Comparison of Preoxygenation Techniques in Healthy Volunteers With Monitoring of End-tidal Oxygen Fraction (FeO₂) and Oxygen Reserve Index (ORI) (OXYGAME1)

Comparison of Preoxygenation Techniques in Healthy Volunteers With Monitoring of End-tidal Oxygen Fraction (FeO₂) and Oxygen Reserve Index (ORI).

The objective of this physiological study is to compare two preoxygenation techniques (non-invasive ventilation combined with high-flow nasal oxygen versus non-invasive ventilation alone) by monitoring end-tidal oxygen fraction (FeO₂) and the Oxygen Reserve Index (ORI) during 3 minutes of preoxygenation in healthy volunteers.

Study Overview

• Status: Completed
• Conditions: Healthy
• Intervention / Treatment: Other: Preoxygenation with VNI + OHD; Other: Preoxygenation with VNI

Detailed Description

An intubation procedure is performed in several successive phases:

1. Preoxygenation phase: This phase consists of administering 100% oxygen for 3 to 5 minutes in order to increase oxygen reserves.
2. Alveolar hypoventilation phase: This phase begins with the administration of anesthetic agents, leading to a reduction in spontaneous ventilation.
3. Apnea phase: During this phase, laryngoscopy is performed and the endotracheal tube is inserted into the trachea.
4. Initiation of invasive mechanical ventilation: Once intubation is successful, the patient is placed on assisted mechanical ventilation.

Several devices can be used to perform preoxygenation:

• Bag-valve mask (BVM)
• High-flow nasal cannula therapy (HFNC)
• Non-invasive ventilation (NIV):

Current recommendations from critical care societies suggest the use of:

• BVM or HFNC for non-hypoxemic patients
• NIV for hypoxemic patients A single-center randomized controlled study (OPTINIV) demonstrated the benefit of combining NIV and HFNC for preoxygenation. However, placing an NIV mask over HFNC nasal cannulae may result in mask leaks, leading to ambient air entrainment, as well as a potential risk of excessive airway pressure related to HFNC. In this study, HFNC cannulae in the control group were left in place but inactive. Consequently, it remains difficult to determine whether the observed efficacy of the NIV + HFNC combination was related to leak compensation by HFNC during preoxygenation, or to apneic oxygenation provided by HFNC between laryngoscopy and successful intubation.

• Study Type: Interventional
• Enrollment (Actual): 30
• Phase: Not Applicable

Contacts and Locations

Study Locations

• France
  • Orléans, France, 45067
    • CHU Orléans

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Male or female
• Healthy volunteer who has provided written informed consent
• Age > 18 years

Exclusion Criteria:

• Long-term oxygen therapy
• Cardiac or pulmonary disease (including asthma)
• Presence of Raynaud's syndrome
• Claustrophobia
• Body mass index (BMI) ≥ 30 kg/m²
• Presence of nail polish preventing accurate SpO₂ and ORI measurement
• Under legal protection
• Incarcerated individuals
• Persons deprived of liberty
• Not affiliated to French social security
• Pregnant or breastfeeding women
• Individuals currently participating in a drug study and still within the exclusion period

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Non-invasive ventilation combined to high flow nasal cannula; - NIV + HFNC: Non-invasive ventilation in pressure-controlled mode with inspiratory pressure adjusted to achieve a tidal volume of 6-8 mL/kg (in practice, inspiratory pressure between 5 and 10 cmH₂O) and a PEEP of 5 cmH₂O, combined with high-flow nasal cannula oxygen at 60 L/min with an FiO₂ of 100%	Other: Preoxygenation with VNI + OHD; Each preoxygenation session will last 3 minutes with the participant positioned at a 30° head-up angle. A washout period of 10 minutes will be applied between each preoxygenation session, and initiation of the second preoxygenation technique will require the Oxygen Reserve Index (ORI) to return to 0. Monitoring will include: Oxygen Reserve Index (ORI); End-tidal oxygen fraction (FeO₂) measured at the NIV mask; Peripheral oxygen saturation (SpO₂)
Experimental: Non invasive ventilation; - NIV alone in pressure-controlled mode with inspiratory pressure adjusted to achieve a tidal volume of 6-8 mL/kg (in practice, inspiratory pressure between 5 and 10 cmH₂O) and a PEEP of 5 cmH₂O	Other: Preoxygenation with VNI; Each preoxygenation session will last 3 minutes with the participant positioned at a 30° head-up angle. A washout period of 10 minutes will be applied between each preoxygenation session, and initiation of the second preoxygenation technique will require the Oxygen Reserve Index (ORI) to return to 0. Monitoring will include: Oxygen Reserve Index (ORI); End-tidal oxygen fraction (FeO₂) measured at the NIV mask; Peripheral oxygen saturation (SpO₂)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in end-tidal oxygen fraction (FeO2) at the end of each preoxygenation technique	FeO2 will be collected every 12 seconds during preoxygenation. The mean FeO2 value at 3 minutes will be used for comparison between techniques.	3 minutes

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in end-tidal oxygen fraction (FeO2) during each preoxygenation technique	Change in end-tidal oxygen fraction (FeO₂) will be evaluated by recording FeO₂ every 12 seconds during the 3-minute preoxygenation period.	3 minutes
Maximum FeO2 value	Maximum FeO2 value achieved during the 3 minutes of each preoxygenation technique	3 minutes
Average Oxygen Reserve Index (ORI) value	The ORI will be recorded every 30 seconds during preoxygenation. The mean ORI value at 3 minutes will be used for comparison.	3 minutes
Maximum ORI value	Maximum ORI value achieved during the 3 minutes of each preoxygenation technique	3 minutes
Change in ORI during each preoxygenation technique	Change in ORI will be evaluated by recording ORI every 2 seconds during the 3 minutes of preoxygenation.	3 minutes
Time (in seconds) required to reach an ORI value ≥ 0.60 and FeO2 ≥ 90% during the 3 minutes of each preoxygenation technique		3 minutes
Time (in seconds) for ORI to return to 0 after cessation of preoxygenation.		3 minutes
Change in peripheral oxygen saturation (SpO2) during each preoxygenation technique	The change in SpO2 will be evaluated by recording SpO2 every 12 seconds during the 3 minutes of preoxygenation.	3 minutes
Change in ventilator parameters (inspiratory and expiratory tidal volumes)	Change in inspiratory and expiratory tidal volumes measured every 30 seconds during the 3 minutes of preoxygenation.	3 minutes

Collaborators and Investigators

• Sponsor: Centre Hospitalier Régional d'Orléans
• Investigators: Principal Investigator: Mai-Anh NAH, MD, CHU d'Orléans

Study record dates

Study Major Dates

• Study Start (Actual): March 9, 2026
• Primary Completion (Actual): April 29, 2026
• Study Completion (Actual): April 29, 2026

Study Registration Dates

• First Submitted: December 30, 2025
• First Submitted That Met QC Criteria: December 30, 2025
• First Posted (Actual): January 12, 2026

Study Record Updates

• Last Update Posted (Actual): May 14, 2026
• Last Update Submitted That Met QC Criteria: May 12, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: Healthy volunteers; Non-invasive ventilation; High flow nasal cannula; Noninvasive Ventilation; Preoxygenation
• Other Study ID Numbers: CHUO-2025-21

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No