Measuring airway opening during out-of-hospital cardiac arrest

Measurement of Airway Opening Index During Out-of-hospital Cardiac Arrest: The Lazarus AOI Trial.

Observational University Hospital, Ghent · NCT07438938

This project tests whether the Airway Opening Index (AOI) measured from capnograms during CPR in adults with out-of-hospital cardiac arrest is common and linked to return of spontaneous circulation.

Quick facts

Study typeObservational
Enrollment150 (estimated)
Ages18 Years and up
SexAll
SponsorUniversity Hospital, Ghent Academic / other
Locations1 site (Ghent, East-Flanders)
Trial IDNCT07438938 on ClinicalTrials.gov

What this trial studies

This retrospective observational cohort uses capnography recordings from about 150 adult out-of-hospital cardiac arrest cases logged in the Lazarus database at Ghent University Hospital. The Airway Opening Index (AOI) will be calculated from capnograms obtained immediately after intubation to quantify airway closure during CPR. The analysis will report AOI prevalence, examine correlations between AOI and return of spontaneous circulation (ROSC), and explore how applied positive airway pressures relate to AOI and outcomes. Results are intended to clarify whether AOI can serve as a CPR quality metric or prognostic indicator.

Who should consider this trial

Good fit: Adults who had an out-of-hospital cardiac arrest, were intubated during CPR, and have available immediate post-intubation capnogram recordings are the intended cases for analysis.

Not a fit: Patients who were not intubated, who did not receive CPR after intubation, or whose capnogram recordings are technically unusable are not eligible and would not benefit from this analysis.

Why it matters

Potential benefit: If successful, this work could provide a simple capnogram-derived marker to help predict ROSC and guide ventilation strategy during CPR.

How similar studies have performed: Capnography patterns and airway closure have been described in prior work, but using a standardized Airway Opening Index (AOI) as a prognostic or quality metric remains relatively novel and not yet widely validated.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Adult (over 18 years old) patients with out-of-hospital cardiac arrest.
* Patients undergoing cardiopulmonary resuscitation (CPR).
* Patients who were intubated and had available capnogram recordings immediately after intubation.

Exclusion Criteria:

* Patients that were not intubated
* Patients that did not receive CPR following intubation
* Cases with a technical challenge with the ETCO₂ measurement (i.e., issues with waveform data of the capnogram.

Where this trial is running

Ghent, East-Flanders

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 Cardiac ArrestOut-of-hospital Cardiac ArrestResuscitated Sudden Cardiac Deathcapnographyairway closure
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.