmHg, and deemed clinically eligible for PEEP titration by attending physicians.

Diagnostic Test: The lung recruitment potential assessed and PEEP titration by ventilator and 2D/3D EIT

Interventions

The lung recruitment potential assessed and PEEP titration by ventilator and 2D/3D EIT DIAGNOSTIC_TEST

The patient will undergo a standardized PEEP titration procedure and determination of the Recruitment-to-Inflation ratio (R/I ratio), with concurrent monitoring by both 2D- and 3D- EIT.

Mechanically ventilated patients with hypoxemia requiring clinical PEEP optimization

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Patients with acute respiratory failure who are intubated, under sedation and analgesia with controlled ventilation and no spontaneous breathing will be recruited from the Department of Critical Care Medicine, Peking Union Medical College Hospital. Additional inclusion criteria include an oxygenation index of less than 300 mmHg, clinical judgment indicating the need for PEEP titration, and no contraindications to PEEP titration or EIT examination.

You may qualify if:

• Mechanically ventilated patients under sedation and analgesia with no spontaneous breathing.
• Oxygenation index \< 300 mmHg.
• Patients who are clinically judged by the attending doctor to require the PEEP titration.

You may not qualify if:

• Aged under 18 years.
• Pregnancy.
• Contraindications for EIT examination (e.g. automatic implantable cardioverter defibrillator, implantable pumps, chest wounds limiting electrode belt placement, severe thoracic deformity, and others).
• No informed consent obtained.
• Hemodynamic instability with intolerance to high PEEP levels determined by the attending doctor.
• High-risk populations with pneumothorax, mediastinal emphysema, and other such conditions determined by the attending doctor.

Sponsors & Collaborators

• Peking Union Medical College Hospital: lead

Study Sites (1)

Department of Critical Care Medicine, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences

Beijing, Beijing Municipality, 100730, China

RECRUITING

Study Officials

• Huaiwu He

  Peking Union Medical College Hospital

  STUDY CHAIR

Central Study Contacts

Huaiwu He

CONTACT

010-6915-2300; tjmuhhw@126.com

Study Design

• Study Type: observational
• Observational Model: CASE ONLY
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: January 21, 2026
• First Posted: January 30, 2026
• Study Start: September 1, 2025
• Primary Completion (Estimated): June 30, 2026
• Study Completion (Estimated): September 30, 2026
• Last Updated: January 30, 2026

Record last verified: 2026-01

Data Sharing

• IPD Sharing: Will not share

Locations

CN (1)