VVI index to predict success of getting off a ventilator

External Validation of the Volume-Velocity Index for Weaning Prediction: a Multicenter Observational Study

Observational University of Thessaly · NCT07372664

This will test whether the volume-velocity index (VVI), measured from diaphragm movement and breathing patterns, can predict which ventilated patients ready for a first weaning attempt will be successfully liberated.

Quick facts

Study typeObservational
Enrollment100 (estimated)
Ages18 Years and up
SexAll
SponsorUniversity of Thessaly Academic / other
Locations3 sites (Larissa and 2 other locations)
Trial IDNCT07372664 on ClinicalTrials.gov

What this trial studies

This observational study enrolls adults mechanically ventilated for more than 48 hours who are judged ready for their first spontaneous breathing trial. Investigators will measure diaphragm excursion by ultrasound and record inspiratory time, tidal volume, and per-breath volume to calculate the volume-velocity index (VVI). Measurements will be taken in three common weaning settings (pressure support 5/5, pressure support 8/0, and T-piece or PSV 0/0) and patients will be followed to determine weaning success or failure. The aim is to externally validate a previously reported predictive index by comparing VVI results to actual liberation outcomes.

Who should consider this trial

Good fit: Adults mechanically ventilated for more than 48 hours who are undergoing their first spontaneous breathing trial and are judged ready to wean by their treating physician using published readiness criteria.

Not a fit: Patients who are pregnant, have preexisting diaphragmatic disease or injury, have a tracheostomy, or are not undergoing a first spontaneous breathing trial are excluded and would not benefit from this validation.

Why it matters

Potential benefit: If successful, the VVI could help clinicians identify patients who can be safely taken off mechanical ventilation sooner, reducing ventilation days, complications, and length of stay.

How similar studies have performed: A preliminary internal study reported high accuracy for the VVI, and other diaphragm-ultrasound indices have shown promise, but external validation remains limited.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Mechanically ventilated patients for more than 48h
* First Spontaneous breathing trial
* Deemed as ready to undergo weaning by the treating physician, according to published readiness criteria (DOI: 10.1183/09031936.00010206)

Exclusion Criteria:

* pregnant patients
* preexisting diaphragmatic disease or injury
* tracheostomy

Where this trial is running

Larissa and 2 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Weaning Mechanical Ventilationweaningmechanical ventilationultrasound
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.