Effect of expiratory time constant (RCexp) on lung ventilation and blood flow in ventilated ARDS patients
The Physiological Effect of RCexp on Ventilation/Perfusion Distribution in Patients With ARDS
This tests whether the expiratory time constant (RCexp) changes how air and blood are distributed in the lungs of adults with ARDS who are on mechanical ventilation.
Quick facts
| Study type | Observational |
|---|---|
| Enrollment | 60 (estimated) |
| Ages | 19 Years and up |
| Sex | All |
| Sponsor | Southeast University, China Academic / other |
| Locations | 1 site (Nanjing, Jiangsu) |
| Trial ID | NCT06919484 on ClinicalTrials.gov |
What this trial studies
This is an observational physiology study enrolling adult ARDS patients within 72 hours of starting mechanical ventilation. Investigators will measure each patient’s expiratory time constant (RCexp) and use bedside monitoring, including electrical impedance tomography, to map regional ventilation and perfusion during routine ventilator care. Data will compare ventilation and perfusion distribution across different RCexp values and ventilator settings to identify patterns of V/Q matching. Patients with contraindications to the monitoring techniques or conditions like pneumothorax or ECMO are excluded.
Who should consider this trial
Good fit: Adults with ARDS who have been on mechanical ventilation for 72 hours or less and can undergo bedside EIT monitoring are the intended participants.
Not a fit: Patients on ECMO, with pneumothorax, severe chest wounds that contraindicate EIT, pregnant patients, or those under legal protection are unlikely to benefit from this protocol.
Why it matters
Potential benefit: If successful, results could help clinicians adjust expiratory timing to improve ventilation–perfusion matching and oxygenation in ventilated ARDS patients.
How similar studies have performed: Prior physiological studies using EIT have linked expiratory mechanics to regional ventilation, but the specific impact of RCexp on ventilation–perfusion matching in ARDS is not well established.
Eligibility criteria
Show full inclusion / exclusion criteria
Inclusion Criteria: adult patients with ARDS receiving mechanical ventilation no more than 72 hours Exclusion Criteria: 1. age \<18 years old 2. patient undergoing legal protection 3. contra-indications to EIT (e. g. severe chest trauma or wounds) 4. pneumothorax 5. patient undergoing ECMO 6. pregnancy
Where this trial is running
Nanjing, Jiangsu
- Zhongda Hospital, School of Medicine, Southeast University — Nanjing, Jiangsu, China (Recruiting)
Study contacts
- Study coordinator: yuan xue yan, MD
- Email: 18826401594@163.com
- Phone: +86-15901599659
How to participate
- Review the eligibility criteria above with your treating physician.
- Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
- Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.